WorldWideScience

Sample records for survey response bias

  1. Initial nonresponse and survey response mode biases in survey research.

    Science.gov (United States)

    Chi, Donald L; Chen, Chao Ying

    2015-01-01

    We evaluated survey response factors (particularly initial nonresponse and survey mode) that may be associated with bias in survey research. We examined prevention-related beliefs and outcomes for initial mail survey responders (n=209), follow-up mail survey responders (n=78), and follow-up telephone survey responders (n=74). The Pearson chi-square test and analysis of variance identified beliefs and behavioral outcomes associated with survey response mode. Follow-up options to the initial mail survey improved response rates (22.0-38.0 percent). Initial mail survey responders more strongly believed topical fluoride protects teeth from cavities than others (P=0.04). A significantly larger proportion of parents completing a follow-up telephone survey (30.8 percent) refused topical fluoride for their child than those completing mail surveys (10.3-10.4 percent) (Psurveys with follow-up improve response rates. Initial nonresponse and survey response mode may be associated with biases in survey research. © 2015 American Association of Public Health Dentistry.

  2. Response bias in job satisfaction surveys: English general practitioners

    OpenAIRE

    Gravelle, H.; AR Hole, I Hussein

    2008-01-01

    Job satisfaction may affect the propensity to respond to job satisfaction surveys, so that estimates of average satisfaction and the effects of determinants of satisfaction may be biased. We examine response bias using data from a postal job satisfaction survey of family doctors. We link all the sampled doctors to an administrative database and so have information on the characteristics of responders and non-responders. Allowing for selection increases the estimate of mean job satisfaction in...

  3. Cultural differences in survey responding: Issues and insights in the study of response biases.

    Science.gov (United States)

    Kemmelmeier, Markus

    2016-12-01

    This paper introduces the special section "Cultural differences in questionnaire responding" and discusses central topics in the research on response biases in cross-cultural survey research. Based on current conceptions of acquiescent, extreme, and socially desirable responding, the author considers current data on the correlated nature of response biases and the conditions under which different response styles they emerge. Based on evidence relating different response styles to the cultural dimension of individualism-collectivism, the paper explores how research presented as part of this special section might help resolves some tensions in this literature. The paper concludes by arguing that response styles should not be treated merely as measurement error, but as cultural behaviors in themselves.

  4. A randomised trial and economic evaluation of the effect of response mode on response rate, response bias, and item non-response in a survey of doctors.

    Science.gov (United States)

    Scott, Anthony; Jeon, Sung-Hee; Joyce, Catherine M; Humphreys, John S; Kalb, Guyonne; Witt, Julia; Leahy, Anne

    2011-09-05

    Surveys of doctors are an important data collection method in health services research. Ways to improve response rates, minimise survey response bias and item non-response, within a given budget, have not previously been addressed in the same study. The aim of this paper is to compare the effects and costs of three different modes of survey administration in a national survey of doctors. A stratified random sample of 4.9% (2,702/54,160) of doctors undertaking clinical practice was drawn from a national directory of all doctors in Australia. Stratification was by four doctor types: general practitioners, specialists, specialists-in-training, and hospital non-specialists, and by six rural/remote categories. A three-arm parallel trial design with equal randomisation across arms was used. Doctors were randomly allocated to: online questionnaire (902); simultaneous mixed mode (a paper questionnaire and login details sent together) (900); or, sequential mixed mode (online followed by a paper questionnaire with the reminder) (900). Analysis was by intention to treat, as within each primary mode, doctors could choose either paper or online. Primary outcome measures were response rate, survey response bias, item non-response, and cost. The online mode had a response rate 12.95%, followed by the simultaneous mixed mode with 19.7%, and the sequential mixed mode with 20.7%. After adjusting for observed differences between the groups, the online mode had a 7 percentage point lower response rate compared to the simultaneous mixed mode, and a 7.7 percentage point lower response rate compared to sequential mixed mode. The difference in response rate between the sequential and simultaneous modes was not statistically significant. Both mixed modes showed evidence of response bias, whilst the characteristics of online respondents were similar to the population. However, the online mode had a higher rate of item non-response compared to both mixed modes. The total cost of the online

  5. Correcting for non-response bias in contingent valuation surveys concerning environmental non-market goods

    DEFF Research Database (Denmark)

    Bonnichsen, Ole; Olsen, Søren Bøye

    2016-01-01

    to be part of an Internet panel and subsequently whether they wish to participate in the survey, thereby introducing two elements of potential self-selection. These elements may be correlated with preferences, thus making the respondents a non-random and non-representative sample, ultimately biasing results....... This paper analyses a sample used for an Internet contingent valuation method survey eliciting preferences for improvements in water quality of a river. We find that some variables that affect the survey participation decision also affect willingness-to-pay, consequently biasing our welfare estimates. We...... show how adjusting willingness-to-pay for this bias can be accomplished by using a grouped data model incorporating a correlation parameter to account for selection....

  6. Too Many Blood Donors – Response Bias in the Swiss Health Survey 2012

    Science.gov (United States)

    Volken, Thomas; Bänziger, Andreas; Buser, Andreas; Castelli, Damiano; Fontana, Stefano; Frey, Beat M.; Sarraj, Amira; Sigle, Jörg; Thierbach, Jutta; Weingand, Tina; Mansouri-Taleghani, Behrouz

    2016-01-01

    Background Data on blood donor status obtained from general surveys and health interview surveys have been widely used. However, the integrity of data on self-reported blood donor status from surveys may be threatened by sampling and non-sampling error. Our study aimed to compare self-reported blood donors (including one-time as well as regular donors) from the Swiss Health Survey 2012 (SHS) with register-based blood donors recorded by blood establishments and evaluate the direction and magnitude of bias in the SHS. Methods We compared population-weighted SHS point estimates of the number of blood donors with their corresponding 95% confidence intervals to the respective figures from blood donor registries (birth cohorts 1978-1993) and estimates of donors based on period donor tables derived from blood donor registries (birth cohorts 1920-1993). Results In the birth cohorts 1978-1993, the SHS-predicted number of donors was 1.8 times higher than the respective number of donors based on registry data. Adjusting for foreign and naturalized Swiss nationals that immigrated after their 18th birthday, the SHS overall predicted number of donors was 1.6 times higher. Similarly, SHS estimates for the 1920-1993 birth cohorts were 2.4 and 2.1 times higher as compared to register-based estimates. Generally, the differences between SHS and register-based donors were more pronounced in men than in women. Conclusion Self-reported blood donor status in the SHS is biased. Estimates of blood donors are substantially higher than respective estimates based on blood donor registries. PMID:27994526

  7. Methodology of Correcting Nonresponse Bias: Introducing Another Bias? The Case of the Swiss Innovation Survey 2002

    OpenAIRE

    Sydow, Nora

    2006-01-01

    The non-response in a survey can lead to severe bias. In order to manage this problem, it is usual to make a second survey by a sample of non-respondent. This allows us to test if there is a significant difference in the key variables of the survey between respondents and nonrespondents and, if yes, to take it into account. But, the risk is great to introduce another bias depending on the mode (mail vs phone) of survey. The KOF industrial economics group is exploring for many years the innova...

  8. Response bias in plaintiffs' histories.

    Science.gov (United States)

    Lees-Haley, P R; Williams, C W; Zasler, N D; Marguilies, S; English, L T; Stevens, K B

    1997-11-01

    This study investigated response bias in self-reported history of factors relevant to the assessment of traumatic brain injury, toxic brain injury and related emotional distress. Response bias refers to systematic error in self-report data. A total of 446 subjects (comprising 131 litigating and 315 non-litigating adults from five locations in the United States) completed a symptom questionnaire. Data were obtained from university faculty and students, from patients in clinics specializing in physiatry neurology, and family medicine, and from plaintiffs undergoing forensic neuropsychological evaluations. Comparisons were made for litigant and non litigant ratings of their past and current cognitive and emotional functioning, including life in general, ability to concentrate, memory, depression, anxiety, alcohol, drugs, ability to work or attend school, irritability, headaches, confusion, self-esteem, and fatigue. Although there is no basis for hypothesizing plaintiffs to be healthier than the general population, plaintiffs rated their pre-injury functioning superior to non-plaintiffs. These findings suggest that response biases need to be taken into account by forensic examiners when relying on litigants' self-reports of pre-injury status.

  9. Assessment of Non-Response Bias in Estimates of Alcohol Consumption: Applying the Continuum of Resistance Model in a General Population Survey in England

    Science.gov (United States)

    Scholes, Shaun; Shelton, Nicola; Connor, Jennie

    2017-01-01

    Background Previous studies have shown heavier drinkers are less likely to respond to surveys and require extended efforts to recruit. This study applies the continuum of resistance model to explore how survey estimates of alcohol consumption may be affected by non-response bias in three consecutive years of a general population survey in England. Methods Using the Health Survey for England (HSE) survey years 2011–13, number of contact attempts (1–6 and 7+) were explored by socio-demographic and drinking characteristics. The odds of drinking more than various thresholds were modelled using logistic regression. Assuming that non-participants were similar to those who were difficult to contact (the continuum of resistance model), the effect of non-response on measures of drinking was investigated. Results In the fully-adjusted regression model, women who required 7+ calls were significantly more likely to drink more than the UK Government’s recommended daily limit (OR 1.19, 95% CI 1.06–1.33, P = 0.003) and to engage in heavy episodic drinking (OR 1.23, 95% CI 1.07–1.42, P = 0.004), however this was not significant in men in the fully-adjusted model. When the continuum of resistance model was applied, there was an increase in average weekly alcohol consumption of 1.8 units among men (a 12.6% relative increase), and an increase of 1.5 units among women (a 20.5% relative increase). There was also an increase in the prevalence of heavy episodic drinking of 2.5% among men (an 12.0% relative increase) and of 2.0% among women (a 15.8% relative increase), although other measures of drinking were less affected. Conclusion Overall alcohol consumption and the prevalence of heavy episodic drinking were higher among HSE participants who required more extended efforts to contact. The continuum of resistance model suggests non-response bias does affect survey estimates of alcohol consumption. PMID:28141834

  10. Measuring Nonresponse Bias in a Cross-Country Enterprise Survey

    Directory of Open Access Journals (Sweden)

    Katarzyna Bańkowska

    2015-04-01

    Full Text Available Nonresponse is a common issue affecting the vast majority of surveys. Efforts to convince those unwilling to participate in a survey might not necessary result in a better picture of the target population and can lead to higher, not lower, nonresponse bias.We investigate the impact of non-response in the European Commission & European Central Bank Survey on the Access to Finance of Enterprises (SAFE, which collects evidence on the financing conditions faced by European SMEs compared with those of large firms. This survey, conducted by telephone bi-annually since 2009 by the ECB and the European Commission, provides a valuable means to search for this kind of bias, given the high heterogeneity of response propensities across countries.The study relies on so-called “Representativity Indicators” developed within the Representativity Indicators of Survey Quality (RISQ project, which measure the distance to a fully representative response. On this basis, we examine the quality of the SAFE Survey at different stages of the fieldwork as well as across different survey waves and countries. The RISQ methodology relies on rich sampling frame information, which is however partly limited in the case of the SAFE. We also assess the representativeness of the SAFE particular subsample created by linking the survey responses with the companies’ financial information from a business register; this sub-sampling is another potential source of bias which we also attempt to quantify. Finally, we suggest possible ways how to improve monitoring of the possible nonresponse bias in the future rounds of the survey.

  11. Maximum Likelihood Under Response Biased Sampling\\ud

    OpenAIRE

    Chambers, Raymond; Dorfman, Alan; Wang, Suojin

    2003-01-01

    Informative sampling occurs when the probability of inclusion in sample depends on\\ud the value of the survey response variable. Response or size biased sampling is a\\ud particular case of informative sampling where the inclusion probability is proportional\\ud to the value of this variable. In this paper we describe a general model for response\\ud biased sampling, which we call array sampling, and develop maximum likelihood and\\ud estimating equation theory appropriate to this situation. The ...

  12. Interloper bias in future large-scale structure surveys

    CERN Document Server

    Pullen, Anthony R; Dore, Olivier; Raccanelli, Alvise

    2015-01-01

    Next-generation spectroscopic surveys will map the large-scale structure of the observable universe, using emission line galaxies as tracers. While each survey will map the sky with a specific emission line, interloping emission lines can masquerade as the survey's intended emission line at different redshifts. Interloping lines from galaxies that are not removed can contaminate the power spectrum measurement, mixing correlations from various redshifts and diluting the true signal. We assess the potential for power spectrum contamination, finding that an interloper fraction worse than 0.2% could bias power spectrum measurements for future surveys by more than 10% of statistical errors, while also biasing inferences based on the power spectrum. We also construct a formalism for predicting biases for cosmological parameter measurements, and we demonstrate that a 0.3% interloper fraction could bias measurements of the growth rate by more than 10% of the error, which can affect constraints from upcoming surveys o...

  13. [The National Danish Survey of Patient Experiences has a small positive bias].

    Science.gov (United States)

    Rosenstjerne Andersen, Angelo; Fuglsang, Marie; Kyed, Daisy

    2012-10-01

    The response rate in The National Danish Survey of Patient Experiences in 2009 was 54%. In order to evaluate bias due to non-responders, The Unit of Patient-perceived Quality merged survey data and data on patient background from Statistics Denmark. The relationships between the responding patients' background and their answers to six questions in the survey questionnaire are estimated with logistic regression analysis and subsequently used for predicting the answers of the non-responders. Results indicate a small positive bias in four of the questions and no bias in the remaining two.

  14. Starting-point bias and respondent uncertainty in dichotomous choice contingent valuation surveys

    OpenAIRE

    Flachaire, Emmanuel; Hollard, Guillaume

    2007-01-01

    International audience; In this article, we develop a dichotomous choice model with follow-up questions that describes the willingness to pay being uncertain in an interval. The initial response is subject to starting point bias. Our model provides an alternative interpretation of the starting point bias in the dichotomous choice valuation surveys. Using the Exxon Valdez survey, we show that, when uncertain, individuals tend to answer "yes".

  15. Shear calibration biases in weak lensing surveys

    CERN Document Server

    Hirata, C M; Hirata, Christopher M.; Seljak, Uros

    2003-01-01

    We investigate biases induced by the conversion between the observed image shape to shear distortion in current weak lensing analysis methods. Such overall calibration biases cannot be detected by the standard tests such as E/B decomposition or calibration with stars. We find that the non-Gaussianity of point spread function has a significant effect and can lead to up to 15 per cent error on the linear amplitude of fluctuations sigma_8 depending on the method of analysis. This could explain some of the discrepancies seen in recent amplitude determinations from weak lensing. Using an elliptical Laguerre expansion method we develop a re-Gaussianization method which reduces the error to calibration error of order 1 per cent even for poorly resolved galaxies. We also discuss a new type of shear selection bias which results in up to roughly 8 percent underestimation of the signal. It is expected to scale with redshift, inducing errors in the growth factor extraction if not properly corrected for. Understanding and...

  16. A procedure for eliminating additive bias from cross-cultural survey data

    DEFF Research Database (Denmark)

    Scholderer, Joachim; Grunert, Klaus G.; Brunsø, Karen

    2005-01-01

    additive bias from cross-cultural data. The procedure involves four steps: (1) embed a potentially biased item in a factor-analytic measurement model, (2) test for the existence of additive bias between populations, (3) use the factor-analytic model to estimate the magnitude of the bias, and (4) replace...... differences in the understanding of item wording or response category labels. However, experience suggests that additive bias can be found more often than not. Based on the concept of partial measurement invariance (Byrne, Shavelson and Muthén 1989), the present paper develops a procedure for eliminating......Measurement bias in cross-cultural surveys can seriously threaten the validity of hypothesis tests. Direct comparisons of means depend on the assumption that differences in observed variables reflect differences in the underlying constructs, and not an additive bias that may be caused by cultural...

  17. [Potential selection bias in telephone surveys: landline and mobile phones].

    Science.gov (United States)

    Garcia-Continente, Xavier; Pérez-Giménez, Anna; López, María José; Nebot, Manel

    2014-01-01

    The increasing use of mobile phones in the last decade has decreased landline telephone coverage in Spanish households. This study aimed to analyze sociodemographic characteristics and health indicators by type of telephone service (mobile phone vs. landline or landline and mobile phone). Two telephone surveys were conducted in Spanish samples (February 2010 and February 2011). Multivariate logistic regression analyses were performed to analyze differences in the main sociodemographic characteristics and health indicators according to the type of telephone service available in Spanish households. We obtained 2027 valid responses (1627 landline telephones and 400 mobile phones). Persons contacted through a mobile phone were more likely to be a foreigner, to belong to the manual social class, to have a lower educational level, and to be a smoker than those contacted through a landline telephone. The profile of the population that has only a mobile phone differs from that with a landline telephone. Therefore, telephone surveys that exclude mobile phones could show a selection bias. Copyright © 2013 SESPAS. Published by Elsevier Espana. All rights reserved.

  18. Geographic Information System mapping as a tool to assess nonresponse bias in survey research.

    Science.gov (United States)

    Hansen, Richard A; Henley, Amanda Clarke; Brouwer, Emily S; Oraefo, Adaora N; Roth, Mary T

    2007-09-01

    Surveys are a useful tool for assessing professional practice patterns, although declining response rates have caused concern over external validity. This is particularly relevant to Web-based surveys, where response rates traditionally have been lower than with paper mail surveys. In a 2005 survey of North Carolina community pharmacy managers using a Web-based data collection instrument, we achieved an overall response rate of 23%. To explore nonresponse bias using accepted methods and to test whether Geographic Information System mapping is a useful tool for assessing response bias. Cross-sectional survey of 1593 community pharmacy managers in North Carolina using a Web-based tool. Nonresponse bias was assessed quantitatively by comparing early responders with late responders (ie, wave analysis) and by comparing respondents with nonrespondents with regard to known pharmacy, pharmacist, and population characteristics. Significant variables from these analyses were then mapped using ArcGIS 9.1. Pharmacy type was identified as a predictor of response, with independent pharmacies less likely to respond than chain pharmacies (odds ratio 0.75; 95% confidence interval 0.59-0.95). This conclusion was consistent in the wave analysis and the analysis of known population characteristics. Other county-level variables such as the number of physicians per capita, income, and the percentage of residents eligible for Medicaid showed trends but were not statistically significant (Ppharmacy type but trends were more difficult to detect for statistically insignificant trends. The best way to avoid nonresponse bias is to improve response rates. When this is not possible, Geographic Information System mapping has some utility for assessing nonresponse bias, and for aggregating known population characteristics based on location. It is most useful in conjunction with other accepted techniques such as wave analysis and analysis of known population characteristics.

  19. Cross-situational consistency in recognition memory response bias.

    Science.gov (United States)

    Kantner, Justin; Lindsay, D Stephen

    2014-10-01

    Individuals taking an old-new recognition memory test differ widely in their bias to respond "old," ranging from strongly conservative to strongly liberal, even without any manipulation intended to affect bias. Kantner and Lindsay (2012) found stability of bias across study-test cycles, suggesting that bias is a cognitive trait. That consistency, however, could have arisen because participants perceived the two tests as being part of the same experiment in the same context. In the present study, we tested for stability across two recognition study-test procedures embedded in markedly different experiments, held weeks apart, that participants did not know were connected. Bias showed substantial cross-situational stability. Moreover, bias weakly predicted identifications on an eyewitness memory task and accuracy on a go-no-go task. Although we found little in the way of relationships between bias and five personality measures, these findings suggest that response bias is a stable and broadly influential characteristic of recognizers.

  20. Using cognitive bias modification to deflate responsibility in compulsive checkers

    NARCIS (Netherlands)

    Grisham, Jessica R; Becker, Lauren; Williams, A.D.; Whitton, Alexis; Makkar, Steve

    2014-01-01

    Cognitive-behavioural models of compulsive checking posit a dominant role for beliefs regarding one’s responsibility to prevent harm. In the current study we employed a computerised cognitive bias modification of interpretation (CBM-I) paradigm to target and modify responsibility biases in a sample

  1. Using cognitive bias modification to deflate responsibility in compulsive checkers

    NARCIS (Netherlands)

    Grisham, Jessica R; Becker, Lauren; Williams, A.D.; Whitton, Alexis; Makkar, Steve

    2014-01-01

    Cognitive-behavioural models of compulsive checking posit a dominant role for beliefs regarding one’s responsibility to prevent harm. In the current study we employed a computerised cognitive bias modification of interpretation (CBM-I) paradigm to target and modify responsibility biases in a sample

  2. The problem of bias when nursing facility staff administer customer satisfaction surveys.

    Science.gov (United States)

    Hodlewsky, R Tamara; Decker, Frederic H

    2002-10-01

    Customer satisfaction instruments are being used with increasing frequency to assess and monitor residents' assessments of quality of care in nursing facilities. There is no standard protocol, however, for how or by whom the instruments should be administered when anonymous, written responses are not feasible. Researchers often use outside interviewers to assess satisfaction, but cost considerations may limit the extent to which facilities are able to hire outside interviewers on a regular basis. This study was designed to investigate the existence and extent of any bias caused by staff administering customer satisfaction surveys. Customer satisfaction data were collected in 1998 from 265 residents in 21 nursing facilities in North Dakota. Half the residents in each facility were interviewed by staff members and the other half by outside consultants; scores were compared by interviewer type. In addition to a tabulation of raw scores, ordinary least-squares analysis with facility fixed effects was used to control for resident characteristics and unmeasured facility-level factors that could influence scores. Significant positive bias was found when staff members interviewed residents. The bias was not limited to questions directly affecting staff responsibilities but applied across all types of issues. The bias was robust under varying constructions of satisfaction and dissatisfaction. A uniform method of survey administration appears to be important if satisfaction data are to be used to compare facilities. Bias is an important factor that should be considered and weighed against the costs of obtaining outside interviewers when assessing customer satisfaction among long term care residents.

  3. Non-response bias in physical activity trend estimates

    Directory of Open Access Journals (Sweden)

    Bauman Adrian

    2009-11-01

    Full Text Available Abstract Background Increases in reported leisure time physical activity (PA and obesity have been observed in several countries. One hypothesis for these apparently contradictory trends is differential bias in estimates over time. The purpose of this short report is to examine the potential impact of changes in response rates over time on the prevalence of adequate PA in Canadian adults. Methods Participants were recruited in representative national telephone surveys of PA from 1995-2007. Differences in PA prevalence estimates between participants and those hard to reach were assessed using Student's t tests adjusted for multiple comparisons. Results The number of telephone calls required to reach and speak with someone in the household increased over time, as did the percentage of selected participants who initially refused during the first interview attempt. A higher prevalence of adequate PA was observed with 5-9 attempts to reach anyone in the household in 1999-2002, but this was not significant after adjustment for multiple comparisons. Conclusion No significant impact on PA trend estimates was observed due to differential non response rates. It is important for health policy makers to understand potential biases and how these may affect secular trends in all aspects of the energy balance equation.

  4. Formal definitions of measurement bias and explanation bias clarify measurement and conceptual perspectives on response shift

    NARCIS (Netherlands)

    Oort, F.J.; Visser, M.R.M.; Sprangers, M.A.G.

    2009-01-01

    Objective: Response shift is generally associated with a change in the meaning of test scores, impeding the comparison of repeated measurements. Still, different researchers have different views of response shift. From a measurement perspective, response shift can be considered as bias in the measur

  5. [Several common biases and control measures during sampling survey of eye diseases in China].

    Science.gov (United States)

    Guan, Huai-jin

    2008-06-01

    Bias is a common artificial error during sampling survey in eye diseases, and is a major impact factor for validity and reliability of the survey. The causes and the control measures of several biases regarding current sampling survey of eye diseases in China were analyzed and discussed, including the sampling bias, non-respondent bias, and diagnostic bias. This review emphasizes that controlling bias is the key to ensure quality of sampling survey. Random sampling, sufficient sample quantity, careful examination and taking history, improving examination rate, accurate diagnosis, strict training and preliminary study, as well as quality control can eliminate or minimize biases and improve the sampling survey quality of eye diseases in China

  6. Evidence for biasing in the CfA survey

    Science.gov (United States)

    Hamilton, A. J. S.

    1988-01-01

    Intrinsically bright galaxies appear systematically more correlated than faint galaxies in the Center for Astrophysics redshift survey. The amplification of the two-point correlation function behaves exponentially with luminosity, being essentially flat up to the knee of the luminosity function, then increasing markedly. The amplification reaches a factor of 3.5e + or - 0.4 in the very brightest galaxies. The effect is dominated by spirals rather than ellipticals, so that the correlation function of bright spirals becomes comparable to that of normal ellipticals. Similar results are obtained whether the correlation function is measured in two or three dimensions. The effect persists to separations of a correlation length or more, and is not confined to the cores of the Virgo, Coma, and Abell 1367 clusters, suggesting that the effect is caused by biasing, that is, galaxies kindle preferentially in more clustered regions, rather than by gravitational relaxation.

  7. Transcending Bias through Reader-Response Theory

    Science.gov (United States)

    Soublis, Theoni; Winkler, Erik

    2004-01-01

    The preservice teachers from all disciplines will be benefited if they incorporate reading in their classes according to Dr. Louise Rosenblatt's reader-response theory. A teacher's experience with her students while reading Chris Crutcher's "Staying Fat for Sarah Byanes" in the Secondary Content Area and a student's response on the novel are…

  8. Surveys from inside: An assessment of unit nonresponse bias with internal criteria

    Directory of Open Access Journals (Sweden)

    Ulrich Kohler

    2007-06-01

    Full Text Available The article uses the so called “internal criteria of representativeness” to assess the unit nonresponse bias in five European comparative survey projects. It then goes on investigating several ideas why unit nonresponse bias might vary between surveys and countries. It is proposed that unit nonresponse bias is either caused by country characteristics or survey methodology. The empirical evidence presented speaks more in favour of the latter than of the former. Among the survey characteristics the features that strengthen the leverage to control interviewers’ behaviour have top priority

  9. Mood-congruent free recall bias in anxious individuals is not a consequence of response bias.

    Science.gov (United States)

    Russo, Riccardo; Whittuck, Dora; Roberson, Debi; Dutton, Kevin; Georgiou, George; Fox, Elaine

    2006-05-01

    The status of mood-congruent free recall bias in anxious individuals was evaluated following incidental encoding of target words. Individuals with high and low levels of trait anxiety completed a modified Stroop task, which revealed an attentional bias for threat-related stimuli in anxious individuals. This group was significantly slower in naming the colour in which threat-related words were displayed compared to neutral words. In a subsequent free recall test for the words used in the modified Stroop task, anxious individuals recalled more threat-related words compared to low-anxious people. This difference was significant even when controlling for the false recall of items that had not been presented during study. These results support the view put forward by Russo, Fox, Bellinger, and Nguyen-Van-Tam (2001) that mood-congruent free recall bias in anxious individuals can be observed if the target material is encoded at a relatively shallow level. Moreover, contrary to Dowens and Calvo (2003), the current results show that the memory advantage for threat-related information in anxious individuals is not a consequence of response bias.

  10. Lessons learnt on biases and uncertainties in personal exposure measurement surveys of radiofrequency electromagnetic fields with exposimeters.

    Science.gov (United States)

    Bolte, John F B

    2016-09-01

    Personal exposure measurements of radio frequency electromagnetic fields are important for epidemiological studies and developing prediction models. Minimizing biases and uncertainties and handling spatial and temporal variability are important aspects of these measurements. This paper reviews the lessons learnt from testing the different types of exposimeters and from personal exposure measurement surveys performed between 2005 and 2015. Applying them will improve the comparability and ranking of exposure levels for different microenvironments, activities or (groups of) people, such that epidemiological studies are better capable of finding potential weak correlations with health effects. Over 20 papers have been published on how to prevent biases and minimize uncertainties due to: mechanical errors; design of hardware and software filters; anisotropy; and influence of the body. A number of biases can be corrected for by determining multiplicative correction factors. In addition a good protocol on how to wear the exposimeter, a sufficiently small sampling interval and sufficiently long measurement duration will minimize biases. Corrections to biases are possible for: non-detects through detection limit, erroneous manufacturer calibration and temporal drift. Corrections not deemed necessary, because no significant biases have been observed, are: linearity in response and resolution. Corrections difficult to perform after measurements are for: modulation/duty cycle sensitivity; out of band response aka cross talk; temperature and humidity sensitivity. Corrections not possible to perform after measurements are for: multiple signals detection in one band; flatness of response within a frequency band; anisotropy to waves of different elevation angle. An analysis of 20 microenvironmental surveys showed that early studies using exposimeters with logarithmic detectors, overestimated exposure to signals with bursts, such as in uplink signals from mobile phones and Wi

  11. Scientific Research or Advocacy? Emotive Labels and Selection Bias Confound Survey Results

    Directory of Open Access Journals (Sweden)

    Jerome K. Vanclay

    2000-07-01

    Full Text Available Robert Costanza presents four compelling visions of the future, but the language he uses to describe them is emotive and value-laden and may bias the survey results. The descriptions and analogies used may evoke responses from the survey participants that reveal more about their reactions to the description than their attitudes toward a given scenario. It is hypothesized that the use of more neutral language may lead to more support for the scenario involving "self-limited consumption with ample resources" that Costanza calls "Big Government." If this hypothesis is correct, then the skeptic's policy that Costanza appears to prefer has the additional advantage of always leading to the favored outcome, regardless of the state of the world.

  12. Do Young and Old Preschoolers Exhibit Response Bias Due to Different Mechanisms? Investigating Children's Response Time

    Science.gov (United States)

    Okanda, Mako; Itakura, Shoji

    2011-01-01

    Previous studies have suggested that younger preschoolers exhibit a yes bias due to underdeveloped cognitive abilities, whereas older preschoolers exhibit a response bias due to other factors. To test this hypothesis, we investigated the response latency to yes-no questions pertaining to familiar and unfamiliar objects in 3- to 6-year-olds. The…

  13. Racial bias in neural empathic responses to pain.

    Science.gov (United States)

    Contreras-Huerta, Luis Sebastian; Baker, Katharine S; Reynolds, Katherine J; Batalha, Luisa; Cunnington, Ross

    2013-01-01

    Recent studies have shown that perceiving the pain of others activates brain regions in the observer associated with both somatosensory and affective-motivational aspects of pain, principally involving regions of the anterior cingulate and anterior insula cortex. The degree of these empathic neural responses is modulated by racial bias, such that stronger neural activation is elicited by observing pain in people of the same racial group compared with people of another racial group. The aim of the present study was to examine whether a more general social group category, other than race, could similarly modulate neural empathic responses and perhaps account for the apparent racial bias reported in previous studies. Using a minimal group paradigm, we assigned participants to one of two mixed-race teams. We use the term race to refer to the Chinese or Caucasian appearance of faces and whether the ethnic group represented was the same or different from the appearance of the participant' own face. Using fMRI, we measured neural empathic responses as participants observed members of their own group or other group, and members of their own race or other race, receiving either painful or non-painful touch. Participants showed clear group biases, with no significant effect of race, on behavioral measures of implicit (affective priming) and explicit group identification. Neural responses to observed pain in the anterior cingulate cortex, insula cortex, and somatosensory areas showed significantly greater activation when observing pain in own-race compared with other-race individuals, with no significant effect of minimal groups. These results suggest that racial bias in neural empathic responses is not influenced by minimal forms of group categorization, despite the clear association participants showed with in-group more than out-group members. We suggest that race may be an automatic and unconscious mechanism that drives the initial neural responses to observed pain in

  14. Racial bias in neural empathic responses to pain.

    Directory of Open Access Journals (Sweden)

    Luis Sebastian Contreras-Huerta

    Full Text Available Recent studies have shown that perceiving the pain of others activates brain regions in the observer associated with both somatosensory and affective-motivational aspects of pain, principally involving regions of the anterior cingulate and anterior insula cortex. The degree of these empathic neural responses is modulated by racial bias, such that stronger neural activation is elicited by observing pain in people of the same racial group compared with people of another racial group. The aim of the present study was to examine whether a more general social group category, other than race, could similarly modulate neural empathic responses and perhaps account for the apparent racial bias reported in previous studies. Using a minimal group paradigm, we assigned participants to one of two mixed-race teams. We use the term race to refer to the Chinese or Caucasian appearance of faces and whether the ethnic group represented was the same or different from the appearance of the participant' own face. Using fMRI, we measured neural empathic responses as participants observed members of their own group or other group, and members of their own race or other race, receiving either painful or non-painful touch. Participants showed clear group biases, with no significant effect of race, on behavioral measures of implicit (affective priming and explicit group identification. Neural responses to observed pain in the anterior cingulate cortex, insula cortex, and somatosensory areas showed significantly greater activation when observing pain in own-race compared with other-race individuals, with no significant effect of minimal groups. These results suggest that racial bias in neural empathic responses is not influenced by minimal forms of group categorization, despite the clear association participants showed with in-group more than out-group members. We suggest that race may be an automatic and unconscious mechanism that drives the initial neural responses to

  15. Survey non-response in the Netherlands : Effects on prevalence estimates and associations

    NARCIS (Netherlands)

    Van Loon, AJM; Tijhuis, M; Picavet, HSJ; Surtees, PG; Ormel, J

    2003-01-01

    PURPOSE: Differences in respondent characteristics may lead to bias in prevalence estimates and bias in associations. Both forms of non-response bias are investigated in a study on psychosocial factors and cancer risk, which is a sub-study of a large-scale monitoring survey in the Netherlands. METHO

  16. Heterogeneous interpretation of “household expenditure” in survey reports : evidence and implications of bias

    OpenAIRE

    Comerford, David; Delaney, Liam

    2010-01-01

    This paper addresses respondents’ interpretation of the term “household expenditure” when answering survey questions. A sizeable minority of respondents do not attempt to include all transactions made by every household member, interpreting the question as eliciting individual consumption. This biases estimates of expenditure downward. Furthermore, this bias is predicted by respondent characteristics.

  17. Can I use a Panel? Panel Conditioning and Attrition Bias in Panel Surveys

    NARCIS (Netherlands)

    Das, J.W.M.; Toepoel, V.; van Soest, A.H.O.

    2007-01-01

    Over the past decades there has been an increasing use of panel surveys at the household or individual level, instead of using independent cross-sections. Panel data have important advantages, but there are also two potential drawbacks: attrition bias and panel conditioning effects. Attrition bias c

  18. A method for additive bias correction in cross-cultural surveys

    DEFF Research Database (Denmark)

    Scholderer, Joachim; Grunert, Klaus G.; Brunsø, Karen

    2001-01-01

    Measurement bias in cross-cultural surveys can seriously threaten the validity of hypothesis tests. Direct comparisons of means depend on the assumption that differences in observed variables reflect differences in the underlying constructs, and not an additive bias that may be caused by cultural...

  19. Neural correlates of social perception on response bias.

    Science.gov (United States)

    Shin, Yeon Soon; Kim, Hye-Young; Han, Sanghoon

    2014-07-01

    Accurate person perception is crucial in social decision-making. One of the central elements in successful social perception is the ability to understand another's response bias; this is because the same behavior can represent different inner states depending on whether other people are yea-sayers or naysayers. In the present study, we have tried to investigate how the internal biases of others are perceived. Using a multi-trial learning paradigm, perceivers made predictions about a target's responses to various suggested activities and then received feedback for each prediction trial-by-trial. Our hypotheses were that (1) the internal decision criterion of the targets would be realized through repeated experiences, and (2) due to positive-negative asymmetry, yea-sayers would be recognized more gradually than naysayers through the probabilistic integration of repeated experiences. To find neural evidence that tracks probabilistic integration when forming person knowledge on response biases, we employed a model-based fMRI with a State-Space Model. We discovered that person knowledge about yea-sayers modulated several brain regions, including caudate nucleus, DLPFC, hippocampus, etc. Moreover, when person knowledge was updated with incorrect performance feedback, brain regions including the caudate nucleus, DLPFC, dmPFC, and TPJ were also involved. There were overlapping regions for both processes, caudate nucleus and DLPFC, suggesting that these regions take crucial roles in forming person knowledge with repeated feedback, while reflecting acquired information up to the current prediction. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. The impact of response bias on estimates of health care utilization in a metropolitan area: The use of administrative data

    NARCIS (Netherlands)

    Reijneveld, S.A.; Stronks, K.

    1999-01-01

    Background. Surveys among the general population are an important method for collecting epidemiological data on health and utilization of health care in that population. Selective non-response may affect the validity of these data. This study examines the impact of response bias on estimates of

  1. Sources of Response Bias in Older Ethnic Minorities: A Case of Korean American Elderly

    Science.gov (United States)

    Kim, Miyong T.; Ko, Jisook; Yoon, Hyunwoo; Kim, Kim B.; Jang, Yuri

    2015-01-01

    The present study was undertaken to investigate potential sources of response bias in empirical research involving older ethnic minorities and to identify prudent strategies to reduce those biases, using Korean American elderly (KAE) as an example. Data were obtained from three independent studies of KAE (N=1,297; age ≥60) in three states (Florida, New York, and Maryland) from 2000 to 2008. Two common measures, Pearlin’s Mastery Scale and the CES-D scale, were selected for a series of psychometric tests based on classical measurement theory. Survey items were analyzed in depth, using psychometric properties generated from both exploratory factor analysis and confirmatory factor analysis as well as correlational analysis. Two types of potential sources of bias were identified as the most significant contributors to increases in error variances for these psychological instruments. Error variances were most prominent when (1) items were not presented in a manner that was culturally or contextually congruent with respect to the target population and/or (2) the response anchors for items were mixed (e.g., positive vs. negative). The systemic patterns and magnitudes of the biases were also cross-validated for the three studies. The results demonstrate sources and impacts of measurement biases in studies of older ethnic minorities. The identified response biases highlight the need for re-evaluation of current measurement practices, which are based on traditional recommendations that response anchors should be mixed or that the original wording of instruments should be rigidly followed. Specifically, systematic guidelines for accommodating cultural and contextual backgrounds into instrument design are warranted. PMID:26049971

  2. Handling Protest Responses in Contingent Valuation Surveys.

    Science.gov (United States)

    Pennington, Mark; Gomes, Manuel; Donaldson, Cam

    2017-08-01

    Protest responses, whereby respondents refuse to state the value they place on the health gain, are commonly encountered in contingent valuation (CV) studies, and they tend to be excluded from analyses. Such an approach will be biased if protesters differ from non-protesters on characteristics that predict their responses. The Heckman selection model has been commonly used to adjust for protesters, but its underlying assumptions may be implausible in this context. We present a multiple imputation (MI) approach to appropriately address protest responses in CV studies, and compare it with the Heckman selection model. This study exploits data from the multinational EuroVaQ study, which surveyed respondents' willingness-to-pay (WTP) for a Quality Adjusted Life Year (QALY). Here, our simulation study assesses the relative performance of MI and Heckman selection models across different realistic settings grounded in the EuroVaQ study, including scenarios with different proportions of missing data and non-response mechanisms. We then illustrate the methods in the EuroVaQ study for estimating mean WTP for a QALY gain. We find that MI provides lower bias and mean squared error compared with the Heckman approach across all considered scenarios. The simulations suggest that the Heckman approach can lead to considerable underestimation or overestimation of mean WTP due to violations in the normality assumption, even after log-transforming the WTP responses. The case study illustrates that protesters are associated with a lower mean WTP for a QALY gain compared with non-protesters, but that the results differ according to method for handling protesters. MI is an appropriate method for addressing protest responses in CV studies.

  3. BIAS IN THE MEASUREMENT OF QUALITY OF LIFE: RESPONSE SHIFT

    Directory of Open Access Journals (Sweden)

    Yesim SENOL

    2006-10-01

    Full Text Available Quality of Life (QoL is a descriptive term that refers to people’s emotional, social and physical wellbeing, and their ability to function in the ordinary task of living. The importance of QoL makes it critical to improve and refine measure to understand patients’ experience of health, illness and treatment. However individuals change with time and the basis on which they make a QoL judgment may also change, a phenomenon increasingly referred to as response shift. The definition of response shift is recalibration of internal standards of measurement and reconceptualization of the meaning of item. The purpose of study is to discuss the effects of response shift bias. [TAF Prev Med Bull 2006; 5(5.000: 382-389

  4. Survey of spectral response measurements for photovoltaic devices

    Energy Technology Data Exchange (ETDEWEB)

    Hartman, J.S.; Lind, M.A.

    1981-11-01

    A survey of the photovoltaic community was conducted to ascertain the present state-of-the-art for PV spectral response measurements. Specific topics explored included measurement system designs, good and bad features of the systems, and problems encountered in the evaluation of specific cell structures and materials. The survey showed that most spectral response data are used in diagnostic analysis for the optimization of developmental solar cells. Measurement systems commonly utilize a chopped narrowband source in conjunction with a constant bias illumination which simulates the ambient end use environment. Researchers emphasized the importance of bias illumination for all types of cells in order to minimize the effects of nonlinearities in cell response. Not surprisingly single crystal silicon cells present the fewest measurement problems to the researcher and have been studied more thoroughly than any other type of solar cell. But, the accurate characterization of silicon cells is still difficult and laboratory intercomparison studies have yielded data scatter ranging from +-5% to +-15%. The measurement experience with other types of cells is less extensive. The development of reliable data bases for some solar cells is complicated by problems of cell nonuniformity, environmental instability, nonlinearity, etc. Cascade cells present new problems associated with their structue (multiple cells in series) which are just beginning to be understood. In addition, the importance of many measurement parameters (spectral content of bias light, bias light intensity, bias voltage, chopping frequency, etc.) are not fully understood for most types of solar cells.

  5. The Effect of Halo Assembly Bias on Self Calibration in Galaxy Cluster Surveys

    CERN Document Server

    Wu, Hao-Yi; Wechsler, Risa H

    2008-01-01

    Self-calibration techniques for analyzing cluster counts rely on using the abundance and the clustering amplitude of clusters to simultaneously constrain cosmological parameters and the relation between halo mass and its observable mass tracer. It was recently discovered that the clustering amplitude of halos depends not only on halo mass, but also on various secondary variables such as halo formation time and concentration; these dependences are collectively termed ``assembly bias.'' Using a modified Fisher matrix formalism, we explore whether these secondary variables have a significant impact on studying the properties of dark energy with self calibration in current (SDSS) and near future (DES, SPT, and LSST) cluster surveys. We find that for an SDSS-like survey, secondary dependences of halo bias are insignificant given the expected large statistical uncertainties in dark energy parameters. For SPT- or DES-like survey volumes, we find that the dependence of halo bias on secondary variables is not a signif...

  6. Placebo effect studies are susceptible to response bias and to other types of biases

    DEFF Research Database (Denmark)

    Hróbjartsson, Asbjørn; Kaptchuk, Ted J; Miller, Franklin G

    2011-01-01

    Investigations of the effect of placebo are often challenging to conduct and interpret. The history of placebo shows that assessment of its clinical significance has a real potential to be biased. We analyze and discuss typical types of bias in studies on placebo.......Investigations of the effect of placebo are often challenging to conduct and interpret. The history of placebo shows that assessment of its clinical significance has a real potential to be biased. We analyze and discuss typical types of bias in studies on placebo....

  7. Placebo effect studies are susceptible to response bias and to other types of biases

    DEFF Research Database (Denmark)

    Hróbjartsson, Asbjørn; Kaptchuk, Ted J; Miller, Franklin G

    2011-01-01

    Investigations of the effect of placebo are often challenging to conduct and interpret. The history of placebo shows that assessment of its clinical significance has a real potential to be biased. We analyze and discuss typical types of bias in studies on placebo....

  8. Combining spectroscopic and photometric surveys using angular cross-correlations III: Galaxy bias and stochastisity

    CERN Document Server

    Eriksen, Martin

    2015-01-01

    In the first paper of this series, we studied the effect of baryon acoustic oscillations (BAO), redshift space distortions (RSD) and weak lensing (WL) on measurements of angular cross-correlations in narrow redshift bins. Paper-II presented a multitracer forecast as Figures of Merit (FoM), combining a photometric and spectroscopic stage-IV survey. The uncertainties from galaxy bias, the way light traces mass, is an important ingredient in the forecast. Fixing the bias would increase our FoM equivalent to 3.3 times larger area for the combined constraints. This paper focus on how the modelling of bias affect these results. In the combined forecast, lensing both help and benefit from the improved bias measurements in overlapping surveys after marginalizing over the cosmological parameters. Adding a second lens population in counts-shear does not have a large impact on bias error, but removing all counts-shear information increases the bias error in a significant way. We also discuss the relative impact of WL, m...

  9. Gender anomalies in stated preference surveys – are biases really gender dependent?

    DEFF Research Database (Denmark)

    Ladenburg, Jacob; Olsen, Søren Bøye

    2010-01-01

    The potential for a number of common but severe biases in stated preference method surveys being gender dependent has been largely overlooked in the literature. In this paper we summarize results from three Choice Experiment studies that find evidence in favor of gender differences in vulnerability...

  10. Mood-congruent free recall bias in anxious individuals is not a consequence of response bias

    OpenAIRE

    Russo, Riccardo; Whittuck, Dora; Roberson, Debi; Dutton, Kevin; Georgiou, George; Fox, Elaine

    2006-01-01

    The status of mood-congruent free recall bias in anxious individuals was evaluated following incidental encoding of target words. Individuals with high and low levels of trait anxiety completed a modified Stroop task, which revealed an attentional bias for threat-related stimuli in anxious individuals. This group was significantly slower in naming the colour in which threat-related words were displayed compared to neutral words. In a subsequent free recall test for the words used in the modif...

  11. Response bias, weighting adjustments, and design effects in the Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS).

    Science.gov (United States)

    Kessler, Ronald C; Heeringa, Steven G; Colpe, Lisa J; Fullerton, Carol S; Gebler, Nancy; Hwang, Irving; Naifeh, James A; Nock, Matthew K; Sampson, Nancy A; Schoenbaum, Michael; Zaslavsky, Alan M; Stein, Murray B; Ursano, Robert J

    2013-12-01

    The Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS) is a multi-component epidemiological and neurobiological study designed to generate actionable recommendations to reduce US Army suicides and increase knowledge about determinants of suicidality. Three Army STARRS component studies are large-scale surveys: one of new soldiers prior to beginning Basic Combat Training (BCT; n = 50,765 completed self-administered questionnaires); another of other soldiers exclusive of those in BCT (n = 35,372); and a third of three Brigade Combat Teams about to deploy to Afghanistan who are being followed multiple times after returning from deployment (n = 9421). Although the response rates in these surveys are quite good (72.0-90.8%), questions can be raised about sample biases in estimating prevalence of mental disorders and suicidality, the main outcomes of the surveys based on evidence that people in the general population with mental disorders are under-represented in community surveys. This paper presents the results of analyses designed to determine whether such bias exists in the Army STARRS surveys and, if so, to develop weights to correct for these biases. Data are also presented on sample inefficiencies introduced by weighting and sample clustering and on analyses of the trade-off between bias and efficiency in weight trimming.

  12. Quantifying the media bias in intensity surveys: Lessons from the 2001 Bhuj, India, earthquake

    Science.gov (United States)

    Hough, S.E.; Pande, P.

    2007-01-01

    Many seismologists have looked at the 26 January 2001 Bhuj earthquake as a key modern calibration event that could be used to improve estimates of magnitudes of large historic mainshocks in stable continental regions. Since no instrumental data are available for important historic events such as the 1819 Allah Bund, India, and the 1811-1812 New Madrid, central U.S. mainshocks, calibration hinges on comparisons of the macroseismic effects of these earthquakes with those of comparable modern earthquakes for which a reliable, instrumentally determined moment magnitude is available. However, although such a comparison is conceptually straightforward, in practice it is complicated by potentially significant inconsistencies in methods used to quantify macroseismic effects in different regions and/or times. For the Bhuj earthquake, extensive intensity data sets have been compiled and published from both media accounts and detailed direct surveys. Comparing the two provides a quantification of the previously suspected media bias, whereby earthquake effects can be exaggerated in media accounts. This bias is a strong function of intensity level, with substantial bias at the highest shaking levels and significantly less bias at low intensities. Because only sparse documentary data are in general available for older historic earthquakes, the results of this study suggest that their inferred intensity distributions might be similarly biased. We further use the survey-based intensity values to develop a new relationship between intensities and ground motions.

  13. The 2dF Galaxy Redshift Survey: stochastic relative biasing between galaxy populations

    CERN Document Server

    Wild, V; Lahav, O; Conway, E; Maddox, S; Baldry, I K; Baugh, C M; Bland-Hawthorn, J; Bridges, T; Cannon, R; Cole, S; Colless, M; Collins, C; Couch, W; Dalton, G B; De Propris, R; Driver, S P; Efstathiou, G P; Ellis, Richard S; Frenk, C S; Glazebrook, K; Jackson, C; Lewis, I; Lumsden, S; Madgwick, D; Norberg, P; Peterson, B A; Sutherland, W; Taylor, K

    2004-01-01

    It is well known that the clustering of galaxies depends on galaxy type. Such relative bias complicates the inference of cosmological parameters from galaxy redshift surveys, and is a challenge to theories of galaxy formation and evolution. In this paper we perform a joint counts-in-cells analysis on galaxies in the 2dF Galaxy Redshift Survey, classified by both colour and spectral type, eta, as early or late type galaxies. We fit three different models of relative bias to the joint probability distribution of the cell counts, assuming Poisson sampling of the galaxy density field. We investigate the nonlinearity and stochasticity of the relative bias, with cubical cells of side 10Mpc \\leq L \\leq 45Mpc (h=0.7). Exact linear bias is ruled out with high significance on all scales. Power law bias gives a better fit, but likelihood ratios prefer a bivariate lognormal distribution, with a non-zero `stochasticity' - i.e. scatter that may result from physical effects on galaxy formation other than those from the loca...

  14. Spectroscopic failures in photometric redshift calibration: cosmological biases and survey requirements

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Carlos E. [KIPAC, Menlo Park; Huterer, Dragan [Michigan U.; Lin, Huan [Fermilab; Busha, Michael T. [Zurich U.; Wechsler, Risa H. [SLAC

    2014-10-11

    We use N-body-spectro-photometric simulations to investigate the impact of incompleteness and incorrect redshifts in spectroscopic surveys to photometric redshift training and calibration and the resulting effects on cosmological parameter estimation from weak lensing shear-shear correlations. The photometry of the simulations is modeled after the upcoming Dark Energy Survey and the spectroscopy is based on a low/intermediate resolution spectrograph with wavelength coverage of 5500{\\AA} < {\\lambda} < 9500{\\AA}. The principal systematic errors that such a spectroscopic follow-up encounters are incompleteness (inability to obtain spectroscopic redshifts for certain galaxies) and wrong redshifts. Encouragingly, we find that a neural network-based approach can effectively describe the spectroscopic incompleteness in terms of the galaxies' colors, so that the spectroscopic selection can be applied to the photometric sample. Hence, we find that spectroscopic incompleteness yields no appreciable biases to cosmology, although the statistical constraints degrade somewhat because the photometric survey has to be culled to match the spectroscopic selection. Unfortunately, wrong redshifts have a more severe impact: the cosmological biases are intolerable if more than a percent of the spectroscopic redshifts are incorrect. Moreover, we find that incorrect redshifts can also substantially degrade the accuracy of training set based photo-z estimators. The main problem is the difficulty of obtaining redshifts, either spectroscopically or photometrically, for objects at z > 1.3. We discuss several approaches for reducing the cosmological biases, in particular finding that photo-z error estimators can reduce biases appreciably.

  15. Measuring Implicit Sexual Response Biases to Nude Male and Female Pictures in Androphilic and Gynephilic Men

    OpenAIRE

    Timmins, Liam Eugene; Barnes-Holmes, Dermot; Cullen, Claire

    2016-01-01

    Snowden, Wichter, and Gray (2008) demonstrated that an Implicit Association Test and a Priming Task both predicted the sexual orientation of gynephilic and androphilic men in terms of their attraction biases towards pictures of nude males and females. For both measures, relative bias scores were obtained, with no information on the separate response biases to each target gender. The present study sought to extend this research by assessing both relative and individual implicit biases using th...

  16. Memory enhancement after drinking ethanol: consolidation, interference, or response bias?

    Science.gov (United States)

    Tyson, P D; Schirmuly, M

    1994-11-01

    One explanation for memory facilitation is that alcohol has a short-term neurochemical stimulating effect on consolidating neural networks when material is learned before drinking. Contrary to the consolidation hypothesis, when the consolidation interval was manipulated the results showed that the effects of alcohol were not time dependent. Compared to placebo subjects, alcohol significantly facilitated the recall of 25 words whether administered immediately or 40 min after learning. In addition, alcohol significantly increased the memory of words associated with pictures when incidentally learned before drinking and significantly decreased incidental learning after drinking. Another explanation for memory facilitation is that alcohol's depressive physiological effect impairs the acquisition of new information, like sleeping after learning, and enhances memory by reducing subsequent interference. Consistent with the retroactive interference hypothesis, the effects of alcohol reduced interpolated interference, were greater on recall than recognition, and were immune to time delays. Contemporary theories view memory enhancement attributed to alcohol as indirectly influencing response biases and contextual cues associated with retrieval from episodic memory.

  17. Effect of survey mode on response patterns

    DEFF Research Database (Denmark)

    Christensen, Anne Illemann; Ekholm, Ola; Glümer, Charlotte

    2014-01-01

    BACKGROUND: While face-to-face interviews are considered the gold standard of survey modes, self-administered questionnaires are often preferred for cost and convenience. This article examines response patterns in two general population health surveys carried out by face-to-face interview and self......-administered questionnaire, respectively. METHOD: Data derives from a health interview survey in the Region of Southern Denmark (face-to-face interview) and The Danish Health and Morbidity Survey 2010 (self-administered questionnaire). Identical questions were used in both surveys. Data on all individuals were obtained from...... administrative registers and linked to survey data at individual level. Multiple logistic regression analyses were used to examine the effect of survey mode on response patterns. RESULTS: The non-response rate was higher in the self-administered survey (37.9%) than in the face-to-face interview survey (23...

  18. Determinación de sesgo de no respuesta en una encuesta probabilística de hogares de comportamiento sexual con personas del mismo género Assessment of non-response bias in a probability household survey of male same-gender sexual behavior

    Directory of Open Access Journals (Sweden)

    José Antonio Izazola-Licea

    2000-04-01

    encuesta. La selección cuidadosa del personal de campo y la capacitación de los entrevistadores podría haber coadyuvado en minimizar el sesgo potencial.OBJECTIVE: To assess non-participation bias in a survey of male sexual behavior. MATERIAL AND METHODS: A household survey was carried out in 19921993 using a probability sampling frame in Mexico City. Demographic variables were available for all eligible men. The extent of non-participation bias was estimated using a version of the Heckman method, which utilizes two equations, one to predict participation and the other to predict reports of same-gender sexual behavior. RESULTS: A total of 8 068 of the 13 713 eligible men completed a face-to-face questionnaire (response rate 59%; 173 men (2.1% reported bisexual behavior in their lifetime, and 37 (0.4% reported only male partners. Survey participation was predicted using demographic variables: 67% of the observations were correctly predicted by a probit regression model: 82% of participants and 53% of non-participants (pseudo-r²=0.13. Same-gender sexual behavior was predicted by variables indicating attachment to gay/bisexual social networks, history of sexually transmitted diseases, positive attitudes towards gay and bisexual males, and lack of support from male relatives. Ninety-seven per cent of the cases was correctly predicted by the probit model (pseudo-r²=0.14. The correlation between these two equations was not statistically significant. CONCLUSIONS: These results indicate that prevalence estimates of same-gender sexual behavior among Mexico City men were not biased by selective survey participation. Careful selection and training of household interviewers may have assisted in minimizing potential bias.

  19. The MOSDEF Survey: AGN Multi-wavelength Identification, Selection Biases, and Host Galaxy Properties

    Science.gov (United States)

    Azadi, Mojegan; Coil, Alison L.; Aird, James; Reddy, Naveen; Shapley, Alice; Freeman, William R.; Kriek, Mariska; Leung, Gene C. K.; Mobasher, Bahram; Price, Sedona H.; Sanders, Ryan L.; Shivaei, Irene; Siana, Brian

    2017-01-01

    We present results from the MOSFIRE Deep Evolution Field (MOSDEF) survey on the identification, selection biases, and host galaxy properties of 55 X-ray, IR, and optically selected active galactic nuclei (AGNs) at 1.4optical spectra of galaxies and AGNs and use the BPT diagram to identify optical AGNs. We examine the uniqueness and overlap of the AGNs identified at different wavelengths. There is a strong bias against identifying AGNs at any wavelength in low-mass galaxies, and an additional bias against identifying IR AGNs in the most massive galaxies. AGN hosts span a wide range of star formation rates (SFRs), similar to inactive galaxies once stellar mass selection effects are accounted for. However, we find (at ∼2–3σ significance) that IR AGNs are in less dusty galaxies with relatively higher SFR and optical AGNs in dusty galaxies with relatively lower SFR. X-ray AGN selection does not display a bias with host galaxy SFR. These results are consistent with those from larger studies at lower redshifts. Within star-forming galaxies, once selection biases are accounted for, we find AGNs in galaxies with similar physical properties as inactive galaxies, with no evidence for AGN activity in particular types of galaxies. This is consistent with AGNs being fueled stochastically in any star-forming host galaxy. We do not detect a significant correlation between SFR and AGN luminosity for individual AGN hosts, which may indicate the timescale difference between the growth of galaxies and their supermassive black holes.

  20. Development and Validation of a Response Bias Scale (RBS) for the MMPI-2

    Science.gov (United States)

    Gervais, Roger O.; Ben-Porath, Yossef S.; Wygant, Dustin B.; Green, Paul

    2007-01-01

    This study describes the development of a Minnesota Multiphasic Personality Inventory (MMPI-2) scale designed to detect negative response bias in forensic neuropsychological or disability assessment settings. The Response Bias Scale (RBS) consists of 28 MMPI-2 items that discriminated between persons who passed or failed the Word Memory Test…

  1. A Misleading Review of Response Bias: Comment on McGrath, Mitchell, Kim, and Hough (2010)

    Science.gov (United States)

    Rohling, Martin L.; Larrabee, Glenn J.; Greiffenstein, Manfred F.; Ben-Porath, Yossef S.; Lees-Haley, Paul; Green, Paul; Greve, Kevin W.

    2011-01-01

    In the May 2010 issue of "Psychological Bulletin," R. E. McGrath, M. Mitchell, B. H. Kim, and L. Hough published an article entitled "Evidence for Response Bias as a Source of Error Variance in Applied Assessment" (pp. 450-470). They argued that response bias indicators used in a variety of settings typically have insufficient data to support such…

  2. Improving Survey Response Rates in Online Panels

    DEFF Research Database (Denmark)

    Pedersen, Mogens Jin; Nielsen, Christian Videbæk

    2016-01-01

    experiment among 6,162 members of an online survey panel, this article shows how low-cost incentives and cost-free text appeal interventions may impact the survey response rate in online panels. The experimental treatments comprise (a) a cash prize lottery incentive, (b) two donation incentives equating......Identifying ways to efficiently maximize the response rate to surveys is important to survey-based research. However, evidence on the response rate effect of donation incentives and especially altruistic and egotistic-type text appeal interventions is sparse and ambiguous. By a randomized survey...... survey response with a monetary donation to a good cause, (c) an egotistic-type text appeal, and (d) an altruistic-type text appeal. Relative to a control group, we find higher response rates among the recipients of the egotistic-type text appeal and the lottery incentive. Donation incentives yield lower...

  3. Surveys of Health Professions Trainees: Prevalence, Response Rates, and Predictive Factors to Guide Researchers.

    Science.gov (United States)

    Phillips, Andrew W; Friedman, Benjamin T; Utrankar, Amol; Ta, Andrew Q; Reddy, Shalini T; Durning, Steven J

    2017-02-01

    To establish a baseline overall response rate for surveys of health professions trainees, determine strategies associated with improved response rates, and evaluate for the presence of nonresponse bias. The authors performed a comprehensive analysis of all articles published in Academic Medicine, Medical Education, and Advances in Health Sciences Education in 2013, recording response rates. Additionally, they reviewed nonresponse bias analyses and factors suggested in other fields to affect response rate including survey delivery method, prenotification, and incentives. The search yielded 732 total articles; of these, 356 were research articles, and of these, 185 (52.0%) used at least one survey. Of these, 66 articles (35.6%) met inclusion criteria and yielded 73 unique surveys. Of the 73 surveys used, investigators reported a response rate for 63.0% of them; response rates ranged from 26.6% to 100%, mean (standard deviation) 71.3% (19.5%). Investigators reported using incentives for only 16.4% of the 73 surveys. The only survey methodology factor significantly associated with response rate was single- vs. multi-institutional surveys (respectively, 74.6% [21.2%] vs. 62.0% [12.8%], P = .022). Notably, statistical power for all analyses was limited. No articles evaluated for nonresponse bias. Approximately half of the articles evaluated used a survey as part of their methods. Limited data are available to establish a baseline response rate among health professions trainees and inform researchers which strategies are associated with higher response rates. Journals publishing survey-based health professions education research should improve reporting of response rate, nonresponse bias, and other survey factors.

  4. Publication bias in laboratory animal research: a survey on magnitude, drivers, consequences and potential solutions.

    Directory of Open Access Journals (Sweden)

    Gerben ter Riet

    Full Text Available CONTEXT: Publication bias jeopardizes evidence-based medicine, mainly through biased literature syntheses. Publication bias may also affect laboratory animal research, but evidence is scarce. OBJECTIVES: To assess the opinion of laboratory animal researchers on the magnitude, drivers, consequences and potential solutions for publication bias. And to explore the impact of size of the animals used, seniority of the respondent, working in a for-profit organization and type of research (fundamental, pre-clinical, or both on those opinions. DESIGN: Internet-based survey. SETTING: All animal laboratories in The Netherlands. PARTICIPANTS: Laboratory animal researchers. MAIN OUTCOME MEASURE(S: Median (interquartile ranges strengths of beliefs on 5 and 10-point scales (1: totally unimportant to 5 or 10: extremely important. RESULTS: Overall, 454 researchers participated. They considered publication bias a problem in animal research (7 (5 to 8 and thought that about 50% (32-70 of animal experiments are published. Employees (n = 21 of for-profit organizations estimated that 10% (5 to 50 are published. Lack of statistical significance (4 (4 to 5, technical problems (4 (3 to 4, supervisors (4 (3 to 5 and peer reviewers (4 (3 to 5 were considered important reasons for non-publication (all on 5-point scales. Respondents thought that mandatory publication of study protocols and results, or the reasons why no results were obtained, may increase scientific progress but expected increased bureaucracy. These opinions did not depend on size of the animal used, seniority of the respondent or type of research. CONCLUSIONS: Non-publication of "negative" results appears to be prevalent in laboratory animal research. If statistical significance is indeed a main driver of publication, the collective literature on animal experimentation will be biased. This will impede the performance of valid literature syntheses. Effective, yet efficient systems should be explored to

  5. The MOSDEF survey: AGN multi-wavelength identification, selection biases and host galaxy properties

    CERN Document Server

    Azadi, Mojegan; Aird, James; Reddy, Naveen; Shapley, Alice; Freeman, William R; Kriek, Mariska; Leung, Gene C K; Mobasher, Bahram; Price, Sedona H; Sanders, Ryan L; Shivaei, Irene; Siana, Brian

    2016-01-01

    We present results from the MOSFIRE Deep Evolution Field (MOSDEF) survey on the identification, selection biases and host galaxy properties of 55 X-ray, IR and optically-selected active galactic nuclei (AGN) at $1.4 < z < 3.8$. We obtain rest-frame optical spectra of galaxies and AGN and use the BPT diagram to identify optical AGN. We examine the uniqueness and overlap of the AGN identified at different wavelengths. There is a strong bias against identifying AGN at any wavelength in low mass galaxies, and an additional bias against identifying IR AGN in the most massive galaxies. AGN host galaxies span a wide range of star formation rate (SFR), similar to inactive galaxies once stellar mass selection effects are accounted for. However, we generally identify IR AGN in less dusty galaxies with relatively higher SFR and optical AGN in dusty galaxies with relatively lower SFR. X-ray AGN selection does not display a bias with host galaxy SFR. These results are consistent with those from larger studies at low...

  6. Self-reporting bias in Chinook salmon sport fisheries in Idaho: implications for roving creel surveys

    Science.gov (United States)

    McCormick, Joshua L.; Quist, Michael C.; Schill, Daniel J.

    2013-01-01

    Self-reporting bias in sport fisheries of Chinook Salmon Oncorhynchus tshawytscha in Idaho was quantified by comparing observed and angler-reported data. A total of 164 observed anglers fished for 541 h and caught 74 Chinook Salmon. Fifty-eight fish were harvested and 16 were released. Anglers reported fishing for 604 h, an overestimate of 63 h. Anglers reported catching 66 fish; four less harvested and four less released fish were reported than observed. A Monte Carlo simulation revealed that when angler-reported data were used, total catch was underestimated by 14–15 fish (19–20%) using the ratio-of-means estimator to calculate mean catch rate. Negative bias was reduced to six fish (8%) when the means-of-ratio estimator was used. Multiple linear regression models to predict reporting bias in time fished had poor predictive value. However, actual time fished and a categorical covariate indicating whether the angler fished continuously during their fishing trip were two variables that were present in all of the top a priori models evaluated. Underreporting of catch and overreporting of time fished by anglers present challenges when managing Chinook Salmon sport fisheries. However, confidence intervals were near target levels and using more liberal definitions of angling when estimating effort in creel surveys may decrease sensitivity to bias in angler-reported data.

  7. Response Bias on Self-Report Measures of Sexual Fantasies Among Sexual Offenders.

    Science.gov (United States)

    Seifert, Kindra; Boulas, Jenna; Huss, Matthew T; Scalora, Mario J

    2017-02-01

    The impact of sexual fantasies in future risk and treatment response among sexual offenders has long been known. However, as we develop objective self-report measures of sexual fantasies, response bias is becoming an increasing concern. In examining a sample of institutionalized sex offenders, the present study suggests that offenders' responses on these measures are prone to response bias, the bias does not negate their associations with other self-report measures of sexual deviance, and relationship of their sexual fantasies does not appear to relate to actual behavioral indications. Clinical and research implications for these findings are discussed.

  8. Responses to Sex-Bias Criticism in Cognitive Moral Theory.

    Science.gov (United States)

    Socoski, Patrick M.

    This paper explores the issue of sex bias in a contemporary major theory of moral development, cognitive moral theory. It explains critical reactions by Carol Gilligan and others questioning whether cognitive moral theory adequately accounts for female moral reasoning and behavior in its theory and research procedures. Several general…

  9. Real-time Analysis and Selection Biases in the Supernova Legacy Survey

    CERN Document Server

    Perrett, K; Sullivan, M; Pritchet, C; Conley, A; Carlberg, R; Astier, P; Balland, C; Basa, S; Fouchez, D; Guy, J; Hardin, D; Hook, I M; Howell, D A; Pain, R; Regnault, N

    2010-01-01

    The Supernova Legacy Survey (SNLS) has produced a high-quality, homogeneous sample of Type Ia supernovae (SNe Ia) out to redshifts greater than z=1. In its first four years of full operation (to June 2007), the SNLS discovered more than 3000 transient candidates, 373 of which have been confirmed spectroscopically as SNe Ia. Use of these SNe Ia in precision cosmology critically depends on an analysis of the observational biases incurred in the SNLS survey due to the incomplete sampling of the underlying SN Ia population. This paper describes our real-time supernova detection and analysis procedures, and uses detailed Monte Carlo simulations to examine the effects of Malmquist bias and spectroscopic sampling. Such sampling effects are found to become apparent at z~0.6, with a significant shift in the average magnitude of the spectroscopically confirmed SN Ia sample towards brighter values for z>0.75. We describe our approach to correct for these selection biases in our three-year SNLS cosmological analysis (SNL...

  10. Using key informant methods in organizational survey research: assessing for informant bias.

    Science.gov (United States)

    Hughes, L C; Preski, S

    1997-02-01

    Specification of variables that reflect organizational processes can add an important dimension to the investigation of outcomes. However, many contextual variables are conceptualized at a macro unit of analysis and may not be amenable to direct measurement. In these situations, proxy measurement is obtained by treating organizational members as key informants who report about properties of the work group or organization. Potential sources of bias when using key informant methods in organizational survey research are discussed. Statistical procedures for assessment of rater-trait interaction as a type of informant bias are illustrated using data from a study in which multiple key informants were sampled to obtain proxy measurement of the organizational climate for caring among baccalaureate schools of nursing.

  11. Hummingbird responses to gender-biased nectar production: are nectar biases maintained by natural or sexual selection?

    Science.gov (United States)

    Carlson, Jane E

    2008-01-01

    Pollinators mediate the evolution of secondary floral traits through both natural and sexual selection. Gender-biased nectar, for example, could be maintained by one or both, depending on the interactions between plants and pollinators. Here, I investigate pollinator responses to gender-biased nectar using the dichogamous herb Chrysothemis friedrichsthaliana (Gesneriaceae) which produces more nectar during the male floral phase. Previous research showed that the hummingbird pollinator Phaethornis striigularis visited male-phase flowers more often than female-phase flowers, and multiple visits benefited male more than female fecundity. If sexual selection maintains male-biased rewards, hummingbirds should prefer more-rewarding flowers independent of floral gender. If, however, differential rewards are partially maintained through natural selection, hummingbirds should respond to asymmetry with visits that reduce geitonogamy, i.e. selfing and pollen discounting. In plants with male biases, these visit types include single-flower visits and movements from low to high rewards. To test these predictions, I manipulated nectar asymmetry between pairs of real or artificial flowers on plants and recorded foraging behaviour. I also assessed maternal costs of selfing using hand pollinations. For plants with real flowers, hummingbirds preferred more-rewarding flowers and male-phase morphology, the latter possibly owing to previous experience. At artificial arrays, hummingbirds responded to extreme reward asymmetry with increased single-flower visits; however, they moved from high to low rewards more often than low to high. Finally, selfed flowers did not produce inferior seeds. In summary, sexual selection, more so than geitonogamy avoidance, maintains nectar biases in C. friedrichsthaliana, in one of the clearest examples of sexual selection in plants, to date. PMID:18460431

  12. A Critical Assessment of Bias in Survey Studies Using Location-Based Sampling to Recruit Patrons in Bars.

    Science.gov (United States)

    Morrison, Christopher; Lee, Juliet P; Gruenewald, Paul J; Marzell, Miesha

    2015-01-01

    Location-based sampling is a method to obtain samples of people within ecological contexts relevant to specific public health outcomes. Random selection increases generalizability; however, in some circumstances (such as surveying bar patrons), recruitment conditions increase risks of sample bias. We attempted to recruit representative samples of bars and patrons in six California cities, but low response rates precluded meaningful analysis. A systematic review of 24 similar studies revealed that none addressed the key shortcomings of our study. We recommend steps to improve studies that use location-based sampling: (i) purposively sample places of interest, (ii) use recruitment strategies appropriate to the environment, and (iii) provide full information on response rates at all levels of sampling.

  13. Dependence of CdTe response of bias history

    Energy Technology Data Exchange (ETDEWEB)

    Sites, J.R.; Sasala, R.A.; Eisgruber, I.L. [Colorado State Univ., Boulder, CO (United States)

    1995-11-01

    Several time-dependent effect have been observed in CdTe cells and modules in recent years. Some appear to be related to degradation at the back contact, some to changes in temperature at the thin-film junction, and some to the bias history of the cell or module. Back-contact difficulties only occur in some cases, and the other two effects are reversible. Nevertheless, confusion in data interpretation can arise when these effects are not characterized. This confusion can be particularly acute when more than one time-dependent effect occurs during the same measurement cycle. The purpose of this presentation is to help categorize time-dependent effects in CdTe and other thin-film cells to elucidate those related to bias history, and to note differences between cell and module analysis.

  14. [Base-rate estimates for negative response bias in a workers' compensation claim sample].

    Science.gov (United States)

    Merten, T; Krahi, G; Krahl, C; Freytag, H W

    2010-09-01

    Against the background of a growing interest in symptom validity assessment in European countries, new data on base rates of negative response bias is presented. A retrospective data analysis of forensic psychological evaluations was performed based on 398 patients with workers' compensation claims. 48 percent of all patients scored below cut-off in at least one symptom validity test (SVT) indicating possible negative response bias. However, different SVTs appear to have differing potential to identify negative response bias. The data point at the necessity to use modern methods to check data validity in civil forensic contexts.

  15. The effect of multiple reminders on response patterns in a Danish health survey

    DEFF Research Database (Denmark)

    Christensen, Anne I; Ekholm, Ola; Kristensen, Peter L;

    2015-01-01

    BACKGROUND: Reminders are routinely applied in surveys to increase response rates and reduce the possibility of bias. This study examines the effect of multiple reminders on the response rate, non-response bias, prevalence estimates and exposure-outcome relations in a national self......-administered health survey. METHODS: Data derive from the Danish National Health Survey 2010, in which 298 550 individuals (16 years of age or older) were invited to participate in a cross-sectional survey using a mixed-mode approach (paper and web questionnaires). At least two reminders were sent to non-respondents......, and 177 639 individuals completed the questionnaire (59.5%). Response patterns were compared between four groups of individuals (first mailing respondents, second mailing respondents, third mailing respondents and non-respondents). RESULTS: Multiple reminders led to an increase in response rate from 36...

  16. Objects in Kepler's Mirror May be Larger Than They Appear: Bias and Selection Effects in Transiting Planet Surveys

    CERN Document Server

    Gaidos, Eric

    2012-01-01

    Statistical analyses of large surveys for transiting planets such as the Kepler mission must account for systematic errors and biases. Transit detection depends not only on the planet's radius and orbital period, but also on host star properties. Thus, a sample of stars with transiting planets may not accurately represent the target population. Moreover, targets are selected using criteria such as a limiting apparent magnitude. These selection effects, combined with uncertainties in stellar radius, lead to biases in the properties of transiting planets and their host stars. We quantify possible biases in the Kepler survey. First, Eddington bias produced by a steep planet radius distribution and uncertainties in stellar radius results in a 15-20% overestimate of planet occurrence. Second, the magnitude limit of the Kepler target catalog induces Malmquist bias towards large, more luminous stars and underestimation of the radii of about one third of candidate planets, especially those larger than Neptune. Third,...

  17. Velocity Segregation and Systematic Biases In Velocity Dispersion Estimates with the SPT-GMOS Spectroscopic Survey

    Science.gov (United States)

    Bayliss, Matthew. B.; Zengo, Kyle; Ruel, Jonathan; Benson, Bradford A.; Bleem, Lindsey E.; Bocquet, Sebastian; Bulbul, Esra; Brodwin, Mark; Capasso, Raffaella; Chiu, I.-non; McDonald, Michael; Rapetti, David; Saro, Alex; Stalder, Brian; Stark, Antony A.; Strazzullo, Veronica; Stubbs, Christopher W.; Zenteno, Alfredo

    2017-03-01

    The velocity distribution of galaxies in clusters is not universal; rather, galaxies are segregated according to their spectral type and relative luminosity. We examine the velocity distributions of different populations of galaxies within 89 Sunyaev Zel’dovich (SZ) selected galaxy clusters spanning 0.28population. We find good agreement with simulations regarding the shape of the relationship between the measured velocity dispersion and the fraction of passive versus star-forming galaxies used to measure it, but we find a small offset between this relationship as measured in data and simulations, which suggests that our dispersions are systematically low by as much as 3% relative to simulations. We argue that this offset could be interpreted as a measurement of the effective velocity bias that describes the ratio of our observed velocity dispersions and the intrinsic velocity dispersion of dark matter particles in a published simulation result. Measuring velocity bias in this way suggests that large spectroscopic surveys can improve dispersion-based mass-observable scaling relations for cosmology even in the face of velocity biases, by quantifying and ultimately calibrating them out.

  18. Retrospective analysis of Mexican National Addictions Survey, 2008. Bias identification and correction.

    Directory of Open Access Journals (Sweden)

    Martín Romero-Martínez

    2013-05-01

    Full Text Available Objective. To determine the presence of bias on the estimation of the consumption sometime in life of alcohol, tobacco or illegal drugs and inhalable substances, and to propose a correction for this in the case it is present. Materials and methods. Mexican National Addictions Surveys (NAS 2002, 2008, and 2011 were analyzed to compare population estimations of consumption sometime in life of tobacco, alcohol or illegal drugs and inhalable substances. A couple of alternative approaches for bias correction were developed. Results. Estimated national prevalences of consumption sometime in life of alcohol and tobacco in the NAS 2008 are not plausible. There was no evidence of bias on the consumption sometime in life of illegal drugs and inhalable substances. New estimations for tobacco and alcohol consumption sometime in life were made, which resulted in plausible values when compared to other data available. Conclusion. Future analyses regarding tobacco and alcohol using NAS 2008 data will have to rely on these newly generated data weights, that are able to reproduce the new (plausible estimations.

  19. Power spectrum, correlation function, and tests for luminosity bias in the CfA redshift survey

    Science.gov (United States)

    Park, Changbom; Vogeley, Michael S.; Geller, Margaret J.; Huchra, John P.

    1994-01-01

    We describe and apply a method for directly computing the power spectrum for the galaxy distribution in the extension of the Center for Astrophysics Redshift Survey. Tests show that our technique accurately reproduces the true power spectrum for k greater than 0.03 h Mpc(exp -1). The dense sampling and large spatial coverage of this survey allow accurate measurement of the redshift-space power spectrum on scales from 5 to approximately 200 h(exp -1) Mpc. The power spectrum has slope n approximately equal -2.1 on small scales (lambda less than or equal 25 h(exp -1) Mpc) and n approximately -1.1 on scales 30 less than lambda less than 120 h(exp -1) Mpc. On larger scales the power spectrum flattens somewhat, but we do not detect a turnover. Comparison with N-body simulations of cosmological models shows that an unbiased, open universe CDM model (OMEGA h = 0.2) and a nonzero cosmological constant (CDM) model (OMEGA h = 0.24, lambda(sub zero) = 0.6, b = 1.3) match the CfA power spectrum over the wavelength range we explore. The standard biased CDM model (OMEGA h = 0.5, b = 1.5) fails (99% significance level) because it has insufficient power on scales lambda greater than 30 h(exp -1) Mpc. Biased CDM with a normalization that matches the Cosmic Microwave Background (CMB) anisotropy (OMEGA h = 0.5, b = 1.4, sigma(sub 8) (mass) = 1) has too much power on small scales to match the observed galaxy power spectrum. This model with b = 1 matches both Cosmic Background Explorer Satellite (COBE) and the small-scale power spect rum but has insufficient power on scales lambda approximately 100 h(exp -1) Mpc. We derive a formula for the effect of small-scale peculiar velocities on the power spectrum and combine this formula with the linear-regime amplification described by Kaiser to compute an estimate of the real-space power spectrum. Two tests reveal luminosity bias in the galaxy distribution: First, the amplitude of the pwer spectrum is approximately 40% larger for the brightest

  20. Velocity Segregation and Systematic Biases In Velocity Dispersion Estimates With the SPT-GMOS Spectroscopic Survey

    Energy Technology Data Exchange (ETDEWEB)

    Bayliss, Matthew.B. [MIT, MKI; Zengo, Kyle [Colby Coll.; Ruel, Jonathan [Harvard U., Phys. Dept.; Benson, Bradford A. [Fermilab; Bleem, Lindsey E. [Argonne; Bocquet, Sebastian [Argonne; Bulbul, Esra [MIT, MKI; Brodwin, Mark [Missouri U., Kansas City; Capasso, Raffaella [Munich, Tech. U., Universe; Chiu, I-non [Taiwan, Natl. Tsing Hua U.; McDonald, Michael [MIT, MKI; Rapetti, David [NASA, Ames; Saro, Alex [Munich, Tech. U., Universe; Stalder, Brian [Inst. Astron., Honolulu; Stark, Antony A. [Harvard-Smithsonian Ctr. Astrophys.; Strazzullo, Veronica [Munich, Tech. U., Universe; Stubbs, Christopher W. [Harvard-Smithsonian Ctr. Astrophys.; Zenteno, Alfredo [Cerro-Tololo InterAmerican Obs.

    2016-12-08

    The velocity distribution of galaxies in clusters is not universal; rather, galaxies are segregated according to their spectral type and relative luminosity. We examine the velocity distributions of different populations of galaxies within 89 Sunyaev Zel'dovich (SZ) selected galaxy clusters spanning $ 0.28 < z < 1.08$. Our sample is primarily draw from the SPT-GMOS spectroscopic survey, supplemented by additional published spectroscopy, resulting in a final spectroscopic sample of 4148 galaxy spectra---2868 cluster members. The velocity dispersion of star-forming cluster galaxies is $17\\pm4$% greater than that of passive cluster galaxies, and the velocity dispersion of bright ($m < m^{*}-0.5$) cluster galaxies is $11\\pm4$% lower than the velocity dispersion of our total member population. We find good agreement with simulations regarding the shape of the relationship between the measured velocity dispersion and the fraction of passive vs. star-forming galaxies used to measure it, but we find a small offset between this relationship as measured in data and simulations in which suggests that our dispersions are systematically low by as much as 3\\% relative to simulations. We argue that this offset could be interpreted as a measurement of the effective velocity bias that describes the ratio of our observed velocity dispersions and the intrinsic velocity dispersion of dark matter particles in a published simulation result. Measuring velocity bias in this way suggests that large spectroscopic surveys can improve dispersion-based mass-observable scaling relations for cosmology even in the face of velocity biases, by quantifying and ultimately calibrating them out.

  1. Extent, Awareness and Perception of Dissemination Bias in Qualitative Research: An Explorative Survey.

    Science.gov (United States)

    Toews, Ingrid; Glenton, Claire; Lewin, Simon; Berg, Rigmor C; Noyes, Jane; Booth, Andrew; Marusic, Ana; Malicki, Mario; Munthe-Kaas, Heather M; Meerpohl, Joerg J

    2016-01-01

    Qualitative research findings are increasingly used to inform decision-making. Research has indicated that not all quantitative research on the effects of interventions is disseminated or published. The extent to which qualitative researchers also systematically underreport or fail to publish certain types of research findings, and the impact this may have, has received little attention. A survey was delivered online to gather data regarding non-dissemination and dissemination bias in qualitative research. We invited relevant stakeholders through our professional networks, authors of qualitative research identified through a systematic literature search, and further via snowball sampling. 1032 people took part in the survey of whom 859 participants identified as researchers, 133 as editors and 682 as peer reviewers. 68.1% of the researchers said that they had conducted at least one qualitative study that they had not published in a peer-reviewed journal. The main reasons for non-dissemination were that a publication was still intended (35.7%), resource constraints (35.4%), and that the authors gave up after the paper was rejected by one or more journals (32.5%). A majority of the editors and peer reviewers "(strongly) agreed" that the main reasons for rejecting a manuscript of a qualitative study were inadequate study quality (59.5%; 68.5%) and inadequate reporting quality (59.1%; 57.5%). Of 800 respondents, 83.1% "(strongly) agreed" that non-dissemination and possible resulting dissemination bias might undermine the willingness of funders to support qualitative research. 72.6% and 71.2%, respectively, "(strongly) agreed" that non-dissemination might lead to inappropriate health policy and health care. The proportion of non-dissemination in qualitative research is substantial. Researchers, editors and peer reviewers play an important role in this. Non-dissemination and resulting dissemination bias may impact on health care research, practice and policy. More

  2. Black Twitter: A Response to Bias in Mainstream Media

    Directory of Open Access Journals (Sweden)

    Latoya A. Lee

    2017-03-01

    Full Text Available This paper seeks to shed light on the ways people of color, in the United States, are using social media to challenge racial bias. As part of this investigation, this paper draws on Critical Race Theory, Feminist Theory, and Digital New Media studies to examine the extent to which social media, while seen as a place for ‘play’ can also operate as a digital homespace, a space used as a tool for black women and men to (reconstruct their bodies and identities, challenging the “controlling images” widespread in mainstream media and society at large. This paper employs the methods of content analysis and participant observation and find that these social media forums are not transformative by themselves but instead have little moments that make for resistance and a digital homespace.

  3. Baboons' response speed is biased by their moods.

    Directory of Open Access Journals (Sweden)

    Yousri Marzouki

    Full Text Available The affect-as-information hypothesis (e.g., Schwarz & Clore, 2003, predicts that the positive or negative valence of our mood differentially affects our processing of the details of the environment. However, this hypothesis has only been tested with mood induction procedures and fairly complex cognitive tasks in humans. Here, six baboons (Papio papio living in a social group had free access to a computerized visual search task on which they were over-trained. Trials that immediately followed a spontaneously expressed emotional behavior were analyzed, ruling out possible biases due to induction procedures. RTs following negatively valenced behaviors are slower than those following neutral and positively valenced behaviors, respectively. Thus, moods affect the performance of nonhuman primates tested in highly automatized tasks, as it does in humans during tasks with much higher cognitive demands. These findings reveal a presumably universal and adaptive mechanism by which moods influence performance in various ecological contexts.

  4. 78 FR 45479 - Frequency Response and Frequency Bias Setting Reliability Standard

    Science.gov (United States)

    2013-07-29

    ... Energy Regulatory Commission 18 CFR Part 40 Frequency Response and Frequency Bias Setting Reliability...: The Commission proposes to approve Reliability Standard BAL- 003-1 (Frequency Response and Frequency... of frequency response needed for reliable operations for each Balancing Authority within...

  5. Survey of Munitions Response Technologies

    Science.gov (United States)

    2006-06-01

    distributed between two operators and tied with an umbilical cord. Man-portable platforms are also being developed using wireless technology to reduce the...munitions response (Lim 2004, Bucaro 2006, Lavely 2006, Carroll 2006). Models are being validated using data measured in tanks and ponds and in offshore

  6. Age-Related Response Bias in the Decoding of Sad Facial Expressions

    Directory of Open Access Journals (Sweden)

    Mara Fölster

    2015-10-01

    Full Text Available Recent studies have found that age is negatively associated with the accuracy of decoding emotional facial expressions; this effect of age was found for actors as well as for raters. Given that motivational differences and stereotypes may bias the attribution of emotion, the aim of the present study was to explore whether these age effects are due to response bias, that is, the unbalanced use of response categories. Thirty younger raters (19–30 years and thirty older raters (65–81 years viewed video clips of younger and older actors representing the same age ranges, and decoded their facial expressions. We computed both raw hit rates and bias-corrected hit rates to assess the influence of potential age-related response bias on decoding accuracy. Whereas raw hit rates indicated significant effects of both the actors’ and the raters’ ages on decoding accuracy for sadness, these age effects were no longer significant when response bias was corrected. Our results suggest that age effects on the accuracy of decoding facial expressions may be due, at least in part, to age-related response bias.

  7. Publication bias in laboratory animal research: a survey on magnitude, drivers, consequences and potential solutions

    NARCIS (Netherlands)

    Riet, G. ter; Korevaar, D.A.; Leenaars, M.; Sterk, P.J.; Noorden, C.J. van; Bouter, L.M.; Lutter, R.; Oude Elferink, R.P.; Hooft, L.

    2012-01-01

    CONTEXT: Publication bias jeopardizes evidence-based medicine, mainly through biased literature syntheses. Publication bias may also affect laboratory animal research, but evidence is scarce. OBJECTIVES: To assess the opinion of laboratory animal researchers on the magnitude, drivers, consequences a

  8. The usefulness of the Basic Question Procedure for determining non-response bias in substantive variables - A test of four telephone questionnaires

    NARCIS (Netherlands)

    van Goor, Henk; van Goor, Annemiek

    2007-01-01

    The Basic Question Procedure (BQP) is a method for determining non-response bias. The BQP involves asking one basic question - that is, the question relating to the central substantive variable of the study - of those persons who refuse to participate in the survey. We studied the usefulness of this

  9. Social Desirability, Non-Response Bias and Reliability in a Long Self-Report Measure: Illustrations from the MMPI-2 Administered to Brunei Student Teachers

    Science.gov (United States)

    Mundia, Lawrence

    2011-01-01

    The survey investigated the problems of social desirability (SD), non-response bias (NRB) and reliability in the Minnesota Multiphasic Personality Inventory--Revised (MMPI-2) self-report inventory administered to Brunei student teachers. Bruneians scored higher on all the validity scales than the normative US sample, thereby threatening the…

  10. Racial Bias in Neural Empathic Responses to Pain: e84001

    National Research Council Canada - National Science Library

    Luis Sebastian Contreras-Huerta; Katharine S Baker; Katherine J Reynolds; Luisa Batalha; Ross Cunnington

    2013-01-01

    ... of another racial group. The aim of the present study was to examine whether a more general social group category, other than race, could similarly modulate neural empathic responses and perhaps account for the apparent...

  11. Racial bias in neural empathic responses to pain

    National Research Council Canada - National Science Library

    Contreras-Huerta, Luis Sebastian; Baker, Katharine S; Reynolds, Katherine J; Batalha, Luisa; Cunnington, Ross

    2013-01-01

    ... of another racial group. The aim of the present study was to examine whether a more general social group category, other than race, could similarly modulate neural empathic responses and perhaps account for the apparent...

  12. Measuring Implicit Sexual Response Biases to Nude Male and Female Pictures in Androphilic and Gynephilic Men.

    Science.gov (United States)

    Timmins, Liam; Barnes-Holmes, Dermot; Cullen, Claire

    2016-05-01

    Snowden, Wichter, and Gray (2008) demonstrated that an Implicit Association Test and a Priming Task both predicted the sexual orientation of gynephilic and androphilic men in terms of their attraction biases towards pictures of nude males and females. For both measures, relative bias scores were obtained, with no information on the separate response biases to each target gender. The present study sought to extend this research by assessing both relative and individual implicit biases using the Implicit Relational Assessment Procedure (IRAP). An explicit measure screened for men with androphilic (n = 16) or gynephilic (n = 16) orientations on the dimensions of "sexual attraction," "sexual behavior," "sexual fantasies," "hetero/gay lifestyle," and "self identification." The IRAP involved responding "True" or "False" to pictures of nude males and females as either attractive or unattractive. Participants were required to respond in a manner consistent with their reported sexual orientation for half of the IRAP's test blocks and inconsistent for the other half. Response latencies were recorded and analyzed. The IRAP revealed a non-orthogonal pattern of biases across the two groups and had an excellent ability to predict sexual orientation with areas under the curves of 1.0 for the relative bias score and .94 and .95 for the bias scores for the male and female pictures, respectively. Correlations between the IRAP and explicit measures of sexual orientation were consistently high. The findings support the IRAP as a potentially valuable tool in the study of sexual preferences.

  13. Peculiar Velocities into the Next Generation: Cosmological Parameters From Large Surveys without Bias from Nonlinear Structure

    CERN Document Server

    Abate, Alexandra; Teodoro, Luis F A; Warren, Michael S; Hendry, Martin

    2008-01-01

    We investigate methods to best estimate the normalisation of the mass density fluctuation power spectrum (sigma_8) using peculiar velocity data from a survey like the Six degree Field Galaxy Velocity Survey (6dFGSv). We focus on two potential problems (i) biases from nonlinear growth of structure and (ii) the large number of velocities in the survey. Simulations of LambdaCDM-like models are used to test the methods. We calculate the likelihood from a full covariance matrix of velocities averaged in grid cells. This simultaneously reduces the number of data points and smooths out nonlinearities which tend to dominate on small scales. We show how the averaging can be taken into account in the predictions in a practical way, and show the effect of the choice of cell size. We find that a cell size can be chosen that significantly reduces the nonlinearities without significantly increasing the error bars on cosmological parameters. We compare our results with those from a principal components analysis following Wa...

  14. Assessing Underreporting Response Bias on the MMPI-2

    Science.gov (United States)

    Bagby, R. Michael; Marshall, Margarita B.

    2004-01-01

    The authors assess the replicability of the two-factor model of underreporting response style. They then examine the relative performance of scales measuring these styles in analog (ARD) and differential prevalence group (DPG) designs. Principal components analysis produced a two-factor structure corresponding to self-deceptive (SD) and impression…

  15. Assessing Underreporting Response Bias on the MMPI-2

    Science.gov (United States)

    Bagby, R. Michael; Marshall, Margarita B.

    2004-01-01

    The authors assess the replicability of the two-factor model of underreporting response style. They then examine the relative performance of scales measuring these styles in analog (ARD) and differential prevalence group (DPG) designs. Principal components analysis produced a two-factor structure corresponding to self-deceptive (SD) and impression…

  16. Extent, Awareness and Perception of Dissemination Bias in Qualitative Research: An Explorative Survey

    Science.gov (United States)

    Toews, Ingrid; Glenton, Claire; Lewin, Simon; Berg, Rigmor C.; Noyes, Jane; Booth, Andrew; Marusic, Ana; Malicki, Mario; Munthe-Kaas, Heather M.; Meerpohl, Joerg J.

    2016-01-01

    Background Qualitative research findings are increasingly used to inform decision-making. Research has indicated that not all quantitative research on the effects of interventions is disseminated or published. The extent to which qualitative researchers also systematically underreport or fail to publish certain types of research findings, and the impact this may have, has received little attention. Methods A survey was delivered online to gather data regarding non-dissemination and dissemination bias in qualitative research. We invited relevant stakeholders through our professional networks, authors of qualitative research identified through a systematic literature search, and further via snowball sampling. Results 1032 people took part in the survey of whom 859 participants identified as researchers, 133 as editors and 682 as peer reviewers. 68.1% of the researchers said that they had conducted at least one qualitative study that they had not published in a peer-reviewed journal. The main reasons for non-dissemination were that a publication was still intended (35.7%), resource constraints (35.4%), and that the authors gave up after the paper was rejected by one or more journals (32.5%). A majority of the editors and peer reviewers “(strongly) agreed” that the main reasons for rejecting a manuscript of a qualitative study were inadequate study quality (59.5%; 68.5%) and inadequate reporting quality (59.1%; 57.5%). Of 800 respondents, 83.1% “(strongly) agreed” that non-dissemination and possible resulting dissemination bias might undermine the willingness of funders to support qualitative research. 72.6% and 71.2%, respectively, “(strongly) agreed” that non-dissemination might lead to inappropriate health policy and health care. Conclusions The proportion of non-dissemination in qualitative research is substantial. Researchers, editors and peer reviewers play an important role in this. Non-dissemination and resulting dissemination bias may impact on

  17. Convergence among Data Sources, Response Bias, and Reliability and Validity of a Structured Job Analysis Questionnaire.

    Science.gov (United States)

    Smith, Jack E.; Hakel, Milton D.

    1979-01-01

    Examined are questions pertinent to the use of the Position Analysis Questionnaire: Who can use the PAQ reliably and validly? Must one rely on trained job analysts? Can people having no direct contact with the job use the PAQ reliably and validly? Do response biases influence PAQ responses? (Author/KC)

  18. Response bias-related impairment of early subjective face discrimination in social anxiety disorders: An event-related potential study.

    Science.gov (United States)

    Qi, Yanyan; Gu, Ruolei; Cao, Jianqin; Bi, Xuejing; Wu, Haiyan; Liu, Xun

    2017-02-05

    Considerable research has shown that social anxiety disorder (SAD) is accompanied by various negative cognitive biases, such as social feedback expectancy bias, memory bias, and interpretation bias. However, whether the memory bias in individuals with SAD is actually a manifestation of response bias, and whether such response bias is associated with deficits in face discrimination, remains unclear. In the present study, we investigated response bias (i.e., a tendency to recognize more negative evaluations) to faces with positive (social acceptance) or negative (social rejection) social evaluations in individuals with SAD and healthy controls (HCs) using event-related potentials (ERPs). Behavioral results revealed significant group differences in response bias in the forced-choice recall task, but no difference in overall memory accuracy. ERP results demonstrated that HCs showed a larger N170 to faces that had rejected them as compared to those that had accepted them, but this effect was not evident in the SAD group. Further analysis showed that response bias was correlated with the ΔN170 (rejected - accepted) amplitude. We concluded that the response bias in individuals with SAD is resulted from impairments in early discrimination of social faces, as reflected by the absent early N170 differentiation effect, which was associated with their combined negative biases.

  19. Nonlinear Response of Unbiased and Biased Bilayer Graphene at Terahertz Frequencies

    Science.gov (United States)

    McGouran, Riley

    The main focus of this thesis is the investigation of the nonlinear response of unbiased and biased bilayer graphene to incident radiation at terahertz frequencies. We present a tight-binding model of biased and unbiased bilayer graphene that is used to calculate the nonlinear terahertz response. Dynamic equations are developed for the electron density matrix within the length gauge. These equations facilitate the calculation of interband and intraband carrier dynamics. We then obtain nonlinear transmitted and reflected terahertz fields using the calculated nonlinear interband and intraband current densities. We examine the nonlinear response of unbiased bilayer graphene as a function of the incident field amplitude. In this case the sample is taken to be undoped. In the reflected field, we find the maximum third harmonic amplitude to be approximately 30% of the fundamental frequency for an incident field of 1.5 kV cm-1, which is greater than that found in undoped monolayer graphene at the same field amplitude. To examine the nonlinear response of biased bilayer graphene, we investigate two different scenarios. In the first scenario, we consider an undoped sample at fixed temperature. We find that when the external bias has a value of 2 meV, the generated third harmonic in the reflected field is approximately 45% of the fundamental for an incident field amplitude of 2 kV cm-1 . When we increase the external bias further to 8 meV, we find the generated third harmonic field is approximately 38% of the fundamental for an incident field amplitude of 1 kV cm-1. For both of these bias values, the generated third harmonic is greater than that found in undoped monolayer graphene. In that system, the generated third harmonic field is approximately 32% of the fundamental for an incident field amplitude of 200 V cm-1. In the second scenario, we consider doped biased bilayer graphene. We fix the carrier density at 2x1012 cm-2, the incident field amplitude at 50 kV cm-1, and

  20. The VIMOS Public Extragalactic Redshift Survey (VIPERS). Hierarchical scaling and biasing

    Science.gov (United States)

    Cappi, A.; Marulli, F.; Bel, J.; Cucciati, O.; Branchini, E.; de la Torre, S.; Moscardini, L.; Bolzonella, M.; Guzzo, L.; Abbas, U.; Adami, C.; Arnouts, S.; Bottini, D.; Coupon, J.; Davidzon, I.; De Lucia, G.; Fritz, A.; Franzetti, P.; Fumana, M.; Garilli, B.; Granett, B. R.; Ilbert, O.; Iovino, A.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; McCracken, H. J.; Paioro, L.; Polletta, M.; Pollo, A.; Scodeggio, M.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Burden, A.; Di Porto, C.; Marchetti, A.; Marinoni, C.; Mellier, Y.; Nichol, R. C.; Peacock, J. A.; Percival, W. J.; Phleps, S.; Schimd, C.; Schlagenhaufer, H.; Wolk, M.; Zamorani, G.

    2015-07-01

    Aims: Building on the two-point correlation function analyses of the VIMOS Public Extragalactic Redshift Survey (VIPERS), we investigate the higher-order correlation properties of the same galaxy samples to test the hierarchical scaling hypothesis at z ~ 1 and the dependence on galaxy luminosity, stellar mass, and redshift. With this work we also aim to assess possible deviations from the linearity of galaxy bias independently from a previously performed analysis of our survey. Methods: We have measured the count probability distribution function in spherical cells of varying radii (3 ≤ R ≤ 10 h-1 Mpc), deriving σ8g (the galaxy rms at 8 h-1 Mpc), the volume-averaged two-, three-, and four-point correlation functions and the normalized skewness S3g and kurtosis S4g for different volume-limited subsamples, covering the following ranges: -19.5 ≤ MB(z = 1.1) - 5log (h) ≤ -21.0 in absolute magnitude, 9.0 ≤ log (M∗/M⊙h-2) ≤ 11.0 in stellar mass, and 0.5 ≤ zfollowing. 1) The hierarchical scaling between the volume-averaged two- and three-point and two- and four-point correlation functions holds throughout the whole range of scale and redshift we could test. 2) We do not find a significant dependence of S3g on luminosity (below z = 0.9 the value of S3g decreases with luminosity, but only at 1σ-level). 3) We do not detect a significant dependence of S3g and S4g on scale, except beyond z ~ 0.9, where S3g and S4g have higher values on large scales (R ≥ 10 h-1 Mpc): this increase is mainly due to one of the two CFHTLS Wide Fields observed by VIPERS and can be explained as a consequence of sample variance, consistently with our analysis of mock catalogs. 4) We do not detect a significant evolution of S3g and S4g with redshift (apart from the increase of their values with scale in the last redshift bin). 5) σ8g increases with luminosity, but does not show significant evolution with redshift. As a consequence, the linear bias factor b = σ8g/σ8m, where σ8

  1. Interpretation bias in responses to ambiguous cues in pain patients.

    Science.gov (United States)

    Pincus, T; Pearce, S; McClelland, A; Farley, S; Vogel, S

    1994-05-01

    Pain patients and control subjects responses to ambiguous cues were compared in two separate investigations. In the first, pain patients, control subjects and physiotherapists were asked to produce a list of spontaneous associations to ambiguous cues (such as terminal and growth). To control for mood effects the experiment was repeated with three more groups: Pain patients, osteopaths and a control group. Measures of anxiety and depression were incorporated in the analysis. Results indicate that pain patients systematically produce more pain related associations than the other groups, and that this effect is independent of anxiety and depression levels. The discussion concentrates on the implications of these findings both for the theory of pain processing and for clinical interventions.

  2. A gender bias in the calcification response to ocean acidification

    Science.gov (United States)

    Holcomb, M.; Cohen, A. L.; McCorkle, D. C.

    2011-08-01

    The effects of nutrients and pCO2 on zooxanthellate and azooxanthellate colonies of the temperate scleractinian coral Astrangia poculata (Ellis and Solander, 1786) were investigated at two different temperatures (16 °C and 24 °C). Corals exposed to elevated pCO2 tended to have lower relative calcification rates, as estimated from changes in buoyant weights. No nutrient effect was observed. At 16 °C, gamete release was not observed, and no gender differences in calcification rate were observed. However, corals grown at 24 °C spawned repeatedly and male and female corals exhibited two different growth rate patterns. Female corals grown at 24 °C and exposed to CO2 had calcification rates 39 % lower than females grown at ambient CO2, while males showed only a 5 % decline in calcification under elevated CO2. At 16 °C, female and male corals showed similar reductions in calcification rates in response to elevated CO2 (15 % and 19 % respectively). At 24 °C, corals spawned repeatedly, while no spawning was observed at 16 °C. The increased sensitivity of females to elevated pCO2 may reflect a greater investment of energy in reproduction (egg production) relative to males (sperm production). These results suggest that both gender and spawning are important factors in determining the sensitivity of corals to ocean acidification and their inclusion in future research may be critical to predicting how the population structures of marine calcifiers will change in response to ocean acidification.

  3. Mechanism of the Pyroelectric Response under Direct-Current Bias in La-Modified Lead Zirconate Titanate Stannate Ceramics

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hong-Ling; WANG Gen-Shui; CHEN Xue-Feng; CAO Fei; DONG Xian-Lin; GU Yan; HE Hong-Liang; LIU Yu-Sheng

    2011-01-01

    Dielectric and pyroelectric properties ofPbo.97Lao.o2(Zro.42Sno.4oTio.i8)03 ceramics are investigated as functions of temperature and dc bias field. Induced and intrinsic pyroelectric coefficients pind and p0 are calculated and analyzed. It is found that the sign, value and variation of the net pyroelectric coefficient p with increasing dc bias all are dominated by p0 under applied biases. Polarization and depolarization processes under dc biases are analyzed. Besides the contribution of pind, the diffuse and decreased pyroelectric response under dc bias compared with that of an identical Geld poled sample without dc bias is mainly attributed to the depolarization process under dc bias.%@@ Dielectric and pyroelectric properties of Pbo.s7Lao.o2(Zro.42Sno.4OTio.is)O3 ceramics are investigated as functions of temperature and do bias field.Induced and intrinsic pyroelectric coefficients pind and p0 are calculated and analyzed.It is found that the sign,value and variation of the net pyroelectric coefficient p with increasing dc bias all are dominated by p0 under applied biases.Polarization and depolarization processes under do biases are analyzed.Besides the contribution of pind,the diffuse and decreased pyroelectric response under do bias compared with that of an identical field poled sample without do bias is mainly attributed to the depolarization process under do bias.

  4. Gender-biased behavior at work: what can surveys tell us about the link between sexual harassment and gender discrimination?

    OpenAIRE

    Antecol, Heather; Barcus, Vanessa E.; Cobb-Clark, Deborah A.

    2007-01-01

    This paper examines the links between survey-based reports of sexual harassment and gender discrimination. In particular, we are interested in assessing whether these concepts measure similar forms of gender-biased behavior and whether they have the same effect on workers' job satisfaction and intentions to leave their jobs. Our results provide little support for the notion that survey-based measures of sexual harassment and gender discrimination capture the same underlying behavior. Responde...

  5. Reexamining traditional issues in survey research: Just how evil is the anathema of low response rate?

    Energy Technology Data Exchange (ETDEWEB)

    Clark, S.B. [Oak Ridge Institute for Science and Education, TN (United States). Science/Engineering Education Division; Boser, J.A. [Univ. of Tennessee, Knoxville, TN (United States)

    1995-08-01

    Survey researchers have long been exhorted to strive for high response rates in order to maximize the likelihood that the respondents are representative of the population being surveyed. It is not surprising then, that much survey research has been directed towards examining the effects of various manipulatable factors on response rate. It is clear that attempts to reach the goal of minimizing the likelihood of nonresponse bias through testing various methods of increasing survey response rates have consumed much research and debate. The results obtained in this research have been inconsistent. Some studies have found significant differences, others have found none. The present study was designed to determine the extent to which the results of an employment survey of former graduates of a teacher preparation program would have been affected by changes in response rate.

  6. Elementary Pre-Service Teachers' Response-Shift Bias: Self-efficacy and attitudes toward science

    Science.gov (United States)

    Cartwright, Tina J.; Atwood, Jon

    2014-09-01

    Response-shift bias occurs when participants' initial constructs, such as self-efficacy in teaching science, are incomplete because they do not fully conceptualize something they have yet to experience. This study examines whether elementary pre-service teachers can consistently evaluate constructs such as self-efficacy and attitudes toward science throughout an elementary methods course. After the administration of traditional pre-tests, retrospective pre-tests, and post-tests, this study examined whether a response-shift bias consistently occurred in scales indicating science teaching self-efficacy (as measured by the Science Teaching Efficacy Beliefs Instrument-B), attitudes toward science (modified Attitudes Toward Science Inventory), and relevancy of science (Changes in Attitudes about the Relevancy of Science). Results indicate that a significant response-shift bias occurred in the scales relating to self-efficacy, confidence, and attitudes toward science; while no response-shift bias occurred in scales relating to outcome expectancy, value, and relevancy of science. Our data provide evidence that response-shifts naturally discriminate among different constructs and that participants successfully and consistently reported certain constructs over time which may be of interest for program evaluators and self-efficacy researchers. This research could have implications for program evaluators and researchers who need to measure program impacts on pre-service teachers with limited science-teaching experiences.

  7. Detecting subtle expressions: older adults demonstrate automatic and controlled positive response bias in emotional perception.

    Science.gov (United States)

    Johnson, Dan R; Whiting, Wythe L

    2013-03-01

    The present study examined age differences in emotional perception for the detection of low-intensity, single-emotion facial expressions. Confirming the "positivity effect," at 60 ms and 2,000 ms presentation rates older adults (age = 61+ years, n = 39) exhibited a response bias favoring happy over neutral responses, whereas younger adults (age = 18-23 years, n = 40) favored neutral responses. Furthermore, older adults favored neutral over fearful responses at the 60 ms presentation rate, relative to younger adults. The finding that age differences in response bias were most pronounced at the 60 ms versus 2,000 ms presentation rate suggests that positivity effects in emotional perception rely partly on automatic processing.

  8. Accuracy of responses from postal surveys about continuing medical education and information behavior: experiences from a survey among German diabetologists

    Directory of Open Access Journals (Sweden)

    Trelle Sven

    2002-08-01

    Full Text Available Abstract Background Postal surveys are a popular instrument for studies about continuing medical education habits. But little is known about the accuracy of responses in such surveys. The objective of this study was to quantify the magnitude of inaccurate responses in a postal survey among physicians. Methods A sub-analysis of a questionnaire about continuing medical education habits and information management was performed. The five variables used for the quantitative analysis are based on a question about the knowledge of a fictitious technical term and on inconsistencies in contingency tables of answers to logically connected questions. Results Response rate was 52%. Non-response bias is possible but seems not very likely since an association between demographic variables and inconsistent responses could not be found. About 10% of responses were inaccurate according to the definition. Conclusion It was shown that a sub-analysis of a questionnaire makes a quantification of inaccurate responses in postal surveys possible. This sub-analysis revealed that a notable portion of responses in a postal survey about continuing medical education habits and information management was inaccurate.

  9. Negative valence can evoke a liberal response bias in syllogistic reasoning.

    Science.gov (United States)

    Vartanian, Oshin; Nakashima, Ann; Bouak, Fethi; Smith, Ingrid; Baranski, Joseph V; Cheung, Bob

    2013-03-01

    Recently, studies have demonstrated that negative valence reduces the magnitude of the belief-bias effect in syllogistic reasoning. This effect has been localized in the reasoning stage, in the form of increased deliberation on trials where validity and conclusion believability are incongruent. Here, using signal detection theory, we show that the attenuation of belief bias observed when valence was negative can also be evoked by a liberal response bias at the decision stage. Indeed, when valence was negative participants adopted a more liberal criterion for judging syllogisms as "valid," and were overconfident in their judgments. They also displayed less sensitivity in distinguishing between valid and invalid syllogisms. Our findings dovetail with recent evidence from memory research suggesting that negative valence can evoke a liberal response bias without improving performance. Our novel contribution is the demonstration that the attenuating effect of negative valence on belief bias can take multiples routes--by influencing the decision stage as was the case here, the reasoning stage as has been demonstrated elsewhere, and potentially both stages.

  10. Maximising response rates in household telephone surveys

    Directory of Open Access Journals (Sweden)

    Sinclair Martha

    2008-11-01

    Full Text Available Abstract Background Epidemiological and other studies that require participants to respond by completing a questionnaire face the growing threat of non-response. Response rates to household telephone surveys are diminishing because of changes in telecommunications, marketing and culture. Accordingly, updated information is required about the rate of telephone listing in directories and optimal strategies to maximise survey participation. Methods A total of 3426 households in Sydney, Australia were approached to participate in a computer assisted telephone interview (CATI regarding their domestic (recycled and/or drinking water usage. Only randomly selected households in the suburb and postcode of interest with a telephone number listed in the Electronic White Pages (EWP that matched Australian electoral records were approached. Results The CATI response rate for eligible households contacted by telephone was 39%. The rate of matching of electoral and EWP records, a measure of telephone directory coverage, was 55%. Conclusion The use of a combination of approaches, such as an advance letter, interviewer training, establishment of researcher credentials, increasing call attempts and targeted call times, remains a good strategy to maximise telephone response rates. However, by way of preparation for future technological changes, reduced telephone number listings and people's increasing resistance to unwanted phone calls, alternatives to telephone surveys, such as internet-based approaches, should be investigated.

  11. Maximising response rates in household telephone surveys.

    Science.gov (United States)

    O'Toole, Joanne; Sinclair, Martha; Leder, Karin

    2008-11-03

    Epidemiological and other studies that require participants to respond by completing a questionnaire face the growing threat of non-response. Response rates to household telephone surveys are diminishing because of changes in telecommunications, marketing and culture. Accordingly, updated information is required about the rate of telephone listing in directories and optimal strategies to maximise survey participation. A total of 3426 households in Sydney, Australia were approached to participate in a computer assisted telephone interview (CATI) regarding their domestic (recycled and/or drinking) water usage. Only randomly selected households in the suburb and postcode of interest with a telephone number listed in the Electronic White Pages (EWP) that matched Australian electoral records were approached. The CATI response rate for eligible households contacted by telephone was 39%. The rate of matching of electoral and EWP records, a measure of telephone directory coverage, was 55%. The use of a combination of approaches, such as an advance letter, interviewer training, establishment of researcher credentials, increasing call attempts and targeted call times, remains a good strategy to maximise telephone response rates. However, by way of preparation for future technological changes, reduced telephone number listings and people's increasing resistance to unwanted phone calls, alternatives to telephone surveys, such as internet-based approaches, should be investigated.

  12. Physiological Response and Childhood Anxiety: Association With Symptoms of Anxiety Disorders and Cognitive Bias

    Science.gov (United States)

    Weems, Carl F.; Zakem, Alan H.; Costa, Natalie M.; Cannon, Melinda F.; Watts, Sarah E.

    2005-01-01

    This study examined the physiological response (skin conductance and heart rate [HR]) of youth exposed to a mildly phobic stimulus (video of a large dog) and its relation to child- and parent-reported anxiety symptoms and cognitive bias in a community-recruited sample of youth (n = 49). The results of this study indicated that HR and…

  13. Bias Errors due to Leakage Effects When Estimating Frequency Response Functions

    Directory of Open Access Journals (Sweden)

    Andreas Josefsson

    2012-01-01

    Full Text Available Frequency response functions are often utilized to characterize a system's dynamic response. For a wide range of engineering applications, it is desirable to determine frequency response functions for a system under stochastic excitation. In practice, the measurement data is contaminated by noise and some form of averaging is needed in order to obtain a consistent estimator. With Welch's method, the discrete Fourier transform is used and the data is segmented into smaller blocks so that averaging can be performed when estimating the spectrum. However, this segmentation introduces leakage effects. As a result, the estimated frequency response function suffers from both systematic (bias and random errors due to leakage. In this paper the bias error in the H1 and H2-estimate is studied and a new method is proposed to derive an approximate expression for the relative bias error at the resonance frequency with different window functions. The method is based on using a sum of real exponentials to describe the window's deterministic autocorrelation function. Simple expressions are derived for a rectangular window and a Hanning window. The theoretical expressions are verified with numerical simulations and a very good agreement is found between the results from the proposed bias expressions and the empirical results.

  14. Physiological Response and Childhood Anxiety: Association With Symptoms of Anxiety Disorders and Cognitive Bias

    Science.gov (United States)

    Weems, Carl F.; Zakem, Alan H.; Costa, Natalie M.; Cannon, Melinda F.; Watts, Sarah E.

    2005-01-01

    This study examined the physiological response (skin conductance and heart rate [HR]) of youth exposed to a mildly phobic stimulus (video of a large dog) and its relation to child- and parent-reported anxiety symptoms and cognitive bias in a community-recruited sample of youth (n = 49). The results of this study indicated that HR and…

  15. Objects in Kepler's Mirror May be Larger Than They Appear: Bias and Selection Effects in Transiting Planet Surveys

    Science.gov (United States)

    Gaidos, Eric; Mann, Andrew W.

    2013-01-01

    Statistical analyses of large surveys for transiting planets such as the Kepler mission must account for systematic errors and biases. Transit detection depends not only on the planet's radius and orbital period, but also on host star properties. Thus, a sample of stars with transiting planets may not accurately represent the target population. Moreover, targets are selected using criteria such as a limiting apparent magnitude. These selection effects, combined with uncertainties in stellar radius, lead to biases in the properties of transiting planets and their host stars. We quantify possible biases in the Kepler survey. First, Eddington bias produced by a steep planet radius distribution and uncertainties in stellar radius results in a 15%-20% overestimate of planet occurrence. Second, the magnitude limit of the Kepler target catalog induces Malmquist bias toward large, more luminous stars and underestimation of the radii of about one-third of candidate planets, especially those larger than Neptune. Third, because metal-poor stars are smaller, stars with detected planets will be very slightly (target average. Fourth, uncertainties in stellar radii produce correlated errors in planet radius and stellar irradiation. A previous finding, that highly irradiated giants are more likely to have "inflated" radii, remains significant, even accounting for this effect. In contrast, transit depth is negatively correlated with stellar metallicity even in the absence of any intrinsic correlation, and a previous claim of a negative correlation between giant planet transit depth and stellar metallicity is probably an artifact.

  16. Two components in IOR: evidence for response bias and perceptual processing delays using the SAT methodology.

    Science.gov (United States)

    Zhao, Yuanyuan; Heinke, Dietmar; Ivanoff, Jason; Klein, Raymond M; Humphreys, Glyn W

    2011-10-01

    Inhibition of return (IOR) occurs when reaction times (RTs) are slowed to respond to a target that appears at a previously attended location. We used the speed-accuracy trade-off (SAT) procedure to obtain conjoint measures of IOR on sensitivity and processing speed by presenting targets at cued and uncued locations. The results showed that IOR is associated with both delays in processing speed and shifts in response criterion. When the target was briefly presented, the results supported a criterion shift account of IOR. However, when the target was presented until response, the evidence indicated that, in addition to a response bias effect, there was an increase in the minimal time required for information about the target to accumulate above chance level. A hybrid account of IOR is suggested that describes effects on both response bias and perceptual processing.

  17. Aniseikonia Tests: The Role of Viewing Mode, Response Bias, and Size–Color Illusions

    Science.gov (United States)

    García-Pérez, Miguel A.; Peli, Eli

    2015-01-01

    Purpose: To identify the factors responsible for the poor validity of the most common aniseikonia tests, which involve size comparisons of red–green stimuli presented haploscopically. Methods: Aniseikonia was induced by afocal size lenses placed before one eye. Observers compared the sizes of semicircles presented haploscopically via color filters. The main factor under study was viewing mode (free viewing versus short presentations under central fixation). To eliminate response bias, a three-response format allowed observers to respond if the left, the right, or neither semicircle appeared larger than the other. To control decisional (criterion) bias, measurements were taken with the lens-magnified stimulus placed on the left and on the right. To control for size–color illusions, measurements were made with color filters in both arrangements before the eyes and under binocular vision (without color filters). Results: Free viewing resulted in a systematic underestimation of lens-induced aniseikonia that was absent with short presentations. Significant size–color illusions and decisional biases were found that would be mistaken for aniseikonia unless appropriate action is taken. Conclusions: To improve their validity, aniseikonia tests should use short presentations and include control conditions to prevent contamination from decisional/response biases. If anaglyphs are used, presence of size–color illusions must be checked for. Translational relevance: We identified optimal conditions for administration of aniseikonia tests and appropriate action for differential diagnosis of aniseikonia in the presence of response biases or size–color illusions. Our study has clinical implications for aniseikonia management. PMID:26101722

  18. Modifications of some simple One-stage Randomized Response Models to Two-stage in complex surveys

    Directory of Open Access Journals (Sweden)

    Mohammad Rafiq

    2016-06-01

    Full Text Available Warner (1965 introduced a Randomized Response Technique (RRT to minimize bias due to non- response or false response. Thereafter, several researchers have made significant contribution in the development and modification of different Randomized Response Models. We have modified a few one-stage Simple Randomized Response Models to two-stage randomized response models in complex surveys and found that our developed models are more efficient.

  19. Sex-different response in growth traits to resource heterogeneity explains male-biased sex ratio

    Science.gov (United States)

    Matsushita, Michinari; Takao, Mikako; Makita, Akifumi

    2016-08-01

    In dioecious plants, differences in growth traits between sexes in a response to micro-environmental heterogeneity may affect sex ratio bias and spatial distributions. Here, we examined sex ratios, stem growth traits and spatial distribution patterns in the dioecious clonal shrub Aucuba japonica var. borealis, in stands with varying light intensities. We found that male stems were significantly more decumbent (lower height/length ratio) but female stems were upright (higher height/length ratio). Moreover, we found sex-different response in stem density (no. of stems per unit area) along a light intensity gradient; in males the stem density increased with increases in canopy openness, but not in females. The higher sensitivity of males in increasing stem density to light intensity correlated with male-biased sex ratio; fine-scale sex ratio was strongly male-biased as canopy openness increased. There were also differences between sexes in spatial distributions of stems. Spatial segregation of sexes and male patches occupying larger areas than female patches might result from vigorous growth of males under well-lit environments. In summary, females and males showed different growth responses to environmental variation, and this seemed to be one of possible causes for the sex-differential spatial distributions and locally biased sex ratios.

  20. Patient race and perceived illness responsibility: effects on provider helping and bias.

    Science.gov (United States)

    Nazione, Samantha; Silk, Kami J

    2013-08-01

    Health care disparities represent a major issue impacting the quality of care in the USA. Provider biases have been identified as contributing to health care disparities. This study examined the helping intentions and biases reported by medical students based on patient race and perceived patient responsibility. The study was guided by the responsibility-affect-helping model (RAHM), which proposes that helping behaviour is a function of perceived responsibility and affect. In a 2 × 3 online experiment, medical students (n = 231) viewed a health chart and dialogue for either a Black or a White patient, in which the dialogue included a manipulation of the patient's rationales for his non-compliance with diet recommendations (responsible, not responsible, no responsibility assigned). After viewing the manipulation, medical students completed measures regarding perceived patient responsibility, affect, intention to help, perceptions of the patient and ethnocentrism. The RAHM was supported, such that increased perceived patient responsibility led to increased provider anger and reduced provider helping intentions, whereas decreased perceived patient responsibility led to increased provider empathy and helping intentions. Additionally, an interaction effect between race and perceived patient responsibility occurred such that bias toward the Black patient was most likely to occur in the control condition. Perceived patient responsibility affects provider helping intentions and interacts with patient race to influence provider perceptions of patient characteristics. Communication on rationales for non-compliance as associated with perceived responsibility may lead to better or worse patient care as providers make attributions about patients based on these factors. © 2013 John Wiley & Sons Ltd.

  1. Assessment of reward responsiveness in the response bias probabilistic reward task in rats: implications for cross-species translational research.

    Science.gov (United States)

    Der-Avakian, A; D'Souza, M S; Pizzagalli, D A; Markou, A

    2013-08-27

    Mood disorders, such as major depressive disorder, are characterized by abnormal reward responsiveness. The Response Bias Probabilistic Reward Task (hereafter referred to as probabilistic reward task (PRT)) quantifies reward responsiveness in human subjects, and an equivalent animal assessment is needed to facilitate preclinical translational research. Thus, the goals of the present studies were to develop, validate and characterize a rat analog of the PRT. Adult male Wistar and Long-Evans rats were trained in operant testing chambers to discriminate between two tone stimuli that varied in duration (0.5 and 2 s). During a subsequent test session consisting of 100 trials, the two tones were made ambiguous (0.9 and 1.6 s) and correct identification of one tone was reinforced with a food pellet three times more frequently than the other tone. In subsequent experiments, Wistar rats were administered either a low dose of the dopamine D2/D3 receptor agonist pramipexole (0.1 mg kg(-1), subcutaneous) or the psychostimulant amphetamine (0.5 mg kg(-1), intraperitoneal) before the test session. Similar to human subjects, both rat strains developed a response bias toward the more frequently reinforced stimulus, reflecting robust reward responsiveness. Mirroring prior findings in humans, a low dose of pramipexole blunted response bias. Moreover, in rats, amphetamine potentiated response bias. These results indicate that in rats, reward responsiveness can be quantified and bidirectionally modulated by pharmacological manipulations that alter striatal dopamine transmission. Thus, this new procedure in rats, which is conceptually and procedurally analogous to the one used in humans, provides a reverse translational platform to investigate abnormal reward responsiveness across species.

  2. Intergroup relationships do not reduce racial bias in empathic neural responses to pain.

    Science.gov (United States)

    Contreras-Huerta, Luis Sebastian; Hielscher, Emily; Sherwell, Chase S; Rens, Natalie; Cunnington, Ross

    2014-11-01

    Perceiving the pain of others activates similar neural structures to those involved in the direct experience of pain, including sensory and affective-motivational areas. Empathic responses can be modulated by race, such that stronger neural activation is elicited by the perception of pain in people of the same race compared with another race. In the present study, we aimed to identify when racial bias occurs in the time course of neural empathic responses to pain. We also investigated whether group affiliation could modulate the race effect. Using the minimal group paradigm, we assigned participants to one of two mixed-race teams. We examined event-related potentials from participants when viewing members of their own and the other team receiving painful or non-painful touch. We identified a significant racial bias in early ERP components at N1 over frontal electrodes, where Painful stimuli elicited a greater negative shift relative to Non-Painful stimuli in response to own race faces only. A long latency empathic response was also found at P3, where there was significant differentiation between Painful and Non-Painful stimuli regardless of Race or Group. There was no evidence that empathy-related brain activity was modulated by minimal group manipulation. These results support a model of empathy for pain that consists of early, automatic bias towards own-race empathic responses and a later top-down cognitive evaluation that does not differentiate between races and may ultimately lead to unbiased behaviour.

  3. Getting physicians to open the survey: little evidence that an envelope teaser increases response rates

    Directory of Open Access Journals (Sweden)

    Ziegenfuss Jeanette Y

    2012-03-01

    Full Text Available Abstract Background Physician surveys are an important tool to assess attitudes, beliefs and self-reported behaviors of this policy relevant group. In order for a physician to respond to a mailed survey, they must first open the envelope. While there is some evidence that package elements can impact physician response rates, the impact of an envelope teaser is unknown. Here we assess this by testing the impact of adding a brightly colored "$25 incentive" sticker to the outside of an envelope on response rates and nonresponse bias in a survey of physicians. Methods In the second mailing of a survey assessing physicians' moral beliefs and views on controversial health care topics, initial nonrespondents were randomly assigned to receive a survey in an envelope with a colored "$25 incentive" sticker (teaser group or an envelope without a sticker (control group. Response rates were compared between the teaser and control groups overall and by age, gender, region of the United States, specialty and years in practice. Nonresponse bias was assessed by comparing the demographic composition of the respondents to the nonrespondents in the experimental and control condition. Results No significant differences in response rates were observed between the experimental and control conditions overall (p = 0.38 or after stratifying by age, gender, region, or practice type. Within the teaser condition, there was some variation in response rate by years since graduation. There was no independent effect of the teaser on response when simultaneously controlling for demographic characteristics (OR = 0.875, p = 0.4112. Conclusions Neither response rates nor nonresponse bias were impacted by the use of an envelope teaser in a survey of physicians in the United States.

  4. Triangles in ROC space: History and theory of "nonparametric" measures of sensitivity and response bias.

    Science.gov (United States)

    Macmillan, N A; Creelman, C D

    1996-06-01

    Can accuracy and response bias in two-stimulus, two-response recognition or detection experiments be measured nonparametrically? Pollack and Norman (1964) answered this question affirmatively for sensitivity, Hodos (1970) for bias: Both proposed measures based on triangular areas in receiver-operating characteristic space. Their papers, and especially a paper by Grier (1971) that provided computing formulas for the measures, continue to be heavily cited in a wide range of content areas. In our sample of articles, most authors described triangle-based measures as making fewer assumptions than measures associated with detection theory. However, we show that statistics based on products or ratios of right triangle areas, including a recently proposed bias index and a not-yetproposed but apparently plausible sensitivity index, are consistent with a decision process based on logistic distributions. Even the Pollack and Norman measure, which is based on non-right triangles, is approximately logistic for low values of sensitivity. Simple geometric models for sensitivity and bias are not nonparametric, even if their implications are not acknowledged in the defining publications.

  5. Characteristics of non-response in the Danish Health Interview Surveys, 1987-1994

    DEFF Research Database (Denmark)

    Kjøller, Mette; Thoning, Henrik

    2005-01-01

    -response biased the estimated population prevalence of morbidity when solely based on responders. METHODS: The data were for the 23,096 adults sampled for the Danish Health Interview Surveys in 1987, 1991 and 1994. All were followed using the National Patient Registry to obtain such information as hospital...... data collection. CONCLUSIONS: Although admission rates differed between respondents and non-respondents these differences were too small to bias the estimated population prevalence of morbidity when solely based on respondents....... admissions. RESULTS: Non-response increased from 20.0% in 1987 to 22.6% in 1994. Four combinations of background variables characterized the non-response: gender and age; gender and civil status; county of residence and age; survey year and age. Non-respondents and respondents had identical gender- and age...

  6. Sensitivity and specificity of a digit symbol recognition trial in the identification of response bias.

    Science.gov (United States)

    Kim, Nancy; Boone, Kyle B; Victor, Tara; Lu, Po; Keatinge, Carolyn; Mitchell, Cary

    2010-08-01

    Recently published practice standards recommend that multiple effort indicators be interspersed throughout neuropsychological evaluations to assess for response bias, which is most efficiently accomplished through use of effort indicators from standard cognitive tests already included in test batteries. The present study examined the utility of a timed recognition trial added to standard administration of the WAIS-III Digit Symbol subtest in a large sample of "real world" noncredible patients (n=82) as compared with credible neuropsychology clinic patients (n=89). Scores from the recognition trial were more sensitive in identifying poor effort than were standard Digit Symbol scores, and use of an equation incorporating Digit Symbol Age-Corrected Scaled Scores plus accuracy and time scores from the recognition trial was associated with nearly 80% sensitivity at 88.7% specificity. Thus, inclusion of a brief recognition trial to Digit Symbol administration has the potential to provide accurate assessment of response bias.

  7. Participation bias in postal surveys among older adults: the role played by self-reported health, physical functional decline and frailty.

    Science.gov (United States)

    Barreto, Philipe de Souto

    2012-01-01

    Postal survey is a simple and efficient way to collect information in large study samples. The purpose of this study was to find out differences between older adults who responded to a postal survey on health outcomes and those who did not, and to examine the importance of frailty, physical functional decline and poor self-reported health in determining non-response. We mailed out a questionnaire on general health twice at a year's interval to 1000 individuals ≥60 years, and members of the medical insurance scheme of the French national education system. At Year1, 535 persons responded to the questionnaire (65% women, 70.9 ± 8.4 years). A year later (Year2), we obtained 384 responses (63.3% women, 70.5 ± 7.8 years). Compared to respondents, non-respondents at Year2 were more frequently categorized as frail, reported more often to be in bad health, and had more physical functional declines. Frailty, physical functional decline and poor self-reported health increased the likelihood of not responding to Year2 questionnaire, with poor self-reported health weakening the association of physical functional decline and non-response. Respondents of this postal survey are fitter and healthier than non-respondents. This participation bias precludes the generalization of postal surveys results.

  8. Polysaccharide Responsiveness Is Not Biased by Prior Pneumococcal-Conjugate Vaccination

    Science.gov (United States)

    Bernth-Jensen, Jens Magnus; Søgaard, Ole Schmeltz

    2013-01-01

    Polysaccharide responsiveness is tested by measuring antibody responses to polysaccharide vaccines to diagnose for humoral immunodeficiency. A common assumption is that this responsiveness is biased by any previous exposure to the polysaccharides in the form of protein-coupled polysaccharide vaccines, such as those used in many childhood vaccination programmes. To examine this assumption, we investigated the effect of protein-coupled polysaccharide vaccination on subsequent polysaccharide responsiveness. HIV-infected adults (n = 47) were vaccinated twice with protein-coupled polysaccharides and six months later with pure polysaccharides. We measured immunoglobulin G responses against three polysaccharides present in only the polysaccharide vaccine (non-memory polysaccharides) and seven recurring polysaccharides (memory polysaccharides). Responsiveness was evaluated according to the consensus guidelines published by the American immunology societies. Impaired responsiveness to non-memory polysaccharides was more frequent than to memory polysaccharides (51% versus 28%, P = 0.015), but the individual polysaccharides did not differ in triggering sufficient responses (74% versus 77%, P = 0.53). Closer analysis revealed important shortcomings of the current evaluation guidelines. The interpreted responseś number and their specificities influenced the likelihood of impaired responsiveness in a complex manor. This influence was propelled by the dichotomous approaches inherent to the American guidelines. We therefore define a novel more robust polysaccharide responsiveness measure, the Z-score, which condenses multiple, uniformly weighted responses into one continuous variable. Using the Z-score, responsiveness to non-memory polysaccharides and memory-polysaccharides were found to correlate (R2 = 0.59, Presponsiveness was not biased by prior protein-coupled polysaccharide vaccination in HIV-infected adults. Studies in additional populations are warranted

  9. Undersampling Bias: The Null Hypothesis for Singleton Species in Tropical Arthropod Surveys

    National Research Council Canada - National Science Library

    Jonathan A. Coddington; Ingi Agnarsson; Jeremy A. Miller; Matjaž Kuntner; Gustavo Hormiga

    2009-01-01

    ...–2 million individuals, implying approximately 4% true singleton frequency. 5. Undersampling causes systematic negative bias of species richness, and should be the default null hypothesis for singleton frequencies. 6...

  10. The VIMOS Public Extragalactic Redshift Survey (VIPERS). Measuring non-linear galaxy bias at z ~ 0.8

    Science.gov (United States)

    Di Porto, C.; Branchini, E.; Bel, J.; Marulli, F.; Bolzonella, M.; Cucciati, O.; de la Torre, S.; Granett, B. R.; Guzzo, L.; Marinoni, C.; Moscardini, L.; Abbas, U.; Adami, C.; Arnouts, S.; Bottini, D.; Cappi, A.; Coupon, J.; Davidzon, I.; De Lucia, G.; Fritz, A.; Franzetti, P.; Fumana, M.; Garilli, B.; Ilbert, O.; Iovino, A.; Krywult, J.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; McCracken, H. J.; Paioro, L.; Polletta, M.; Pollo, A.; Scodeggio, M.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Burden, A.; Marchetti, A.; Martizzi, D.; Mellier, Y.; Nichol, R. C.; Peacock, J. A.; Percival, W. J.; Viel, M.; Wolk, M.; Zamorani, G.

    2016-10-01

    Aims: We use the first release of the VImos Public Extragalactic Redshift Survey of galaxies (VIPERS) of ~50 000 objects to measure the biasing relation between galaxies and mass in the redshift range z = [ 0.5,1.1 ]. Methods: We estimate the 1-point distribution function [PDF] of VIPERS galaxies from counts in cells and, assuming a model for the mass PDF, we infer their mean bias relation. The reconstruction of the bias relation is performed through a novel method that accounts for Poisson noise, redshift distortions, inhomogeneous sky coverage. and other selection effects. With this procedure we constrain galaxy bias and its deviations from linearity down to scales as small as 4 h-1 Mpc and out to z = 1.1. Results: We detect small (up to 2%) but statistically significant (up to 3σ) deviations from linear bias. The mean biasing function is close to linear in regions above the mean density. The mean slope of the biasing relation is a proxy to the linear bias parameter. This slope increases with luminosity, which is in agreement with results of previous analyses. We detect a strong bias evolution only for z> 0.9, which is in agreement with some, but not all, previous studies. We also detect a significant increase of the bias with the scale, from 4 to 8 h-1 Mpc , now seen for the first time out to z = 1. The amplitude of non-linearity depends on redshift, luminosity, and scale, but no clear trend is detected. Owing to the large cosmic volume probed by VIPERS, we find that the mismatch between the previous estimates of bias at z ~ 1 from zCOSMOS and VVDS-Deep galaxy samples is fully accounted for by cosmic variance. Conclusions: The results of our work confirm the importance of going beyond the over-simplistic linear bias hypothesis showing that non-linearities can be accurately measured through the applications of the appropriate statistical tools to existing datasets like VIPERS. Based on observations collected at the European Southern Observatory, Paranal, Chile

  11. Effects of temporally biased watering on the nitrogen response of Chenopodium album

    Science.gov (United States)

    Kinugasa, Toshihiko; Hozumi, Yumi

    2017-07-01

    Plant growth responses to an increasing N deposition are stimulated by an increase in annual precipitation, but such a stimulation has not always been found. We hypothesized that the effect of precipitation on plant N responses can change with temporally biased precipitation: a plant N response will be suppressed when precipitation is lower in the late growing period because larger plants are more susceptible to water limitations. We grew Chenopodium album under a high and low N application level with three watering patterns while maintaining the total supplied watering amount during the experimental period: constant watering, low watering in the first period and high watering in the latter period, and high watering in the first period and low watering in the latter period. The watering pattern did not affect plant dry mass under low N conditions. The plant dry mass under high N conditions was reduced by low watering in the first period, but the reduction was fully compensated in the subsequent high watering period by the stimulation of photosynthesis. Low watering following high watering under high N conditions did not suppress plant growth, but partial leaf wilting was observed at the end of the experimental period. Finally, at the end of the experiment, the response of plant dry mass to N was not different among the watering patterns. We concluded that a plant's response to increasing N deposition could be affected by temporally biased precipitation, depending on the scale of the precipitation bias and the ability of the plant to compensate or mitigate growth inhibition due to a water deficit. Precipitation deficits later in the growing period may be more detrimental to plant growth and can reduce plant responses to an increasing N deposition.

  12. Oxytocin modulates the racial bias in neural responses to others' suffering.

    Science.gov (United States)

    Sheng, Feng; Liu, Yi; Zhou, Bin; Zhou, Wen; Han, Shihui

    2013-02-01

    The intergroup relationship between a perceiver and a target person influences empathic neural responses to others' suffering, which are increased for racial in-group members compared to out-group members. The current study investigated whether oxytocin (OT), a neuropeptide that has been linked to empathic concern and in-group favoritism, contributes to the racial bias in empathic neural responses. Event-related brain potentials were recorded in Chinese male adults during race judgments on Asian and Caucasian faces expressing pain or showing a neutral expression after intranasal self-administration of OT or placebo. A fronto-central positive activity at 128-188 ms (P2) was of larger amplitude in response to the pain expressions compared with the neutral expressions of racial in-group members but not of racial out-group members. OT treatment increased this racial in-group bias in neural responses and resulted in its correlation with a positive implicit attitude toward racial in-group members. Our findings suggest that OT interacts with the intergroup relationship to modulate empathic neural responses to others' suffering.

  13. Six weeks of meditation training influences response bias in a discrimination task with emotional distractors

    Directory of Open Access Journals (Sweden)

    Carolina B Menezes

    2012-06-01

    Full Text Available Introduction: Focused attention meditation is the voluntary focusing of attention on a chosen object in a sustained fashion, whose objective is to develop attentional and emotional regulatory skills./objective: We investigated the effect of a six-week focused attention meditation training on a discrimination task with emotional distractors by comparing participants’ discriminability and bias before and after training. Method: College students were randomly assigned to either focused meditation (N=35, progressive relaxation (N=37, or control groups (N=28. 120 neutral and 120 emotional - negative and arousing – pictures (9º x 12º, flanked by two peripheral bars (0.3º x 0.3º, equidistant from the centre of the picture (9º, were equally and randomly distributed and displayed among three blocks, one with low attentional (LA and two with high attentional demand (HA. Participants indicated if bars were parallel or not by pressing one of two buttons. In LA and HA conditions, respectively, bars differed with 90º and 6º in half of the trials. Trials started with a fixation cross (1500ms followed by the pictures and bars (200ms. Next, a chessboard remained on the screen until a response was given or for 2000ms. Results: Mixed-design ANOVAs showed no discriminability difference across groups (meditation=26; relaxation=24; control=24 pre-post training; only task difficulty affected discriminability [F(1,68 = 739.8, p < .001; LA > HA]. Response bias was affected by difficulty [F(1,68 = 81.2, p < .001; LA < HA], and testing session [F(1,68 = 23.1,  p < .001; pre > post]. Additionally, there was a significant difficulty × session × group interaction [F(2,68 = 4.02,  p = .02]: meditation (M = .58, SE =.36 and relaxation (M = .65, SE =.36 presented a reduction in response bias relative to control (M = .69, SE =.37, but only after training in the HA condition (p < 0.05. Conclusion: The reduction in response bias suggests that meditation and

  14. Bias dependence of the response of superconducting tunnel junctions used as photon detectors

    CERN Document Server

    Poelaert, A; Peacock, A; Kozorezov, A; Wigmore, J K

    2000-01-01

    In the last decade, several research groups have developed superconducting tunnel junctions (STJ) for photon detection in astronomy. Despite extensive studies, the behavior of multi-layered devices, subject to the superconducting proximity effect (proximized devices), has remained difficult to model. Recently, a new model has been presented, leading to a more realistic approach for the photon detection within an STJ. This model is based on the existence of local traps in the superconducting electrodes of the STJ. In this paper, we show that the new model is successful in predicting the bias dependence of the response of an STJ. The bias dependence also demonstrates that the quasiparticles, i.e. the charge carriers created as a result of the photon absorption process, cannot relax down to the superconducting energy gap. This result is important, since most theoretical developments to date (implicitly) assume that quasiparticle relax to the gap energy. crystal-structure; energy-levels; tantalum-; traps cooper-p...

  15. Investigating Assessment Bias for Constructed Response Explanation Tasks: Implications for Evaluating Performance Expectations for Scientific Practice

    Science.gov (United States)

    Federer, Meghan Rector

    Assessment is a key element in the process of science education teaching and research. Understanding sources of performance bias in science assessment is a major challenge for science education reforms. Prior research has documented several limitations of instrument types on the measurement of students' scientific knowledge (Liu et al., 2011; Messick, 1995; Popham, 2010). Furthermore, a large body of work has been devoted to reducing assessment biases that distort inferences about students' science understanding, particularly in multiple-choice [MC] instruments. Despite the above documented biases, much has yet to be determined for constructed response [CR] assessments in biology and their use for evaluating students' conceptual understanding of scientific practices (such as explanation). Understanding differences in science achievement provides important insights into whether science curricula and/or assessments are valid representations of student abilities. Using the integrative framework put forth by the National Research Council (2012), this dissertation aimed to explore whether assessment biases occur for assessment practices intended to measure students' conceptual understanding and proficiency in scientific practices. Using a large corpus of undergraduate biology students' explanations, three studies were conducted to examine whether known biases of MC instruments were also apparent in a CR instrument designed to assess students' explanatory practice and understanding of evolutionary change (ACORNS: Assessment of COntextual Reasoning about Natural Selection). The first study investigated the challenge of interpreting and scoring lexically ambiguous language in CR answers. The incorporation of 'multivalent' terms into scientific discourse practices often results in statements or explanations that are difficult to interpret and can produce faulty inferences about student knowledge. The results of this study indicate that many undergraduate biology majors

  16. The bispectrum of galaxies from high-redshift galaxy surveys: Primordial non-Gaussianity and non-linear galaxy bias

    Energy Technology Data Exchange (ETDEWEB)

    Sefusatti, Emiliano; /Fermilab; Komatsu, Eiichiro; /Texas U., Astron. Dept.

    2007-05-01

    The greatest challenge in the interpretation of galaxy clustering data from any surveys is galaxy bias. Using a simple Fisher matrix analysis, we show that the bispectrum provides an excellent determination of linear and non-linear bias parameters of intermediate and high-z galaxies, when all measurable triangle configurations down to mildly non-linear scales, where perturbation theory is still valid, are included. The bispectrum is also a powerful probe of primordial non-Gaussianity. The planned galaxy surveys at z {approx}> 2 should yield constraints on non-Gaussian parameters, f{sub NL}{sup loc.} and f{sub NL}{sup eq.}, that are comparable to, or even better than, those from CMB experiments. We study how these constraints improve with volume, redshift range, as well as the number density of galaxies. Finally we show that a halo occupation distribution may be used to improve these constraints further by lifting degeneracies between gravity, bias, and primordial non-Gaussianity.

  17. Multigenerational response to artificial selection for biased clutch sex ratios in Tigriopus californicus populations.

    Science.gov (United States)

    Alexander, H J; Richardson, J M L; Anholt, B R

    2014-09-01

    Polygenic sex determination (PSD) is relatively rare and theoretically evolutionary unstable, yet has been reported across a range of taxa. Evidence for multilocus PSD is provided by (i) large between-family variance in sex ratio, (ii) paternal and maternal effects on family sex ratio and (iii) response to selection for family sex ratio. This study tests the polygenic hypothesis of sex determination in the harpacticoid copepod Tigriopus californicus using the criterion of response to selection. We report the first multigenerational quantitative evidence that clutch sex ratio responds to artificial selection in both directions (selection for male- and female-biased families) and in multiple populations of T. californicus. In the five of six lines that showed a response to selection, realized heritability estimated by multigenerational analysis ranged from 0.24 to 0.58. Divergence of clutch sex ratio between selection lines is rapid, with response to selection detectable within the first four generations of selection.

  18. Galaxy bias from the Dark Energy Survey Science Verification data: combining galaxy density maps and weak lensing maps

    Energy Technology Data Exchange (ETDEWEB)

    Chang, C.; Pujol, A.; Gaztañaga, E.; Amara, A.; Réfrégier, A.; Bacon, D.; Becker, M. R.; Bonnett, C.; Carretero, J.; Castander, F. J.; Crocce, M.; Fosalba, P.; Giannantonio, T.; Hartley, W.; Jarvis, M.; Kacprzak, T.; Ross, A. J.; Sheldon, E.; Troxel, M. A.; Vikram, V.; Zuntz, J.; Abbott, T. M. C.; Abdalla, F. B.; Allam, S.; Annis, J.; Benoit-Lévy, A.; Bertin, E.; Brooks, D.; Buckley-Geer, E.; Burke, D. L.; Capozzi, D.; Rosell, A. Carnero; Kind, M. Carrasco; Cunha, C. E.; D' Andrea, C. B.; da Costa, L. N.; Desai, S.; Diehl, H. T.; Dietrich, J. P.; Doel, P.; Eifler, T. F.; Estrada, J.; Evrard, A. E.; Flaugher, B.; Frieman, J.; Goldstein, D. A.; Gruen, D.; Gruendl, R. A.; Gutierrez, G.; Honscheid, K.; Jain, B.; James, D. J.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Li, T. S.; Lima, M.; Marshall, J. L.; Martini, P.; Melchior, P.; Miller, C. J.; Miquel, R.; Mohr, J. J.; Nichol, R. C.; Nord, B.; Ogando, R.; Plazas, A. A.; Reil, K.; Romer, A. K.; Roodman, A.; Rykoff, E. S.; Sanchez, E.; Scarpine, V.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thomas, D.; Walker, A. R.

    2016-04-15

    We measure the redshift evolution of galaxy bias from a magnitude-limited galaxy sample by combining the galaxy density maps and weak lensing shear maps for a $\\sim$116 deg$^{2}$ area of the Dark Energy Survey (DES) Science Verification data. This method was first developed in Amara et al. (2012) and later re-examined in a companion paper (Pujol et al., in prep) with rigorous simulation tests and analytical treatment of tomographic measurements. In this work we apply this method to the DES SV data and measure the galaxy bias for a magnitude-limited galaxy sample. We find the galaxy bias and 1$\\sigma$ error bars in 4 photometric redshift bins to be 1.33$\\pm$0.18 (z=0.2-0.4), 1.19$\\pm$0.23 (z=0.4-0.6), 0.99$\\pm$0.36 ( z=0.6-0.8), and 1.66$\\pm$0.56 (z=0.8-1.0). These measurements are consistent at the 1-2$\\sigma$ level with mea- surements on the same dataset using galaxy clustering and cross-correlation of galaxies with CMB lensing. In addition, our method provides the only $\\sigma_8$-independent constraint among the three. We forward-model the main observational effects using mock galaxy catalogs by including shape noise, photo-z errors and masking effects. We show that our bias measurement from the data is consistent with that expected from simulations. With the forthcoming full DES data set, we expect this method to provide additional constraints on the galaxy bias measurement from more traditional methods. Furthermore, in the process of our measurement, we build up a 3D mass map that allows further exploration of the dark matter distribution and its relation to galaxy evolution.

  19. Galaxy bias from the Dark Energy Survey Science Verification data: combining galaxy density maps and weak lensing maps

    Science.gov (United States)

    Chang, C.; Pujol, A.; Gaztañaga, E.; Amara, A.; Réfrégier, A.; Bacon, D.; Becker, M. R.; Bonnett, C.; Carretero, J.; Castander, F. J.; Crocce, M.; Fosalba, P.; Giannantonio, T.; Hartley, W.; Jarvis, M.; Kacprzak, T.; Ross, A. J.; Sheldon, E.; Troxel, M. A.; Vikram, V.; Zuntz, J.; Abbott, T. M. C.; Abdalla, F. B.; Allam, S.; Annis, J.; Benoit-Lévy, A.; Bertin, E.; Brooks, D.; Buckley-Geer, E.; Burke, D. L.; Capozzi, D.; Rosell, A. Carnero; Kind, M. Carrasco; Cunha, C. E.; D'Andrea, C. B.; da Costa, L. N.; Desai, S.; Diehl, H. T.; Dietrich, J. P.; Doel, P.; Eifler, T. F.; Estrada, J.; Evrard, A. E.; Flaugher, B.; Frieman, J.; Goldstein, D. A.; Gruen, D.; Gruendl, R. A.; Gutierrez, G.; Honscheid, K.; Jain, B.; James, D. J.; Kuehn, K.; Kuropatkin, N.; Lahav, O.; Li, T. S.; Lima, M.; Marshall, J. L.; Martini, P.; Melchior, P.; Miller, C. J.; Miquel, R.; Mohr, J. J.; Nichol, R. C.; Nord, B.; Ogando, R.; Plazas, A. A.; Reil, K.; Romer, A. K.; Roodman, A.; Rykoff, E. S.; Sanchez, E.; Scarpine, V.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Swanson, M. E. C.; Tarle, G.; Thomas, D.; Walker, A. R.

    2016-07-01

    We measure the redshift evolution of galaxy bias for a magnitude-limited galaxy sample by combining the galaxy density maps and weak lensing shear maps for a ˜116 deg2 area of the Dark Energy Survey (DES) Science Verification (SV) data. This method was first developed in Amara et al. and later re-examined in a companion paper with rigorous simulation tests and analytical treatment of tomographic measurements. In this work we apply this method to the DES SV data and measure the galaxy bias for a i < 22.5 galaxy sample. We find the galaxy bias and 1σ error bars in four photometric redshift bins to be 1.12 ± 0.19 (z = 0.2-0.4), 0.97 ± 0.15 (z = 0.4-0.6), 1.38 ± 0.39 (z = 0.6-0.8), and 1.45 ± 0.56 (z = 0.8-1.0). These measurements are consistent at the 2σ level with measurements on the same data set using galaxy clustering and cross-correlation of galaxies with cosmic microwave background lensing, with most of the redshift bins consistent within the 1σ error bars. In addition, our method provides the only σ8 independent constraint among the three. We forward model the main observational effects using mock galaxy catalogues by including shape noise, photo-z errors, and masking effects. We show that our bias measurement from the data is consistent with that expected from simulations. With the forthcoming full DES data set, we expect this method to provide additional constraints on the galaxy bias measurement from more traditional methods. Furthermore, in the process of our measurement, we build up a 3D mass map that allows further exploration of the dark matter distribution and its relation to galaxy evolution.

  20. Innocent until Primed: Mock Jurors' Racially Biased Response to the Presumption of Innocence

    Science.gov (United States)

    Young, Danielle M.; Levinson, Justin D.; Sinnett, Scott

    2014-01-01

    Background Research has shown that crime concepts can activate attentional bias to Black faces. This study investigates the possibility that some legal concepts hold similar implicit racial cues. Presumption of innocence instructions, a core legal principle specifically designed to eliminate bias, may instead serve as an implicit racial cue resulting in attentional bias. Methodology/Principal findings The experiment was conducted in a courtroom with participants seated in the jury box. Participants first watched a video of a federal judge reading jury instructions that contained presumption of innocence instructions, or matched length alternative instructions. Immediately following this video a dot-probe task was administered to assess the priming effect of the jury instructions. Presumption of innocence instructions, but not the alternative instructions, led to significantly faster response times to Black faces when compared with White faces. Conclusions/Significance These findings suggest that the core principle designed to ensure fairness in the legal system actually primes attention for Black faces, indicating that this supposedly fundamental protection could trigger racial stereotypes. PMID:24643050

  1. Innocent until primed: mock jurors' racially biased response to the presumption of innocence.

    Directory of Open Access Journals (Sweden)

    Danielle M Young

    Full Text Available BACKGROUND: Research has shown that crime concepts can activate attentional bias to Black faces. This study investigates the possibility that some legal concepts hold similar implicit racial cues. Presumption of innocence instructions, a core legal principle specifically designed to eliminate bias, may instead serve as an implicit racial cue resulting in attentional bias. METHODOLOGY/PRINCIPAL FINDINGS: The experiment was conducted in a courtroom with participants seated in the jury box. Participants first watched a video of a federal judge reading jury instructions that contained presumption of innocence instructions, or matched length alternative instructions. Immediately following this video a dot-probe task was administered to assess the priming effect of the jury instructions. Presumption of innocence instructions, but not the alternative instructions, led to significantly faster response times to Black faces when compared with White faces. CONCLUSIONS/SIGNIFICANCE: These findings suggest that the core principle designed to ensure fairness in the legal system actually primes attention for Black faces, indicating that this supposedly fundamental protection could trigger racial stereotypes.

  2. Response Bias and the Personality Inventory for DSM-5: Contrasting Self- and Informant-Report.

    Science.gov (United States)

    Quilty, Lena C; Cosentino, Nicole; Bagby, R Michael

    2017-04-03

    Previous research has raised concerns that scores derived from the Personality Inventory for DSM-5 (PID-5; American Psychiatric Association, 2013; Krueger, Derringer, Markon, Watson, & Skodol, 2012) may be compromised by response styles such as underreporting or overreporting. The informant-report form of the PID-5 (PID-5-IRF; Markon, Quilty, Bagby, & Krueger, 2013) has been recommended for use when response bias is an assessment concern. The purpose of the current investigation was to evaluate PID-5 and PID-5-IRF scale score elevations across participants exhibiting signs of overreporting or underreporting. A total of 245 adults completed the PID-5 and the Revised NEO Personality Inventory (NEO PI-R; Costa & McCrae, 1992). A family member or friend of at least 1 year's acquaintance completed the PID-5-IRF for 216 of these. A total of 211 target-informant pairs were available for analysis. Participants were categorized as overreporting and underreporting according to NEO PI-R validity scale cutoffs. The majority of PID-5 scale scores were elevated in those identified as overreporting; more than half of the PID-5-IRF scale scores were similarly elevated. The majority of PID-5 scale scores were lower in those scoring above underreporting cut-offs; however, PID-5-IRF scales were not as consistently or strongly impacted. PID-5 scales were strongly impacted by response bias, whereas PID-5-IRF scores were less strongly impacted overall, and more so by overreporting bias. Caution when using these instruments in the assessment of personality disorders prone to over- or underreporting may be warranted. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  3. Racial bias in neural response to others' pain is reduced with other-race contact.

    Science.gov (United States)

    Cao, Yuan; Contreras-Huerta, Luis Sebastian; McFadyen, Jessica; Cunnington, Ross

    2015-09-01

    Observing the pain of others has been shown to elicit greater activation in sensory and emotional areas of the brain suggested to represent a neural marker of empathy. This modulation of brain responses to others' pain is dependent on the race of the observed person, such that observing own-race people in pain is associated with greater activity in the anterior cingulate and bilateral insula cortices compared to other-race people. Importantly, it is not known how this racial bias to pain in other-race individuals might change over time in new immigrants or might depend on the level and quality of contact with people of the other-race. We investigated these issues by recruiting Chinese students who had first arrived in Australia within the past 6 months to 5 years and assessing their level of contact with other races across different social contexts using comprehensive rating scales. During fMRI, participants observed videos of own-race/other-race individuals, as well as own-group/other-group individuals, receiving painful or non-painful touch. The typical racial bias in neural responses to observed pain was evident, whereby activation in the anterior cingulate cortex (ACC) was greater for pain in own-race compared to other-race people. Crucially, activation in the anterior cingulate to pain in other races increased significantly with the level of contact participants reported with people of the other race. Importantly, this correlation did not depend on the closeness of contact or personal relationships, but simply on the overall level of experience with people of the other race in their every-day environment. Racial bias in neural responses to others' pain, as a neural marker of empathy, therefore changes with experience in new immigrants at least within 5 years of arrival in the new society and, crucially, depends on the level of contact with people of the other race in every-day life contexts.

  4. Mortality salience enhances racial in-group bias in empathic neural responses to others' suffering.

    Science.gov (United States)

    Li, Xiaoyang; Liu, Yi; Luo, Siyang; Wu, Bing; Wu, Xinhuai; Han, Shihui

    2015-09-01

    Behavioral research suggests that mortality salience (MS) leads to increased in-group identification and in-group favoritism in prosocial behavior. What remains unknown is whether and how MS influences brain activity that mediates emotional resonance with in-group and out-group members and is associated with in-group favoritism in helping behavior. The current work investigated MS effects on empathic neural responses to racial in-group and out-group members' suffering. Experiments 1 and 2 respectively recorded event related potentials (ERPs) and blood oxygen level dependent signals to pain/neutral expressions of Asian and Caucasian faces from Chinese adults who had been primed with MS or negative affect (NA). Experiment 1 found that an early frontal/central activity (P2) was more strongly modulated by pain vs. neutral expressions of Asian than Caucasian faces, but this effect was not affected by MS vs. NA priming. However, MS relative to NA priming enhanced racial in-group bias in long-latency neural response to pain expressions over the central/parietal regions (P3). Experiment 2 found that MS vs. NA priming increased racial in-group bias in empathic neural responses to pain expression in the anterior and mid-cingulate cortex. Our findings indicate that reminding mortality enhances brain activity that differentiates between racial in-group and out-group members' emotional states and suggest a neural basis of in-group favoritism under mortality threat.

  5. Task modulations of racial bias in neural responses to others' suffering.

    Science.gov (United States)

    Sheng, Feng; Liu, Qiang; Li, Hong; Fang, Fang; Han, Shihui

    2014-03-01

    Recent event related brain potential research observed a greater frontal activity to pain expressions of racial in-group than out-group members and such racial bias in neural responses to others' suffering was modulated by task demands that emphasize race identity or painful feeling. However, as pain expressions activate multiple brain regions in the pain matrix, it remains unclear which part of the neural circuit in response to others' suffering undergoes modulations by task demands. We scanned Chinese adults, using functional MRI, while they categorized Asian and Caucasian faces with pain or neutral expressions in terms of race or identified painful feelings of each individual face. We found that pain vs. neutral expressions of Asian but not Caucasian faces activated the anterior cingulate (ACC) and anterior insular (AI) activity during race judgments. However, pain compared to race judgments increased ACC and AI activity to pain expressions of Caucasian but not Asian faces. Moreover, race judgments induced increased activity in the dorsal medial prefrontal cortex whereas pain judgments increased activity in the bilateral temporoparietal junction. The results suggest that task demands emphasizing an individual's painful feeling increase ACC/AI activities to pain expressions of racial out-group members and reduce the racial bias in empathic neural responses.

  6. Use of the WAIS-III picture completion subtest as an embedded measure of response bias.

    Science.gov (United States)

    Solomon, Ryan E; Boone, Kyle Brauer; Miora, Deborah; Skidmore, Sherry; Cottingham, Maria; Victor, Tara; Ziegler, Elizabeth; Zeller, Michelle

    2010-10-01

    In the present study a large sample of credible patients (n = 172) scored significantly higher than a large sample of noncredible participants (n = 195) on several WAIS-III Picture Completion variables: Age Adjusted Scaled Score, raw score, a "Rarely Missed" index (the nine items least often missed by credible participants), a "Rarely Correct" index (nine items correct WAIS-III is an effective measure of response bias, and that it may have a unique role in identifying suboptimal effort in less-educated test takers.

  7. Estimation of bias errors in measured airplane responses using maximum likelihood method

    Science.gov (United States)

    Klein, Vladiaslav; Morgan, Dan R.

    1987-01-01

    A maximum likelihood method is used for estimation of unknown bias errors in measured airplane responses. The mathematical model of an airplane is represented by six-degrees-of-freedom kinematic equations. In these equations the input variables are replaced by their measured values which are assumed to be without random errors. The resulting algorithm is verified with a simulation and flight test data. The maximum likelihood estimates from in-flight measured data are compared with those obtained by using a nonlinear-fixed-interval-smoother and an extended Kalmar filter.

  8. Beyond self-serving bias: diffusion of responsibility reduces sense of agency and outcome monitoring.

    Science.gov (United States)

    Beyer, Frederike; Sidarus, Nura; Bonicalzi, Sofia; Haggard, Patrick

    2016-11-01

    Diffusion of responsibility across agents has been proposed to underlie decreased helping and increased aggression in group behaviour. However, few studies have directly investigated effects of the presence of other people on how we experience the consequences of our actions. This EEG study investigated whether diffusion of responsibility simply reflects a post-hoc self-serving bias, or rather has direct effects on how we process the outcomes of our actions, and our experience of agency over them. Participants made voluntary actions whose outcomes were more or less negative. Presence of another potential agent reduced participants' sense of agency over those outcomes, even though it was always obvious who caused each outcome. Further, presence of another agent reduced the amplitude of feedback-related negativity evoked by outcome stimuli, suggesting reduced outcome monitoring. The presence of other agents may lead to diffusion of responsibility by weakening the neural linkage between one's actions and their outcomes.

  9. Survey Response Rates and Survey Administration in Counseling and Clinical Psychology: A Meta-Analysis

    Science.gov (United States)

    Van Horn, Pamela S.; Green, Kathy E.; Martinussen, Monica

    2009-01-01

    This article reports results of a meta-analysis of survey response rates in published research in counseling and clinical psychology over a 20-year span and describes reported survey administration procedures in those fields. Results of 308 survey administrations showed a weighted average response rate of 49.6%. Among possible moderators, response…

  10. Survey Response Rates and Survey Administration in Counseling and Clinical Psychology: A Meta-Analysis

    Science.gov (United States)

    Van Horn, Pamela S.; Green, Kathy E.; Martinussen, Monica

    2009-01-01

    This article reports results of a meta-analysis of survey response rates in published research in counseling and clinical psychology over a 20-year span and describes reported survey administration procedures in those fields. Results of 308 survey administrations showed a weighted average response rate of 49.6%. Among possible moderators, response…

  11. The left inferior frontal gyrus is involved in adjusting response bias during a perceptual decision-making task.

    Science.gov (United States)

    Reckless, Greg E; Ousdal, Olga T; Server, Andres; Walter, Henrik; Andreassen, Ole A; Jensen, Jimmy

    2014-05-01

    Changing the way we make decisions from one environment to another allows us to maintain optimal decision-making. One way decision-making may change is how biased one is toward one option or another. Identifying the regions of the brain that underlie the change in bias will allow for a better understanding of flexible decision-making. An event-related, perceptual decision-making task where participants had to detect a picture of an animal amongst distractors was used during functional magnetic resonance imaging. Positive and negative financial motivation were used to affect a change in response bias, and changes in decision-making behavior were quantified using signal detection theory. Response bias became relatively more liberal during both positive and negative motivated trials compared to neutral trials. For both motivational conditions, the larger the liberal shift in bias, the greater the left inferior frontal gyrus (IFG) activity. There was no relationship between individuals' belief that they used a different strategy and their actual change in response bias. The present findings suggest that the left IFG plays a role in adjusting response bias across different decision environments. This suggests a potential role for the left IFG in flexible decision-making.

  12. The bias of galaxies and the density of the universe from the 2dF galaxy redshift survey

    OpenAIRE

    Verde, Licia; Heavens, Alan F.; Percival, Will J.; Matarrese, Sabino

    2002-01-01

    By studying the bispectrum of the galaxy distribution in the 2dF galaxy redhsift survey (2dFGRS), we have shown that 2dFGRS galaxies are unbiased tracers of the mass distribution. This allows us the break the degeneracy intrinsic to power spectrum studies, between the matter density parameter Omega_m and the bias parameter b, and to obtain an accurate measurement of Omega_m: Omega_{m,z_{eff}}=0.27 \\pm 0.06, a measurement obtained from the 2dFGRS alone, independently from other data sets. This...

  13. The Accumulative Effect of Concentric-Biased and Eccentric-Biased Exercise on Cardiorespiratory and Metabolic Responses to Subsequent Low-Intensity Exercise: A Preliminary Study.

    Science.gov (United States)

    Gavin, James Peter; Myers, Stephen; Willems, Mark Elisabeth Theodorus

    2015-12-22

    The study investigated the accumulative effect of concentric-biased and eccentric-biased exercise on cardiorespiratory, metabolic and neuromuscular responses to low-intensity exercise performed hours later. Fourteen young men cycled at low-intensity (~60 rpm at 50% maximal oxygen uptake) for 10 min before, and 12 h after: concentric-biased, single-leg cycling exercise (CON) (performed ~19:30 h) and eccentric-biased, double-leg knee extension exercise (ECC) (~06:30 h the following morning). Respiratory measures were sampled breath-by-breath, with oxidation values derived from stoichiometry equations. Knee extensor neuromuscular function was assessed before and after CON and ECC. Cardiorespiratory responses during low-intensity cycling were unchanged by accumulative CON and ECC. The RER was lower during low-intensity exercise 12 h after CON and ECC (0.88 ± 0.08), when compared to baseline (0.92 ± 0.09; p = 0.02). Fat oxidation increased from baseline (0.24 ± 0.2 g·min(-1)) to 12 h after CON and ECC (0.39 ± 0.2 g·min(-1); p = 0.01). Carbohydrate oxidation decreased from baseline (1.59 ± 0.4 g·min(-1)) to 12 h after CON and ECC (1.36 ± 0.4 g·min(-1); p = 0.03). These were accompanied by knee extensor force loss (right leg: -11.6%, p eccentric-biased exercise led to increased fat oxidation and decreased carbohydrate oxidation, without impairing cardiorespiration, during low-intensity cycling. An accumulation of fatiguing and damaging exercise increases fat utilisation during low intensity exercise performed as little as 12 h later.

  14. The Accumulative Effect of Concentric-Biased and Eccentric-Biased Exercise on Cardiorespiratory and Metabolic Responses to Subsequent Low-Intensity Exercise: A Preliminary Study

    Science.gov (United States)

    Gavin, James Peter; Myers, Stephen; Willems, Mark Elisabeth Theodorus

    2015-01-01

    The study investigated the accumulative effect of concentric-biased and eccentric-biased exercise on cardiorespiratory, metabolic and neuromuscular responses to low-intensity exercise performed hours later. Fourteen young men cycled at low-intensity (~60 rpm at 50% maximal oxygen uptake) for 10 min before, and 12 h after: concentric-biased, single-leg cycling exercise (CON) (performed ~19:30 h) and eccentric-biased, double-leg knee extension exercise (ECC) (~06:30 h the following morning). Respiratory measures were sampled breath-by-breath, with oxidation values derived from stoichiometry equations. Knee extensor neuromuscular function was assessed before and after CON and ECC. Cardiorespiratory responses during low-intensity cycling were unchanged by accumulative CON and ECC. The RER was lower during low-intensity exercise 12 h after CON and ECC (0.88 ± 0.08), when compared to baseline (0.92 ± 0.09; p = 0.02). Fat oxidation increased from baseline (0.24 ± 0.2 g·min−1) to 12 h after CON and ECC (0.39 ± 0.2 g·min−1; p = 0.01). Carbohydrate oxidation decreased from baseline (1.59 ± 0.4 g·min−1) to 12 h after CON and ECC (1.36 ± 0.4 g·min−1; p = 0.03). These were accompanied by knee extensor force loss (right leg: −11.6%, p eccentric-biased exercise led to increased fat oxidation and decreased carbohydrate oxidation, without impairing cardiorespiration, during low-intensity cycling. An accumulation of fatiguing and damaging exercise increases fat utilisation during low intensity exercise performed as little as 12 h later. PMID:26839613

  15. Ganoderma lucidum polysaccharides encapsulated in liposome as an adjuvant to promote Th1-bias immune response.

    Science.gov (United States)

    Liu, Zhenguang; Xing, Jie; Zheng, Sisi; Bo, Ruonan; Luo, Li; Huang, Yee; Niu, Yale; Li, Zhihua; Wang, Deyun; Hu, Yuanliang; Liu, Jiaguo; Wu, Yi

    2016-05-20

    Liposome-based vaccine delivery systems are known to enhance immune responses. Ganoderma lucidum polysaccharides (GLP) have been widely studied as immunomodulator and it could be as inducers of strong immune responses. In the research, GLP and ovalbumin (OVA) were encapsulated into liposome as vaccine and inoculated to mice. The magnitude and kinetics of the humoral and cellular immune responses were investigated. The results showed that GLP-OVA-loaded liposomes (GLPL/OVA) could induce more powerful antigen-specific immune responses than each single-component formulation. Mice immunized with GLPL/OVA displayed higher antigen-specific IgG antibodies, better splenocytes proliferation, higher cytokine secretion by splenocytes and significant activation of CD3+CD4+ and CD3+CD8+ T cells. Thus the GLPL/OVA formulation produced a heightened humoral and cellular immune response, with an overall Th1 bias. Enhanced immune responses elicited by the GLPL/OVA formulation might be attributed to effective activation and mature of DC in draining lymph nodes. Overall, these findings indicate that GLPL have the potential to enhance immune responses as vaccine delivery systems.

  16. The Sloan Digital Sky Survey Reverberation Mapping Project: Biases in z>1.46 Redshifts due to Quasar Diversity

    CERN Document Server

    Denney, K D; Brandt, W N; Grier, C J; Ho, Luis C; Peterson, B M; Trump, J R; Ge, J

    2016-01-01

    We use the coadded spectra of 32 epochs of Sloan Digital Sky Survey (SDSS) Reverberation Mapping Project observations of 482 quasars with z>1.46 to highlight systematic biases in the SDSS- and BOSS-pipeline redshifts due to the natural diversity of quasar properties. We investigate the characteristics of this bias by comparing the BOSS-pipeline redshifts to an estimate from the centroid of HeII 1640. HeII has a low equivalent width but is often well-defined in high-S/N spectra, does not suffer from self-absorption, and has a narrow component that, when present (the case for about half of our sources), produces a redshift estimate that, on average, is consistent with that determined from [OII] to within 1-sigma of the quadrature sum of the HeII and [OII] centroid measurement uncertainties. The large redshift differences of ~1000 km/s, on average, between the BOSS-pipeline and HeII-centroid redshifts suggest there are significant biases in a portion of BOSS quasar redshift measurements. Adopting the HeII-based ...

  17. Social desirability response bias and self-report of psychological distress in pediatric chronic pain patients.

    Science.gov (United States)

    Logan, Deirdre E; Claar, Robyn Lewis; Scharff, Lisa

    2008-06-01

    The objective of this study was to investigate associations between social desirability response bias and self-report of pain, disability, and psychological distress (depression, anxiety, and somatic symptoms) in a sample of children presenting to a multidisciplinary pediatric chronic pain clinic. A retrospective review was conducted on 414 consecutive clinic patients, ages 12-17 years, with chronic pain complaints of at least 3 months' duration. As part of a clinical battery, children completed self-report psychological questionnaires including the Children's Depression Inventory, Children's Somatization Inventory, and Revised Children's Manifest Anxiety Scale including the Lie Scale, an indicator of social desirability influence. Children also provided self report of pain intensity, pain duration and functional disability. Clinician ratings of anxiety and depressive symptoms also were collected. Results show that children scoring high on the measure of social desirability reported fewer symptoms of depression and anxiety compared to children scoring low on the social desirability index. No differences arose between these groups on reports of somatic symptoms, pain duration, or pain-related disability. These findings suggest that social desirability response bias may have implications for the self-report of psychological distress among pediatric chronic pain patients. The limits of self-report of symptoms should be considered in the clinical and research contexts.

  18. Peculiar velocities into the next generation: cosmological parameters from large surveys without bias from non-linear structure

    Science.gov (United States)

    Abate, Alexandra; Bridle, Sarah; Teodoro, Luis F. A.; Warren, Michael S.; Hendry, Martin

    2008-10-01

    We investigate methods to best estimate the normalization of the mass density fluctuation power spectrum (σ8) using peculiar velocity data from a survey like the six-degree Field Galaxy Velocity Survey (6dFGSv). We focus on two potential problems: (i) biases from non-linear growth of structure and (ii) the large number of velocities in the survey. Simulations of ΛCDM-like models are used to test the methods. We calculate the likelihood from a full covariance matrix of velocities averaged in grid cells. This simultaneously reduces the number of data points and smoothes out non-linearities which tend to dominate on small scales. We show how the averaging can be taken into account in the predictions in a practical way, and show the effect of the choice of cell size. We find that a cell size can be chosen that significantly reduces the non-linearities without significantly increasing the error bars on cosmological parameters. We compare our results with those from a principal components analysis following Watkins et al. and Feldman et al. to select a set of optimal moments constructed from linear combinations of the peculiar velocities that are least sensitive to the non-linear scales. We conclude that averaging in grid cells performs equally well. We find that for a survey such as 6dFGSv we can estimate σ8 with less than 3 per cent bias from non-linearities. The expected error on σ8 after marginalizing over Ωm is approximately 16 per cent.

  19. Biasing the development of response topography with nonspecific positive and negative evocative verbal stimuli.

    Science.gov (United States)

    Cody, W J; Grant, D A

    1978-03-01

    Conditioned response (CR) rate and development of CR latency, rise time, and airpuff attenuation were examined for V- and C-form responders using two nonspecific command words, do and don't, as conditioned stimuli (CSs) in single-cue, double-cue, and differential eyelid conditioning. In both single-cue and differential conditioning, regardless of the command word used to signal the unconditioned stimulus (UCS), the Vs produced a higher response rate and learned a better UCS-attenuating response topography than the Cs. However, in a double-cue conditioning paradigm in which both command words were presented alone on different trials and reinforced, response latency was longer and puff attenuation poorer among Vs than when the UCS was signaled by a unique cue. In contrast, adding a second reinforced cue actually enhanced the development of puff-avoidant CR topographies among Cs compared to single-cue conditioning. These results and others indicate that response topography development is to some extent a labile process that can be biased toward either good or poor puff-avoidant properties and that the factors responsible for influencing CR topography differ for Vs and Cs.

  20. The Sloan Digital Sky Survey Reverberation Mapping Project: Biases in z > 1.46 Redshifts Due to Quasar Diversity

    Science.gov (United States)

    Denney, K. D.; Horne, Keith; Brandt, W. N.; Grier, C. J.; Ho, Luis C.; Peterson, B. M.; Trump, J. R.; Ge, J.

    2016-12-01

    We use the coadded spectra of 32 epochs of Sloan Digital Sky Survey (SDSS) Reverberation Mapping Project observations of 482 quasars with z > 1.46 to highlight systematic biases in the SDSS- and Baryon Oscillation Spectroscopic Survey (BOSS)-pipeline redshifts due to the natural diversity of quasar properties. We investigate the characteristics of this bias by comparing the BOSS-pipeline redshifts to an estimate from the centroid of He ii λ1640. He ii has a low equivalent width but is often well-defined in high-S/N spectra, does not suffer from self-absorption, and has a narrow component which, when present (the case for about half of our sources), produces a redshift estimate that, on average, is consistent with that determined from [O ii] to within the He ii and [O ii] centroid measurement uncertainties. The large redshift differences of ˜1000 km s-1, on average, between the BOSS-pipeline and He ii-centroid redshifts, suggest there are significant biases in a portion of BOSS quasar redshift measurements. Adopting the He ii-based redshifts shows that C iv does not exhibit a ubiquitous blueshift for all quasars, given the precision probed by our measurements. Instead, we find a distribution of C iv-centroid blueshifts across our sample, with a dynamic range that (i) is wider than that previously reported for this line, and (ii) spans C iv centroids from those consistent with the systemic redshift to those with significant blueshifts of thousands of kilometers per second. These results have significant implications for measurement and use of high-redshift quasar properties and redshifts, and studies based thereon.

  1. Emotional processing in Parkinson’s disease and schizophrenia: Evidence for response bias deficits in PD

    Directory of Open Access Journals (Sweden)

    Ilona Paulina Laskowska

    2015-09-01

    Full Text Available Deficits in facial emotion recognition in Parkinson’s disease patients has been well documented. Nevertheless, it is still not clear whether facial emotion recognition deficits are secondary to other cognitive impairments. The aim of this study was to answer the question of whether deficits in facial emotion recognition in PD result from impaired sensory processes, or from impaired decision processes. To address this question, we tested the ability to recognize a mixture of basic and complex emotions in 38 non-demented PD patients and 38 healthy controls matched on demographic characteristics. By using a task with an increased level of ambiguity, in conjunction with the Signal Detection Theory, we were able to differentiate between sensitivity and response bias in facial emotion recognition. Sensitivity and response bias for facial emotion recognition were calculated using a d-prime value and a c index respectively. Our study is the first to employ the EIS-F scale for assessing facial emotion recognition among PD patients; to test its validity as an assessment tool, a group comprising schizophrenia patients and healthy controls were also tested. Patients with PD recognized emotions with less accuracy than healthy individuals (d-prime and used a more liberal response criterion (c index. By contrast, patients with schizophrenia merely showed diminished sensitivity (d-prime. Our results suggest that an impaired ability to recognize facial emotions in PD patients may result from both decreased sensitivity and a significantly more liberal response criteria, whereas facial emotion recognition in schizophrenia may stem from a generalized sensory impairment only.

  2. Emotional processing in Parkinson's disease and schizophrenia: evidence for response bias deficits in PD.

    Science.gov (United States)

    Laskowska, Ilona P; Gawryś, Ludwika; Łęski, Szymon; Koziorowski, Dariusz

    2015-01-01

    Deficits in facial emotion recognition in Parkinson's disease (PD) patients has been well documented. Nevertheless, it is still not clear whether facial emotion recognition deficits are secondary to other cognitive impairments. The aim of this study was to answer the question of whether deficits in facial emotion recognition in PD result from impaired sensory processes, or from impaired decision processes. To address this question, we tested the ability to recognize a mixture of basic and complex emotions in 38 non-demented PD patients and 38 healthy controls matched on demographic characteristics. By using a task with an increased level of ambiguity, in conjunction with the signal detection theory, we were able to differentiate between sensitivity and response bias in facial emotion recognition. Sensitivity and response bias for facial emotion recognition were calculated using a d-prime value and a c index respectively. Our study is the first to employ the EIS-F scale for assessing facial emotion recognition among PD patients; to test its validity as an assessment tool, a group comprising schizophrenia patients and healthy controls were also tested. Patients with PD recognized emotions with less accuracy than healthy individuals (d-prime) and used a more liberal response criterion (c index). By contrast, patients with schizophrenia merely showed diminished sensitivity (d-prime). Our results suggest that an impaired ability to recognize facial emotions in PD patients may result from both decreased sensitivity and a significantly more liberal response criteria, whereas facial emotion recognition in schizophrenia may stem from a generalized sensory impairment only.

  3. Spectroscopic observation of SN 2017pp by NUTS (NOT Un-biased Transient Survey)

    Science.gov (United States)

    Pastorello, A.; Elias-Rosa, N.; Benetti, S.; Cappellaro, E.; Terreran, G.; Tomasella, L.; Tronsgaard, R.

    2017-01-01

    The Nordic Optical Telescope (NOT) Unbiased Transient Survey (NUTS; ATel #8992) reports the spectroscopic classification of SN 2017pp in PGC 1378162. The candidate was discovered by F. Ciabattari, E. Mazzoni, S. Donati (ISSP; http://italiansupernovae.org).

  4. The Accumulative Effect of Concentric‐Biased and Eccentric‐ Biased Exercise on Cardiorespiratory and Metabolic Responses to Subsequent Low‐Intensity Exercise: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Gavin James Peter

    2015-12-01

    Full Text Available The study investigated the accumulative effect of concentric-biased and eccentric-biased exercise on cardiorespiratory, metabolic and neuromuscular responses to low-intensity exercise performed hours later. Fourteen young men cycled at low-intensity (~60 rpm at 50% maximal oxygen uptake for 10 min before, and 12 h after: concentric-biased, single-leg cycling exercise (CON (performed ~19:30 h and eccentric-biased, double-leg knee extension exercise (ECC (~06:30 h the following morning. Respiratory measures were sampled breath-by-breath, with oxidation values derived from stoichiometry equations. Knee extensor neuromuscular function was assessed before and after CON and ECC. Cardiorespiratory responses during low-intensity cycling were unchanged by accumulative CON and ECC. The RER was lower during low-intensity exercise 12 h after CON and ECC (0.88 ± 0.08, when compared to baseline (0.92 ± 0.09; p = 0.02. Fat oxidation increased from baseline (0.24 ± 0.2 g·min1 to 12 h after CON and ECC (0.39 ± 0.2 g·min1; p = 0.01. Carbohydrate oxidation decreased from baseline (1.59 ± 0.4 g·min-1 to 12 h after CON and ECC (1.36 ± 0.4 g·min1; p = 0.03. These were accompanied by knee extensor force loss (right leg: -11.6%, p < 0.001; left leg: -10.6%, p = 0.02 and muscle soreness (right leg: 2.5 ± 0.9, p < 0.0001; left leg: 2.3 ± 1.2, p < 0.01. Subsequent concentric-biased and eccentric-biased exercise led to increased fat oxidation and decreased carbohydrate oxidation, without impairing cardiorespiration, during low-intensity cycling. An accumulation of fatiguing and damaging exercise increases fat utilisation during low intensity exercise performed as little as 12 h later.

  5. Increasing Response Rates to Web-Based Surveys

    Science.gov (United States)

    Monroe, Martha C.; Adams, Damian C.

    2012-01-01

    We review a popular method for collecing data--Web-based surveys. Although Web surveys are popular, one major concern is their typically low response rates. Using the Dillman et al. (2009) approach, we designed, pre-tested, and implemented a survey on climate change with Extension professionals in the Southeast. The Dillman approach worked well,…

  6. Uncertainty in the visibility mask of a survey and its effects on the clustering of biased tracers

    Science.gov (United States)

    Colavincenzo, M.; Monaco, P.; Sefusatti, E.; Borgani, S.

    2017-03-01

    The forecasted accuracy of upcoming surveys of large-scale structure cannot be achieved without a proper quantification of the error induced by foreground removal (or other systematics like 0-point photometry offset). Because these errors are highly correlated on the sky, their influence is expected to be especially important at very large scales, at and beyond the first Baryonic Acoustic Oscillation (BAO). In this work we quantify how the uncertainty in the visibility mask of a survey, that gives the survey depth in a specific sky area, influences the measured power spectrum of a sample of tracers of the density field and its covariance matrix. We start from a very large set of 10,000 catalogs of dark matter (DM) halos in periodic cosmological boxes, produced with the PINOCCHIO approximate method. To make an analytic approach feasible, we assume luminosity-independent halo bias and an idealized geometry for the visibility mask, that is constant in square tiles of physical length l; this should be interpreted as the projection, at the observation redshift, of the angular correlation scale of the foreground residuals. We find that the power spectrum of these biased tracers can be expressed as the sum of a cosmological term, a mask term and a term involving their convolution. The mask and convolution terms scale like P propto l2σA2, where σA2 is the variance of the uncertainty on the visibility mask. With l = 30‑100 Mpc/h and σA = 5‑20%, the mask term can be significant at k ~ 0.01‑0.1 h/Mpc, and the convolution term can amount to ~ 1‑10% of the total. The influence of mask uncertainty on power spectrum covariance is more complicated: the coupling of the convolution term with the other two gives rise to several mixed terms, that we quantify by difference using the mock catalogs. These are found to be of the same order of the mask covariance, and to introduce non-diagonal terms at large scales. As a consequence, the power spectrum covariance matrix cannot

  7. Striatal intrinsic reinforcement signals during recognition memory: relationship to response bias and dysregulation in schizophrenia

    Directory of Open Access Journals (Sweden)

    Daniel H Wolf

    2011-12-01

    Full Text Available Ventral striatum (VS is a critical brain region for reinforcement learning and motivation, and VS hypofunction is implicated in psychiatric disorders including schizophrenia. Providing rewards or performance feedback has been shown to activate VS. Intrinisically motivated subjects performing challenging cognitive tasks are likely to engage reinforcement circuitry even in the absence of external feedback or incentives. However, such intrinsic reinforcement responses have received little attention, have not been examined in relation to behavioral performance, and have not been evaluated for impairment in neuropsychiatric disorders such as schizophrenia. Here we used fMRI to examine a challenging 'old' vs. 'new' visual recognition task in healthy subjects and patients with schizophrenia. Targets were unique fractal stimuli previously presented as salient distractors in a visual oddball task, producing incidental memory encoding. Based on the prediction error theory of reinforcement learning, we hypothesized that correct target recognition would activate VS in controls, and that this activation would be greater in subjects with lower expectation of responding correctly as indexed by a more conservative response bias. We also predicted these effects would be reduced in patients with schizophrenia. Consistent with these predictions, controls activated VS and other reinforcement processing regions during correct recognition, with greater VS activation in those with a more conservative response bias. Patients did not show either effect, with significant group differences suggesting hyporesponsivity in patients to internally-generated feedback. These findings highlight the importance of accounting for intrinsic motivation and reward when studying cognitive tasks, and add to growing evidence of reward circuit dysfunction in schizophrenia that may impact cognition and function.

  8. Striatal intrinsic reinforcement signals during recognition memory: relationship to response bias and dysregulation in schizophrenia.

    Science.gov (United States)

    Wolf, Daniel H; Gerraty, Raphaelt; Satterthwaite, Theodore D; Loughead, James; Campellone, Timothy; Elliott, Mark A; Turetsky, Bruce I; Gur, Ruben C; Gur, Raquel E

    2011-01-01

    Ventral striatum (VS) is a critical brain region for reinforcement learning and motivation, and VS hypofunction is implicated in psychiatric disorders including schizophrenia. Providing rewards or performance feedback has been shown to activate VS. Intrinsically motivated subjects performing challenging cognitive tasks are likely to engage reinforcement circuitry even in the absence of external feedback or incentives. However, such intrinsic reinforcement responses have received little attention, have not been examined in relation to behavioral performance, and have not been evaluated for impairment in neuropsychiatric disorders such as schizophrenia. Here we used fMRI to examine a challenging "old" vs. "new" visual recognition task in healthy subjects and patients with schizophrenia. Targets were unique fractal stimuli previously presented as salient distractors in a visual oddball task, producing incidental memory encoding. Based on the prediction error theory of reinforcement learning, we hypothesized that correct target recognition would activate VS in controls, and that this activation would be greater in subjects with lower expectation of responding correctly as indexed by a more conservative response bias. We also predicted these effects would be reduced in patients with schizophrenia. Consistent with these predictions, controls activated VS and other reinforcement processing regions during correct recognition, with greater VS activation in those with a more conservative response bias. Patients did not show either effect, with significant group differences suggesting hyporesponsivity in patients to internally generated feedback. These findings highlight the importance of accounting for intrinsic motivation and reward when studying cognitive tasks, and add to growing evidence of reward circuit dysfunction in schizophrenia that may impact cognition and function.

  9. Bias in little owl population estimates using playback techniques during surveys

    Directory of Open Access Journals (Sweden)

    Zuberogoitia, I.

    2011-12-01

    Full Text Available To test the efficiency of playback methods to survey little owl (Athene noctua populations we carried out two studies: (1 we recorded the replies of radio–tagged little owls to calls in a small area; (2 we recorded call broadcasts to estimate the effectiveness of the method to detect the presence of little owl. In the first study, we detected an average of 8.12 owls in the 30′ survey period, a number that is close to the real population; we also detected significant little owl movements from the initial location (before the playback to the next locations during the survey period. However, we only detected an average of 2.25 and 5.37 little owls in the first 5′ and 10′, respectively, of the survey time. In the second study, we detected 137 little owl territories in 105 positive sample units. The occupation rate was 0.35, the estimated occupancy was 0.393, and the probability of detection was 0.439. The estimated cumulative probability of detection suggests that a minimum of four sampling times would be needed in an extensive survey to detect 95% of the areas occupied by little owls.

  10. Electrophysiological mechanisms of biased response to smoking-related cues in young smokers.

    Science.gov (United States)

    Cheng, Jiadong; Guan, Yanyan; Zhang, Yajuan; Bi, Yanzhi; Bu, Limei; Li, Yangding; Shi, Sha; Liu, Peng; Lu, Xiaoqi; Yu, Dahua; Yuan, Kai

    2016-08-26

    Cigarette smoking during young adult may result in serious health issues in later life. Hence, it is extremely necessary to study the smoking neurophysiological mechanisms in this critical transitional period. However, few studies revealed the electrophysiological mechanisms of cognitive processing biases in young adult smokers. In present study, nineteen young smokers with 12h abstinent and 19 matched nonsmokers were recruited. By employing event-related potentials (ERP) measurements during a smoking cue induced craving task, electrophysiological brain responses were compared between the young adult smokers and nonsmokers. The Slow Positive Wave (SPW) amplitude of smoking-related cues was enhanced in young adult smokers compared with nonsmokers. In addition, increased P300/SPW component of smoking-related cues relative to neutral cues were found in young adult smokers. Meanwhile, a positive correlation between Cigarette Per Day (CPD) and the amplitude of ERPs wave (P300/SPW) at anterior (Fz), central (Cz) were observed in young adult smokers. Our findings provided direct electrophysiological evidence for the cognitive processing bias of smoking cue and may shed new insights into the smoking behavior in young adult smokers.

  11. Identifying attentional bias and emotional response after appearance-related stimuli exposure.

    Science.gov (United States)

    Cho, Ara; Kwak, Soo-Min; Lee, Jang-Han

    2013-01-01

    The effect of media images has been regarded as a significant variable in the construction or in the activation of body images. Individuals who have a negative body image use avoidance coping strategies to minimize damage to their body image. We identified attentional biases and negative emotional responses following exposure to body stimuli. Female university students were divided into two groups based on their use of avoidance coping strategies (high-level group: high avoidance [HA]; low-group: low avoidance [LA]), and were assigned to two different conditions (exposure to thin body pictures, ET, and exposure to oversized body pictures, EO). Results showed that the HA group paid more attention to slim bodies and reported more negative emotions than the LA group, and that the EO had more negative effects than the ET. We suggest that HAs may attend more to slim bodies as a way of avoiding overweight bodies, influenced by social pressure, and in the search for a compensation of a positive emotional balance. However, attentional bias toward slim bodies can cause an upward comparison process, leading to increased body dissatisfaction, which is the main factor in the development of eating disorders (EDs). Therefore, altering avoidance coping strategies should be considered for people at risk of EDs.

  12. Updating schematic emotional facial expressions in working memory: Response bias and sensitivity.

    Science.gov (United States)

    Tamm, Gerly; Kreegipuu, Kairi; Harro, Jaanus; Cowan, Nelson

    2017-01-01

    It is unclear if positive, negative, or neutral emotional expressions have an advantage in short-term recognition. Moreover, it is unclear from previous studies of working memory for emotional faces whether effects of emotions comprise response bias or sensitivity. The aim of this study was to compare how schematic emotional expressions (sad, angry, scheming, happy, and neutral) are discriminated and recognized in an updating task (2-back recognition) in a representative sample of birth cohort of young adults. Schematic facial expressions allow control of identity processing, which is separate from expression processing, and have been used extensively in attention research but not much, until now, in working memory research. We found that expressions with a U-curved mouth (i.e., upwardly curved), namely happy and scheming expressions, favoured a bias towards recognition (i.e., towards indicating that the probe and the stimulus in working memory are the same). Other effects of emotional expression were considerably smaller (1-2% of the variance explained)) compared to a large proportion of variance that was explained by the physical similarity of items being compared. We suggest that the nature of the stimuli plays a role in this. The present application of signal detection methodology with emotional, schematic faces in a working memory procedure requiring fast comparisons helps to resolve important contradictions that have emerged in the emotional perception literature. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. 2013 Workplace and Equal Opportunity Survey of Active Duty Members: Nonresponse Bias Report

    Science.gov (United States)

    2014-10-01

    surveys) 27 of victims (16% versus 9% for Black and 20% versus 14% for Asian) while All Others Races have the opposite effect and make up the largest...race/ethnicity negatively? ............................. e. Displayed tattoos or wore distinctive clothes which were racist...b. Sex discrimination? ................................ c. Religious discrimination? .............................. d. Other type of

  14. Skill-Biased Technological Change. Evidence from a Firm-Level Survey.

    Science.gov (United States)

    Siegel, Donald S.

    A study addressed the effects of technological change using a new, rich source of firm-level data on technology usage and labor force composition. The empirical investigation is based on a survey of Long Island manufacturers' usage of computer-integrated manufacturing systems (CIMS) or advanced manufacturing technologies (AMTs). The study also…

  15. Skill-Biased Technological Change. Evidence from a Firm-Level Survey.

    Science.gov (United States)

    Siegel, Donald S.

    A study addressed the effects of technological change using a new, rich source of firm-level data on technology usage and labor force composition. The empirical investigation is based on a survey of Long Island manufacturers' usage of computer-integrated manufacturing systems (CIMS) or advanced manufacturing technologies (AMTs). The study also…

  16. An Investigation of Response Bias Associated with Electronically Delivered Risk-Tolerance Assessment

    Directory of Open Access Journals (Sweden)

    John E. Grable

    2011-04-01

    Full Text Available

    A randomized experimental study was designed to compare risk-tolerance scores for those who completed a paper-and-pen risk-tolerance assessment instrument (i.e., the control group to those who answered the same questions using an electronic method. It was hypothesized that the possibility of an electronic bias might be present. Controlling for financial knowledge, which was positively associated with risk tolerance, men were found to report much higher risk-tolerance scores than women when responding to electronically delivered questions. Results suggest that financial therapists ought to consider this possibility as a factor that influences responses to risk assessments, especially as they incorporate additional technological evaluation tools into their practice.

  17. Working memory capacity is associated with optimal adaptation of response bias to perceptual sensitivity in emotion perception.

    Science.gov (United States)

    Lynn, Spencer K; Ibagon, Camila; Bui, Eric; Palitz, Sophie A; Simon, Naomi M; Barrett, Lisa Feldman

    2016-03-01

    Emotion perception, inferring the emotional state of another person, is a frequent judgment made under perceptual uncertainty (e.g., a scowling facial expression can indicate anger or concentration) and behavioral risk (e.g., incorrect judgment can be costly to the perceiver). Working memory capacity (WMC), the ability to maintain controlled processing in the face of competing demands, is an important component of many decisions. We investigated the association of WMC and anger perception in a task in which "angry" and "not angry" categories comprised overlapping ranges of scowl intensity, and correct and incorrect responses earned and lost points, respectively. Participants attempted to earn as many points as they could; adopting an optimal response bias would maximize decision utility. Participants with higher WMC more optimally tuned their anger perception response bias to accommodate their perceptual sensitivity (their ability to discriminate the categories) than did participants with lower WMC. Other factors that influence response bias (i.e., the relative base rate of angry vs. not angry faces and the decision costs and benefits) were ruled out as contributors to the WMC-bias relationship. Our results suggest that WMC optimizes emotion perception by contributing to perceivers' ability to adjust their response bias to account for their level of perceptual sensitivity, likely an important component of adapting emotion perception to dynamic social interactions and changing circumstances. (PsycINFO Database Record

  18. Building the analytical response in frequency domain of AC biased bolometers - Application to Planck/HFI

    Science.gov (United States)

    Sauvé, Alexandre; Montier, Ludovic

    2016-10-01

    uc(Context): Bolometers are high sensitivity detector commonly used in Infrared astronomy. The HFI instrument of the Planck satellite makes extensive use of them, but after the satellite launch two electronic related problems revealed critical. First an unexpected excess response of detectors at low optical excitation frequency for ν knowledge of detector response. However bolometers have highly nonlinear characteristics, coming from their electrical and thermal coupling making them very difficult to model. uc(Goal): We present a method to build the analytical transfer function in frequency domain which describe the voltage response of an Alternative Current (AC) biased bolometer to optical excitation, based on the standard bolometer model. This model is built using the setup of the Planck/HFI instrument and offers the major improvement of being based on a physical model rather than the currently in use had-hoc model based on Direct Current (DC) bolometer theory. uc(Method): The analytical transfer function expression will be presented in matrix form. For this purpose, we build linearized versions of the bolometer electro thermal equilibrium. A custom description of signals in frequency is used to solve the problem with linear algebra. The model performances is validated using time domain simulations. uc(Results): The provided expression is suitable for calibration and data processing. It can also be used to provide constraints for fitting optical transfer function using real data from steady state electronic response and optical response. The accurate description of electronic response can also be used to improve the ADC nonlinearity correction for quickly varying optical signals.

  19. Predicting bee community responses to land-use changes: Effects of geographic and taxonomic biases

    Science.gov (United States)

    De Palma, Adriana; Abrahamczyk, Stefan; Aizen, Marcelo A.; Albrecht, Matthias; Basset, Yves; Bates, Adam; Blake, Robin J.; Boutin, Céline; Bugter, Rob; Connop, Stuart; Cruz-López, Leopoldo; Cunningham, Saul A.; Darvill, Ben; Diekötter, Tim; Dorn, Silvia; Downing, Nicola; Entling, Martin H.; Farwig, Nina; Felicioli, Antonio; Fonte, Steven J.; Fowler, Robert; Franzén, Markus; Goulson, Dave; Grass, Ingo; Hanley, Mick E.; Hendrix, Stephen D.; Herrmann, Farina; Herzog, Felix; Holzschuh, Andrea; Jauker, Birgit; Kessler, Michael; Knight, M. E.; Kruess, Andreas; Lavelle, Patrick; Le Féon, Violette; Lentini, Pia; Malone, Louise A.; Marshall, Jon; Pachón, Eliana Martínez; McFrederick, Quinn S.; Morales, Carolina L.; Mudri-Stojnic, Sonja; Nates-Parra, Guiomar; Nilsson, Sven G.; Öckinger, Erik; Osgathorpe, Lynne; Parra-H, Alejandro; Peres, Carlos A.; Persson, Anna S.; Petanidou, Theodora; Poveda, Katja; Power, Eileen F.; Quaranta, Marino; Quintero, Carolina; Rader, Romina; Richards, Miriam H.; Roulston, T’ai; Rousseau, Laurent; Sadler, Jonathan P.; Samnegård, Ulrika; Schellhorn, Nancy A.; Schüepp, Christof; Schweiger, Oliver; Smith-Pardo, Allan H.; Steffan-Dewenter, Ingolf; Stout, Jane C.; Tonietto, Rebecca K.; Tscharntke, Teja; Tylianakis, Jason M.; Verboven, Hans A. F.; Vergara, Carlos H.; Verhulst, Jort; Westphal, Catrin; Yoon, Hyung Joo; Purvis, Andy

    2016-01-01

    Land-use change and intensification threaten bee populations worldwide, imperilling pollination services. Global models are needed to better characterise, project, and mitigate bees' responses to these human impacts. The available data are, however, geographically and taxonomically unrepresentative; most data are from North America and Western Europe, overrepresenting bumblebees and raising concerns that model results may not be generalizable to other regions and taxa. To assess whether the geographic and taxonomic biases of data could undermine effectiveness of models for conservation policy, we have collated from the published literature a global dataset of bee diversity at sites facing land-use change and intensification, and assess whether bee responses to these pressures vary across 11 regions (Western, Northern, Eastern and Southern Europe; North, Central and South America; Australia and New Zealand; South East Asia; Middle and Southern Africa) and between bumblebees and other bees. Our analyses highlight strong regionally-based responses of total abundance, species richness and Simpson's diversity to land use, caused by variation in the sensitivity of species and potentially in the nature of threats. These results suggest that global extrapolation of models based on geographically and taxonomically restricted data may underestimate the true uncertainty, increasing the risk of ecological surprises. PMID:27509831

  20. Cool Core Bias in Sunyaev-Zel'dovich Galaxy Cluster Surveys

    CERN Document Server

    Lin, Henry W; Benson, Bradford; Miller, Eric

    2015-01-01

    Sunyaev-Zeldovich (SZ) surveys find massive clusters of galaxies by measuring the inverse Compton scattering of cosmic microwave background off of intra-cluster gas. The cluster selection function from such surveys is expected to be nearly independent of redshift and cluster astrophysics. In this work, we estimate the effect on the observed SZ signal of centrally-peaked gas density profiles (cool cores) and radio emission from the brightest cluster galaxy (BCG) by creating mock observations of a sample of clusters that span the observed range of classical cooling rates and radio luminosities. For each cluster, we make simulated SZ observations by the South Pole Telescope and characterize the cluster selection function, but note that our results are broadly applicable to other SZ surveys. We find that the inclusion of a cool core can cause a change in the measured SPT significance of a cluster between 0.01% - 10% at z > 0.3, increasing with cuspiness of the cool core and angular size on the sky of the cluster ...

  1. Are self-reports of smoking rate biased? Evidence from the Second National Health and Nutrition Examination Survey.

    Science.gov (United States)

    Klesges, R C; Debon, M; Ray, J W

    1995-10-01

    This study determined evidence for digit preference in self-reports of smoking in the Second National Health and Nutrition Examination Survey (NHANES II). Subjects were 4275 adult smokers. Self-reports of smoking showed a marked degree of digit preference, with the vast majority of smokers reporting in multiples of 10 cigarettes per day. When number per day was compared to an objective measure of smoking exposure (carboxyhemoglobin; n = 2070) the distribution was found to be significantly assymetrical. Analysis of the distribution of COHb and various levels of number per day indicates that the differences in distribution are not due to variability in COHb. Heavier smokers, Caucasians, and those with less education were more likely to report a digit preference than lighter smokers. African-Americans, and those with more education. Results suggest that self-reports of number of cigarettes per day may be biased towards round numbers (particularly 20 cigarettes per day). Implications for assessment of smoking behavior are discussed.

  2. Predicting survey responses: how and why semantics shape survey statistics on organizational behaviour.

    Science.gov (United States)

    Arnulf, Jan Ketil; Larsen, Kai Rune; Martinsen, Øyvind Lund; Bong, Chih How

    2014-01-01

    Some disciplines in the social sciences rely heavily on collecting survey responses to detect empirical relationships among variables. We explored whether these relationships were a priori predictable from the semantic properties of the survey items, using language processing algorithms which are now available as new research methods. Language processing algorithms were used to calculate the semantic similarity among all items in state-of-the-art surveys from Organisational Behaviour research. These surveys covered areas such as transformational leadership, work motivation and work outcomes. This information was used to explain and predict the response patterns from real subjects. Semantic algorithms explained 60-86% of the variance in the response patterns and allowed remarkably precise prediction of survey responses from humans, except in a personality test. Even the relationships between independent and their purported dependent variables were accurately predicted. This raises concern about the empirical nature of data collected through some surveys if results are already given a priori through the way subjects are being asked. Survey response patterns seem heavily determined by semantics. Language algorithms may suggest these prior to administering a survey. This study suggests that semantic algorithms are becoming new tools for the social sciences, opening perspectives on survey responses that prevalent psychometric theory cannot explain.

  3. Predicting survey responses: how and why semantics shape survey statistics on organizational behaviour.

    Directory of Open Access Journals (Sweden)

    Jan Ketil Arnulf

    Full Text Available Some disciplines in the social sciences rely heavily on collecting survey responses to detect empirical relationships among variables. We explored whether these relationships were a priori predictable from the semantic properties of the survey items, using language processing algorithms which are now available as new research methods. Language processing algorithms were used to calculate the semantic similarity among all items in state-of-the-art surveys from Organisational Behaviour research. These surveys covered areas such as transformational leadership, work motivation and work outcomes. This information was used to explain and predict the response patterns from real subjects. Semantic algorithms explained 60-86% of the variance in the response patterns and allowed remarkably precise prediction of survey responses from humans, except in a personality test. Even the relationships between independent and their purported dependent variables were accurately predicted. This raises concern about the empirical nature of data collected through some surveys if results are already given a priori through the way subjects are being asked. Survey response patterns seem heavily determined by semantics. Language algorithms may suggest these prior to administering a survey. This study suggests that semantic algorithms are becoming new tools for the social sciences, opening perspectives on survey responses that prevalent psychometric theory cannot explain.

  4. Fighting bias with statistics: Detecting gender differences in responses to items on a preschool science assessment

    Science.gov (United States)

    Greenberg, Ariela Caren

    Differential item functioning (DIF) and differential distractor functioning (DDF) are methods used to screen for item bias (Camilli & Shepard, 1994; Penfield, 2008). Using an applied empirical example, this mixed-methods study examined the congruency and relationship of DIF and DDF methods in screening multiple-choice items. Data for Study I were drawn from item responses of 271 female and 236 male low-income children on a preschool science assessment. Item analyses employed a common statistical approach of the Mantel-Haenszel log-odds ratio (MH-LOR) to detect DIF in dichotomously scored items (Holland & Thayer, 1988), and extended the approach to identify DDF (Penfield, 2008). Findings demonstrated that the using MH-LOR to detect DIF and DDF supported the theoretical relationship that the magnitude and form of DIF and are dependent on the DDF effects, and demonstrated the advantages of studying DIF and DDF in multiple-choice items. A total of 4 items with DIF and DDF and 5 items with only DDF were detected. Study II incorporated an item content review, an important but often overlooked and under-published step of DIF and DDF studies (Camilli & Shepard). Interviews with 25 female and 22 male low-income preschool children and an expert review helped to interpret the DIF and DDF results and their comparison, and determined that a content review process of studied items can reveal reasons for potential item bias that are often congruent with the statistical results. Patterns emerged and are discussed in detail. The quantitative and qualitative analyses were conducted in an applied framework of examining the validity of the preschool science assessment scores for evaluating science programs serving low-income children, however, the techniques can be generalized for use with measures across various disciplines of research.

  5. Continuous carryover of temporal context dissociates response bias from perceptual influence for duration.

    Directory of Open Access Journals (Sweden)

    Martin Wiener

    Full Text Available Recent experimental evidence suggests that the perception of temporal intervals is influenced by the temporal context in which they are presented. A longstanding example is the time-order-error, wherein the perception of two intervals relative to one another is influenced by the order in which they are presented. Here, we test whether the perception of temporal intervals in an absolute judgment task is influenced by the preceding temporal context. Human subjects participated in a temporal bisection task with no anchor durations (partition method. Intervals were demarcated by a Gaussian blob (visual condition or burst of white noise (auditory condition that persisted for one of seven logarithmically spaced sub-second intervals. Crucially, the order in which stimuli were presented was first-order counterbalanced, allowing us to measure the carryover effect of every successive combination of intervals. The results demonstrated a number of distinct findings. First, the perception of each interval was biased by the prior response, such that each interval was judged similarly to the preceding trial. Second, the perception of each interval was also influenced by the prior interval, such that perceived duration shifted away from the preceding interval. Additionally, the effect of decision bias was larger for visual intervals, whereas auditory intervals engendered greater perceptual carryover. We quantified these effects by designing a biologically-inspired computational model that measures noisy representations of time against an adaptive memory prior while simultaneously accounting for uncertainty, consistent with a Bayesian heuristic. We found that our model could account for all of the effects observed in human data. Additionally, our model could only accommodate both carryover effects when uncertainty and memory were calculated separately, suggesting separate neural representations for each. These findings demonstrate that time is susceptible to

  6. The effects of social desirability response bias on STAXI-2 profiles in a clinical forensic sample.

    Science.gov (United States)

    McEwan, Troy E; Davis, Michael R; MacKenzie, Rachel; Mullen, Paul E

    2009-11-01

    This study investigated the proposition that the 'State-trait anger expression inventory' (2nd ed.; STAXI-2) is susceptible to impression management (IM) and Self-Deceptive Enhancement (SDE) in clinical forensic populations. It was hypothesized that individuals engaging in IM would report significantly lower levels of trait anger, external expression of anger, and internal expression of anger on the STAXI-2. Those reporting above average SDE were predicted to claim higher levels of anger control. A between-groups design was used, comparing STAXI-2 scores of individuals who reported high levels of IM and SDE to those who did not. One-hundred and fifty-nine male patients of a community forensic mental health service, referred for assessment of stalking behaviours, completed the STAXI-2 and Paulhus Deception Scales (PDS). Individuals engaging in high levels of IM and SDE were compared to low scorers in regard to STAXI-2 scales using Mann-Whitney U tests. Individuals engaging in IM had significantly lower levels of reported trait anger, outward expression of anger, and inward expression of anger, and higher levels of anger control. Similar results were found with the SDE scale, although the magnitude of the effect was smaller and not apparent on all subscales. The STAXI-2 was vulnerable to social desirability response bias in this sample of forensic clients. Where the STAXI-2 is used as a basis for treatment recommendations and decisions, it should be administered and interpreted in conjunction with a recognized measure of such bias to improve validity.

  7. Correcting cosmological parameter biases for all redshift surveys induced by estimating and reweighting redshift distributions

    Science.gov (United States)

    Rau, Markus Michael; Hoyle, Ben; Paech, Kerstin; Seitz, Stella

    2017-04-01

    Photometric redshift uncertainties are a major source of systematic error for ongoing and future photometric surveys. We study different sources of redshift error caused by choosing a suboptimal redshift histogram bin width and propose methods to resolve them. The selection of a too large bin width is shown to oversmooth small-scale structure of the radial distribution of galaxies. This systematic error can significantly shift cosmological parameter constraints by up to 6σ for the dark energy equation-of-state parameter w. Careful selection of bin width can reduce this systematic by a factor of up to 6 as compared with commonly used current binning approaches. We further discuss a generalized resampling method that can correct systematic and statistical errors in cosmological parameter constraints caused by uncertainties in the redshift distribution. This can be achieved without any prior assumptions about the shape of the distribution or the form of the redshift error. Our methodology allows photometric surveys to obtain unbiased cosmological parameter constraints using a minimum number of spectroscopic calibration data. For a DES-like galaxy clustering forecast, we obtain unbiased results with respect to errors caused by suboptimal histogram bin width selection, using only 5k representative spectroscopic calibration objects per tomographic redshift bin.

  8. Manipulations of cognitive strategies and intergroup relationships reduce the racial bias in empathic neural responses.

    Science.gov (United States)

    Sheng, Feng; Han, Shihui

    2012-07-16

    Social relationships affect empathy in humans such that empathic neural responses to perceived pain were stronger to racial in-group members than to racial out-group members. Why does the racial bias in empathy (RBE) occur and how can we reduce it? We hypothesized that perceiving an other-race person as a symbol of a racial group, rather than as an individual, decreases references to his/her personal situation and weakens empathy for that person. This hypothesis predicts that individuating other-race persons by increasing attention to each individual's feelings or enclosing other-race individuals within one's own social group can reduce the RBE by increasing empathic neural responses to other-race individuals. In Experiment 1, we recorded event related brain potentials from Chinese adults as they made race judgments on Asian and Caucasian faces with pain or neutral expressions. We identified the RBE by showing that, relative to neutral expressions, pain expressions increased neural responses at 128-188 ms after stimulus onset over the frontal/central brain regions, and this effect was evident for same-race faces but not for other-race faces. Experiments 2 and 3 found that paying attention to observed individual's feelings of pain and including other-race individuals in one's own team for competitions respectively eliminated the RBE by increasing neural responses to pain expressions in other-race faces. Our results indicate that the RBE is not inevitable and that manipulations of both cognitive strategies and intergroup relationships can decrease RBE-related brain activity.

  9. Examination of various WMS-III logical memory scores in the assessment of response bias.

    Science.gov (United States)

    Bortnik, Kirsty E; Boone, Kyle B; Marion, Sarah D; Amano, Stacy; Ziegler, Elizabeth; Cottingham, Maria E; Victor, Tara L; Zeller, Michelle A

    2010-02-01

    The assessment of response validity during neuropsychological evaluation is an integral part of the testing process. Research has increasingly focused on the use of "embedded" effort measures (derived from standard neuropsychological tasks) because they do not require additional administration time and are less likely to be identified as effort indicators by test takers because of their primary focus as measures of cognitive function. The current study examined the clinical utility of various WMS-III Logical Memory scores in detecting response bias, as well as the Rarely Missed Index, an embedded effort indicator derived from the WMS-III Logical Memory Delayed Recognition subtest. The Rarely Missed Index cut-off only identified 24.1% of 63 non-credible participants (at >/=90% specificity in 125 credible patients), and cut-offs for other Logical Memory variables were in fact found to be more sensitive to non-credible performance. A new indicator, consisting of the weighted combination of the two most sensitive Logical Memory subtest scores (Logical Memory II raw score and Logical Memory Delayed Recognition raw score), was associated with 53% to 60% sensitivity, and thus may be an effective adjunct when utilized in conjunction with other validated effort indicators and collateral information in identifying non-credible performance.

  10. Effect of DC Bias on Dielectric Response in Relaxor Ferroelectric Terpolymer Films

    Science.gov (United States)

    Tian, L.; Sun, J.; Wang, J. L.; Li, Y. P.

    2017-06-01

    The permittivity as a function of temperature and dc bias in the poly(vinylindene fluoride-trifluorethylene-chlorofluoroethylene) [P(VDF-TrFE-CFE)] terpolymer was measured and analyzed using both the Vogel-Fulcher and universal Curie-Weiss law. The decreased permittivity with increasing dc bias has been observed. The lower permittivity in dc bias is due to the suppressed diffusion of phase transition rather than the nonlinear dielectric contribution. Furthermore, the suppression of phase diffusion can be explained by the molecular conformation conversion in dc bias.

  11. Correcting cosmological parameter biases for all redshift surveys induced by estimating and reweighting redshift distributions

    CERN Document Server

    Rau, Markus Michael; Paech, Kerstin; Seitz, Stella

    2016-01-01

    Photometric redshift uncertainties are a major source of systematic error for ongoing and future photometric surveys. We study different sources of redshift error caused by common suboptimal binning techniques and propose methods to resolve them. The selection of a too large bin width is shown to oversmooth small scale structure of the radial distribution of galaxies. This systematic error can significantly shift cosmological parameter constraints by up to $6 \\, \\sigma$ for the dark energy equation of state parameter $w$. Careful selection of bin width can reduce this systematic by a factor of up to 6 as compared with commonly used current binning approaches. We further discuss a generalised resampling method that can correct systematic and statistical errors in cosmological parameter constraints caused by uncertainties in the redshift distribution. This can be achieved without any prior assumptions about the shape of the distribution or the form of the redshift error. Our methodology allows photometric surve...

  12. Consequences of CCD imperfections for cosmology determined by weak lensing surveys: From laboratory measurements to cosmological parameter bias

    CERN Document Server

    Okura, Yuki; May, Morgan; Plazas, Andrés A; Tamagawa, Toru

    2016-01-01

    Weak gravitational lensing causes subtle changes in the apparent shapes of galaxies due to the bending of light by the gravity of foreground masses. By measuring the shapes of large numbers of galaxies (millions in recent surveys, up to tens of billions in future surveys) we can infer the parameters that determine cosmology. Imperfections in the detectors used to record images of the sky can introduce changes in the apparent shape of galaxies, which in turn can bias the inferred cosmological parameters. In this paper we consider the effect of two widely discussed sensor imperfections: tree-rings, due to impurity gradients which cause transverse electric fields in the Charge-Coupled Devices (CCD), and pixel-size variation, due to periodic CCD fabrication errors. These imperfections can be observed when the detectors are subject to uniform illumination (flat field images). We develop methods to determine the spurious shear and convergence (due to the imperfections) from the flat-field images. We calculate how t...

  13. Self-responsibility and the self-serving bias: an fMRI investigation of causal attributions.

    Science.gov (United States)

    Blackwood, N J; Bentall, R P; ffytche, D H; Simmons, A; Murray, R M; Howard, R J

    2003-10-01

    We use causal attributions to infer the most likely cause of events in the social world. Internal attributions imply self-responsibility for events. The self-serving bias describes the tendency of normal subjects to attribute the causation of positive events internally ("I am responsible em leader ") and negative events externally ("Other people or situational factors are responsible em leader "). The self-serving bias has been assumed to serve a positive motivational function by enhancing self-esteem. Abnormalities of attributional style have been implicated in both depression and psychosis. We examined the neural basis of both self-responsibility and the self-serving bias using functional magnetic resonance imaging during the performance of attributional decision tasks. We found that the determination of self-responsibility recruits areas previously implicated in action simulation (bilateral premotor cortex and cerebellum), suggesting that such higher order social cognition is related to simpler internal models of goal-directed action. The dorsal striatum, previously implicated in motivated behavior, mediates the self-serving bias.

  14. 25-year trends and socio-demographic differences in response rates: Finnish adult health behaviour survey.

    Science.gov (United States)

    Tolonen, Hanna; Helakorpi, Satu; Talala, Kirsi; Helasoja, Ville; Martelin, Tuija; Prättälä, Ritva

    2006-01-01

    When estimating population level changes in health indicators, the declining response rate, especially if also the characteristics of non-respondents are changing may bias the outcome. There is evidence that survey response rates are declining in many countries. It is also known that respondents and non-respondents differ in their socio-economic and demographic status as well as in their health and health behaviours. There is no information about the changes in the differences between respondents and non-respondents over time. Our purpose was to investigate the changes over time in the differences between respondents and non-respondents in respect to their sex, age, marital status and educational level. The data from the Finnish Adult Health Behaviour Survey (1978-2002) was used. The response rate declined over the past 25 years for both men and women in all age groups. The decline was faster among men than women, and also faster in younger age groups than older age groups. There is a marked difference in the response rate between married and non-married persons but it did not change over time. Also the response rate between different educational levels differed for both men and women, and this difference increased over the years. The declining response rate and at the same time occurring change in the non-respondent characteristics will decrease the representativeness of the results, limit the comparability of the results with other surveys, increase the bias of the trend estimates and limit the comparability of the results between population groups.

  15. Disfluencies and gaze aversion in unreliable responses to survey questions

    NARCIS (Netherlands)

    Schober, Michael F.; Conrad, Frederick G.; Dijkstra, Wil; Ongena, Yfke P.

    2012-01-01

    When survey respondents answer survey questions, they can also produce "paradata" (Couper 2000, 2008): behavioral evidence about their response process. The study reported here demonstrates that two kinds of respondent paradata - fluency of speech and gaze direction during answers - identify answers

  16. Living with Smartphones: Does Completion Device Affect Survey Responses?

    Science.gov (United States)

    Lambert, Amber D.; Miller, Angie L.

    2015-01-01

    With the growing reliance on tablets and smartphones for internet access, understanding the effects of completion device on online survey responses becomes increasing important. This study uses data from the Strategic National Arts Alumni Project, a multi-institution online alumni survey designed to obtain knowledge of arts education, to explore…

  17. Living with Smartphones: Does Completion Device Affect Survey Responses?

    Science.gov (United States)

    Lambert, Amber D.; Miller, Angie L.

    2015-01-01

    With the growing reliance on tablets and smartphones for internet access, understanding the effects of completion device on online survey responses becomes increasing important. This study uses data from the Strategic National Arts Alumni Project, a multi-institution online alumni survey designed to obtain knowledge of arts education, to explore…

  18. A Comparison of Web-Based and Paper-Based Survey Methods: Testing Assumptions of Survey Mode and Response Cost

    Science.gov (United States)

    Greenlaw, Corey; Brown-Welty, Sharon

    2009-01-01

    Web-based surveys have become more prevalent in areas such as evaluation, research, and marketing research to name a few. The proliferation of these online surveys raises the question, how do response rates compare with traditional surveys and at what cost? This research explored response rates and costs for Web-based surveys, paper surveys, and…

  19. A Comparison of Web-Based and Paper-Based Survey Methods: Testing Assumptions of Survey Mode and Response Cost

    Science.gov (United States)

    Greenlaw, Corey; Brown-Welty, Sharon

    2009-01-01

    Web-based surveys have become more prevalent in areas such as evaluation, research, and marketing research to name a few. The proliferation of these online surveys raises the question, how do response rates compare with traditional surveys and at what cost? This research explored response rates and costs for Web-based surveys, paper surveys, and…

  20. Canine sense and sensibility: tipping points and response latency variability as an optimism index in a canine judgement bias assessment.

    Directory of Open Access Journals (Sweden)

    Melissa J Starling

    Full Text Available Recent advances in animal welfare science used judgement bias, a type of cognitive bias, as a means to objectively measure an animal's affective state. It is postulated that animals showing heightened expectation of positive outcomes may be categorised optimistic, while those showing heightened expectations of negative outcomes may be considered pessimistic. This study pioneers the use of a portable, automated apparatus to train and test the judgement bias of dogs. Dogs were trained in a discrimination task in which they learned to touch a target after a tone associated with a lactose-free milk reward and abstain from touching the target after a tone associated with water. Their judgement bias was then probed by presenting tones between those learned in the discrimination task and measuring their latency to respond by touching the target. A Cox's Proportional Hazards model was used to analyse censored response latency data. Dog and Cue both had a highly significant effect on latency and risk of touching a target. This indicates that judgement bias both exists in dogs and differs between dogs. Test number also had a significant effect, indicating that dogs were less likely to touch the target over successive tests. Detailed examination of the response latencies revealed tipping points where average latency increased by 100% or more, giving an indication of where dogs began to treat ambiguous cues as predicting more negative outcomes than positive ones. Variability scores were calculated to provide an index of optimism using average latency and standard deviation at cues after the tipping point. The use of a mathematical approach to assessing judgement bias data in animal studies offers a more detailed interpretation than traditional statistical analyses. This study provides proof of concept for the use of an automated apparatus for measuring cognitive bias in dogs.

  1. Canine sense and sensibility: tipping points and response latency variability as an optimism index in a canine judgement bias assessment.

    Science.gov (United States)

    Starling, Melissa J; Branson, Nicholas; Cody, Denis; Starling, Timothy R; McGreevy, Paul D

    2014-01-01

    Recent advances in animal welfare science used judgement bias, a type of cognitive bias, as a means to objectively measure an animal's affective state. It is postulated that animals showing heightened expectation of positive outcomes may be categorised optimistic, while those showing heightened expectations of negative outcomes may be considered pessimistic. This study pioneers the use of a portable, automated apparatus to train and test the judgement bias of dogs. Dogs were trained in a discrimination task in which they learned to touch a target after a tone associated with a lactose-free milk reward and abstain from touching the target after a tone associated with water. Their judgement bias was then probed by presenting tones between those learned in the discrimination task and measuring their latency to respond by touching the target. A Cox's Proportional Hazards model was used to analyse censored response latency data. Dog and Cue both had a highly significant effect on latency and risk of touching a target. This indicates that judgement bias both exists in dogs and differs between dogs. Test number also had a significant effect, indicating that dogs were less likely to touch the target over successive tests. Detailed examination of the response latencies revealed tipping points where average latency increased by 100% or more, giving an indication of where dogs began to treat ambiguous cues as predicting more negative outcomes than positive ones. Variability scores were calculated to provide an index of optimism using average latency and standard deviation at cues after the tipping point. The use of a mathematical approach to assessing judgement bias data in animal studies offers a more detailed interpretation than traditional statistical analyses. This study provides proof of concept for the use of an automated apparatus for measuring cognitive bias in dogs.

  2. Attrition in the Austrian Generations and Gender Survey: Is there a bias by fertility-relevant aspects?

    Directory of Open Access Journals (Sweden)

    Isabella Buber-Ennser

    2014-08-01

    Full Text Available Background: In longitudinal research the loss of sample members between waves is a possible source of bias. It is therefore crucial to analyse attrition. Objective: This paper analyses attrition in a longitudinal study on family and fertility, by distinguishing between attrition due to non-contact and attrition due to non-cooperation. Methods: Based on the first two waves of the Austrian Generations and Gender Survey, the two components of attrition are studied separately by using bivariate as well as multivariate methods. Moreover, overall dropout - the combination of both components - isanalysed. Apart from various socio-economic characteristics and data collection information, the study focuses on fertility-relevant variables such as fecundity, fertility intentions, sexual orientation, and traditional attitudes. Results: Fecundity, fertility intentions, and homosexual relationships are associated with higher attrition due to non-cooperation in bivariate analyses, but have no explanatory power inthe multivariate model. Pregnancy and traditional attitudes towards marriage are associated with significantly lower attrition due to non-cooperation in the multivariate context. Overall dropout is significantly lower only among persons with traditionalattitudes towards marriage, although small in size and statistical significance. Moreover, various individual and regional characteristics are significantly associated with dropout, with differences between attrition due to non-contact and attrition due to non-cooperation. Conclusions: Detailed insights into attrition are not only important when using longitudinal data and interpreting results, but also for the design of future data collections. The Austrian GGS panel has a relatively low dropout (22Š and is affected by a small bias towards familyoriented persons as well as less-educated respondents and persons with migrationbackgrounds, but the data can be used without concern about selectivity.

  3. Further Validation of the MMPI-2 And MMPI-2-RF Response Bias Scale: Findings from Disability and Criminal Forensic Settings

    Science.gov (United States)

    Wygant, Dustin B.; Sellbom, Martin; Gervais, Roger O.; Ben-Porath, Yossef S.; Stafford, Kathleen P.; Freeman, David B.; Heilbronner, Robert L.

    2010-01-01

    The present study extends the validation of the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) and the Minnesota Multiphasic Personality Inventory-2 Restructured Form (MMPI-2-RF) Response Bias Scale (RBS; R. O. Gervais, Y. S. Ben-Porath, D. B. Wygant, & P. Green, 2007) in separate forensic samples composed of disability claimants and…

  4. Elementary Pre-Service Teachers' Response-Shift Bias: Self-Efficacy and Attitudes toward Science

    Science.gov (United States)

    Cartwright, Tina J.; Atwood, Jon

    2014-01-01

    Response-shift bias occurs when participants' initial constructs, such as self-efficacy in teaching science, are incomplete because they do not fully conceptualize something they have yet to experience. This study examines whether elementary pre-service teachers can consistently evaluate constructs such as self-efficacy and attitudes toward…

  5. A protocol to identify and minimise selection and information bias in abattoir surveys estimating prevalence, using Fasciola hepatica as an example.

    Science.gov (United States)

    Carroll, Rebecca I; Forbes, Andrew; Graham, David A; Messam, Locksley L McV

    2017-09-01

    Abattoir surveys and findings from post-mortem meat inspection are commonly used to estimate infection or disease prevalence in farm animal populations. However, the function of an abattoir is to slaughter animals for human consumption, and the collection of information on animal health for research purposes is a secondary objective. This can result in methodological shortcomings leading to biased prevalence estimates. Selection bias can occur when the study population as obtained from the abattoir is not an accurate representation of the target population. Virtually all of the tests used in abattoir surveys to detect infections or diseases that impact animal health are imperfect, leading to errors in identifying the outcome of interest and consequently, information bias. Examination of abattoir surveys estimating prevalence in the literature reveals shortcomings in the methods used in these studies. While the STROBE-Vet statement provides clear guidance on the reporting of observational research, we have not found any guidelines in the literature advising researchers on how to conduct abattoir surveys. This paper presents a protocol in two flowcharts to help researchers (regardless of their background in epidemiology) to first identify, and, where possible, minimise biases in abattoir surveys estimating prevalence. Flowchart 1 examines the identification of the target population and the appropriate study population while Flowchart 2 guides the researcher in identifying, and, where possible, correcting potential sources of outcome misclassification. Examples of simple sensitivity analyses are also presented which approximate the likely uncertainty in prevalence estimates due to systematic errors. Finally, the researcher is directed to outline any limitations of the study in the discussion section of the paper. This protocol makes it easier to conduct an abattoir survey using sound methods, identifying and, where possible, minimizing biases. Copyright © 2017

  6. De-biased populations of Kuiper belt objects from the deep ecliptic survey

    Energy Technology Data Exchange (ETDEWEB)

    Adams, E. R.; Benecchi, S. D. [Planetary Science Institute, 1700 East Fort Lowell, Suite 106, Tucson, AZ 85719 (United States); Gulbis, A. A. S. [The Southern African Large Telescope and South African Astronomical Observatory, Cape Town, 7935 (South Africa); Elliot, J. L. [Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States); Buie, M. W. [Southwest Research Institute, 6220 Culebra Road, San Antonio, TX 78238 (United States); Trilling, D. E. [Department of Physics and Astronomy, Northern Arizona University, S San Francisco Street, Flagstaff, AZ 86011 (United States); Wasserman, L. H. [Lowell Observatory, 1400 W. Mars Hill Road, Flagstaff, AZ 86001 (United States)

    2014-09-01

    The Deep Ecliptic Survey (DES) was a survey project that discovered hundreds of Kuiper Belt objects from 1998 to 2005. Extensive follow-up observations of these bodies has yielded 304 objects with well-determined orbits and dynamical classifications into one of several categories: Classical, Scattered, Centaur, or 16 mean-motion resonances with Neptune. The DES search fields are well documented, enabling us to calculate the probability on each frame of detecting an object with its particular orbital parameters and absolute magnitude at a randomized point in its orbit. The detection probabilities range from a maximum of 0.32 for the 3:2 resonant object 2002 GF {sub 32} to a minimum of 1.5 × 10{sup –7} for the faint Scattered object 2001 FU {sub 185}. By grouping individual objects together by dynamical classes, we can estimate the distributions of four parameters that define each class: semimajor axis, eccentricity, inclination, and object size. The orbital element distributions (a, e, and i) were fit to the largest three classes (Classical, 3:2, and Scattered) using a maximum likelihood fit. Using the absolute magnitude (H magnitude) as a proxy for the object size, we fit a power law to the number of objects versus H magnitude for eight classes with at least five detected members (246 objects). The Classical objects are best fit with a power-law slope of α = 1.02 ± 0.01 (observed from 5 ≤ H ≤ 7.2). Six other dynamical classes (Scattered plus five resonances) have consistent magnitude distribution slopes with the Classicals, provided that the absolute number of objects is scaled. Scattered objects are somewhat more numerous than Classical objects, while there are only a quarter as many 3:2 objects as Classicals. The exception to the power law relation is the Centaurs, which are non-resonant objects with perihelia closer than Neptune and therefore brighter and detectable at smaller sizes. Centaurs were observed from 7.5 < H < 11, and that population is best

  7. Persistent affective biases in human amygdala response following implicit priming with negative emotion concepts.

    Science.gov (United States)

    Pichon, Swann; Rieger, Sebastian W; Vuilleumier, Patrik

    2012-09-01

    To what extent do past experiences shape our behaviors, perceptions, and thoughts even without explicit knowledge of these influences? Behavioral research has demonstrated that various cognitive processes can be influenced by conceptual representations implicitly primed during a preceding and unrelated task. Here we investigated whether emotion processing might also be influenced by prior incidental exposure to negative semantic material and which neural substrates would mediate these effects. During a first (priming) task, participants performed a variant of the hangman game with either negative or neutral emotion-laden words. Subsequently, they performed a second, unrelated visual task with fearful and neutral faces presented at attended or unattended locations. Participants were generally not aware of any relationships between the two tasks. We found that priming with emotional words enhanced amygdala sensitivity to faces in the subsequent visual task, while decreasing discriminative responses to threat. Furthermore, the magnitude of the induced bias in behavior and amygdala activation was predicted by the effectiveness of semantic access observed in the priming task. This demonstrates that emotional processing can be modulated by implicit influence of environmental information processed at an earlier time, independently of volitional control.

  8. Bias in medicine: a survey of medical student attitudes towards HIV-positive and marginalized patients in Russia, 2010

    Directory of Open Access Journals (Sweden)

    Damir A Bikmukhametov

    2012-09-01

    Full Text Available Background: Russia has a substantial HIV epidemic which is poised to escalate in the coming years. The increases in prevalence of HIV will result in increased healthcare needs by a medical system with limited experience with HIV. A healthcare provider's attitude towards a patient plays a significant role in determining the patient's health-related behaviours and medical outcomes. Previous studies have identified negative attitudes of medical students towards people living with HIV. Studying the prevalence of such attitudes is of particular interest, as medical students represent the future workforce and also as the schooling years present a unique opportunity to nurture bias-free healthcare providers. The study measures prevalence of prejudicial attitudes towards HIV-positive and HIV-negative patients who belong to marginalized subgroups. Methods: The cross-sectional survey was conducted among medical students of a Russian medical university. Of 500 students surveyed, 436 provided sufficient data to be included in the analysis. Prejudicial attitudes were defined as reluctance to provide medical care to a specified hypothetical patient. Nine hypothetical HIV-positive and HIV-negative patients were proposed: physicians, injecting drug users, commercial sex workers, men who have sex with men and a patient HIV-positive due to blood transfusion. A log-binomial regression solved using generalized estimating equations was utilized to identify factors associated with reluctance to treat. Results: Prevalence of reluctance to provide medical care to HIV-positive patients in marginalized subgroups was high (ranging from 26.4% up to 71.9%, compared to a maximum of 7.5% if a patient was an HIV-negative physician. Students in their clinical years reported more negative attitudes than preclinical students. In general, female students were less willing to provide care than their male counterparts. Conclusions: Prejudicial attitudes about HIV-positive patients

  9. Assessing threat responses towards the symptoms and diagnosis of schizophrenia using visual perceptual biases.

    Science.gov (United States)

    Heenan, Adam; Best, Michael W; Ouellette, Sarah J; Meiklejohn, Erin; Troje, Nikolaus F; Bowie, Christopher R

    2014-10-01

    Stigma towards individuals diagnosed with schizophrenia continues despite increasing public knowledge about the disorder. Questionnaires are used almost exclusively to assess stigma despite self-report biases affecting their validity. The purpose of this experiment was to implicitly assess stigma towards individuals with schizophrenia by measuring visual perceptual biases immediately after participants conversed with a confederate. We manipulated both the diagnostic label attributed to the confederate (peer vs. schizophrenia) and the presence of behavioural symptoms (present vs. absent). Immediately before and after conversing with the confederate, we measured participants' facing-the-viewer (FTV) biases (the preference to perceive depth-ambiguous stick-figure walkers as facing towards them). As studies have suggested that the FTV bias is sensitive to the perception of threat, we hypothesized that FTV biases would be greater after participants conversed with someone that they believed had schizophrenia, and also after they conversed with someone who presented symptoms of schizophrenia. We found partial support for these hypotheses. Participants had significantly greater FTV biases in the Peer Label/Symptoms Present condition. Interestingly, while FTV biases were lowest in the Schizophrenia Label/Symptoms Present condition, participants in this condition were most likely to believe that people with schizophrenia should face social restrictions. Our findings support that both implicit and explicit beliefs help develop and sustain stigma.

  10. Measuring the Accuracy of Survey Responses using Administrative Register Data

    DEFF Research Database (Denmark)

    Kreiner, Claus Thustrup; Lassen, David Dreyer; Leth-Petersen, Søren

    2015-01-01

    This paper shows how Danish administrative register data can be combined with survey data at the person level and be used to validate information collected in the survey. Register data are collected by automatic third party reporting and the potential errors associated with the two data sources...... are therefore plausibly orthogonal. Two examples are given to illustrate the potential of combining survey and register data. In the first example expenditure survey records with information about total expenditure are merged with income tax records holding information about income and wealth. Income and wealth...... data are used to impute total expenditure which is then compared to the survey measure. Results suggest that the two measures match each other well on average. In the second example we compare responses to a one-shot recall question about total gross personal income ¿collected in another survey...

  11. Large self-biased magnetoelectric response in four-phase heterostructure with multiple low-frequency peaks

    Science.gov (United States)

    Zhang, Hao; Lu, Caijiang; Sun, Zhixue

    2015-01-01

    This paper develops a self-biased magnetoelectric (ME) heterostructure FeCuNbSiB/Terfenol-D/Be-bronze/Pb(Zr,Ti)O3 (PZT) by sandwiching a nonmagnetic elastic Be-bronze plate between an piezoelectric PZT plate and a magnetization-graded FeCuNbSiB/Terfenol-D layer. The Be-bronze plate severs as the resonance frequency determining element of the ME heterostructure. By using the magnetization-graded magnetostrictive layer and the elastic Be-bronze plate, seven large peaks of ME response with magnitudes of 0.3-10 (V/cm Oe) in 1-70 kHz range are observed at zero-biased magnetic field. This demonstrates that the proposed multi-peak self-biased heterostructure may be useful for multifunctional devices such as multi-frequency energy harvesters or low-frequency ac magnetic field sensors.

  12. Response rate, response time, and economic costs of survey research: A randomized trial of practicing pharmacists.

    Science.gov (United States)

    Hardigan, Patrick C; Popovici, Ioana; Carvajal, Manuel J

    2016-01-01

    There is a gap between increasing demands from pharmacy journals, publishers, and reviewers for high survey response rates and the actual responses often obtained in the field by survey researchers. Presumably demands have been set high because response rates, times, and costs affect the validity and reliability of survey results. Explore the extent to which survey response rates, average response times, and economic costs are affected by conditions under which pharmacist workforce surveys are administered. A random sample of 7200 U.S. practicing pharmacists was selected. The sample was stratified by delivery method, questionnaire length, item placement, and gender of respondent for a total of 300 observations within each subgroup. A job satisfaction survey was administered during March-April 2012. Delivery method was the only classification showing significant differences in response rates and average response times. The postal mail procedure accounted for the highest response rates of completed surveys, but the email method exhibited the quickest turnaround. A hybrid approach, consisting of a combination of postal and electronic means, showed the least favorable results. Postal mail was 2.9 times more cost effective than the email approach and 4.6 times more cost effective than the hybrid approach. Researchers seeking to increase practicing pharmacists' survey participation and reduce response time and related costs can benefit from the analytical procedures tested here. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. In Search of Motivation for the Business Survey Response Task

    NARCIS (Netherlands)

    Torres van Grinsven, Vanessa; Bolko, Irena; Bavdaz, Mojca

    2014-01-01

    Increasing reluctance of businesses to participate in surveys often leads to declining or low response rates, poor data quality and burden complaints, and suggests that a driving force, that is, the motivation for participation and accurate and timely response, is insufficient or lacking. Inspiratio

  14. In Search of Motivation for the Business Survey Response Task

    NARCIS (Netherlands)

    Torres van Grinsven, Vanessa; Bolko, Irena; Bavdaz, Mojca

    2014-01-01

    Increasing reluctance of businesses to participate in surveys often leads to declining or low response rates, poor data quality and burden complaints, and suggests that a driving force, that is, the motivation for participation and accurate and timely response, is insufficient or lacking.

  15. The WiggleZ Dark Energy Survey: constraining galaxy bias and cosmic growth with 3-point correlation functions

    CERN Document Server

    Marin, Felipe; Poole, Gregory; McBride, Cameron; Brough, Sarah; Colless, Matthew; Couch, Warrick; Croom, Scott; Croton, Darren; Davis, Tamara M; Drinkwater, Michael J; Forster, Karl; Gilbank, David; Gladders, Mike; Glazebrook, Karl; Jelliffe, Ben; Jurek, Russell J; Li, I-hui; Madore, Barry; Martin, D Christopher; Pimbblet, Kevin; Pracy, Michael; Sharp, Rob; Wisnioski, Emily; Woods, David; Wyder, Ted K; Yee, H K C

    2013-01-01

    Higher-order statistics are a useful and complementary tool for measuring the clustering of galaxies, containing information on the non-gaussian evolution and morphology of large-scale structure in the Universe. In this work we present measurements of the three-point correlation function (3PCF) for 187,000 galaxies in the WiggleZ spectroscopic galaxy survey. We explore the WiggleZ 3PCF scale and shape dependence at three different epochs z=0.35, 0.55 and 0.68, the highest redshifts where these measurements have been made to date. Using N-body simulations to predict the clustering of dark matter, we constrain the linear and non-linear bias parameters of WiggleZ galaxies with respect to dark matter, and marginalise over them to obtain constraints on sigma_8(z), the variance of perturbations on a scale of 8 Mpc/h and its evolution with redshift. These measurements of sigma_8(z), which have 10-20% accuracies, are consistent with the predictions of the LCDM concordance cosmology and test this model in a new way.

  16. Responses to catastrophic AGI risk: a survey

    Science.gov (United States)

    Sotala, Kaj; Yampolskiy, Roman V.

    2015-01-01

    Many researchers have argued that humanity will create artificial general intelligence (AGI) within the next twenty to one hundred years. It has been suggested that AGI may inflict serious damage to human well-being on a global scale (‘catastrophic risk’). After summarizing the arguments for why AGI may pose such a risk, we review the field's proposed responses to AGI risk. We consider societal proposals, proposals for external constraints on AGI behaviors and proposals for creating AGIs that are safe due to their internal design.

  17. Too Reliable to Be True? Response Bias as a Potential Source of Inflation in Paper-and-Pencil Questionnaire Reliability

    Directory of Open Access Journals (Sweden)

    Eyal Peer

    2011-06-01

    Full Text Available When respondents answer paper-and-pencil (PP questionnaires, they sometimes modify their responses to correspond to previously answered items. As a result, this response bias might artificially inflate the reliability of PP questionnaires. We compared the internal consistency of PP questionnaires to computerized questionnaires that presented a different number of items on a computer screen simultaneously. Study 1 showed that a PP questionnaire's internal consistency was higher than that of the same questionnaire presented on a computer screen with one, two or four questions per screen. Study 2 replicated these findings to show that internal consistency was also relatively high when all questions were shown on one screen. This suggests that the differences found in Study 1 were not due to the difference in presentation medium. Thus, this paper suggests that reliability measures of PP questionnaires might be inflated because of a response bias resulting from participants cross-checking their answers against ones given to previous questions.

  18. Picture Novelty Influences Response Selection and Inhibition: The Role of the In-Group Bias and Task-Difficulty

    Science.gov (United States)

    Zinchenko, Artyom; Mahmud, Waich; Alam, Musrura Mefta; Kabir, Nadia; Al-Amin, Md. Mamun

    2016-01-01

    The human visual system prioritizes processing of novel information, leading to faster detection of novel stimuli. Novelty facilitates conflict resolution through the enhanced early perceptual processing. However, the role of novel information processing during the conflict-related response selection and inhibition remains unclear. Here, we used a face-gender classification version of the Simon task and manipulated task-difficulty and novelty of task-relevant information. The novel quality of stimuli was made task-irrelevant, and an in-group bias was tightly controlled by manipulation of a gender of picture stimuli. We found that the in-group bias modulated the role of novelty in executive control. Novel opposite-sex stimuli facilitated response inhibition only when the task was not demanding. By contrast, novelty enhanced response selection irrespective of the in-group factor when task-difficulty was increased. These findings support the in-group bias mechanism of visual processing, in cases when attentional resources are not limited by a demanding task. The results are further discussed along the lines of the attentional load theory and neural mechanisms of response-inhibition and locomotor activity. In conclusion, our data showed that processing of novel information may enhance executive control through facilitated response selection and inhibition. PMID:27788213

  19. Evaluation of the Response Bias Scale and Improbable Failure Scale in assessing feigned cognitive impairment.

    Science.gov (United States)

    Grossi, Laura M; Green, Debbie; Einzig, Shanah; Belfi, Brian

    2017-05-01

    The present study evaluated the Response Bias scale (RBS), a symptom validity test embedded within the Minnesota Multiphasic Personality Inventory (MMPI)-2 Restructured Form (MMPI-2-RF) that assesses for feigned neurocognitive complaints, in a sample of pretrial incompetent to stand trial (IST) criminal defendants. Additionally, we examined the Improbable Failure (IF) scale, a performance validity test embedded within the Structured Interview of Reported Symptoms, Second Edition (SIRS-2), which similarly assesses for feigned cognitive impairment (FCI). Results indicated that both the RBS (area under the curve [AUC] = .76) and IF scale (AUC = .72) achieved moderate classification accuracy using the Test of Memory Malingering (TOMM) as the criterion. Further, the RBS and IF scale appeared to be most useful for screening out those defendants who presented as genuine (specificity = 99% and 88%, respectively), and less effective at classifying those defendants suspected of feigning according to the TOMM (sensitivity = 29% and 46%, respectively). In order to identify a significant proportion of IST defendants who may be feigning impairment, considerably lower cutoff scores than those recommended in each measure's manual were evaluated. An RBS T score of 63 (sensitivity = 86%; specificity = 37%), and IF scale raw score of 2 (sensitivity = 80%; specificity = 43%), was required to achieve ≥80% sensitivity; these alternate cutoff scores may therefore be useful when screening inpatient forensic psychiatric IST defendants. Further, the 2 scales effectively predicted TOMM classification in combination, although only the RBS significantly contributed to the model. Implications for the assessment of FCI in forensic psychiatric settings are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  20. Non-response in a survey among immigrants in Denmark

    DEFF Research Database (Denmark)

    Deding, Mette; Fridberg, Torben; Jakobsen, Vibeke

    The purpose of this paper is to study how various characteristics of respondents and interviewers affect non-response among immigrants. We use a survey conducted among immigrants in Denmark and ethnic Danes. First, we analyse the determinants of overall non-response. Second, we analyse how...... the determinants of contact and of response given contact differ. We find that characteristics of the respondents are important for the response rate – especially they are important for the probability of getting in contact with the respondent. The lower probability of response among immigrants compared to ethnic...

  1. Systemic dizocilpine (MK-801 facilitates performance in opposition to response bias

    Directory of Open Access Journals (Sweden)

    Lauwereyns Johan

    2007-09-01

    performance when reward is small. It is suggested that the facilitation may be due to the reinforcement of mechanisms that work in opposition to response bias. As a corollary, the study provides a useful paradigm to study the voluntary control of unavoidable action.

  2. In Search of Motivation for the Business Survey Response Task

    Directory of Open Access Journals (Sweden)

    Torres van Grinsven Vanessa

    2014-12-01

    Full Text Available Increasing reluctance of businesses to participate in surveys often leads to declining or low response rates, poor data quality and burden complaints, and suggests that a driving force, that is, the motivation for participation and accurate and timely response, is insufficient or lacking. Inspiration for ways to remedy this situation has already been sought in the psychological theory of self-determination; previous research has favored enhancement of intrinsic motivation compared to extrinsic motivation. Traditionally however, enhancing extrinsic motivation has been pervasive in business surveys. We therefore review this theory in the context of business surveys using empirical data from the Netherlands and Slovenia, and suggest that extrinsic motivation calls for at least as much attention as intrinsic motivation, that other sources of motivation may be relevant besides those stemming from the three fundamental psychological needs (competence, autonomy and relatedness, and that other approaches may have the potential to better explain some aspects of motivation in business surveys (e.g., implicit motives. We conclude with suggestions that survey organizations can consider when attempting to improve business survey response behavior.

  3. Human Bone Marrow Mesenchymal Stem Cells Regulate Biased DNA Segregation in Response to Cell Adhesion Asymmetry

    Directory of Open Access Journals (Sweden)

    Delphine Freida

    2013-11-01

    Full Text Available Biased DNA segregation is a mitotic event in which the chromatids carrying the original template DNA strands and those carrying the template copies are not segregated randomly into the two daughter cells. Biased segregation has been observed in several cell types, but not in human mesenchymal stem cells (hMSCs, and the factors affecting this bias have yet to be identified. Here, we have investigated cell adhesion geometries as a potential parameter by plating hMSCs from healthy donors on fibronectin-coated micropatterns. On symmetric micropatterns, the segregation of sister chromatids to the daughter cells appeared random. In contrast, on asymmetric micropatterns, the segregation was biased. This sensitivity to asymmetric extracellular cues was reproducible in cells from all donors but was not observed in human skin-derived fibroblasts or in a fibroblastic cell line used as controls. We conclude that the asymmetry of cell adhesion is a major factor in the regulation of biased DNA segregation in hMSCs.

  4. SAX-3 (Robo) and UNC-40 (DCC) regulate a directional bias for axon guidance in response to multiple extracellular cues.

    Science.gov (United States)

    Tang, Xia; Wadsworth, William G

    2014-01-01

    Axons in Caenorhabditis elegans are guided by multiple extracellular cues, including UNC-6 (netrin), EGL-20 (wnt), UNC-52 (perlecan), and SLT-1 (slit). How multiple extracellular cues determine the direction of axon guidance is not well understood. We have proposed that an axon's response to guidance cues can be modeled as a random walk, i.e., a succession of randomly directed movement. Guidance cues dictate the probability of axon outgrowth activity occurring in each direction, which over time creates a directional bias. Here we provide further evidence for this model. We describe the effects that the UNC-40 (DCC) and SAX-3 (Robo) receptors and the UNC-6, EGL-20, UNC-52, and SLT-1 extracellular cues have on the directional bias of the axon outgrowth activity for the HSN and AVM neurons. We find that the directional bias created by the cues depend on UNC-40 or SAX-3. UNC-6 and EGL-20 affect the directional bias for both neurons, whereas UNC-52 and SLT-1 only affect the directional bias for HSN and AVM, respectively. The direction of the bias created by the loss of a cue can vary and the direction depends on the other cues. The random walk model predicts this combinatorial regulation. In a random walk a probability is assigned for each direction of outgrowth, thus creating a probability distribution. The probability distribution for each neuron is determined by the collective effect of all the cues. Since the sum of the probabilities must equal one, each cue affects the probability of outgrowth in multiple directions.

  5. Corporate Social Responsibility in Engineering Education. A French Survey

    Science.gov (United States)

    Didier, C.; Huet, R.

    2008-01-01

    In this paper, we present and discuss the results of a survey of how corporate social responsibility (CSR) is being discussed and taught in engineering education in France. We shall first describe how those questions have been recently tackled in various programmes of higher education in France. We shall also analyse what faculty members have to…

  6. Response to ERIS 2014 States' Research Needs Survey

    Science.gov (United States)

    This document is ORD’s response to the states’ needs and priorities, as identified in the 2014 survey. ORD identified existing methods, models, tools and databases on these topics, as well as near-term research and development efforts, that could assist states in thei...

  7. The Department Head: A Survey of Duties and Responsibilities.

    Science.gov (United States)

    Papalia, Anthony

    This study surveys 107 foreign language departments in secondary schools in western New York and identifies duties and practices of those responsible for the departmental leadership. The report also determines the amount of released time granted to perform departmental duties. The educational preparation and work experience of supervisory staff…

  8. Corporate Social Responsibility in Engineering Education. A French Survey

    Science.gov (United States)

    Didier, C.; Huet, R.

    2008-01-01

    In this paper, we present and discuss the results of a survey of how corporate social responsibility (CSR) is being discussed and taught in engineering education in France. We shall first describe how those questions have been recently tackled in various programmes of higher education in France. We shall also analyse what faculty members have to…

  9. T cell Receptor Alpha Variable 12-2 bias in the immunodominant response to Yellow fever virus.

    Science.gov (United States)

    Bovay, Amandine; Zoete, Vincent; Dolton, Garry; Bulek, Anna M; Cole, David K; Rizkallah, Pierre J; Fuller, Anna; Beck, Konrad; Michielin, Olivier; Speiser, Daniel E; Sewell, Andrew K; Fuertes Marraco, Silvia A

    2017-10-03

    The repertoire of human αβ T cell receptors (TCRs) is generated via somatic recombination of germline gene segments. Despite this enormous variation, certain epitopes can be immunodominant, associated with high frequencies of antigen-specific T cells and/or exhibit bias towards a TCR gene segment. Here, we studied the TCR repertoire of the HLA-A*0201-restricted epitope LLWNGPMAV (hereafter, A2/LLW) from Yellow Fever virus, which generates an immunodominant CD8(+) T cell response to the highly effective YF-17D vaccine. We discover that these A2/LLW-specific CD8(+) T cells are highly biased for the TCR α chain TRAV12-2. This bias is already present in A2/LLW-specific naïve T cells before vaccination with YF-17D. Using CD8(+) T cell clones, we show that TRAV12-2 does not confer a functional advantage on a per cell basis. Molecular modeling indicated that the germline-encoded complementarity determining region (CDR) 1α loop of TRAV12-2 critically contributes to A2/LLW binding, in contrast to the conventional dominant dependence on somatically rearranged CDR3 loops. This germline component of antigen recognition may explain the unusually high precursor frequency, prevalence and immunodominance of T-cell responses specific for A2/LLW epitope. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  10. The Dark Triad and the PID-5 Maladaptive Personality Traits: Accuracy, Confidence and Response Bias in Judgments of Veracity

    Directory of Open Access Journals (Sweden)

    Benno G. Wissing

    2017-09-01

    Full Text Available The Dark Triad traits—narcissism, Machiavellianism and psychopathy—have been found to be associated with intra- or interpersonal deception production frequency. This cross-sectional study (N = 207 investigated if the Dark Triad traits are also associated with deception detection accuracy, as implicated by the recent conception of a deception-general ability. To investigate associations between maladaptive personality space and deception, the PID-5 maladaptive personality traits were included to investigate if besides Machiavellianism, Detachment is negatively associated with response bias. Finally, associations between the Dark Triad traits, Antagonism, Negative Affectivity and confidence judgments were investigated. Participants watched videos of lying vs. truth-telling senders and judged the truthfulness of the statements. None of the Dark Triad traits was found to be associated with the ability to detect deception. Detachment was negatively associated with response bias. Psychopathy was associated with global confidence judgments. The results provide additional support that dark and maladaptive personality traits are associated with judgmental biases but not with accuracy in deception detection. The internal consistencies of 4 of the 8 subscales of the used personality short scales were only low and nearly sufficient (αs =0.65–0.69.

  11. Emotion Evaluation and Response Slowing in a Non-Human Primate: New Directions for Cognitive Bias Measures of Animal Emotion?

    Directory of Open Access Journals (Sweden)

    Emily J. Bethell

    2016-01-01

    Full Text Available The cognitive bias model of animal welfare assessment is informed by studies with humans demonstrating that the interaction between emotion and cognition can be detected using laboratory tasks. A limitation of cognitive bias tasks is the amount of training required by animals prior to testing. A potential solution is to use biologically relevant stimuli that trigger innate emotional responses. Here; we develop a new method to assess emotion in rhesus macaques; informed by paradigms used with humans: emotional Stroop; visual cueing and; in particular; response slowing. In humans; performance on a simple cognitive task can become impaired when emotional distractor content is displayed. Importantly; responses become slower in anxious individuals in the presence of mild threat; a pattern not seen in non-anxious individuals; who are able to effectively process and disengage from the distractor. Here; we present a proof-of-concept study; demonstrating that rhesus macaques show slowing of responses in a simple touch-screen task when emotional content is introduced; but only when they had recently experienced a presumably stressful veterinary inspection. Our results indicate the presence of a subtle “cognitive freeze” response; the measurement of which may provide a means of identifying negative shifts in emotion in animals.

  12. Challenging the role of social norms regarding body weight as an explanation for weight, height, and BMI misreporting biases: Development and application of a new approach to examining misreporting and misclassification bias in surveys

    LENUS (Irish Health Repository)

    Brestoff, Jonathan R

    2011-05-18

    Abstract Background Cultural pressures to be thin and tall are postulated to cause people to misreport their body weight and height towards more socially normative (i.e., desirable) values, but a paucity of direct evidence supports this idea. We developed a novel non-linear approach to examining weight, height, and BMI misreporting biases and used this approach to examine the association between socially non-normative weight and misreporting biases in adults. Methods The Survey of Lifestyles, Attitudes, and Nutrition 2007 (SLÁN 2007), a nationally representative survey of the Republic of Ireland (N = 1942 analyzed) was used. Self-reported weight (height) was classified as under-reported by ≥2.0 kg (2.0 cm), over-reported by ≥2.0 kg (2.0 cm), or accurately reported within 2.0 kg (2.0 cm) to account for technical errors of measurement and short-term fluctuations in measured weight (height). A simulation strategy was used to define self-report-based BMI as under-estimated by more than 1.40 kg\\/m2, over-estimated by more than 1.40 kg\\/m2, or accurately estimated within 1.40 kg\\/m2. Patterns of biases in self-reported weight, height, and BMI were explored. Logistic regression was used to identify factors associated with mis-estimated BMI and to calculate adjusted odds ratios (AOR) and 99% confidence intervals (99%CI). Results The patterns of bias contributing the most to BMI mis-estimation were consistently, in decreasing order of influence, (1) under-reported weight combined with over-reported height, (2) under-reported weight with accurately reported height, and (3) accurately reported weight with over-reported height. Average bias in self-report-based BMI was -1.34 kg\\/m2 overall and -0.49, -1.33, and -2.66 kg\\/m2 in normal, overweight, and obese categories, respectively. Despite the increasing degree of bias with progressively higher BMI categories, persons describing themselves as too heavy were, within any given BMI category, less likely to have under

  13. Housing conditions affect rat responses to two types of ambiguity in a reward-reward discrimination cognitive bias task.

    Science.gov (United States)

    Parker, Richard M A; Paul, Elizabeth S; Burman, Oliver H P; Browne, William J; Mendl, Michael

    2014-11-01

    Decision-making under ambiguity in cognitive bias tasks is a promising new indicator of affective valence in animals. Rat studies support the hypothesis that animals in a negative affective state evaluate ambiguous cues negatively. Prior automated operant go/go judgement bias tasks have involved training rats that an auditory cue of one frequency predicts a Reward and a cue of a different frequency predicts a Punisher (RP task), and then measuring whether ambiguous cues of intermediate frequency are judged as predicting reward ('optimism') or punishment ('pessimism'). We investigated whether an automated Reward-Reward (RR) task yielded similar results to, and was faster to train than, RP tasks. We also introduced a new ambiguity test (simultaneous presentation of the two training cues) alongside the standard single ambiguous cue test. Half of the rats experienced an unpredictable housing treatment (UHT) designed to induce a negative state. Control rats were relatively 'pessimistic', whilst UHT rats were quicker, but no less accurate, in their responses in the RR test, and showed less anxiety-like behaviour in independent tests. A possible reason for these findings is that rats adapted to and were stimulated by UHT, whilst control rats in a predictable environment were more sensitive to novelty and change. Responses in the new ambiguity test correlated positively with those in single ambiguous cue tests, and may provide a measure of attention bias. The RR task was quicker to train than previous automated RP tasks. Together, they could be used to disentangle how reward and punishment processes underpin affect-induced cognitive biases.

  14. Comparison of two models of hemispheric specialization with unilaterally lesioned patients: material-specific impairment vs response-bias distortion.

    Science.gov (United States)

    Guimond, Anik; Braun, Claude M J; Daigneault, Sylvie; Farmer, Jean-Pierre

    2013-10-01

    Validity of two models of hemispheric specialization was compared. The "material-specific impairment" model was radicalized as postulating that left hemisphere (LH) lesions impair processing of verbal material and that right hemisphere (RH) lesions impair processing of visuospatial material, independently of response-bias distortions. The "response-bias distortion" model was radicalized as postulating that LH lesions distort response style toward omissiveness and that RH lesions distort response style toward commissiveness, regardless of material-specific impairments. Participants had comparable left (N=27) or right (N=24) hemisphere cortical lesions having occurred between birth and early adolescence. Four cognitive neuropsychological tests were adjusted to optimize applicability and comparability of the two theoretical models: Rey Complex Figure, Kimura's Recurring Figures, the Story Recall subtest of the Children's Memory Scale, and the California Verbal Learning Test. Both models significantly, independently, and equally distinguished the LH from the RH patients. Both these forms of hemispheric specialization seemed to be implemented very early in life and very rigidly. Intrahemispheric lesion sites, e.g., frontal vs nonfrontal, held no significant relation to the effects described above.

  15. Externalizing psychopathology and behavioral disinhibition: working memory mediates signal discriminability and reinforcement moderates response bias in approach-avoidance learning.

    Science.gov (United States)

    Endres, Michael J; Rickert, Martin E; Bogg, Tim; Lucas, Jesolyn; Finn, Peter R

    2011-05-01

    Research has suggested that reduced working memory capacity plays a key role in disinhibited patterns of behavior associated with externalizing psychopathology. In this study, participants (N = 365) completed 2 versions of a go/no-go mixed-incentive learning task that differed in the relative frequency of monetary rewards and punishments for correct and incorrect active-approach responses, respectively. Using separate structural equation models for conventional (hit and false alarm rates) and signal detection theory (signal discriminability and response bias) performance indices, distinct roles for working memory capacity and changes in payoff structure were found. Specifically, results showed that (a) working memory capacity mediated the effects of externalizing psychopathology on false alarms and discriminability of go versus no-go signals; (b) these effects were not moderated by the relative frequency of monetary rewards and punishments; (c) the relative frequency of monetary rewards and punishments moderated the effects of externalizing psychopathology on hits and response bias for go versus no-go responses; and (d) these effects were not mediated by working memory capacity. The findings implicate distinct roles for reduced working memory capacity and poorly modulated active approach and passive avoidance in the link between externalizing psychopathology and behavioral disinhibition.

  16. Respondents' recall of injury events: an investigation of recall bias in cross-sectional injury data from the Sudan Household Health Survey 2010.

    Science.gov (United States)

    Abdalla, Safa; Abdelgadir, Nahid; Shahraz, Saeid; Bhalla, Kavi

    2015-01-01

    Recall bias is a well-documented limitation of population-based cross-sectional injury surveys. To fill some gaps in this area, we investigated the extent and nature of recall bias in Sudan Household Health Survey (SHHS 2010) injury data. The extent of incomplete recall was measured by comparing the total reported injuries over 12 months with the annualised number of injuries in the four weeks preceding the survey. Multivariable logistic regression was used to investigate the association of socio-demographic variables, injury attributes and interviewee characteristics with differential recall. Relevant interactions were tested. Overall, reported injuries were 33% of the expected. Injuries among children 1-4 years had lower odds of being reported to have occurred earlier than the four weeks preceding the survey than people aged 65 years and over (OR = 0.24, 95% CI 0.12-0.47). Injuries that received inpatient care in the first week were more likely to be recalled than those that did not receive care (OR = 2.07, 95% CI 1.14-3.75). Respondent's age was associated with differential recall. Differential injury recall should be considered when using SHHS 2010 to compare injury occurrence between children under five and older groups or at the level of health care received.

  17. Non-Response in Student Surveys: The Role of Demographics, Engagement and Personality

    Science.gov (United States)

    Porter, Stephen R.; Whitcomb, Michael E.

    2005-01-01

    What causes a student to participate in a survey? This paper looks at participation across multiple surveys to understand survey non-response; by using multiple surveys we minimize the impact of survey salience. Students at a selective liberal arts college were administered four different surveys throughout the 2002-2003 academic year, and we use…

  18. Strouhal number dependency of the aero-acoustic response of wall perforations under combined grazing-bias flow

    Science.gov (United States)

    Moers, E. M. T.; Tonon, D.; Hirschberg, A.

    2017-02-01

    The influence of low Mach number grazing-bias flow on the linear acoustic response of slit shaped wall perforations is determined in terms of a dimensionless acoustical impedance for Strouhal numbers based on the perforation width of order unity. The influence of edge geometries is studied by experiments. In particular, slanted slits under an angle of 30° with respect to the grazing flow direction are considered. Sound production, i.e. whistling potentiality corresponding to a negative real part of the impedance, is observed for various geometries and flow conditions. Sound production restricts the largest perforation size which can be used in practice for acoustical liners. Whistling in the limit cases of purely bias and purely grazing flows can be explained qualitatively in terms of Vortex Sound Theory. For combined bias/grazing flow, most of the oscillations in the impedance as a function of the Strouhal number are related to these limit behaviours. A configuration with thin sharp edges both upstream and downstream corresponds to commonly used theoretical models assuming an infinite thin wall. This configuration displays a behaviour drastically different from a more realistic perforation geometry with sharp square edges.

  19. Is the web a promising tool for data collection in developing countries? An analysis of the sample bias of 10 web and face-to-face surveys from Africa, Asia, and South America

    NARCIS (Netherlands)

    Tijdens, K.; Steinmetz, S.

    2016-01-01

    Whereas the sample composition biases of web surveys have been discussed extensively for developed countries, studies for developing countries are scarce. This article helps to fill that gap by comparing similar non-probability-based web surveys (WEB) and probability-based face-to-face (F2F) surveys

  20. Constraints on Galaxy Bias, Omega_m, and Primordial Non-Gaussianity from the PSCz Survey Bispectrum

    CERN Document Server

    Feldman, H A; Fry, J N; Scoccimarro, R; Feldman, Hume A.; Frieman, Joshua A.

    2001-01-01

    We compute the bispectrum $B(k_1,k_2,k_3)$, the three-point correlation function in Fourier space, for the IRAS-PSCz galaxy catalog and show that it agrees well with gravitational instability predictions in a universe dominated by cold dark matter. Assuming a local bias model, we find linear and quadratic bias parameters $1/b_1=1.20^{+0.18}_{-0.19}$ and $b_2/b_1^2=-0.42^{+0.19}_{-0.19}$ for these galaxies. We find no sign of scale-dependent bias for wave-numbers $ k\\leq 0.3 \\kMpc$ and that Eulerian biasing is preferred over Lagrangian biasing. We also consider constraints from the bispectrum on non-Gaussian initial conditions. For a class of dimensional scaling models with $\\chi^2_N$ statistics (which become Gaussian as $N\\to\\infty$), we find that $N>49$. This implies that dimensional scaling models are constrained to have a primordial dimensionless skewness $B_3 < 0.35$.

  1. The positive feedback bias as a response to self-image threat.

    Science.gov (United States)

    Harber, Kent D; Stafford, Reshma; Kennedy, Kathleen A

    2010-03-01

    This research examined whether Whites favourably bias their feedback to minorities in order to see themselves as egalitarian. White teacher trainees first had their egalitarian self-images affirmed, left unchanged, or threatened. They then provided feedback on a poorly written essay supposedly authored by either a Black or a White student. As predicted, trainees in the Black writer/self-image threat condition selectively rated essay content more favourably, recommended less time for skill development, provided more favourable copy-editing comments, and generated more equivocating 'buffers'. In contrast, trainees in the Black writer/self-image boost condition supplied feedback indistinguishable from feedback provided by trainees in the White writer conditions, which was unaffected by the self-image conditions. The implications for minority education and intergroup communication are discussed.

  2. An Investigation of Certain Alleged Student Biases About Teacher Education at Western Kentucky University (Survey Number Three).

    Science.gov (United States)

    Laman, Archie E.; Reeves, Dorothy E.

    An opinionnaire was administered to 122 students in the teacher education program at Western Kentucky University as part of a longitudinal study to determine student attitudes toward their professors, courses, and themselves. Eight biases were tested: (1) Education courses tend to be easier than most other college courses; (2) Education courses…

  3. How Do Politicians Attribute Bureaucratic Responsibility for Performance? Negativity Bias and Interest Group Advocacy

    DEFF Research Database (Denmark)

    Nielsen, Poul A.; Moynihan, Donald P.

    2017-01-01

    of accountability, even as politicians are increasingly provided with performance data to hold bureaucrats accountable. We shed light on this issue using a survey experiment of elected officials featuring actual performance data. We find that the provision of performance data makes elected officials more willing...

  4. How Do Politicians Attribute Bureaucratic Responsibility for Performance? Negativity Bias and Interest Group Advocacy

    DEFF Research Database (Denmark)

    Nielsen, Poul A.; Moynihan, Donald P.

    2016-01-01

    of accountability, even as politicians are increasingly provided with performance data to hold bureaucrats accountable. We shed light on this issue using a survey experiment of elected officials featuring actual performance data. We find that the provision of performance data makes elected officials more willing...

  5. An investigation of the validity of the MMPI-2 response bias scale using an analog simulation design.

    Science.gov (United States)

    Sullivan, Karen A; Elliott, Cameron

    2012-01-01

    This study evaluated a measure of feigned cognitive symptoms, the MMPI-2 Response Bias Scale (RBS), using an analog simulation design. A total of 81 participants were randomly allocated to one of two conditions: simulation (n = 40) or control (n = 41). Simulators were instructed to feign memory impairment. All participants completed an abbreviated form of the MMPI-2, Warrington's Word Recognition Memory test, and the Test of Memory Malingering. MMPI-2 data were used to calculate the RBS, F, K. FBS scores were prorated. Significant group differences were found on all measures. The effect size of group differences was largest for the RBS (d = 2.52) compared to the prorated FBS (d = 2.11), F (d = 1.31), and K (d = 0.85). Despite strong significant correlations between MMPI-2 scores, the RBS added incrementally to the other validity indicators in the prediction of group membership. The results from this RBS simulation study are consistent with several previous known-groups evaluations, which suggest that this scale is a useful indicator of negative response bias associated with exaggerated memory impairment.

  6. Long-term changes in cognitive bias and coping response as a result of chronic unpredictable stress during adolescence

    Directory of Open Access Journals (Sweden)

    Lauren eChaby

    2013-07-01

    Full Text Available Animals that experience adverse events in early life often have life-long changes to their physiology and behavior. Long-term effects of stress during early life have been studied extensively, but less attention has been given to the consequences of negative experiences solely during the adolescent phase. Adolescence is a particularly sensitive period of life when regulation of the glucocorticoid stress hormone response matures and specific regions in the brain undergo considerable change. Aversive experiences during this time might, therefore, be expected to generate long-term consequences for the adult phenotype. Here we investigated the long-term effects of exposure to chronic unpredictable stress during adolescence on adult decision making, coping response, cognitive bias, and exploratory behavior in rats. Rats exposed to chronic unpredictable stress (e.g. isolation, crowding, cage tilt were compared to control animals that were maintained in standard, predictable conditions throughout development. Unpredictable stress during adolescence resulted in a suite of long-term behavioral and cognitive changes including a negative cognitive bias (F1,12 = 5.000, P < 0.05, altered coping response (T1,14 = 2.216, P = 0.04, and accelerated decision making (T1,14 = 3.245, P = 0.01. Exposure to chronic stress during adolescence also caused a short-term increase in boldness behaviors; in a novel object test 15 days after the last stressor, animals exposed to chronic unpredictable stress had decreased latencies to leave a familiar shelter and approach a novel object (T1,14 = 2.240, P = 0.04; T1,14 = 2.419, P = 0.03, respectively. The results showed that stress during adolescence has long-term impacts on behavior and cognition that affect the interpretation of ambiguous stimuli, behavioral response to adverse events, and how animals make decisions. Stress during adolescence also induced short-term changes in the way animals moved around a novel environment.

  7. Prenotification, Incentives, and Survey Modality: An Experimental Test of Methods to Increase Survey Response Rates of School Principals

    Science.gov (United States)

    Jacob, Robin Tepper; Jacob, Brian

    2012-01-01

    Teacher and principal surveys are among the most common data collection techniques employed in education research. Yet there is remarkably little research on survey methods in education, or about the most cost-effective way to raise response rates among teachers and principals. In an effort to explore various methods for increasing survey response…

  8. Prenotification, Incentives, and Survey Modality: An Experimental Test of Methods to Increase Survey Response Rates of School Principals

    Science.gov (United States)

    Jacob, Robin Tepper; Jacob, Brian

    2012-01-01

    Teacher and principal surveys are among the most common data collection techniques employed in education research. Yet there is remarkably little research on survey methods in education, or about the most cost-effective way to raise response rates among teachers and principals. In an effort to explore various methods for increasing survey response…

  9. Factors associated with survey response in hand surgery research.

    Science.gov (United States)

    Bot, Arjan G J; Anderson, Jade A; Neuhaus, Valentin; Ring, David

    2013-10-01

    A low response rate is believed to decrease the validity of survey studies. Factors associated with nonresponse to surveys are poorly characterized in orthopaedic research. This study addressed whether (1) psychologic factors; (2) demographics; (3) illness-related factors; and (4) pain are predictors of a lower likelihood of a patient returning a mailed survey. One hundred four adult, new or return patients completed questionnaires including the Pain Catastrophizing Scale, Patient Health Questionnaire-9 depression scale, Short Health Anxiety Index, demographics, and a pain scale (0-10) during a routine visit to a hand and upper extremity surgeon. Of these patients, 38% had undergone surgery and the remainder was seen for various other conditions. Six months after their visit, patients were mailed the DASH questionnaire and a scale to rate their satisfaction with the visit (0-10). Bivariate analysis and logistic regression were used to determine risk factors for being a nonresponder to the followup of this study. The cohort consisted of 57 women and 47 men with a mean age of 51 years with various diagnoses. Thirty-five patients (34%) returned the questionnaire. Responders were satisfied with their visit (mean satisfaction, 8.7) and had a DASH score of 9.6. Compared with patients who returned the questionnaires, nonresponders had higher pain catastrophizing scores, were younger, more frequently male, and had more pain at enrollment. In logistic regression, male sex (odds ratio [OR], 2.6), pain (OR, 1.3), and younger age (OR, 1.03) were associated with not returning the questionnaire. Survey studies should be interpreted in light of the fact that patients who do not return questionnaires in a hand surgery practice differ from patients who do return them. Hand surgery studies that rely on questionnaire evaluation remote from study enrollment should include tactics to improve the response of younger, male patients with more pain. Level II, prognostic study. See

  10. Reporting, handling and assessing the risk of bias associated with missing participant data in systematic reviews: a methodological survey.

    Science.gov (United States)

    Akl, Elie A; Carrasco-Labra, Alonso; Brignardello-Petersen, Romina; Neumann, Ignacio; Johnston, Bradley C; Sun, Xin; Briel, Matthias; Busse, Jason W; Ebrahim, Shanil; Granados, Carlos E; Iorio, Alfonso; Irfan, Affan; Martínez García, Laura; Mustafa, Reem A; Ramírez-Morera, Anggie; Selva, Anna; Solà, Ivan; Sanabria, Andrea Juliana; Tikkinen, Kari A O; Vandvik, Per O; Vernooij, Robin W M; Zazueta, Oscar E; Zhou, Qi; Guyatt, Gordon H; Alonso-Coello, Pablo

    2015-09-30

    To describe how systematic reviewers are reporting missing data for dichotomous outcomes, handling them in the analysis and assessing the risk of associated bias. We searched MEDLINE and the Cochrane Database of Systematic Reviews for systematic reviews of randomised trials published in 2010, and reporting a meta-analysis of a dichotomous outcome. We randomly selected 98 Cochrane and 104 non-Cochrane systematic reviews. Teams of 2 reviewers selected eligible studies and abstracted data independently and in duplicate using standardised, piloted forms with accompanying instructions. We conducted regression analyses to explore factors associated with using complete case analysis and with judging the risk of bias associated with missing participant data. Of Cochrane and non-Cochrane reviews, 47% and 7% (previews) and assuming no participants with missing data had the event (4%). The use of complete case analysis was associated only with Cochrane reviews (relative to non-Cochrane: OR=7.25; 95% CI 1.58 to 33.3, p=0.01). 65% of reviews assessed risk of bias associated with missing data; this was associated with Cochrane reviews (relative to non-Cochrane: OR=6.63; 95% CI 2.50 to 17.57, p=0.0001), and the use of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology (OR=5.02; 95% CI 1.02 to 24.75, p=0.047). Though Cochrane reviews are somewhat less problematic, most Cochrane and non-Cochrane systematic reviews fail to adequately report and handle missing data, potentially resulting in misleading judgements regarding risk of bias. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  11. 77 FR 20887 - Proposed Information Collection (National Acquisition Center Customer Response Survey) Activity...

    Science.gov (United States)

    2012-04-06

    ... solicits comments on the information needed to measure customer satisfaction with delivered products and... AFFAIRS Proposed Information Collection (National Acquisition Center Customer Response Survey) Activity...: Department of Veterans Affairs (VA) National Acquisition Center Customer Response Survey, VA Form 0863....

  12. On a problematic procedure to manipulate response biases in recognition experiments: the case of "implied" base rates.

    Science.gov (United States)

    Bröder, Arndt; Malejka, Simone

    2017-07-01

    The experimental manipulation of response biases in recognition-memory tests is an important means for testing recognition models and for estimating their parameters. The textbook manipulations for binary-response formats either vary the payoff scheme or the base rate of targets in the recognition test, with the latter being the more frequently applied procedure. However, some published studies reverted to implying different base rates by instruction rather than actually changing them. Aside from unnecessarily deceiving participants, this procedure may lead to cognitive conflicts that prompt response strategies unknown to the experimenter. To test our objection, implied base rates were compared to actual base rates in a recognition experiment followed by a post-experimental interview to assess participants' response strategies. The behavioural data show that recognition-memory performance was estimated to be lower in the implied base-rate condition. The interview data demonstrate that participants used various second-order response strategies that jeopardise the interpretability of the recognition data. We thus advice researchers against substituting actual base rates with implied base rates.

  13. Building the analytical response in frequency domain of AC biased bolometers. Application to Planck/HFI

    Science.gov (United States)

    Sauvé, Alexandre; Montier, Ludovic

    2016-12-01

    Context: Bolometers are high sensitivity detector commonly used in Infrared astronomy. The HFI instrument of the Planck satellite makes extensive use of them, but after the satellite launch two electronic related problems revealed critical. First an unexpected excess response of detectors at low optical excitation frequency for ν linearized versions of the bolometer electro thermal equilibrium. A custom description of signals in frequency is used to solve the problem with linear algebra. The model performances is validated using time domain simulations. Results: The provided expression is suitable for calibration and data processing. It can also be used to provide constraints for fitting optical transfer function using real data from steady state electronic response and optical response. The accurate description of electronic response can also be used to improve the ADC nonlinearity correction for quickly varying optical signals.

  14. Aniseikonia Tests: The Role of Viewing Mode, Response Bias, and Size–Color Illusions

    OpenAIRE

    García-Pérez, Miguel A.; Peli, Eli

    2015-01-01

    PURPOSE To identify the factors responsible for the poor validity of the most common aniseikonia tests, which involve size comparisons of red-green stimuli presented haploscopically. METHODS Aniseikonia was induced by afocal size lenses placed before one eye. Observers compared the sizes of semicircles presented haploscopically via color filters. The main factor under study was viewing mode (free viewing versus short presentations under central fixation). To eliminate response bia...

  15. Media Bias

    OpenAIRE

    Sendhil Mullainathan; Andrei Shleifer

    2002-01-01

    There are two different types of media bias. One bias, which we refer to as ideology, reflects a news outlet's desire to affect reader opinions in a particular direction. The second bias, which we refer to as spin, reflects the outlet's attempt to simply create a memorable story. We examine competition among media outlets in the presence of these biases. Whereas competition can eliminate the effect of ideological bias, it actually exaggerates the incentive to spin stories.

  16. The 'male escape hypothesis': sex-biased metamorphosis in response to climatic drivers in a facultatively paedomorphic amphibian.

    Science.gov (United States)

    Mathiron, Anthony G E; Lena, Jean-Paul; Baouch, Sarah; Denoël, Mathieu

    2017-04-26

    Paedomorphosis is a major evolutionary process that bypasses metamorphosis and allows reproduction in larvae. In newts and salamanders, it can be facultative with paedomorphs retaining gills and metamorphs dispersing. The evolution of these developmental processes is thought to have been driven by the costs and benefits of inhabiting aquatic versus terrestrial habitats. In this context, we aimed at testing the hypothesis that climatic drivers affect phenotypic transition and the difference across sexes because sex-ratio is biased in natural populations. Through a replicated laboratory experiment, we showed that paedomorphic palmate newts (Lissotriton helveticus) metamorphosed at a higher frequency when water availability decreased and metamorphosed earlier when temperature increased in these conditions. All responses were sex-biased, and males were more prone to change phenotype than females. Our work shows how climatic variables can affect facultative paedomorphosis and support theoretical models predicting life on land instead of in water. Moreover, because males metamorphose and leave water more often and earlier than females, these results, for the first time, give an experimental explanation for the rarity of male paedomorphosis (the 'male escape hypothesis') and suggest the importance of sex in the evolution of paedomorphosis versus metamorphosis. © 2017 The Author(s).

  17. A General Factor-Analytic Procedure for Assessing Response Bias in Questionnaire Measures

    Science.gov (United States)

    Ferrando, Pere J.; Lorenzo-Seva, Urbano; Chico, Eliseo

    2009-01-01

    This article proposes procedures for simultaneously assessing and controlling acquiescence and social desirability in questionnaire items. The procedures are based on a semi-restricted factor-analytic tridimensional model, and can be used with binary, graded-response, or more continuous items. We discuss procedures for fitting the model (item…

  18. Building the analytical response in frequency domain of AC biased bolometers Application to Planck/HFI

    CERN Document Server

    Sauvé, Alexandre

    2016-01-01

    Context: Bolometers are high sensitivity detector commonly used in Infrared astronomy. The HFI instrument of the Planck satellite makes extensive use of them, but after the satellite launch two electronic related problems revealed critical. First an unexpected excess response of detectors at low optical excitation frequency for {\

  19. Field measurements give biased estimates of functional response parameters, but help explain foraging distributions

    NARCIS (Netherlands)

    Duijns, S.; Knot, I.E.; Piersma, T.; van Gils, J.A.

    2015-01-01

    1.Mechanistic insights and predictive understanding of the spatial distributions of foragers are typically derived by fitting either field measurements on intake rates and food abundance, or observations from controlled experiments, to functional response models. It has remained unclear, however, wh

  20. Observers' reactions to genetic testing: the role of hindsight bias and judgements of responsibility.

    Science.gov (United States)

    Menec, V H; Weiner, B

    2000-08-01

    In 3 studies, we examined the effect of birth outcome on observers' reactions to genetic testing. Participants read a scenario in which a woman declined to take a genetic screening test and subsequently gave birth to a child with a genetic disorder (negative outcome) or a healthy child (positive outcome). Retrospective judgments of the likelihood that the child would have a genetic disorder were higher given negative than positive outcome knowledge under conditions of high genetic risk. Moreover, the more likely a negative outcome was perceived to be, the more responsible the mother was held for not taking the genetic screening test. Consistent with Weiner's (1993) theory, responsibility judgments were linked to displeasure and sympathy, with sympathy in turn being related to help judgments.

  1. Striatal intrinsic reinforcement signals during recognition memory: relationship to response bias and dysregulation in schizophrenia

    OpenAIRE

    Wolf, Daniel H.; Gerraty, Raphael T.; Satterthwaite, Theodore D.; James eLoughead; Timothy eCampellone; Elliott, Mark A.; Turetsky, Bruce I.; Gur, Ruben C.; Gur, Raquel E.

    2011-01-01

    Ventral striatum (VS) is a critical brain region for reinforcement learning and motivation, and VS hypofunction is implicated in psychiatric disorders including schizophrenia. Providing rewards or performance feedback has been shown to activate VS. Intrinisically motivated subjects performing challenging cognitive tasks are likely to engage reinforcement circuitry even in the absence of external feedback or incentives. However, such intrinsic reinforcement responses have received little atte...

  2. A single subset of dendritic cells controls the cytokine bias of natural killer T cell responses to diverse glycolipid antigens.

    Science.gov (United States)

    Arora, Pooja; Baena, Andres; Yu, Karl O A; Saini, Neeraj K; Kharkwal, Shalu S; Goldberg, Michael F; Kunnath-Velayudhan, Shajo; Carreño, Leandro J; Venkataswamy, Manjunatha M; Kim, John; Lazar-Molnar, Eszter; Lauvau, Gregoire; Chang, Young-tae; Liu, Zheng; Bittman, Robert; Al-Shamkhani, Aymen; Cox, Liam R; Jervis, Peter J; Veerapen, Natacha; Besra, Gurdyal S; Porcelli, Steven A

    2014-01-16

    Many hematopoietic cell types express CD1d and are capable of presenting glycolipid antigens to invariant natural killer T cells (iNKT cells). However, the question of which cells are the principal presenters of glycolipid antigens in vivo remains controversial, and it has been suggested that this might vary depending on the structure of a particular glycolipid antigen. Here we have shown that a single type of cell, the CD8α(+) DEC-205(+) dendritic cell, was mainly responsible for capturing and presenting a variety of different glycolipid antigens, including multiple forms of α-galactosylceramide that stimulate widely divergent cytokine responses. After glycolipid presentation, these dendritic cells rapidly altered their expression of various costimulatory and coinhibitory molecules in a manner that was dependent on the structure of the antigen. These findings show flexibility in the outcome of two-way communication between CD8α(+) dendritic cells and iNKT cells, providing a mechanism for biasing toward either proinflammatory or anti-inflammatory responses.

  3. A Single Subset of Dendritic Cells Controls the Cytokine Bias of Natural Killer T Cell Responses to Diverse Glycolipid Antigens

    Science.gov (United States)

    Arora, Pooja; Baena, Andres; Yu, Karl O.A.; Saini, Neeraj K.; Kharkwal, Shalu S.; Goldberg, Michael F.; Kunnath-Velayudhan, Shajo; Carreño, Leandro J.; Venkataswamy, Manjunatha M.; Kim, John; Lazar-Molnar, Eszter; Lauvau, Gregoire; Chang, Young-tae; Liu, Zheng; Bittman, Robert; Al-Shamkhani, Aymen; Cox, Liam R.; Jervis, Peter J.; Veerapen, Natacha; Besra, Gurdyal S.; Porcelli, Steven A.

    2014-01-01

    Summary Many hematopoietic cell types express CD1d and are capable of presenting glycolipid antigens to invariant natural killer T cells (iNKT cells). However, the question of which cells are the principal presenters of glycolipid antigens in vivo remains controversial, and it has been suggested that this might vary depending on the structure of a particular glycolipid antigen. Here we have shown that a single type of cell, the CD8α+ DEC-205+ dendritic cell, was mainly responsible for capturing and presenting a variety of different glycolipid antigens, including multiple forms of α-galactosylceramide that stimulate widely divergent cytokine responses. After glycolipid presentation, these dendritic cells rapidly altered their expression of various costimulatory and coinhibitory molecules in a manner that was dependent on the structure of the antigen. These findings show flexibility in the outcome of two-way communication between CD8α+ dendritic cells and iNKT cells, providing a mechanism for biasing toward either proinflammatory or anti-inflammatory responses. PMID:24412610

  4. Stigma in Canada: Results From a Rapid Response Survey

    Science.gov (United States)

    Stuart, Heather; Patten, Scott B; Koller, Michelle; Modgill, Geeta; Liinamaa, Tiina

    2014-01-01

    Objective: Our paper presents findings from the first population survey of stigma in Canada using a new measure of stigma. Empirical objectives are to provide a descriptive profile of Canadian’s expectations that people will devalue and discriminate against someone with depression, and to explore the relation between experiences of being stigmatized in the year prior to the survey among people having been treated for a mental illness with a selected number of sociodemographic and mental health–related variables. Method: Data were collected by Statistics Canada using a rapid response format on a representative sample of Canadians (n = 10 389) during May and June of 2010. Public expectations of stigma and personal experiences of stigma in the subgroup receiving treatment for a mental illness were measured. Results: Over one-half of the sample endorsed 1 or more of the devaluation discrimination items, indicating that they believed Canadians would stigmatize someone with depression. The item most frequently endorsed concerned employers not considering an application from someone who has had depression. Over one-third of people who had received treatment in the year prior to the survey reported discrimination in 1 or more life domains. Experiences of discrimination were strongly associated with perceptions that Canadians would devalue someone with depression, younger age (12 to 15 years), and self-reported poor general mental health. Conclusions: The Mental Health Experiences Module reflects an important partnership between 2 national organizations that will help Canada fulfill its monitoring obligations under the United Nations Convention on the Rights of Persons with Disabilities and provide a legacy to researchers and policy-makers who are interested in monitoring changes in stigma over time. PMID:25565699

  5. Surveys: an introduction.

    Science.gov (United States)

    Rubenfeld, Gordon D

    2004-10-01

    Surveys are a valuable research tool for studying the knowledge, attitudes, and behavior of a study population. This article explores quantitative analyses of written questionnaires as instruments for survey research. Obtaining accurate and precise information from a survey requires minimizing the possibility of bias from inappropriate sampling or a flawed survey instrument, and this article describes strategies to minimize sampling bias by increasing response rates, comparing responders to nonresponders, and identifying the appropriate sampling population. It is crucial that the survey instrument be valid, meaning that it actually measures what the investigator intends it to measure. In developing a valid survey instrument, it can be useful to adapt survey instruments that were developed by other researchers and to conduct extensive pilot-testing of your survey instrument.

  6. Familiarity bias and physiological responses in contagious yawning by dogs support link to empathy.

    Directory of Open Access Journals (Sweden)

    Teresa Romero

    Full Text Available In humans, the susceptibility to yawn contagion has been theoretically and empirically related to our capacity for empathy. Because of its relevance to evolutionary biology, this phenomenon has been the focus of recent investigations in non-human species. In line with the empathic hypothesis, contagious yawning has been shown to correlate with the level of social attachment in several primate species. Domestic dogs (Canis familiaris have also shown the ability to yawn contagiously. To date, however, the social modulation of dog contagious yawning has received contradictory support and alternative explanations (i.e., yawn as a mild distress response could explain positive evidence. The present study aims to replicate contagious yawning in dogs and to discriminate between the two possible mediating mechanisms (i.e., empathic vs. distress related response. Twenty-five dogs observed familiar (dog's owner and unfamiliar human models (experimenter acting out a yawn or control mouth movements. Concurrent physiological measures (heart rate were additionally monitored for twenty-one of the subjects. The occurrence of yawn contagion was significantly higher during the yawning condition than during the control mouth movements. Furthermore, the dogs yawned more frequently when watching the familiar model than the unfamiliar one demonstrating that the contagiousness of yawning in dogs correlated with the level of emotional proximity. Moreover, subjects' heart rate did not differ among conditions suggesting that the phenomenon of contagious yawning in dogs is unrelated to stressful events. Our findings are consistent with the view that contagious yawning is modulated by affective components of the behavior and may indicate that rudimentary forms of empathy could be present in domesticated dogs.

  7. A middle class image of society : A study of undercoverage and nonresponse bias in a telephone survey

    NARCIS (Netherlands)

    van Goor, Henk; Rispens, S

    2004-01-01

    We studied undercoverage and nonresponse in a telephone survey among the population of the City of Groningen, the Netherlands. The original sample, drawn from the municipal population register, contained 7000 individuals. For 37 percent of them, the telephone company was unable to produce a valid te

  8. Bias in research.

    Science.gov (United States)

    Simundić, Ana-Maria

    2013-01-01

    By writing scientific articles we communicate science among colleagues and peers. By doing this, it is our responsibility to adhere to some basic principles like transparency and accuracy. Authors, journal editors and reviewers need to be concerned about the quality of the work submitted for publication and ensure that only studies which have been designed, conducted and reported in a transparent way, honestly and without any deviation from the truth get to be published. Any such trend or deviation from the truth in data collection, analysis, interpretation and publication is called bias. Bias in research can occur either intentionally or unintentionally. Bias causes false conclusions and is potentially misleading. Therefore, it is immoral and unethical to conduct biased research. Every scientist should thus be aware of all potential sources of bias and undertake all possible actions to reduce or minimize the deviation from the truth. This article describes some basic issues related to bias in research.

  9. The ESO Slice Project (ESP) galaxy redshift survey. IV. A discussion of systematic biases in galaxy redshift determinations

    Science.gov (United States)

    Cappi, A.; Zamorani, G.; Zucca, E.; Vettolani, G.; Merighi, R.; Mignoli, M.; Stirpe, G. M.; Collins, C.; Guzzo, L.; Chincarini, G.; Maccagni, D.; Balkowski, C.; Cayatte, V.; Maurogordato, S.; Proust, D.; Bardelli, S.; Ramella, M.; Scaramella, R.; Blanchard, A.; MacGillivray, H.

    1998-08-01

    We present a detailed discussion of the redshift errors associated to the ESO Slice Project measurements. For a subsample of 742 galaxies with redshifts determined both from the absorption lines (Vabs) and from the emission lines (Vemi), we find an average difference Vabs - Vemi> =~ +100 km/s. We find that a similar effect is present in another, deeper redshift survey, the Durham/Anglo-Australian Telescope faint galaxy redshift survey (Broadhurst et al. 1988), while is absent in surveys at brighter magnitude limits. We have investigated in detail many possible sources of such a discrepancy, and we can exclude possible zero-point shifts or calibration problems. We have detected and measured systematic velocity differences produced by the different templates used in the cross-correlation. We conclude that such differences can in principle explain the effect, but in this case the non-trivial implication would be that the best-fitting template does not necessarily give the best velocity estimate. As we do not have any a priori reason to select a template different from the best-fitting one, we did not apply any correction to the ESO Slice Project velocities. However, as for a small number of galaxies the effect is so large that it is likely to have a physical explanation, we have also taken into account the possibility that the discrepancy can be partly real: in this case, it might help to understand the role of gas outflows in the process of galaxy evolution. In view of the future large spectroscopic surveys, we stress the importance of using different templates and making them publicly available, in order to assess the amplitude of systematic effects, and to allow a direct comparison of different catalogues. based on observations collected at the European Southern Observatory, La Silla, Chile.

  10. On the Cluster Physics of Sunyaev-Zel'dovich and X-ray Surveys III: Measurement Biases and Cosmological Evolution of Gas and Stellar Mass Fractions

    CERN Document Server

    Battaglia, N; Pfrommer, C; Sievers, J L

    2012-01-01

    Gas masses tightly correlate with the virial masses of galaxy clusters, allowing for a precise determination of cosmological parameters by means of large-scale X-ray surveys. However, according to recent Suzaku X-ray measurements, gas mass fractions, f_gas, appear to be considerably larger than the cosmic mean at the virial radius, R_200, questioning the accuracy of the cosmological parameter estimations. Here, we use a large suite of cosmological hydrodynamical simulations to study measurement biases of f_gas. We employ different variants of simulated physics, including radiative gas physics, star formation, and thermal feedback by active galactic nuclei. Computing the mass profiles in 48 angular cones, whose footprints partition the sphere, we find anisotropic gas and total mass distributions that imply an angular variance of f_gas at the level of 30%. This anisotropic distribution originates from the recent formation epoch of clusters and from the strong internal baryon-to-dark-matter density bias. In the ...

  11. Galaxies in the Illustris simulation as seen by the Sloan Digital Sky Survey - I: Bulge+disc decompositions, methods, and biases.

    Science.gov (United States)

    Bottrell, Connor; Torrey, Paul; Simard, Luc; Ellison, Sara L.

    2017-05-01

    We present an image-based method for comparing the structural properties of galaxies produced in hydrodynamical simulations to real galaxies in the Sloan Digital Sky Survey. The key feature of our work is the introduction of extensive observational realism, such as object crowding, noise and viewing angle, to the synthetic images of simulated galaxies, so that they can be fairly compared to real galaxy catalogues. We apply our methodology to the dust-free synthetic image catalogue of galaxies from the Illustris simulation at z = 0, which are then fit with bulge+disc models to obtain morphological parameters. In this first paper in a series, we detail our methods, quantify observational biases and present publicly available bulge+disc decomposition catalogues. We find that our bulge+disc decompositions are largely robust to the observational biases that affect decompositions of real galaxies. However, we identify a significant population of galaxies (roughly 30 per cent of the full sample) in Illustris that are prone to internal segmentation, leading to systematically reduced flux estimates by up to a factor of 6, smaller half-light radii by up to a factor of ˜2 and generally erroneous bulge-to-total fractions of (B/T) = 0.

  12. Galaxies in the Illustris simulation as seen by the Sloan Digital Sky Survey - I: Bulge+disc decompositions, methods, and biases.

    Science.gov (United States)

    Bottrell, Connor; Torrey, Paul; Simard, Luc; Ellison, Sara L.

    2017-01-01

    We present an image-based method for comparing the structural properties of galaxies produced in hydrodynamical simulations to real galaxies in the Sloan Digital Sky Survey. The key feature of our work is the introduction of extensive observational realism, such as object crowding, noise and viewing angle, to the synthetic images of simulated galaxies, so that they can be fairly compared to real galaxy catalogs. We apply our methodology to the dust-free synthetic image catalog of galaxies from the Illustris simulation at z = 0, which are then fit with bulge+disc models to obtain morphological parameters. In this first paper in a series, we detail our methods, quantify observational biases, and present publicly available bulge+disc decomposition catalogs. We find that our bulge+disc decompositions are largely robust to the observational biases that affect decompositions of real galaxies. However, we identify a significant population of galaxies (roughly 30% of the full sample) in Illustris that are prone to internal segmentation, leading to systematically reduced flux estimates by up to a factor of 6, smaller half-light radii by up to a factor of ˜ 2, and generally erroneous bulge-to-total fractions of (B/T)=0.

  13. Intergroup bias.

    Science.gov (United States)

    Hewstone, Miles; Rubin, Mark; Willis, Hazel

    2002-01-01

    This chapter reviews the extensive literature on bias in favor of in-groups at the expense of out-groups. We focus on five issues and identify areas for future research: (a) measurement and conceptual issues (especially in-group favoritism vs. out-group derogation, and explicit vs. implicit measures of bias); (b) modern theories of bias highlighting motivational explanations (social identity, optimal distinctiveness, uncertainty reduction, social dominance, terror management); (c) key moderators of bias, especially those that exacerbate bias (identification, group size, status and power, threat, positive-negative asymmetry, personality and individual differences); (d) reduction of bias (individual vs. intergroup approaches, especially models of social categorization); and (e) the link between intergroup bias and more corrosive forms of social hostility.

  14. Several common biases and control measures during sampling survey of eye diseases in China%我国眼病抽样调查中的常见偏倚问题与对策

    Institute of Scientific and Technical Information of China (English)

    管怀进

    2008-01-01

    Bias is a common artificial error during sampling survey in eye diseases, and is a major impact factor for validity and reliability of the survey. The causes and the control measures of several biases regarding current sampling survey of eye diseases in China were analyzed and discussed, including the sampling bias, non-respondent bias, and diagnostic bias. This review emphasizes that controlling bias is the key to ensure quality of sampling survey. Random sampling, sufficient sample quantity, careful examination and taking history, improving examination rate, accurate diagnosis, strict training and preliminary study, aswell as quality control can eliminate or minimize biases and improve the sampling survey quality of eye diseases in China.%偏倚是眼病抽样调查中常见的人为误差,是影响调查结果真实性与可靠性的主要原因.本文分析评论了我国眼病抽样调查中常见的几种偏倚,包括抽样偏倚、无应答偏倚及诊断偏倚等的产生原因及其对策;强调控制偏倚足确保调查研究质虽的关键;指出只要随机化抽样、样本量足够、认真检录和询问病史、提高受检率、准确检查诊断、严格培训及预试验,并做好质量控制工作,就可以将偏倚消除或减少到最低程度,从而提高我国眼病抽样调查质量.

  15. Bias of health estimates obtained from chronic disease and risk factor surveillance systems using telephone population surveys in Australia: results from a representative face-to-face survey in Australia from 2010 to 2013

    Directory of Open Access Journals (Sweden)

    Eleonora Dal Grande

    2016-04-01

    Full Text Available Abstract Background Emerging communication technologies have had an impact on population-based telephone surveys worldwide. Our objective was to examine the potential biases of health estimates in South Australia, a state of Australia, obtained via current landline telephone survey methodologies and to report on the impact of mobile-only household on household surveys. Methods Data from an annual multi-stage, systematic, clustered area, face-to-face population survey, Health Omnibus Survey (approximately 3000 interviews annually, included questions about telephone ownership to assess the population that were non-contactable by current telephone sampling methods (2006 to 2013. Univariable analyses (2010 to 2013 and trend analyses were conducted for sociodemographic and health indicator variables in relation to telephone status. Relative coverage biases (RCB of two hypothetical telephone samples was undertaken by examining the prevalence estimates of health status and health risk behaviours (2010 to 2013: directory-listed numbers, consisting mainly of landline telephone numbers and a small proportion of mobile telephone numbers; and a random digit dialling (RDD sample of landline telephone numbers which excludes mobile-only households. Results Telephone (landline and mobile coverage in South Australia is very high (97 %. Mobile telephone ownership increased slightly (7.4 %, rising from 89.7 % in 2006 to 96.3 % in 2013; mobile-only households increased by 431 % over the eight year period from 5.2 % in 2006 to 27.6 % in 2013. Only half of the households have either a mobile or landline number listed in the telephone directory. There were small differences in the prevalence estimates for current asthma, arthritis, diabetes and obesity between the hypothetical telephone samples and the overall sample. However, prevalence estimate for diabetes was slightly underestimated (RCB value of −0.077 in 2013. Mixed RCB results were found for having a

  16. The WiggleZ Dark Energy Survey: constraining galaxy bias and cosmic growth with 3-point correlation functions

    OpenAIRE

    Marin, Felipe; Blake, Chris; Poole, Gregory; McBride, Cameron; Brough, Sarah; Colless, Matthew; Couch, Warrick; Croom, Scott; Croton, Darren; Davis, Tamara M.; Drinkwater, Michael J.; Forster, Karl; Gilbank, David; Gladders, Mike; Glazebrook, Karl

    2013-01-01

    Higher-order statistics are a useful and complementary tool for measuring the clustering of galaxies, containing information on the non-gaussian evolution and morphology of large-scale structure in the Universe. In this work we present measurements of the three-point correlation function (3PCF) for 187,000 galaxies in the WiggleZ spectroscopic galaxy survey. We explore the WiggleZ 3PCF scale and shape dependence at three different epochs z=0.35, 0.55 and 0.68, the highest redshifts where thes...

  17. FILTER-INDUCED BIAS IN Lyα EMITTER SURVEYS: A COMPARISON BETWEEN STANDARD AND TUNABLE FILTERS. GRAN TELESCOPIO CANARIAS PRELIMINARY RESULTS

    Energy Technology Data Exchange (ETDEWEB)

    De Diego, J. A.; De Leo, M. A. [Instituto de Astronomía, Universidad Nacional Autónoma de México Avenida Universidad 3000, Ciudad Universitaria, C.P. 04510, Distrito Federal (Mexico); Cepa, J.; Bongiovanni, A. [Instituto de Astrofísica de Canarias, E-38205 La Laguna, Tenerife (Spain); Verdugo, T. [Centro de Investigaciones de Astronomía (CIDA), Apartado Postal 264, Mérida 5101-A (Venezuela, Bolivarian Republic of); Sánchez-Portal, M. [Herschel Science Centre (HSC), European Space Agency Centre (ESAC)/INSA, Villanueva de la Cañada, Madrid (Spain); González-Serrano, J. I., E-mail: jdo@astro.unam.mx [Instituto de Física de Cantabria (CSIC-Universidad de Cantabria), E-39005 Santander (Spain)

    2013-10-01

    Lyα emitter (LAE) surveys have successfully used the excess in a narrowband filter compared to a nearby broadband image to find candidates. However, the odd spectral energy distribution (SED) of LAEs combined with the instrumental profile has important effects on the properties of the candidate samples extracted from these surveys. We investigate the effect of the bandpass width and the transmission profile of the narrowband filters used for extracting LAE candidates at redshifts z ≅ 6.5 through Monte Carlo simulations, and we present pilot observations to test the performance of tunable filters to find LAEs and other emission-line candidates. We compare the samples obtained using a narrow ideal rectangular filter, the Subaru NB921 narrowband filter, and sweeping across a wavelength range using the ultra-narrow-band tunable filters of the instrument OSIRIS, installed at the 10.4 m Gran Telescopio Canarias. We use this instrument for extracting LAE candidates from a small set of real observations. Broadband data from the Subaru, Hubble Space Telescope, and Spitzer databases were used for fitting SEDs to calculate photometric redshifts and to identify interlopers. Narrowband surveys are very efficient in finding LAEs in large sky areas, but the samples obtained are not evenly distributed in redshift along the filter bandpass, and the number of LAEs with equivalent widths <60 Å can be underestimated. These biased results do not appear in samples obtained using ultra-narrow-band tunable filters. However, the field size of tunable filters is restricted because of the variation of the effective wavelength across the image. Thus, narrowband and ultra-narrow-band surveys are complementary strategies to investigate high-redshift LAEs.

  18. The Munich Near-Infrared Cluster Survey -- IV. Biases in the Completeness of Near-Infrared Imaging Data

    CERN Document Server

    Snigula, J; Bender, R; Botzler, C S; Feulner, G; Hopp, U

    2002-01-01

    We present the results of completeness simulations for the detection of point sources as well as redshifted elliptical and spiral galaxies in the K'-band images of the Munich Near-Infrared Cluster Survey (MUNICS). The main focus of this work is to quantify the selection effects introduced by threshold-based object detection algorithms used in deep imaging surveys. Therefore, we simulate objects obeying the well-known scaling relations between effective radius and central surface brightness, both for de Vaucouleurs and exponential profiles. The results of these simulations, while presented for the MUNICS project, are applicable in a much wider context to deep optical and near-infrared selected samples. We investigate the detection probability as well as the reliability for recovering the true total magnitude with Kron-like (adaptive) aperture photometry. The results are compared to the predictions of the visibility theory of Disney and Phillipps in terms of the detection rate and the lost-light fraction. Addit...

  19. How Important Are High Response Rates for College Surveys?

    Science.gov (United States)

    Fosnacht, Kevin; Sarraf, Shimon; Howe, Elijah; Peck, Leah K.

    2017-01-01

    Surveys play an important role in understanding the higher education landscape. About 60 percent of the published research in major higher education journals utilized survey data (Pike, 2007). Institutions also commonly use surveys to assess student outcomes and evaluate programs, instructors, and even cafeteria food. However, declining survey…

  20. How Important Are High Response Rates for College Surveys?

    Science.gov (United States)

    Fosnacht, Kevin; Sarraf, Shimon; Howe, Elijah; Peck, Leah K.

    2017-01-01

    Surveys play an important role in understanding the higher education landscape. About 60 percent of the published research in major higher education journals utilized survey data (Pike, 2007). Institutions also commonly use surveys to assess student outcomes and evaluate programs, instructors, and even cafeteria food. However, declining survey…

  1. Test of item-response bias in the CES-D scale. experience from the New Haven EPESE study.

    Science.gov (United States)

    Cole, S R; Kawachi, I; Maller, S J; Berkman, L F

    2000-03-01

    We present results of item-response bias analyses of the exogenous variables age, gender, and race for all items from the Center for Epidemiologic Studies Depression (CES-D) scale using data (N = 2340) from the New Haven component of the Established Populations for Epidemiologic Studies of the Elderly (EPESE). The proportional odds of blacks responding higher on the CES-D items "people are unfriendly" and "people dislike me" were 2.29 (95% confidence interval: 1.74, 3.02) and 2.96 (95% confidence interval: 2.15, 4.07) times that of whites matched on overall depressive symptoms, respectively. In addition, the proportional odds of women responding higher on the CES-D item "crying spells" were 2.14 (95% confidence interval: 1.60, 2.82) times that of men matched on overall depressive symptoms. Our data indicate the CES-D would have greater validity among this diverse group of older men and women after removal of the crying item and two interpersonal items.

  2. Self-esteem modulates dorsal medial prefrontal cortical response to self-positivity bias in implicit self-relevant processing.

    Science.gov (United States)

    Yang, Juan; Dedovic, Katarina; Guan, Lili; Chen, Yu; Qi, Mingming

    2014-11-01

    Processing self-related material recruits similar neural networks regardless of whether the self-relevance is made explicit or not. However, when considering the neural mechanisms that distinctly underlie cognitive and affective components of self-reflection, it is still unclear whether the same mechanisms are involved when self-reflection is explicit or implicit, and how these mechanisms may be modulated by individual personality traits, such as self-esteem. In the present functional MRI study, 25 participants were exposed to positive and negative words that varied with respect to the degree of self-relevance for each participant; however, the participants were asked to make a judgment about the color of the words. Regions-of-interest analysis showed that medial prefrontal cortex (mPFC) and posterior cingulate cortex were associated with gauging the self-relevance of information. However, no main effect of valence or an interaction effect between self-relevance and valence was observed. Further, positive correlations were observed between levels of self-esteem and response within dorsal mPFC (dmPFC) both in the contrast positive-high in self-relevance trials vs positive-low in self-relevance trials and in the contrast negative-low in self-relevance trials vs positive-low in self-relevance trials. These results suggested that the activation of dmPFC may be particularly associated with the processes of self-positivity bias.

  3. Challenging emotional prejudice by changing self-concept: priming independent self-construal reduces racial in-group bias in neural responses to other’s pain

    Science.gov (United States)

    Wu, Bing; Liu, Yi; Wu, Xinhuai; Han, Shihui

    2015-01-01

    Humans show stronger empathy for in-group compared with out-group members’ suffering and help in-group members more than out-group members. Moreover, the in-group bias in empathy and parochial altruism tend to be more salient in collectivistic than individualistic cultures. This work tested the hypothesis that modifying self-construals, which differentiate between collectivistic and individualistic cultural orientations, affects in-group bias in empathy for perceived own-race vs other-race pain. By scanning adults using functional magnetic resonance imaging, we found stronger neural activities in the mid-cingulate, left insula and supplementary motor area (SMA) in response to racial in-group compared with out-group members’ pain after participants had been primed with interdependent self-construals. However, the racial in-group bias in neural responses to others’ pain in the left SMA, mid-cingulate cortex and insula was significantly reduced by priming independent self-construals. Our findings suggest that shifting an individual’s self-construal leads to changes of his/her racial in-group bias in neural responses to others’ suffering. PMID:25605968

  4. Challenging emotional prejudice by changing self-concept: priming independent self-construal reduces racial in-group bias in neural responses to other's pain.

    Science.gov (United States)

    Wang, Chenbo; Wu, Bing; Liu, Yi; Wu, Xinhuai; Han, Shihui

    2015-09-01

    Humans show stronger empathy for in-group compared with out-group members' suffering and help in-group members more than out-group members. Moreover, the in-group bias in empathy and parochial altruism tend to be more salient in collectivistic than individualistic cultures. This work tested the hypothesis that modifying self-construals, which differentiate between collectivistic and individualistic cultural orientations, affects in-group bias in empathy for perceived own-race vs other-race pain. By scanning adults using functional magnetic resonance imaging, we found stronger neural activities in the mid-cingulate, left insula and supplementary motor area (SMA) in response to racial in-group compared with out-group members' pain after participants had been primed with interdependent self-construals. However, the racial in-group bias in neural responses to others' pain in the left SMA, mid-cingulate cortex and insula was significantly reduced by priming independent self-construals. Our findings suggest that shifting an individual's self-construal leads to changes of his/her racial in-group bias in neural responses to others' suffering.

  5. A Comparison of Community College Responders and Nonresponders to the VEDS Student Follow-Up Survey.

    Science.gov (United States)

    Carifio, James; And Others

    1991-01-01

    A survey of respondents and nonrespondents to the Vocational Education Data System's follow-up survey of Massachusetts community college graduates was designed to measure response bias. The survey investigated employment patterns, wages, and degree of job relatedness. Results suggest original data was biased, if at all, toward underestimation, not…

  6. The Sloan Digital Sky Survey Reverberation Mapping Project: An Investigation of Biases in C iv Emission Line Properties

    Science.gov (United States)

    Denney, K. D.; Horne, Keith; Shen, Yue; Brandt, W. N.; Ho, Luis C.; Peterson, B. M.; Richards, Gordon T.; Trump, J. R.; Ge, J.

    2016-06-01

    We investigate the dependence on data quality of quasar properties measured from the C iv emission line region at high redshifts. Our measurements come from 32 epochs of Sloan Digital Sky Survey Reverberation Mapping Project spectroscopic observations of 482 z\\gt 1.46 quasars. We compare the differences between measurements made from the single-epoch (SE) and coadded spectra, focusing on the C iv λ1549 emission line because of its importance for studies of high-redshift quasar demographics and physical properties, including black hole masses. In addition to statistical errors increasing (by factors of ˜2-4), we find increasing systematic offsets with decreasing signal-to-noise ratio (S/N). The systematic difference (measurement uncertainty) in our lowest-S/N ( 10, although offsets in lower-S/N spectra exceed the statistical uncertainties by only a factor of ˜1.5 and may depend on the type of functional fit to the line. Characterizing the C iv line profile by the kurtosis is the least robust property investigated, as the median systematic coadded-SE measurement differences are larger than the statistical uncertainties for all S/N subsamples.

  7. The Sloan Digital Sky Survey Reverberation Mapping Project: An Investigation of Biases in CIV Emission-Line Properties

    CERN Document Server

    Denney, K D; Brandt, W N; Ho, Luis C; Peterson, B M; Richards, Gordon T; Shen, Yue; Trump, J R; Ge, J

    2016-01-01

    We investigate the dependence on data quality of quasar properties measured from the CIV emission line region at high redshifts. Our measurements come from 32 epochs of Sloan Digital Sky Survey (SDSS) Reverberation Mapping Project spectroscopic observations of 482 z>1.46 quasars. We compare the differences between measurements made from the single-epoch and coadded spectra, focusing on the CIV emission line because of its importance for studies of high-redshift quasar demographics and physical properties, including black hole masses. In addition to statistical errors increasing (by factors of ~2-4), we find increasing systematic offsets with decreasing S/N. The systematic difference (measurement uncertainty) in our lowest S/N (10, although offsets in lower S/N spectra exceed the statistical uncertainties by only a factor of ~1.5. Characterizing the CIV line profile by the kurtosis is the least robust property investigated, as the median systematic coadded--single-epoch measurement differences are larger than ...

  8. Evidence-informed person-centred health care (part II): are 'cognitive biases plus' underlying the EBM paradigm responsible for undermining the quality of evidence?

    Science.gov (United States)

    Seshia, Shashi S; Makhinson, Michael; Young, G Bryan

    2014-12-01

    Recently, some leaders of the evidence-based medicine (EBM) movement drew attention to the "unintended" negative consequences associated with EBM. The term 'cognitive biases plus' was introduced in part I to encompass cognitive biases, conflicts of interests, fallacies and certain behaviours. 'Cognitive biases plus' in those closely involved in creating and promoting the EBM paradigm are responsible for their (1) inability to anticipate and then recognize flaws in the tenets of EBM; (2) discounting alternative views; and (3) delaying reform. A narrative review style was used, with methods as in part I. Over the past two decades there has been mounting qualitative and quantitative methodological evidence to suggest that the faith placed in (1) the EBM hierarchy with randomized controlled trials and systematic reviews at the summit; (2) the reliability of biostatistical methods to quantitate data; and (3) the primacy of sources of pre-appraised evidence, is seriously misplaced. Consequently, the evidence that informs person-centred care is compromised. Arguments focusing on 'cognitive biases plus' are offered to support our hypothesis. To the best of our knowledge, EBM proponents have not provided an explanation. Reform is urgently needed to minimize continuing risks to patients. If our hypothesis is correct, then in addition to the suggestions made in part I, deficiencies in the paradigm must be corrected. Meaningful solutions are only possible if the biases of scientific inbreeding and groupthink are minimized by collaboration between EBM leaders and those who have been sounding warning bells. © 2014 John Wiley & Sons, Ltd.

  9. Can Lottery Incentives Boost Web Survey Response Rates? Findings from Four Experiments

    Science.gov (United States)

    Laguilles, Jerold S.; Williams, Elizabeth A.; Saunders, Daniel B.

    2011-01-01

    Institutions of higher education rely on student surveys for a number of purposes, including planning, assessment, and research. Web surveys are especially prevalent given their ease of use and low-cost; yet, obtaining a high response rate is a challenge. Although researchers have investigated the use of incentives in traditional mail surveys,…

  10. College Student Responses to Web and Paper Surveys: Does Mode Matter?

    Science.gov (United States)

    Carini, Robert M.; Hayek, John C.; Kuh, George D.; Kennedy, John M.; Ouimet, Judith A.

    2003-01-01

    Examined the responses of 58,288 college students to 8 scales involving 53 items from the National Survey of Student Engagement to gauge whether individuals respond differently to surveys administered via the Web and paper. Found that mode effects were generally small; however, students who completed the Web-based survey responded more favorably…

  11. Evaluating Reasons for Low Response from Mail Surveys. AIR 1995 Annual Forum Paper.

    Science.gov (United States)

    Westcott, S. Wickes, III; And Others

    A study was undertaken to solicit opinions from alumni on methods that might improve responses from graduate surveys. Two telephone surveys were conducted, one in 1991 which targeted the graduating classes of 1984 and 1989, and the second in 1994 among alumni of the classes of 1991 and 1993. In the 1994 survey information was gathered regarding…

  12. A randomised controlled trial to determine the effect on response of including a lottery incentive in health surveys [ISRCTN32203485

    Directory of Open Access Journals (Sweden)

    Bridge P

    2004-11-01

    Full Text Available Abstract Background Postal questionnaires are an economical and simple method of data collection for research purposes but are subject to non-response bias. Several studies have explored the effect of monetary and non-monetary incentives on response. Recent meta-analyses conclude that financial incentives are an effective way of increasing response rates. However, large surveys rarely have the resources to reward individual participants. Three previous papers report on the effectiveness of lottery incentives with contradictory results. This study aimed to determine the effect of including a lottery-style incentive on response rates to a postal health survey. Methods Randomised controlled trial. Setting: North and West Birmingham. 8,645 patients aged 18 or over randomly selected from registers of eight general practices (family physician practices. Intervention: Inclusion of a flyer and letter with a health questionnaire informing patients that returned questionnaires would be entered into a lottery-style draw for £100 of gift vouchers. Control: Health questionnaire accompanied only by standard letter of explanation. Main outcome measures: Response rate and completion rate to questionnaire. Results 5,209 individuals responded with identical rates in both groups (62.1%. Practice, patient age, sex and Townsend score (a postcode based deprivation measure were identified as predictive of response, with higher response related to older age, being female and living in an area with a lower Townsend score (less deprived. Conclusion This RCT, using a large community based sample, found that the offer of entry into a lottery style draw for £100 of High Street vouchers has no effect on response rates to a postal health questionnaire.

  13. The Impact of Lottery Incentives on Student Survey Response Rates.

    Science.gov (United States)

    Porter, Stephen R.; Whitcomb, Michael E.

    2003-01-01

    A controlled experiment tested the effects of lottery incentives using a prospective college applicant Web survey, with emails sent to more than 9,000 high school students. Found minimal effect of postpaid incentives for increasing levels of incentive. (EV)

  14. Motivation in Business Survey Response Behavior : Influencing motivation to improve survey outcome

    NARCIS (Netherlands)

    Torres van Grinsven, V.

    2015-01-01

    In this dissertation we show theoretical and empirical insights into the concept of motivation in the context of the business and organizational survey task. The research has led to a number of recommendations on how to improve organizational survey and communication design to enhance motivation and

  15. Motivation in Business Survey Response Behavior : Influencing motivation to improve survey outcome

    NARCIS (Netherlands)

    Torres van Grinsven, V.|info:eu-repo/dai/nl/355608510

    2015-01-01

    In this dissertation we show theoretical and empirical insights into the concept of motivation in the context of the business and organizational survey task. The research has led to a number of recommendations on how to improve organizational survey and communication design to enhance motivation and

  16. Investigating bias in psychotherapy with BDSM clients.

    Science.gov (United States)

    Kolmes, Keely; Stock, Wendy; Moser, Charles

    2006-01-01

    There is a concern among consensual BDSM participants that they will receive biased care from mental health professionals. Results are presented of an anonymous Internet-based survey administered to both BDSM-identified individuals who have received psychological care and to mental health professionals. The survey included socio-demographic data and invited participants to write narrative accounts of biased or culturally sensitive care, from which common themes were identified. Mental health providers (N=17) responded in fewer numbers than those who identified as BDSM-identified participants (N=175). Descriptive characteristics of the sample will be discussed. Themes from the qualitative data may be useful in informing the future development of guidelines for practitioners to work more responsibly with clients who identify as members of this sexual minority group.

  17. Nutrient and pesticide contamination bias estimated from field blanks collected at surface-water sites in U.S. Geological Survey Water-Quality Networks, 2002–12

    Science.gov (United States)

    Medalie, Laura; Martin, Jeffrey D.

    2017-08-14

    Potential contamination bias was estimated for 8 nutrient analytes and 40 pesticides in stream water collected by the U.S. Geological Survey at 147 stream sites from across the United States, and representing a variety of hydrologic conditions and site types, for water years 2002–12. This study updates previous U.S. Geological Survey evaluations of potential contamination bias for nutrients and pesticides. Contamination is potentially introduced to water samples by exposure to airborne gases and particulates, from inadequate cleaning of sampling or analytic equipment, and from inadvertent sources during sample collection, field processing, shipment, and laboratory analysis. Potential contamination bias, based on frequency and magnitude of detections in field blanks, is used to determine whether or under what conditions environmental data might need to be qualified for the interpretation of results in the context of comparisons with background levels, drinking-water standards, aquatic-life criteria or benchmarks, or human-health benchmarks. Environmental samples for which contamination bias as determined in this report applies are those from historical U.S. Geological Survey water-quality networks or programs that were collected during the same time frame and according to the same protocols and that were analyzed in the same laboratory as field blanks described in this report.Results from field blanks for ammonia, nitrite, nitrite plus nitrate, orthophosphate, and total phosphorus were partitioned by analytical method; results from the most commonly used analytical method for total phosphorus were further partitioned by date. Depending on the analytical method, 3.8, 9.2, or 26.9 percent of environmental samples, the last of these percentages pertaining to all results from 2007 through 2012, were potentially affected by ammonia contamination. Nitrite contamination potentially affected up to 2.6 percent of environmental samples collected between 2002 and 2006 and

  18. Test of Slope and Intercept Bias in College Admissions: A Response to Aguinis, Culpepper, and Pierce (2010)

    Science.gov (United States)

    Mattern, Krista D.; Patterson, Brian F.

    2013-01-01

    Research on the predictive bias of cognitive tests has generally shown (a) no slope effects and (b) small intercept effects, typically favoring the minority group. Aguinis, Culpepper, and Pierce (2010) simulated data and demonstrated that statistical artifacts may have led to a lack of power to detect slope differences and an overestimate of the…

  19. Test of Slope and Intercept Bias in College Admissions: A Response to Aguinis, Culpepper, and Pierce (2010)

    Science.gov (United States)

    Mattern, Krista D.; Patterson, Brian F.

    2013-01-01

    Research on the predictive bias of cognitive tests has generally shown (a) no slope effects and (b) small intercept effects, typically favoring the minority group. Aguinis, Culpepper, and Pierce (2010) simulated data and demonstrated that statistical artifacts may have led to a lack of power to detect slope differences and an overestimate of the…

  20. [Response rates in three opinion surveys performed through online questionnaires in the health setting].

    Science.gov (United States)

    Aerny Perreten, Nicole; Domínguez-Berjón, Ma Felicitas; Astray Mochales, Jenaro; Esteban-Vasallo, María D; Blanco Ancos, Luis Miguel; Lópaz Pérez, Ma Ángeles

    2012-01-01

    The main advantages of online questionnaires are the speed of data collection and cost savings, but response rates are usually low. This study analyzed response rates and associated factors among health professionals in three opinion surveys in the autonomous region of Madrid. The participants, length of the questionnaire and topic differed among the three surveys. The surveys were conducted by using paid Internet software. The institutional e-mail addresses of distinct groups of health professionals were used. Response rates were highest in hospitals (up to 63%) and administrative services and were lowest in primary care (less than 33%). The differences in response rates were analyzed in primary care professionals according to age, sex and professional category and only the association with age was statistically significant. None of the surveys achieved a response rate of 60%. Differences were observed according to workplace, patterns of Internet usage, and interest in the subject. Copyright © 2011 SESPAS. Published by Elsevier Espana. All rights reserved.

  1. Cognitive Bias by Gender Interaction on N170 Response to Emotional Facial Expressions in Major and Minor Depression.

    Science.gov (United States)

    Wu, Xingqu; Chen, Jiu; Jia, Ting; Ma, Wentao; Zhang, Yan; Deng, Zihe; Yang, Laiqi

    2016-03-01

    States of depression are considered to relate to a cognitive bias reactivity to emotional events. Moreover, gender effect may influence differences in emotional processing. The current study is to investigate whether there is an interaction of cognitive bias by gender on emotional processing in minor depression (MiD) and major depression (MaD). N170 component was obtained during a visual emotional oddball paradigm to manipulate the processing of emotional information in 33 MiD, 36 MaD, and 32 controls (CN). Compared with CN, in male, both MiD and MaD had lower N170 amplitudes for happy faces, but MaD had higher N170 amplitudes for sad faces; in female, both MiD and MaD had lower N170 amplitudes for happy and neutral faces, but higher N170 amplitudes for sad faces. Compared with MaD in male, MiD had higher N170 amplitudes for happy faces, lower N170 amplitudes for sad faces; in female, MiD only had higher N170 amplitudes for sad faces. Interestingly, a negative relationship was observed between N170 amplitude and the HDRS score for identification of happy faces in depressed patients while N170 amplitude was positively correlated with the HDRS score for sad faces identification. These results provide novel evidence for the mood-brightening effect with an interaction of cognitive bias by gender on emotional processing. It further suggests that female depression may be more vulnerable than male during emotional face processing with the unconscious negative cognitive bias and depressive syndromes may exist on a spectrum of severity on emotional face processing.

  2. Understanding Low Survey Response Rates Among Young U.S. Military Personnel

    Science.gov (United States)

    2015-01-01

    two years of the RAND survey. We were unable to include some surveys, such as the 2010 Navy Pregnancy and Parenthood Survey, because response rates...stratified random sampling approach, oversampling women (including sampling all women in the Marine Corps) and oversampling men in the Marine Corps (DMDC...during the first week of basic military training, every Air Force recruit completed a behavioral risk questionnaire on such topics as smoking , alcohol use

  3. 2012 Survey of Active Duty Spouses: Tabulations of Responses

    Science.gov (United States)

    2013-09-30

    unit ................. 88 2012 Survey of Active Duty Spouses DMDC v k. My work unit produces high quality products and services... telework preference. 3. Permanent Change of Station (PCS) Moves—Number of spouse moves, length of time since most recent PCS move, length of time...you agree or disagree with the following statements about your workplace? k. My work unit produces high quality products and services. 1. Strongly

  4. Shortening a survey and using alternative forms of prenotification: Impact on response rate and quality

    Directory of Open Access Journals (Sweden)

    Jenkins Sarah

    2010-06-01

    Full Text Available Abstract Background Evidence suggests that survey response rates are decreasing and that the level of survey response can be influenced by questionnaire length and the use of pre-notification. The goal of the present investigation was determine the effect of questionnaire length and pre-notification type (letter vs. postcard on measures of survey quality, including response rates, response times (days to return the survey, and item nonresponse. Methods In July 2008, the authors randomized 900 residents of Olmsted County, Minnesota aged 25-65 years to one of two versions of the Talley Bowel Disease Questionnaire, a survey designed to assess the prevalence of functional gastrointestinal disorders (FGID. One version was two pages long and the other 4 pages. Using a 2 × 2 factorial design, respondents were randomized to survey length and one of two pre-notification types, letter or postcard; 780 residents ultimately received a survey, after excluding those who had moved outside the county or passed away. Results Overall, the response rates (RR did not vary by length of survey (RR = 44.6% for the 2-page survey and 48.4% for the 4-page or pre-notification type (RR = 46.3% for the letter and 46.8% for the postcard. Differences in response rates by questionnaire length were seen among younger adults who were more likely to respond to the 4-page than the 2-page questionnaire (RR = 39.0% compared to 21.8% for individuals in their 20s and RR = 49.0% compared to 32.3% for those in their 30s. There were no differences across conditions with respect to item non-response or time (days after mailing to survey response. Conclusion This study suggests that the shortest survey does not necessarily provide the best option for increased response rates and survey quality. Pre-notification type (letter or postcard did not impact response rate suggesting that postcards may be more beneficial due to the lower associated costs of this method of contact.

  5. Incomplete categorical data design non-randomized response techniques for sensitive questions in surveys

    CERN Document Server

    Tian, Guo-Liang

    2013-01-01

    Respondents to survey questions involving sensitive information, such as sexual behavior, illegal drug usage, tax evasion, and income, may refuse to answer the questions or provide untruthful answers to protect their privacy. This creates a challenge in drawing valid inferences from potentially inaccurate data. Addressing this difficulty, non-randomized response approaches enable sample survey practitioners and applied statisticians to protect the privacy of respondents and properly analyze the gathered data.Incomplete Categorical Data Design: Non-Randomized Response Techniqu

  6. Resilience and Cognitive Bias in Chinese Male Medical Freshmen.

    Science.gov (United States)

    Peng, Li; Cao, Hong-Wen; Yu, Yongju; Li, Min

    2017-01-01

    Psychological resilience has become a hot issue in positive psychology research. However, little is known about cognitive bias difference of individuals with different resilience levels. This study aimed to explore the characteristics of cognitive bias and its role in Chinese medical freshmen with different resilience levels. 312 Chinese medical freshmen were surveyed by the Chinese version of Connor-Davidson Resilience Scale, 92 of whom were, respectively, allocated into high (n = 46) and low (n = 46) resilient group to complete computerized tests using an attentional shifting task and an emotional picture recognition task. All participants had the highest recognition accuracy toward negative pictures compared to neutral and positive ones. By comparison, it was found that the high-resilient group had a longer recognition response time toward positive emotional pictures, but a shorter response time toward negative emotional pictures, while the low-resilient group had a longer response time toward negative emotional pictures. This study pointed to the association between resilience and cognitive bias. Medical freshmen with different resilience levels showed significant differences in the cognitive bias toward emotional pictures, suggesting that reducing negative cognitive bias and promoting positive cognitive bias could be important targets to increase resilience.

  7. A Validation Study of the Culturally Responsive Teaching Survey

    Science.gov (United States)

    Rhodes, Christy M.

    2017-01-01

    Amidst the ethnic and linguistic diversity in adult English language classes, there is heightened importance to using culturally responsive teaching practices. However, there are limited quantitative examinations of this approach in adult learning environments. The purpose of this investigation was to describe patterns of culturally responsive…

  8. Do release-site biases reflect response to the Earth's magnetic field during position determination by homing pigeons?

    Science.gov (United States)

    Mora, Cordula V; Walker, Michael M

    2009-09-22

    How homing pigeons (Columba livia) return to their loft from distant, unfamiliar sites has long been a mystery. At many release sites, untreated birds consistently vanish from view in a direction different from the home direction, a phenomenon called the release-site bias. These deviations in flight direction have been implicated in the position determination (or map) step of navigation because they may reflect local distortions in information about location that the birds obtain from the geophysical environment at the release site. Here, we performed a post hoc analysis of the relationship between vanishing bearings and local variations in magnetic intensity using previously published datasets for pigeons homing to lofts in Germany. Vanishing bearings of both experienced and naïve birds were strongly associated with magnetic intensity variations at release sites, with 90 per cent of bearings lying within +/-29 degrees of the magnetic intensity slope or contour direction. Our results (i) demonstrate that pigeons respond in an orderly manner to the local structure of the magnetic field at release sites, (ii) provide a mechanism for the occurrence of release-site biases and (iii) suggest that pigeons may derive spatial information from the magnetic field at the release site that could be used to estimate their current position relative to their loft.

  9. Biases from neutrino bias: to worry or not to worry?

    OpenAIRE

    Raccanelli, Alvise; Verde, Licia; Villaescusa-Navarro, Francisco

    2017-01-01

    The relation between the halo field and the matter fluctuations (halo bias), in the presence of massive neutrinos depends on the total neutrino mass, massive neutrinos introduce an additional scale-dependence of the bias which is usually neglected in cosmological analyses. We investigate the magnitude of the systematic effect on interesting cosmological parameters induced by neglecting this scale dependence, finding that while it is not a problem for current surveys, it is non-negligible for ...

  10. Improving Survey Response Rates of School Counselors: Comparing the Use of Incentives

    Science.gov (United States)

    Bauman, Sheri

    2007-01-01

    This article examines the effectiveness of incentives in improving survey response rates of school counselors and compares the findings with those of previously researched populations. A $1 cash incentive increased response rates for a one-wave mailing of a questionnaire, while a raffle opportunity did not. The number and length of optional…

  11. Research on Mail Surveys: Response Rates and Methods in Relation to Population Group and Time.

    Science.gov (United States)

    Boser, Judith A.; Green, Kathy

    The purpose of this review was to look for trends across time in response rates and variables studied for published mail surveys and to compare response rates and variables studied for different target populations. Studies were identified in databases in four fields: education, psychology, business and marketing, and sociology. A total of 225…

  12. The effects of tracking responses and the day of mailing on physician survey response rate: three randomized trials.

    Directory of Open Access Journals (Sweden)

    Elie A Akl

    Full Text Available BACKGROUND: The response rates to physician postal surveys remain modest. The primary objective of this study was to assess the effect of tracking responses on physician survey response rate (i.e., determining whether each potential participant has responded or not. A secondary objective was to assess the effects of day of mailing (Monday vs. Friday on physician survey response rate. METHODS: We conducted 3 randomized controlled trials. The first 2 trials had a 2 x 2 factorial design and tested the effect of day of mailing (Monday vs. Friday and of tracking vs. no tracking responses. The third trial tested the effect of day of mailing (Monday vs. Friday. We meta-analyzed these 3 trials using a random effects model. RESULTS: The total number of participants in the 3 trials was 1339. The response rate with tracked mailing was not statistically different from that with non-tracked mailing by the time of the first reminder (RR = 1.01 95% CI 0.84, 1.22; I²  =  0%. There was a trend towards lower response rate with tracked mailing by the time of the second reminder (RR = 0.91; 95% CI 0.78, 1.06; I²  =  0%. The response rate with mailing on Mondays was not statistically different from that with Friday mailing by the time of first reminder (RR = 1.01; 95% CI 0.87, 1.17; I²  =  0%, and by the time of the 2(nd reminder (RR = 1.08; 95% CI 0.84, 1.39; I²  =  77%. CONCLUSIONS: Tracking response may negatively affect physicians' response rate. The day of mailing does not appear to affect physicians' response rate.

  13. Designing questionnaires: healthcare survey to compare two different response scales

    Science.gov (United States)

    2014-01-01

    Background A widely discussed design issue in patient satisfaction questionnaires is the optimal length and labelling of the answering scale. The aim of the present study was to compare intra-individually the answers on two response scales to five general questions evaluating patients’ perception of hospital care. Methods Between November 2011 and January 2012, all in-hospital patients at a Swiss University Hospital received a patient satisfaction questionnaire on an adjectival scale with three to four labelled categories (LS) and five redundant questions displayed on an 11-point end-anchored numeric scale (NS). The scales were compared concerning ceiling effect, internal consistency (Cronbach’s alpha), individual item answers (Spearman’s rank correlation), and concerning overall satisfaction by calculating an overall percentage score (sum of all answers related to the maximum possible sum). Results The response rate was 41% (2957/7158), of which 2400 (81%) completely filled out all questions. Baseline characteristics of the responders and non-responders were similar. Floor and ceiling effect were high on both response scales, but more pronounced on the LS than on the NS. Cronbach’s alpha was higher on the NS than on the LS. There was a strong individual item correlation between both answering scales in questions regarding the intent to return, quality of treatment and the judgement whether the patient was treated with respect and dignity, but a lower correlation concerning satisfactory information transfer by physicians or nurses, where only three categories were available in the LS. The overall percentage score showed a comparable distribution, but with a wider spread of lower satisfaction in the NS. Conclusions Since the longer scale did not substantially reduce the ceiling effect, the type of questions rather than the type of answering scale could be addressed with a focus on specific questions about concrete situations instead of general questions

  14. Qualitative response models: A survey of methodology and illustrative applications

    Directory of Open Access Journals (Sweden)

    Nojković Aleksandra

    2007-01-01

    Full Text Available This paper introduces econometric modeling with discrete (categorical dependent variables. Such models, commonly referred to as qualitative response (QR models, have become a standard tool of microeconometric analysis. Microeconometric research represents empirical analysis of microdata, i.e. economic information about individuals, households and firms. Microeconometrics has been most widely adopted in various fields, such as labour economics, consumer behavior, or economy of transport. The latest research shows that this methodology can also be successfully transferred to macroeconomic context and applied to time series and panel data analysis in a wider scope. .

  15. Interpatient Variability in Dexmedetomidine Response: A Survey of the Literature

    Directory of Open Access Journals (Sweden)

    Samantha F. Holliday

    2014-01-01

    Full Text Available Fifty-five thousand patients are cared for in the intensive care unit (ICU daily with sedation utilized to reduce anxiety and agitation while optimizing comfort. The Society of Critical Care Medicine (SCCM released updated guidelines for management of pain, agitation, and delirium in the ICU and recommended nonbenzodiazepines, such as dexmedetomidine and propofol, as first line sedation agents. Dexmedetomidine, an alpha-2 agonist, offers many benefits yet its use is mired by the inability to consistently achieve sedation goals. Three hypotheses including patient traits/characteristics, pharmacokinetics in critically ill patients, and clinically relevant genetic polymorphisms that could affect dexmedetomidine response are presented. Studies in patient traits have yielded conflicting results regarding the role of race yet suggest that dexmedetomidine may produce more consistent results in less critically ill patients and with home antidepressant use. Pharmacokinetics of critically ill patients are reported as similar to healthy individuals yet wide, unexplained interpatient variability in dexmedetomidine serum levels exist. Genetic polymorphisms in both metabolism and receptor response have been evaluated in few studies, and the results remain inconclusive. To fully understand the role of dexmedetomidine, it is vital to further evaluate what prompts such marked interpatient variability in critically ill patients.

  16. Choice of rating scale labels: implication for minimizing patient satisfaction response ceiling effect in telemedicine surveys.

    Science.gov (United States)

    Masino, Caterina; Lam, Tony C M

    2014-12-01

    Lack of response variability is problematic in surveys because of its detrimental effects on sensitivity and consequently reliability of the responses. In satisfaction surveys, this problem is caused by the ceiling effect resulting from high satisfaction ratings. A potential solution strategy is to manipulate the labels of the rating scale to create greater discrimination of responses on the high end of the response continuum. This study examined the effects of a positive-centered scale on the distribution and reliability of telemedicine satisfaction responses in a highly positive respondent population. In total, 216 telemedicine participants were randomly assigned to one of three experimental conditions as defined by the form of Likert scale: (1) 5-point Balanced Equal-Interval, (2) 5-point Positive-Packed, and (3) 5-point Positive-Centered Equal-Interval. Although the study findings were not statistically significant, partially because of sample size, the distribution and internal consistency reliability of responses occurred in the direction hypothesized. Loading the rating scale with more positive labels appears to be a useful strategy for reducing the ceiling effect and increases the discrimination ability of survey responses. The current research provides a survey design strategy to minimize ceiling effects. Although the findings provide some evidence suggesting the benefit of using rating scales loaded with positive labels, more research is needed to confirm this, as well as extend it to examine other types of rating scales and the interaction between rating scale formats and respondent characteristics.

  17. Codon Bias and Mutability in HIV Sequences

    CERN Document Server

    Waelbroeck, H

    1997-01-01

    A survey of the patterns of synonymous codon preferences in the HIV env gene reveals a relation between the codon bias and the mutability requirements in different regions in the protein. At hypervariable regions in $gp120$, one finds a greater proportion of codons that tend to mutate non-synonymously, but to a target that is similar in hydrophobicity and volume. We argue that this strategy results from a compromise between the selective pressure placed on the virus by the induced immune response, which favours amino acid substitutions in the complementarity determining regions, and the negative selection against missense mutations that violate structural constraints of the env protein.

  18. An interdependent analytic approach to explaining the evolution of NGOs, social movements, and biased government response to AIDS and tuberculosis in Brazil.

    Science.gov (United States)

    Gómez, Eduardo J

    2013-02-01

    The politics of government response to health epidemics is a new area of scholarly research. Nevertheless, to date scholars have not considered how social science theory can be used and interdependently linked to provide a more thorough discussion of civil societal and national government response to different types of health epidemics. Introducing what I call an interdependent analytic framework of government response to epidemics, this article illustrates how social science theories can be interdependently linked and applied to help explain the evolutionary role of interest groups and social movements in response to AIDS and tuberculosis in Brazil, and when and why the government eventually responded more aggressively to AIDS but not tuberculosis. Evidence from Brazil suggests that the policy influence of interest groups and social movements evolves over time and is more influential after the national government implements new policies; moreover, this response is triggered by the rise of international pressures and government reputation building, not civil society. I highlight new areas of research that the framework provides and provide examples of how this approach can help explain civil societal and biased government responses to different types of epidemics in other nations.

  19. Zing Zing Bang Bang: How Do You Know What She Really Meant. Gender Bias in Response to Irony: The Role of Who is Speaking to Whom

    Directory of Open Access Journals (Sweden)

    Milanowicz Anna

    2016-12-01

    Full Text Available Literature points towards the role of context in irony interpretation and the existence of gender differences in language use. We decided to examine the influence of interlocutors’ gender stereotypes on interpreting and reacting to ironic criticism in conversation. To this end, we designed two experiments gathering participants’ responses to the same ironic utterances voiced both by women and by men in control and gender stereotype activation conditions. Results of the first experiment showed that women tended to use irony significantly more often when responding to a man than to another woman. The second, ongoing experiment will additionally examine participants’ response times and total time of utterance in respect to their addressee’s gender. The results are discussed with regard to the social comparison theory (Turner, Hogg, Oakes, Reicher, & Wetherell, 1987 and the linguistic intergroup bias theory (Wigboldus & Douglas, 2007.

  20. Mitigating Hypothetical Bias in Stated Preference Data: Evidence from Sports Tourism

    OpenAIRE

    John Whitehead; Melissa S. Weddell; Pete Groothuis

    2014-01-01

    One of the major criticisms of stated preference data is hypothetical bias. Using a unique data set of both stated and actual behavior we test for hypothetical bias of stated preference survey responses. We consider whether respondents tend to overstate their participatory sporting event behavior ex ante when compared to their actual behavior at different registration fees. We find that behavioral intentions accurately predicts actual behavior at a middle level of respondent certainty, over p...

  1. The Effect of Social Desirability Bias on Willingness-To-Pay for Organic Beef.

    OpenAIRE

    Cheek, Lindsey

    2007-01-01

    Researchers regularly conduct willingness-to-pay or valuation studies for product marketing or public policy purposes. However, a large volume of research suggests valuation tools such as conjoint analysis may be subject to social desirability bias, where subjects misrepresent their true preferences to create a favorable impression. The objective of this study is to measure the effects of social desirability bias on conjoint survey responses. Consumers were asked to rank organic ground beef r...

  2. Take Care Of Home And Family, Honey, And Let Me Take Care Of The Money. Gender Bias And Credit Market Barriers For Female Entrepreneurs

    NARCIS (Netherlands)

    Ongena, S.; Popov, A.

    2013-01-01

    Abstract We identify the causal effect of gender bias on access to finance. We extract an exogenous measure of gender bias from survey responses by descendants of US immigrants on questions about the role of women in society. We then investigate a detailed dataset on small business firms from 17

  3. Take Care Of Home And Family, Honey, And Let Me Take Care Of The Money. Gender Bias And Credit Market Barriers For Female Entrepreneurs

    NARCIS (Netherlands)

    Ongena, S.; Popov, A.

    2013-01-01

    Abstract We identify the causal effect of gender bias on access to finance. We extract an exogenous measure of gender bias from survey responses by descendants of US immigrants on questions about the role of women in society. We then investigate a detailed dataset on small business firms from 17 cou

  4. The strange case of online surveys: response issues and respondent characteristics

    DEFF Research Database (Denmark)

    Adamsen, Jannie Mia; Rundle-Thiele, Sharyn; Mehnert, Christina

    2011-01-01

    This research contributes to existing knowledge about collecting data online by analysing multiple data sets on key criteria including overall representativeness of the samples, response and break-off rates, timeliness of response and reminder effects. Across eight online surveys that initially...... in responses on the preference measures for Leaders, Early or Late Majority or Laggards and secondly, we have only considered the demographic characteristics of responders. The information can be utilised by researchers in the planning and management process of online surveys, especially since the results...... a reminder 48-72 hours after the initial invitation and closing the survey one to two days later; based on our results this time-wise approach still captures 90% of respondents. This study must be viewed in light of some key limitations. Firstly, we have not considered whether there are differences...

  5. Promoting quality of care in disaster response: A survey of core surgical competencies.

    Science.gov (United States)

    Wong, Evan G; Razek, Tarek; Elsharkawi, Hossam; Wren, Sherry M; Kushner, Adam L; Giannou, Christos; Khwaja, Kosar A; Beckett, Andrew; Deckelbaum, Dan L

    2015-07-01

    Recent humanitarian crises have led to a call for professionalization of the humanitarian field, but core competencies for the delivery of surgical care have yet to be established. The objective of this study was to survey surgeons with experience in disaster response to identify surgical competencies required to be effective in these settings. An online survey elucidating demographic information, scope of practice, and previous experience in global health and disaster response was transmitted to surgeons from a variety of surgical societies and nongovernmental organizations. Participants were provided with a list of 111 operative procedures and were asked to identify those deemed essential to the toolset of a frontline surgeon in disaster response via a Likert scale. Responses from personnel with experience in disaster response were contrasted with those from nonexperienced participants. A total of 147 surgeons completed the survey. Participants held citizenship in 22 countries, were licensed in 30 countries, and practiced in >20 countries. Most respondents (56%) had previous experience in humanitarian response. The majority agreed or strongly agreed that formal training (54%), past humanitarian response (94%), and past global health experiences (80%) provided adequate preparation. The most commonly deemed important procedures included control of intraabdominal hemorrhage (99%), abdominal packing for trauma (99%), and wound debridement (99%). Procedures deemed important by experienced personnel spanned multiple specialties. This study addressed specifically surgical competencies in disaster response. We provide a list of operative procedures that should set the stage for further structured education programs. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Differential effects of pre and post-payment on neurologists' response rates to a postal survey

    Directory of Open Access Journals (Sweden)

    Wessely Simon C

    2010-10-01

    Full Text Available Abstract Background Monetary incentives are an effective way of increasing response rates to surveys, though they are generally less effective in physicians, and are more effective when the incentive is paid up-front rather than when made conditional on completion. Methods In this study we examine the effectiveness of pre- and post-completion incentives on the response rates of all the neurologists in the UK to a survey about conversion disorder, using a cluster randomised controlled design. A postal survey was sent to all practicing consultant neurologists, in two rounds, including either a book token, the promise of a book token, or nothing at all. Results Three hundred and fifty-one of 591 eligible neurologists completed the survey, for a response rate of 59%. While the post-completion incentive exerted no discernible influence on response rates, a pre-completion incentive did, with an odds-ratio of 2.1 (95% confidence interval 1.5 - 3.0. Conclusions We conclude that neurologists, in the UK at least, may be influenced to respond to a postal survey by a pre-payment incentive but are unaffected by a promised reward.

  7. Factors affecting study efficiency and item non-response in health surveys in developing countries: the Jamaica national healthy lifestyle survey

    Directory of Open Access Journals (Sweden)

    Bennett Franklyn

    2007-02-01

    Full Text Available Abstract Background Health surveys provide important information on the burden and secular trends of risk factors and disease. Several factors including survey and item non-response can affect data quality. There are few reports on efficiency, validity and the impact of item non-response, from developing countries. This report examines factors associated with item non-response and study efficiency in a national health survey in a developing Caribbean island. Methods A national sample of participants aged 15–74 years was selected in a multi-stage sampling design accounting for 4 health regions and 14 parishes using enumeration districts as primary sampling units. Means and proportions of the variables of interest were compared between various categories. Non-response was defined as failure to provide an analyzable response. Linear and logistic regression models accounting for sample design and post-stratification weighting were used to identify independent correlates of recruitment efficiency and item non-response. Results We recruited 2012 15–74 year-olds (66.2% females at a response rate of 87.6% with significant variation between regions (80.9% to 97.6%; p Conclusion Informative health surveys are possible in developing countries. While survey response rates may be satisfactory, item non-response was high in respect of income and sexual practice. In contrast to developed countries, non-response to questions on income is higher and has different correlates. These findings can inform future surveys.

  8. Gene Vaccination to Bias the Immune Response to Amyloid-β Peptide as Therapy for Alzheimer Disease

    Science.gov (United States)

    Qu, Baoxi; Rosenberg, Roger N.; Li, Liping; Boyer, Philip J.; Johnston, Stephen A.

    2006-01-01

    Background The amyloid-β (Aβ) peptide has a central role in the neurodegeneration of Alzheimer disease (AD). Immunization of AD transgenic mice with Aβ1–42 (Aβ42) peptide reduces both the spatial memory impairments and AD-like neuropathologic changes in these mice. Therapeutic immunization with Aβ in patients with AD was shown to be effective in reducing Aβ deposition, but studies were discontinued owing to the development of an autoimmune, cell-mediated meningoencephalitis. We hypothesized that gene vaccination could be used to generate an immune response to Aβ42 that produced antibody response but avoided an adverse cell-mediated immune effect. Objective To develop an effective genetic immunization approach for treatment and prevention of AD without causing an autoimmune, cell-mediated meningoencephalitis. Methods Mice were vaccinated with a plasmid that encodes Aβ42, administered by gene gun. The immune response of the mice to Aβ42 was monitored by measurement of (1) antibody levels by enzyme-linked immunosorbent assay (ELISA) and Western blot and (2) Aβ42-specific T-cell response as measured by interferon-γ enzyme-linked immunospot (ELISPOT) assay. Results Gene-gun delivery of the mouse Aβ42 dimer gene induced significant humoral immune responses in BALB/c wild-type mice after 3 vaccinations in 10-day intervals. All 3 mice in the treated group showed significant humoral immune responses. The ELISPOT assay for interferon-γ release with mouse Aβ42 peptide and Aβ9–18 showed no evident cytotoxic T-lymphocyte response. We further tested the responses of wild-type BALB/c mice to the monomer Aβ42 gene vaccine. Western blot evaluation showed both human and mouse Aβ monomer gene vaccine elicited detectable humoral immune responses. We also introduced the human Aβ42 monomer gene vaccine into AD double transgenic mice APPswe/PSEN1(A246E). Mice were vaccinated with plasmids that encode Aβ1–42 and Aβ1–16, or with plasmid without the A

  9. A Procedure to Assess Interviewer Effects on Nonresponse Bias

    Directory of Open Access Journals (Sweden)

    Geert Loosveldt

    2014-02-01

    Full Text Available It is generally accepted that interviewers have a considerable effect on survey response. The difference between response success and failure does not only affect the response rate, but can also influence the composition of the realized sample or respondent set, and consequently introduce nonresponse bias. To measure these two different aspects of the obtained sample, response propensities will be used. They have an aggregate mean and variance that can both be used to construct quality indicators for the obtained sample of respondents. As these propensities can also be measured on the interviewer level, this allows evaluation of the interviewer group and of the extent to which individual interviewers contribute to a biased respondent set. In this article, a procedure based on a multilevel model with random intercepts and random slopes is elaborated and illustrated. The results show that the procedure is informative to detect influential interviewers with an impact on nonresponse basis.

  10. Survey Satisficing Inflates Stereotypical Responses in Online Experiment: The Case of Immigration Study

    Directory of Open Access Journals (Sweden)

    Asako Miura

    2016-10-01

    Full Text Available Though survey satisficing, grudging cognitive efforts required to provide optimal answers in the survey response process, poses a serious threat to the validity of online experiments, a detailed explanation of the mechanism has yet to be established. Focusing on attitudes toward immigrants, we examined the mechanism by which survey satisficing distorts treatment effect estimates in online experiments. We hypothesized that satisficers would display more stereotypical responses than non-satisficers would when presented with stereotype-disconfirming information about an immigrant. Results of two experiments largely supported our hypotheses. Satisficers, whom we identified through an instructional manipulation check (IMC, processed information about immigrants’ personality traits congruently with the stereotype activated by information provided about nationality. The significantly shorter vignette reading time of satisficers corroborates their time-efficient impression formation based on stereotyping. However, the shallow information processing of satisficers can be rectified by alerting them to their inattentiveness through use of a repeated IMC.

  11. Text analysis of open-ended survey responses : a complementary method to preference mapping

    NARCIS (Netherlands)

    ten Kleij, F; Musters, PAD

    2003-01-01

    The present study illustrates the use of computer-aided text analysis to evaluate the content of open-ended survey responses. During an in-hall test, different varieties of mayonnaise were evaluated by 165 respondents on a 10-point liking scale, with the option to freely comment on these assessments

  12. Publication bias in epidemiological studies.

    Science.gov (United States)

    Siddiqi, Nazish

    2011-06-01

    Communication of research findings is the utmost responsibility of all scientists. Publication bias occurs if scientific studies with negative or null results fail to get published. This can happen due to bias in submitting, reviewing, accepting, publishing or aggregating scientific literature that fails to show positive results on a particular topic. Publication bias can make scientific literature unrepresentative of the actual research studies. This can give the reader a false impression about the beneficial effects of a particular treatment or intervention and can influence clinical decision making. Publication bias is more common than it is actually considered to be, but there are ways to detect and prevent it. This paper comments on the occurrence, types and consequences of publication bias and the strategies employed to detect and control it.

  13. Measuring the mental health care system responsiveness: results of an outpatient survey in Tehran

    Directory of Open Access Journals (Sweden)

    Setareh eForouzan

    2016-01-01

    Full Text Available AbstractAs explained by the World Health Organisation (WHO in 2000, the concept of health system responsiveness is one of the core goals of health systems. Since 2000, further efforts have been made to measure health system responsiveness and the factors affecting responsiveness, yet few studies have applied responsiveness concepts to the evaluation of mental health systems. The present study aims to measure responsiveness and its related domains in the mental health care system of Tehran. Utilising the same method used by the WHO for its responsiveness survey, responsiveness for outpatient mental health care was evaluated using a validated Farsi questionnaire. A sample of 500 public mental health service users in Tehran participated and subsequently completed the questionnaire. On average, 47% of participants reported experiencing poor responsiveness. Among responsiveness domains, confidentiality and dignity were the best performing factors while autonomy, access to care and quality of basic amenities were the worst performing. Respondents who reported their social status as low were more likely to experience poor responsiveness overall. Autonomy, quality of basic amenities and clear communication were responsiveness dimensions that performed poorly but were considered to be important by study participants. In summary, the study suggests that measuring responsiveness could provide guidance for further development of mental health care systems to become more patient orientated and provide patients with more respect.

  14. Lateral bias of agonistic responses to mirror images and morphological asymmetry in the Siamese fighting fish (Betta splendens).

    Science.gov (United States)

    Takeuchi, Yuichi; Hori, Michio; Myint, Omar; Kohda, Masanori

    2010-03-17

    Behavioural laterality (e.g., during social interactions) is often observed at the individual level in lower vertebrates such as fish, whereas population-level laterality is observed in many higher vertebrates. Population-level laterality can be explained mainly by internal factors (e.g., cerebral lateralization), whereas little is known about the behavioural mechanisms underlying individual-level laterality. Recently, it was revealed that many fish have asymmetrical body morphology, but the relationship between asymmetric morphology and social behaviours has been rarely examined. Here we report the relationship between lateralized eye use during aggressive displays (e.g., body posture) of male Siamese fighting fish, Betta splendens, toward their own mirror image and morphological asymmetry. Of 25 males, five exhibited significantly more leftward eye use during left displays, and eight males exhibited predominantly rightward eye use during right displays. Morphological measurement results for the craniovertebral angle and opercular area showed that the craniovertebral angle and opercular area displayed antisymmetry and fluctuating asymmetry, respectively. We found that lateralized eye use during agonistic responses by each fish was associated with the craniovertebral angle, but not with operculum size; lefties (left-curved body) showed mainly left eye use (during left-side displays), and righties (right-curved body) demonstrated the opposite. We suggest that antisymmetric morphologies, such as head incline, are potentially useful for studying the association between cerebral lateralization and individual laterality of behavioural responses. Further, we propose that in fish, morphological asymmetry is related to laterality in various behaviours.

  15. Fore and aft elastic response characteristics of 34 x 9.9, type 7, 14 ply-rating aircraft tires of bias-ply, bias-belted, and radial-belted design. M.S. Thesis - George Washington Univ., May 1973; [static and rolling tests on dry concrete pavements

    Science.gov (United States)

    Tanner, J. A.

    1974-01-01

    An investigation was conducted to determine the fore-and-aft elastic response characteristics of 34 x 9.9, type VII, 14 ply-rating aircraft tires of bias-ply, bias-belted, and radial-belted design. The investigation consisted of static and rolling tests on dry concrete pavements at the Langley aircraft landing loads and traction facility; statistical techniques which related the measured tire elastic characteristics to variations in the vertical load, inflation pressure, braking force and/or tire vertical deflection; and a semiempirical analysis which related the tire elastic behavior to measured wheel slippage during steady-state braking. The bias-belted tire developed the largest spring constant value for most loading conditions; the radial-belted tire, the smallest. The elastic response of the tire free periphery to static braking included both tread stretch and carcass torsional wind-up about the axle for the bias-ply and bias-belted tires and carcass wind-up alone for the radial-belted tire.

  16. Fair reckoning: a qualitative investigation of responses to an economic health resource allocation survey.

    Science.gov (United States)

    Giacomini, Mita; Hurley, Jeremiah; DeJean, Deirdre

    2014-04-01

    To investigate how participants in an economic resource allocation survey construct notions of fairness. Qualitative interview study guided by interpretive grounded theory methods. Qualitative interviews were conducted with volunteer university- (n=39) and community-based (n =7) economic survey participants. INTERVENTION OR MAIN VARIABLES STUDIED: We explored how participants constructed meanings to guide or explain fair survey choices, focusing on rationales, imagery and additional desired information not provided in the survey scenarios. Data were transcribed and coded into qualitative categories. Analysis iterated with data collection iterated through three waves of interviews. Participants compared the survey dilemmas to domains outside the health system. Most compared them with other micro-level, inter-personal sharing tasks. Participants raised several fairness-relevant factors beyond need or capacity to benefit. These included age, weight, poverty, access to other options and personal responsibility for illness; illness duration, curability or seriousness; life expectancy; possibilities for sharing; awareness of other's needs; and ability to explain allocations to those affected. They also articulated a fairness principle little considered by equity theories: that everybody must get something and nobody should get nothing. Lay criteria for judging fairness are myriad. Simple scenarios may be used to investigate lay commitments to abstract principles. Although principles are the focus of analysis and inference, participants may solve simplified dilemmas by imputing extraneous features to the problem or applying unanticipated principles. These possibilities should be taken into account in the design of resource allocation surveys eliciting the views of the public. © 2012 John Wiley & Sons Ltd.

  17. Cross-linked survey analysis is an approach for separating cause and effect in survey research.

    Science.gov (United States)

    Redelmeier, Donald A; Thiruchelvam, Deva; Lustig, Andrew J

    2015-01-01

    We developed a new research approach, called cross-linked survey analysis, to explore how an acute exposure might lead to changes in survey responses. The goal was to identify associations between exposures and outcomes while reducing some ambiguities related to interpreting cause and effect in survey responses from a population-based community questionnaire. Cross-linked survey analysis differs from a cross-sectional, longitudinal, and panel survey analysis by individualizing the timeline to the unique history of each respondent. Cross-linked survey analysis, unlike a repeated-measures self-matching design, does not track changes in a repeated survey question given to the same respondent at multiple time points. Pilot data from three analyses (n = 1,177 respondents) illustrate how a cross-linked survey analysis can control for population shifts, temporal trends, and reverse causality. Accompanying graphs provide an intuitive display to readers, summarize results, and show differences in response distributions. Population-based individual-level linkages also reduce selection bias and increase statistical power compared with a single-center cross-sectional survey. Cross-linked survey analysis has limitations related to unmeasured confounding, pragmatics, survivor bias, statistical models, and the underlying artifacts in survey responses. We suggest that a cross-linked survey analysis may help in epidemiology science using survey data. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Prospective evaluation of direct approach with a tablet device as a strategy to enhance survey study participant response rate

    Directory of Open Access Journals (Sweden)

    Parker Melissa J

    2012-10-01

    Full Text Available Abstract Background Investigators conduct survey studies for a variety of reasons. Poor participant response rates are common, however, and may limit the generalizability and utility of results. The objective of this study was to determine whether direct approach with a tablet device enhances survey study participant response rate and to assess participants’ experiences with this mode of survey administration. Findings An interventional study nested within a single center survey study was conducted at McMaster Children’s Hospital. The primary outcome was the ability to achieve of a survey study response rate of 70% or greater. Eligible participants received 3 email invitations (Week 0, 2, 4 to complete a web-based (Survey Monkey survey. The study protocol included plans for a two-week follow-up phase (Phase 2 where non-responders were approached by a research assistant and invited to complete an iPad-based version of the survey. The Phase 1 response rate was 48.7% (56/115. Phase 2 effectively recruited reluctant responders, increasing the overall response rate to 72.2% (83/115. On a 7-point Likert scale, reluctant responders highly rated their enjoyment (mean 6.0, sd 0.83 [95% CI: 5.7-6.3] and ease of use (mean 6.7, sd 0.47 [95% CI: 6.5-6.9] completing the survey using the iPad. Reasons endorsed for Phase 2 participation included: direct approach (81%, immediate survey access (62%, and the novelty of completing a tablet-based survey (54%. Most reluctant responders (89% indicated that a tablet-based survey is their preferred method of survey completion. Conclusions Use of a tablet-based version of the survey was effective in recruiting reluctant responders and this group reported positive experiences with this mode of survey administration.

  19. Understanding Spanish-Language Response in a National Health Communication Survey: Implications for Health Communication Research.

    Science.gov (United States)

    Ramírez, A Susana; Willis, Gordon; Rutten, Lila Finney

    2017-05-01

    Spanish-speaking Latinos account for 13% of the U.S. population yet are chronically under-represented in national surveys; additionally, the response quality suffers from low literacy rates and translation challenges. These are the same issues that health communicators face when understanding how best to communicate important health information to Latinos. The Health Information National Trends Survey (HINTS) offers a unique opportunity to understand the health communication landscape and information needs of the U.S. We describe the challenges in recruiting Spanish-speaking HINTS respondents and strategies used to improve rates and quality of responses among Spanish-speaking Latinos. Cognitive interviewing techniques helped to better understand how Spanish-speaking Latinos were interpreting the survey questions, and the extent to which these interpretations matched English-speaking respondents' interpretations. Some Spanish-speaking respondents had difficulty with the questions because of a lack of access to health care. Additionally, Spanish-speaking respondents had a particularly hard time answering questions that were presented in a grid format. We describe the cognitive interview process, and consider the impact of format changes on Spanish-speaking people's responses and response quality. We discuss challenges that remain in understanding health information needs of non-English-speakers.

  20. Racially Biased Policing: Determinants of Citizen Perceptions

    Science.gov (United States)

    Weitzer, Ronald; Tuch, Steven A.

    2005-01-01

    The current controversy surrounding racial profiling in America has focused renewed attention on the larger issue of racial bias by the police. Yet little is known about the extent of police racial bias and even less about public perceptions of the problem. This article analyzes recent national survey data on citizens' views of and reported…

  1. Effect of Upper-Cycle Temperature on the Load-Biased, Strain-Temperature Response of NiTi

    Science.gov (United States)

    Padula, Santo; Qiu, Shipeng; Gaydosh, Darrell; Noebe, Ronald; Bigelow, Glen; Garg, Anita; Vaidyanathan, Raj

    2012-12-01

    Over the past decade, interest in shape-memory-alloy based actuators has increased as the primary benefits of these solid-state devices have become more apparent. However, much is still unknown about the characteristic behavior of these materials when used in actuator applications. Recently, we showed that the maximum temperature reached during thermal cycling under isobaric conditions could significantly affect the observed mechanical response of NiTi (55 wt pct Ni), especially the amount of transformation strain available for actuation and thus work output. The investigation we report here extends that original work to (1) ascertain whether increases in the upper-cycle temperature would produce additional changes in the work output of the material, which has a stress-free austenite finish temperature of 386 K (113 °C), and (2) determine the optimum cyclic conditions. Thus, isobaric, thermal-cycle experiments were conducted on the aforementioned alloy at various stresses from 50 to 300 MPa using upper-cycle temperatures of 438 K, 473 K, 503 K, 533 K, 563 K, 593 K, and 623 K (165 °C, 200 °C, 230 °C, 260 °C, 290 °C, 320 °C, and 350 °C). The data indicated that the amount of applied stress influenced the transformation strain, as would be expected. However, the maximum temperature reached during the thermal excursion also plays an equally significant role in determining the transformation strain, with the maximum transformation strain observed during thermal cycling to 563 K (290 °C). In situ neutron diffraction at stress and temperature showed that the differences in transformation strain were mostly related to changes in martensite texture when cycling to different upper-cycle temperatures. Hence, understanding this effect is important to optimizing the operation of SMA-based actuators and could lead to new methods for processing and training shape-memory alloys for optimal performance.

  2. Development of Survey Scales for Measuring Exposure and Behavioral Responses to Disruptive Intraoperative Behavior.

    Science.gov (United States)

    Villafranca, Alexander; Hamlin, Colin; Rodebaugh, Thomas L; Robinson, Sandra; Jacobsohn, Eric

    2017-09-10

    Disruptive intraoperative behavior has detrimental effects to clinicians, institutions, and patients. How clinicians respond to this behavior can either exacerbate or attenuate its effects. Previous investigations of disruptive behavior have used survey scales with significant limitations. The study objective was to develop appropriate scales to measure exposure and responses to disruptive behavior. We obtained ethics approval. The scales were developed in a sequence of steps. They were pretested using expert reviews, computational linguistic analysis, and cognitive interviews. The scales were then piloted on Canadian operating room clinicians. Factor analysis was applied to half of the data set for question reduction and grouping. Item response analysis and theoretical reviews ensured that important questions were not eliminated. Internal consistency was evaluated using Cronbach α. Model fit was examined on the second half of the data set using confirmatory factor analysis. Content validity of the final scales was re-evaluated. Consistency between observed relationships and theoretical predictions was assessed. Temporal stability was evaluated on a subsample of 38 respondents. A total of 1433 and 746 clinicians completed the exposure and response scales, respectively. Content validity indices were excellent (exposure = 0.96, responses = 1.0). Internal consistency was good (exposure = 0.93, responses = 0.87). Correlations between the exposure scale and secondary measures were consistent with expectations based on theory. Temporal stability was acceptable (exposure = 0.77, responses = 0.73). We have developed scales measuring exposure and responses to disruptive behavior. They generate valid and reliable scores when surveying operating room clinicians, and they overcome the limitations of previous tools. These survey scales are freely available.

  3. SURVEY

    DEFF Research Database (Denmark)

    SURVEY er en udbredt metode og benyttes inden for bl.a. samfundsvidenskab, humaniora, psykologi og sundhedsforskning. Også uden for forskningsverdenen er der mange organisationer som f.eks. konsulentfirmaer og offentlige institutioner samt marketingsafdelinger i private virksomheder, der arbejder...... med surveys. Denne bog gennemgår alle surveyarbejdets faser og giver en praktisk indføring i: • design af undersøgelsen og udvælgelse af stikprøver, • formulering af spørgeskemaer samt indsamling og kodning af data, • metoder til at analysere resultaterne...

  4. Mapping HIV-1 vaccine induced T-cell responses: bias towards less-conserved regions and potential impact on vaccine efficacy in the Step study.

    Directory of Open Access Journals (Sweden)

    Fusheng Li

    Full Text Available T cell directed HIV vaccines are based upon the induction of CD8+ T cell memory responses that would be effective in inhibiting infection and subsequent replication of an infecting HIV-1 strain, a process that requires a match or near-match between the epitope induced by vaccination and the infecting viral strain. We compared the frequency and specificity of the CTL epitope responses elicited by the replication-defective Ad5 gag/pol/nef vaccine used in the Step trial with the likelihood of encountering those epitopes among recently sequenced Clade B isolates of HIV-1. Among vaccinees with detectable 15-mer peptide pool ELISpot responses, there was a median of four (one Gag, one Nef and two Pol CD8 epitopes per vaccinee detected by 9-mer peptide ELISpot assay. Importantly, frequency analysis of the mapped epitopes indicated that there was a significant skewing of the T cell response; variable epitopes were detected more frequently than would be expected from an unbiased sampling of the vaccine sequences. Correspondingly, the most highly conserved epitopes in Gag, Pol, and Nef (defined by presence in >80% of sequences currently in the Los Alamos database www.hiv.lanl.gov were detected at a lower frequency than unbiased sampling, similar to the frequency reported for responses to natural infection, suggesting potential epitope masking of these responses. This may be a generic mechanism used by the virus in both contexts to escape effective T cell immune surveillance. The disappointing results of the Step trial raise the bar for future HIV vaccine candidates. This report highlights the bias towards less-conserved epitopes present in the same vaccine used in the Step trial. Development of vaccine strategies that can elicit a greater breadth of responses, and towards conserved regions of the genome in particular, are critical requirements for effective T-cell based vaccines against HIV-1.ClinicalTrials.gov NCT00849680, A Study of Safety, Tolerability

  5. Dropout Rates and Response Times of an Occupation Search Tree in a Web Survey

    Directory of Open Access Journals (Sweden)

    Tijdens Kea

    2014-03-01

    Full Text Available Occupation is key in socioeconomic research. As in other survey modes, most web surveys use an open-ended question for occupation, though the absence of interviewers elicits unidentifiable or aggregated responses. Unlike other modes, web surveys can use a search tree with an occupation database. They are hardly ever used, but this may change due to technical advancements. This article evaluates a three-step search tree with 1,700 occupational titles, used in the 2010 multilingual WageIndicator web survey for UK, Belgium and Netherlands (22,990 observations. Dropout rates are high; in Step 1 due to unemployed respondents judging the question not to be adequate, and in Step 3 due to search tree item length. Median response times are substantial due to search tree item length, dropout in the next step and invalid occupations ticked. Overall the validity of the occupation data is rather good, 1.7-7.5% of the respondents completing the search tree have ticked an invalid occupation.

  6. Evaluating audio computer assisted self-interviews in urban south African communities: evidence for good suitability and reduced social desirability bias of a cross-sectional survey on sexual behaviour

    Directory of Open Access Journals (Sweden)

    Beauclair Roxanne

    2013-01-01

    Full Text Available Abstract Background Efficient HIV prevention requires accurate identification of individuals with risky sexual behaviour. However, self-reported data from sexual behaviour surveys are prone to social desirability bias (SDB. Audio Computer-Assisted Self-Interviewing (ACASI has been suggested as an alternative to face-to-face interviewing (FTFI, because it may promote interview privacy and reduce SDB. However, little is known about the suitability and accuracy of ACASI in urban communities with high HIV prevalence in South Africa. To test this, we conducted a sexual behaviour survey in Cape Town, South Africa, using ACASI methods. Methods Participants (n = 878 answered questions about their sexual relationships on a touch screen computer in a private mobile office. We included questions at the end of the ACASI survey that were used to assess participants’ perceived ease of use, privacy, and truthfulness. Univariate logistic regression models, supported by multivariate models, were applied to identify groups of people who had adverse interviewing experiences. Further, we constructed male–female ratios of self-reported sexual behaviours as indicators of SDB. We used these indicators to compare SDB in our survey and in recent FTFI-based Demographic and Health Surveys (DHSs from Lesotho, Swaziland, and Zimbabwe. Results Most participants found our methods easy to use (85.9%, perceived privacy (96.3% and preferred ACASI to other modes of inquiry (82.5% when reporting on sexual behaviours. Unemployed participants and those in the 40–70 year old age group were the least likely to find our methods easy to use (OR 0.69; 95% CI: 0.47–1.01 and OR 0.37; 95% CI: 0.23–0.58, respectively. In our survey, the male–female ratio for reporting >2 sexual partners in the past year, a concurrent relationship in the past year, and > 2 sexual partners in a lifetime was 3.4, 2.6, and 1.2, respectively— far lower than the ratios observed in the Demographic

  7. A survey of hospitals to determine the prevalence and characteristics of healthcare coalitions for emergency preparedness and response.

    Science.gov (United States)

    Rambhia, Kunal J; Waldhorn, Richard E; Selck, Frederick; Mehta, Ambereen Kurwa; Franco, Crystal; Toner, Eric S

    2012-09-01

    Previous reports have identified the development of healthcare coalitions as the foundation for disaster response across the United States. This survey of acute care hospitals characterizes the current status of participation by US hospitals in healthcare coalitions for emergency preparedness planning and response. The survey results show the nearly universal nature of a coalition approach to disaster response. The results suggest a need for wide stakeholder involvement but also for flexibility in structure and organization. Based on the survey results, the authors make recommendations to guide the further development of healthcare coalitions and to improve local and national response to disasters.

  8. A literature survey of private sector methods of determining personal financial responsibility

    OpenAIRE

    Bodzin, Martin Bradley

    1988-01-01

    Approved for public release; distribution is unlimited Credit grantors and employers have two clearly established methods-- judgmental and empirically derived--of determining personal financial responsibility that can be used as a basis for accepting or rejecting credit or job applicants. This thesis is a literature survey and analysis of those methods. The foundations of the two methods are examined and models of the empirically derived method are discussed. The pa...

  9. Are Divorce Studies Trustworthy? The Effects of Survey Nonresponse and Response Errors

    OpenAIRE

    Mitchell, Colter

    2010-01-01

    Researchers rely on relationship data to measure the multifaceted nature of families. This article speaks to relationship data quality by examining the ramifications of different types of error on divorce estimates, models predicting divorce behavior, and models employing divorce as a predictor. Comparing matched survey and divorce certificate information from the 1995 Life Events and Satisfaction Study (N = 1,811) showed that nonresponse error is responsible for the majority of the error in ...

  10. Patient and dental student responses to a survey about AIDS in the dental setting.

    Science.gov (United States)

    Thaker, H J; Gobetti, J P; Green, T G

    1993-01-01

    The purpose of the study was to gain information about patients' and dental students' attitudes concerning AIDS and dentistry. Opinions of patients and students at a Midwestern dental school were surveyed. The dental students' responses were not as consistent as the patient responses. Both groups felt there was a risk to patients and dentists of HIV infection. Both groups had confidence in the CDC infection control guidelines. The patient responses to the testing questions were significantly more positive than the student responses. The patients responded positively to the concept that healthcare professionals had the right to ask patients to be tested and to being required to be tested if a healthcare provider is accidentally stuck by a needle used on a patient. The dental students were more cautious with both issues. Patients would use knowledge about a healthcare provider's HIV status and the office treatment of AIDS patients to determine if they should continue treatment at that dental office.

  11. Responses to GM food content in context with food integrity issues: results from Australian population surveys.

    Science.gov (United States)

    Mohr, Philip; Golley, Sinéad

    2016-01-25

    This study examined community responses to use of genetically modified (GM) content in food in the context of responses to familiar food additives by testing an empirically and theoretically derived model of the predictors of responses to both GM content and food integrity issues generally. A nationwide sample of 849 adults, selected at random from the Australian Electoral Roll, responded to a postal Food and Health Survey. Structural equation modelling analyses confirmed that ratings of general concern about food integrity (related to the presence of preservatives and other additives) strongly predicted negativity towards GM content. Concern about food integrity was, in turn, predicted by environmental concern and health engagement. In addition, both concern about food integrity generally and responses to GM content specifically were weakly predicted by attitudes to benefits of science and an intuitive (i.e., emotionally-based) reasoning style. Data from a follow-up survey conducted under the same conditions (N=1184) revealed that ratings of concern were significantly lower for use of genetic engineering in food than for four other common food integrity issues examined. Whereas the question of community responses to GM is often treated as a special issue, these findings support the conclusion that responses to the concept of GM content in food in Australia are substantially a specific instance of a general sensitivity towards the integrity of the food supply. They indicate that the origins of responses to GM content may be largely indistinguishable from those of general responses to preservatives and other common food additives. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Internal Medicine Residents' Perceived Responsibility for Patients at Hospital Discharge: A National Survey.

    Science.gov (United States)

    Young, Eric; Stickrath, Chad; McNulty, Monica C; Calderon, Aaron J; Chapman, Elizabeth; Gonzalo, Jed D; Kuperman, Ethan F; Lopez, Max; Smith, Christopher J; Sweigart, Joseph R; Theobald, Cecelia N; Burke, Robert E

    2016-12-01

    Medical residents are routinely entrusted with transitions of care, yet little is known about the duration or content of their perceived responsibility for patients they discharge from the hospital. To examine the duration and content of internal medicine residents' perceived responsibility for patients they discharge from the hospital. The secondary objective was to determine whether specific individual experiences and characteristics correlate with perceived responsibility. Multi-site, cross-sectional 24-question survey delivered via email or paper-based form. Internal medicine residents (post-graduate years 1-3) at nine university and community-based internal medicine training programs in the United States. Perceived responsibility for patients after discharge as measured by a previously developed single-item tool for duration of responsibility and novel domain-specific questions assessing attitudes towards specific transition of care behaviors. Of 817 residents surveyed, 469 responded (57.4 %). One quarter of residents (26.1 %) indicated that their responsibility for patients ended at discharge, while 19.3 % reported perceived responsibility extending beyond 2 weeks. Perceived duration of responsibility did not correlate with level of training (P = 0.57), program type (P = 0.28), career path (P = 0.12), or presence of burnout (P = 0.59). The majority of residents indicated they were responsible for six of eight transitional care tasks (85.1-99.3 % strongly agree or agree). Approximately half of residents (57 %) indicated that it was their responsibility to directly contact patients' primary care providers at discharge. and 21.6 % indicated that it was their responsibility to ensure that patients attended their follow-up appointments. Internal medicine residents demonstrate variability in perceived duration of responsibility for recently discharged patients. Neither the duration nor the content of residents' perceived responsibility was

  13. Pairing call-response surveys and distance sampling for a mammalian carnivore

    Science.gov (United States)

    Hansen, Sara J. K.; Frair, Jacqueline L.; Underwood, Harold B.; Gibbs, James P.

    2015-01-01

    Density estimates accounting for differential animal detectability are difficult to acquire for wide-ranging and elusive species such as mammalian carnivores. Pairing distance sampling with call-response surveys may provide an efficient means of tracking changes in populations of coyotes (Canis latrans), a species of particular interest in the eastern United States. Blind field trials in rural New York State indicated 119-m linear error for triangulated coyote calls, and a 1.8-km distance threshold for call detectability, which was sufficient to estimate a detection function with precision using distance sampling. We conducted statewide road-based surveys with sampling locations spaced ≥6 km apart from June to August 2010. Each detected call (be it a single or group) counted as a single object, representing 1 territorial pair, because of uncertainty in the number of vocalizing animals. From 524 survey points and 75 detections, we estimated the probability of detecting a calling coyote to be 0.17 ± 0.02 SE, yielding a detection-corrected index of 0.75 pairs/10 km2 (95% CI: 0.52–1.1, 18.5% CV) for a minimum of 8,133 pairs across rural New York State. Importantly, we consider this an index rather than true estimate of abundance given the unknown probability of coyote availability for detection during our surveys. Even so, pairing distance sampling with call-response surveys provided a novel, efficient, and noninvasive means of monitoring populations of wide-ranging and elusive, albeit reliably vocal, mammalian carnivores. Our approach offers an effective new means of tracking species like coyotes, one that is readily extendable to other species and geographic extents, provided key assumptions of distance sampling are met.

  14. Cognitive biases and language universals

    CERN Document Server

    Baronchelli, Andrea; Puglisi, Andrea

    2013-01-01

    Language universals have been longly attributed to an innate Universal Grammar. An alternative explanation states that linguistic universals emerged independently in every language in response to shared cognitive, though non language-specific, biases. A computational model has recently shown how this could be the case, focusing on the paradigmatic example of the universal properties of color naming patterns, and producing results in accurate agreement with the experimental data. Here we investigate thoroughly the role of a cognitive bias in the framework of this model. We study how, and to what extent, the structure of the bias can influence the corresponding linguistic universal patterns. We show also that the cultural history of a group of speakers introduces population-specific constraints that act against the uniforming pressure of the cognitive bias, and we clarify the interplay between these two forces. We believe that our simulations can help to shed light on the possible mechanisms at work in the evol...

  15. Effects of Using Visual Design Principles to Group Response Options in Web Surveys

    Directory of Open Access Journals (Sweden)

    Michael J. Stern

    2006-03-01

    Full Text Available In this paper, we show that in Web questionnaires verbal and visual languages can be used to create groups and subgroups of information, which influence how respondents process Web questionnaires. Following Schwarz (1996; and also Schwarz, Grayson, & Knäuper, 1998 we argue that respondents act as cooperative communicators who use formal features of the questionnaire to help guide them through the survey conversation. Using data from three Web surveys of random samples of Washington State University undergraduates, we found that when response options are placed in close graphical proximity to each other and separated from other options, respondents perceive visual subgroups of the categories, increasing the likelihood that they select an answer from each subgroup. We also found that graphical proximity creates subgroups with and without the use of category heading to describe the subgroups and that the addition of a verbal instruction to “please select the best answer” encouraged respondents to select one answer from each subgroup instead of overriding the effects of proximity. In addition, the effects of grouping were consistent when the subgroups were positioned either vertically or horizontally in relation to each other. Lastly, we found that the effects of visual grouping are consistent across both opinion- and behavior/fact-based questions, although the effects appear to be greater on opinion-based questions. Our findings contribute to the increasing evidence that both verbal and visual languages influence how respondents process and respond to surveys. Because respondents interpret the verbal and graphical features of survey questionnaires as relevant to answering the survey, inadvertent or stylistic design changes can influence how respondents process and respond to survey questions.

  16. Person-fit statistics, response sets and survey participation in a population-based cohort study

    Directory of Open Access Journals (Sweden)

    Müller Jörg M.

    2015-01-01

    Full Text Available Person-fit methodology is a promising technique for identifying subjects whose test scores have questionable validity. Less is known however about this technique’s ability to predict survey participation longitudinally. This study presents theory-derived expectations related to social desirability, the tendency for extreme responding and traitedness for specific deviating answer patterns and an expected consistence of person-fit scores across 27 personality scales. Data from 5,114 subjects (Amelang, 1997 were reanalysed with a polytomous-Rasch model to estimate scale scores and von Davier and Molenaar’s (2003 person-fit statistics. The person-fit statistics of the 27 scales were examined together with the 27 person parameter scores in one common factor analysis. The person-fit scores served as indicators of the latent factor ‘scalability’ while the person-parameter scores were considered to index the bias introduced by social desirability. The sign of factor loadings showed consistency and validity of the tendency for social desirability and extreme responding. Moreover, the personfit- based subject classification derived from the baseline data was able to predict subjects’ participation at a 8,5-year follow-up. However, the nature of those associations was contrary to our predictions. The discussion addresses explanations and practical implications, but also the limitations pertaining to the identification and interpretation of person-fit scores.

  17. Survey of state and tribal emergency response capabilities for radiological transportation incidents

    Energy Technology Data Exchange (ETDEWEB)

    Vilardo, F J; Mitter, E L; Palmer, J A; Briggs, H C; Fesenmaier, J [Indiana Univ., Bloomington, IN (USA). School of Public and Environmental Affairs

    1990-05-01

    This publication is the final report of a project to survey the fifty states, the District of Columbia, Puerto Rico, and selected Indian Tribal jurisdictions to ascertain their emergency-preparedness planning and capabilities for responding to transportation incidents involving radioactive materials. The survey was conducted to provide the Nuclear Regulatory Commission and other federal agencies with information concerning the current level of emergency-response preparedness of the states and selected tribes and an assessment of the changes that have occurred since 1980. There have been no major changes in the states' emergency-response planning strategies and field tactics. The changes noted included an increased availability of dedicated emergency-response vehicles, wider availability of specialized radiation-detection instruments, and higher proportions of police and fire personnel with training in the handling of suspected radiation threats. Most Indian tribes have no capability to evaluate suspected radiation threats and have no formal relations with emergency-response personnel in adjacent states. For the nation as a whole, the incidence of suspected radiation threats declined substantially from 1980 to 1988. 58 tabs.

  18. The Survey of Hospitals Affiliated with Kerman University of Medical Sciences in Preparedness Response to Disasters

    Directory of Open Access Journals (Sweden)

    Mahmood Nekoei-Moghadam

    2016-12-01

    Full Text Available Background and Objectives : Natural and man-made disasters always threaten human lives and properties. Iran as one of the disastrous countries has experienced both natural and man-made disasters. Preparedness is one of the vital elements in response to disasters. So, this study was arranged and carried out with the aim of measuring preparedness of hospitals affiliated with Kerman University of Medical Sciences in response to disasters. Material and Methods: This cross-sectional descriptive study was performed in four hospitals affiliated with Kerman University of Medical Sciences in 2015. A satisfactorily valid (kappa: 0.8 and reliable checklist was used. Data were analyzed using descriptive statistics in SPSS version 17. Results: The surveyed hospitals with the total score of 67 % were in good condition in response to disasters. The emergency departments (83%, reception (75%, communication (69%, education (70%, supply services (61%, human sources (71% and command (79% also acquired good scores. Discharge units (60%, traffic (55% and security (53% were in moderate condition in preparedness. In necessary fields for response to disasters, the whole research units acquired 67% which showed good condition in this field. Conclusion: The surveyed hospitals were in prepared and suitable condition in the emergency departments, reception, communication, education, human sources and command. In order to improve and enhance the preparedness, a schedule plan should be programmed for some elements such as discharge, transfer, traffic, security and six-crucial elements of the field.

  19. Mental health first aid responses of the public: results from an Australian national survey

    Directory of Open Access Journals (Sweden)

    Kitchener Betty A

    2005-02-01

    Full Text Available Abstract Background The prevalence of mental disorders is so high that members of the public will commonly have contact with someone affected. How they respond to that person (the mental health first aid response may affect outcomes. However, there is no information on what members of the public might do in such circumstances. Methods In a national survey of 3998 Australian adults, respondents were presented with one of four case vignettes and asked what they would do if that person was someone they had known for a long time and cared about. There were four types of vignette: depression, depression with suicidal thoughts, early schizophrenia, and chronic schizophrenia. Verbatim responses to the open-ended question were coded into categories. Results The most common responses to all vignettes were to encourage professional help-seeking and to listen to and support the person. However, a significant minority did not give these responses. Much less common responses were to assess the problem or risk of harm, to give or seek information, to encourage self-help, or to support the family. Few respondents mentioned contacting a professional on the person's behalf or accompanying them to a professional. First aid responses were generally more appropriate in women, those with less stigmatizing attitudes, and those who correctly identified the disorder in the vignette. Conclusions There is room for improving the range of mental health first aid responses in the community. Lack of knowledge of mental disorders and stigmatizing attitudes are important barriers to effective first aid.

  20. Cetacean behavioral responses to noise exposure generated by seismic surveys: how to mitigate better?

    Directory of Open Access Journals (Sweden)

    Clara Monaco

    2016-09-01

    Full Text Available Cetaceans use sound in many contexts, such as in social interactions, as well as to forage and to react in dangerous situations. Little information exists to describe how they respond physically and behaviorally to intense and long-term noise levels. Effects on cetaceans from seismic survey activities need to be understood in order to determine detailed acoustic exposure guidelines and to apply appropriated mitigation measures. This study examines direct behavioral responses of cetaceans in the southern Mediterranean Sea during seismic surveys with large airgun arrays (volume up to 5200 ci used in the TOMO-ETNA active seismic experiment of summer 2014. Wide Angle Seismic and Multi-Channel Seismic surveys had carried out with refraction and reflection seismic methods, producing about 25,800 air-gun shots. Visual monitoring undertaken in the 26 daylights of seismic exploration adopted the protocol of the Joint Nature Conservation Committee. Data recorded were analyzed to examine effects on cetaceans. Sighting rates, distance and orientation from the airguns were compared for different volume categories of the airgun arrays. Results show that cetaceans can be disturbed by seismic survey activities, especially during particularly events. Here we propose many integrated actions to further mitigate this exposure and implications for management.

  1. Harmonizing Measures of Cognitive Performance Across International Surveys of Aging Using Item Response Theory.

    Science.gov (United States)

    Chan, Kitty S; Gross, Alden L; Pezzin, Liliana E; Brandt, Jason; Kasper, Judith D

    2015-12-01

    To harmonize measures of cognitive performance using item response theory (IRT) across two international aging studies. Data for persons ≥65 years from the Health and Retirement Study (HRS, N = 9,471) and the English Longitudinal Study of Aging (ELSA, N = 5,444). Cognitive performance measures varied (HRS fielded 25, ELSA 13); 9 were in common. Measurement precision was examined for IRT scores based on (a) common items, (b) common items adjusted for differential item functioning (DIF), and (c) DIF-adjusted all items. Three common items (day of date, immediate word recall, and delayed word recall) demonstrated DIF by survey. Adding survey-specific items improved precision but mainly for HRS respondents at lower cognitive levels. IRT offers a feasible strategy for harmonizing cognitive performance measures across other surveys and for other multi-item constructs of interest in studies of aging. Practical implications depend on sample distribution and the difficulty mix of in-common and survey-specific items. © The Author(s) 2015.

  2. The '10 Excess' Phenomenon in Responses to Survey Questions on Happiness.

    Science.gov (United States)

    Brulé, Gaël; Veenhoven, Ruut

    2017-01-01

    Happiness in nations is typically measured in surveys using a single question. A common question is: 'all things considered, how satisfied or dissatisfied are you with your life as-a-whole these days on a scale from 0 to 10?'. The responses typically follow a uni-modal distribution with highest frequencies between 5 and 8. Yet in some nations, the percentage of 10 responses stands out and is higher than the percentage of 9 responses. This is particularly present in Latin America and in the Middle East. In this paper we explore the prevalence of the '10-excess' pattern and check some possible explanations. We conclude that the 10-excess phenomenon is partly due to cultural influence.

  3. Awareness Reduces Racial Bias

    OpenAIRE

    2014-01-01

    Can raising awareness of racial bias subsequently reduce that bias? We address this question by exploiting the widespread media attention highlighting racial bias among professional basketball referees that occurred in May 2007 following the release of an academic study. Using new data, we confirm that racial bias persisted in the years after the study's original sample, but prior to the media coverage. Subsequent to the media coverage though, the bias completely disappeared. We examine poten...

  4. Sesgos de género en el lenguaje de los cuestionarios de la Encuesta Nacional de Salud 2003 Gender bias in the language of the health questionnaire of the Spanish National Health Survey 2003

    Directory of Open Access Journals (Sweden)

    María Teresa Ruiz-Cantero

    2006-03-01

    Full Text Available Para identificar la posible existencia de sesgos de género en el lenguaje del cuestionario de Adultos y del cuestionario de Hogar de la Encuesta Nacional de Salud (ENS de 2003, se analiza su lenguaje/estilo respecto a generalizaciones imprecisas, desigualdad de trato por uso de términos que reflejan estereotipos sociales y ocultan desigualdad de roles sociales y discordancia gramatical de género. Se evidencia la presencia de sesgos lingüísticos en su mayoría de tipo léxico, pues ambos cuestionarios utilizan el masculino singular refiriéndose al conjunto de informantes (p. ej., cuidador, empleador, trabajador, médico, entrevistado o entrevistador. También se observan estereotipos de género cuando al utilizar el término «cuidador» se hace referencia a mujeres para este rol, o se ejemplifica la profesión con ocupaciones clásicamente masculinas. Igualmente, cuando se juntan parentescos masculinos/femeninos (p. ej., hermano/a en la misma categoría se ocultan desigualdades de género respecto a roles sociales. Se concluye que las mujeres están menos presentes formalmente que los hombres en la ENS de 2003. Esta experiencia puede contribuir a observar y eliminar sesgos de género del lenguaje en otros cuestionarios.To identify possible gender bias in the language of the adults' and children's questionnaires of the Spanish National Health Survey, 2003, its style and language was analyzed for inaccurate generalizations, inequalities due to the use of terms that reflect social stereotypes and hide unequal social roles, and grammatical gender disagreement. Both questionnaires show language bias, mainly lexical, as they use masculine singular nouns to refer to all individuals (for example, carer, employer, worker, doctor, interviewer, interviewee. Gender stereotypes are reinforced by the use of the term «carer», referring to women, and by examples of jobs traditionally done by men. Equally, specific sex denomination for relatives in the

  5. Comparison of self-administered survey questionnaire responses collected using mobile apps versus other methods.

    Science.gov (United States)

    Marcano Belisario, José S; Jamsek, Jan; Huckvale, Kit; O'Donoghue, John; Morrison, Cecily P; Car, Josip

    2015-07-27

    Self-administered survey questionnaires are an important data collection tool in clinical practice, public health research and epidemiology. They are ideal for achieving a wide geographic coverage of the target population, dealing with sensitive topics and are less resource-intensive than other data collection methods. These survey questionnaires can be delivered electronically, which can maximise the scalability and speed of data collection while reducing cost. In recent years, the use of apps running on consumer smart devices (i.e., smartphones and tablets) for this purpose has received considerable attention. However, variation in the mode of delivering a survey questionnaire could affect the quality of the responses collected. To assess the impact that smartphone and tablet apps as a delivery mode have on the quality of survey questionnaire responses compared to any other alternative delivery mode: paper, laptop computer, tablet computer (manufactured before 2007), short message service (SMS) and plastic objects. We searched MEDLINE, EMBASE, PsycINFO, IEEEXplore, Web of Science, CABI: CAB Abstracts, Current Contents Connect, ACM Digital, ERIC, Sociological Abstracts, Health Management Information Consortium, the Campbell Library and CENTRAL. We also searched registers of current and ongoing clinical trials such as ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform. We also searched the grey literature in OpenGrey, Mobile Active and ProQuest Dissertation & Theses. Lastly, we searched Google Scholar and the reference lists of included studies and relevant systematic reviews. We performed all searches up to 12 and 13 April 2015. We included parallel randomised controlled trials (RCTs), crossover trials and paired repeated measures studies that compared the electronic delivery of self-administered survey questionnaires via a smartphone or tablet app with any other delivery mode. We included data obtained from

  6. A survey on the Relationship between Social Responsibility and Social Capital

    Directory of Open Access Journals (Sweden)

    Moahmmadtaghi Iman

    2010-04-01

    Full Text Available AbstractThis article aims to explain the relationship between social responsibility and social capital ofthe young with the age range of 18 to 29 in the Shiraz city. Development of social responsibilityand commitment are important subjects which are considered more than cognitive subjects byscholars (Fathi Azar, 1373:180. Social responsibility is a part of socialization process. The mostimportant factors which have major roles in socialization are culture, family and social institutions.Social responsibility is a skill of doing behavior which is evaluated by people. These skills canmake positive and successfully results and lead to personal and group’s satisfaction. Otherwise, thelake of social responsibility results to less confidence and cooperation. In this article theresearchers used survey method and questionnaire to collect the data. Sample size is 386 youngwhich were selected randomly. The result of multiple regression showed the effects of the variablesare as follows: social capital (beta=0.27, self esteem (beta=0. 27, age (beta=0. 21 and gender(beta=0. 22 have significant and positive relations with social responsibility. These variablesexplain 20 percent of the variation of social responsibility (R2=0.20. In path analysis model,maximum direct effect belongs to social capital and maximum indirect effect belongs to mother’seducation.

  7. Social Responsibility of the Hospitals in Isfahan City, Iran: Results from a Cross-Sectional Survey

    Directory of Open Access Journals (Sweden)

    Mahmoud Keyvanara

    2015-08-01

    Full Text Available Background Changes in modern societies develop the perception that the external environment is essential in organization’s practices, especially in the way they deal with aspects such as human rights, community needs, market demands and environmental interests. These issues are usually under the umbrella of the concept of social responsibility. Given the importance of this concept in the context of health care delivery, suggesting a new paradigm in hospital governance, the aim of this study was to measure the social responsibility in hospitals. Methods A cross-sectional survey was employed to collect data from a sample of 946 hospital staff of Isfahan city. Data was obtained by structured and valid self-administrated questionnaire and analyzed by descriptive and analytic statistics using SPSS. Results The mean score of hospitals’ social responsibility was 3.0 compared with the justified range from 1.0 to 5.0. Results showed that there was a significant relationship between social responsibility score and hospitals’ ownership (public or private. Also, there was no significant relationship between social responsibility and type of hospital specialty. Conclusion It is recommended that hospital managers develop and apply appropriate policies and strategies to improve their hospitals’ social responsibility level, especially through concentrating on their staff’s working environment.

  8. Social responsibility of the hospitals in Isfahan city, Iran: Results from a cross-sectional survey.

    Science.gov (United States)

    Keyvanara, Mahmoud; Sajadi, Haniye Sadat

    2015-02-12

    Changes in modern societies develop the perception that the external environment is essential in organization's practices, especially in the way they deal with aspects such as human rights, community needs, market demands and environmental interests. These issues are usually under the umbrella of the concept of social responsibility. Given the importance of this concept in the context of health care delivery, suggesting a new paradigm in hospital governance, the aim of this study was to measure the social responsibility in hospitals. A cross-sectional survey was employed to collect data from a sample of 946 hospital staff of Isfahan city. Data was obtained by structured and valid self-administrated questionnaire and analyzed by descriptive and analytic statistics using SPSS. The mean score of hospitals' social responsibility was 3.0 compared with the justified range from 1.0 to 5.0. Results showed that there was a significant relationship between social responsibility score and hospitals' ownership (public or private). Also, there was no significant relationship between social responsibility and type of hospital specialty. It is recommended that hospital managers develop and apply appropriate policies and strategies to improve their hospitals' social responsibility level, especially through concentrating on their staff's working environment. © 2015 by Kerman University of Medical Sciences.

  9. Observations and Models of Galaxy Assembly Bias

    Science.gov (United States)

    Campbell, Duncan A.

    2017-01-01

    The assembly history of dark matter haloes imparts various correlations between a halo’s physical properties and its large scale environment, i.e. assembly bias. It is common for models of the galaxy-halo connection to assume that galaxy properties are only a function of halo mass, implicitly ignoring how assembly bias may affect galaxies. Recently, programs to model and constrain the degree to which galaxy properties are influenced by assembly bias have been undertaken; however, the extent and character of galaxy assembly bias remains a mystery. Nevertheless, characterizing and modeling galaxy assembly bias is an important step in understanding galaxy evolution and limiting any systematic effects assembly bias may pose in cosmological measurements using galaxy surveys.I will present work on modeling and constraining the effect of assembly bias in two galaxy properties: stellar mass and star-formation rate. Conditional abundance matching allows for these galaxy properties to be tied to halo formation history to a variable degree, making studies of the relative strength of assembly bias possible. Galaxy-galaxy clustering and galactic conformity, the degree to which galaxy color is correlated between neighbors, are sensitive observational measures of galaxy assembly bias. I will show how these measurements can be used to constrain galaxy assembly bias and the peril of ignoring it.

  10. Response to an Online Version of a PRAMS-like Survey in South Dakota.

    Science.gov (United States)

    Binkley, Teresa; Beare, Tianna; Minett, Maggie; Koepp, Kriston; Wey, Howard; Specker, Bonny

    2017-02-01

    Objectives Increasing response rates for research surveys is challenging, especially in minority populations. A unique minority group in South Dakota is the American Indian (AI) representing about 9 % of the state's population and 15 % of the births. The purpose of this study was to determine race differences among White, AI, and Other Races (OR) in contact, participation, and response rates in the South Dakota Pregnancy Risk Assessment Monitoring System (SDPRAMS). We determined response rates of an online version and evaluated demographic characteristics associated with online response. Methods The SDPRAMS was sent to 1814 mothers randomly sampled from 2014 birth certificate files. Results The weighted response rate was 71.3 %, and varied significantly among the three races: 79.1 % for White race, 48.6 % for AI race, and 60.6 % for OR (p online than AI and OR (35, 25 and 26 %, respectively; p = 0.001); no difference between AI and OR. Online responders were more likely to be married, educated beyond high school and having annual incomes ≥$25,000 (p ≤ 0.01 for all), but only education (p online respondents used a smartphone to respond (p = 0.01). Conclusions Response rates differed among races. An online version of the PRAMS is a viable method of response to offer participants. Response to the online version via smartphone may increase response from minority populations, emphasizing the importance of mobile friendly formats.

  11. Transfer RNA gene numbers may not be completely responsible for the codon usage bias in asparagine, isoleucine, phenylalanine, and tyrosine in the high expression genes in bacteria.

    Science.gov (United States)

    Satapathy, Siddhartha Sankar; Dutta, Malay; Buragohain, Alak Kumar; Ray, Suvendra Kumar

    2012-08-01

    It is generally believed that the effect of translational selection on codon usage bias is related to the number of transfer RNA genes in bacteria, which is more with respect to the high expression genes than the whole genome. Keeping this in the background, we analyzed codon usage bias with respect to asparagine, isoleucine, phenylalanine, and tyrosine amino acids. Analysis was done in seventeen bacteria with the available gene expression data and information about the tRNA gene number. In most of the bacteria, it was observed that codon usage bias and tRNA gene number were not in agreement, which was unexpected. We extended the study further to 199 bacteria, limiting to the codon usage bias in the two highly expressed genes rpoB and rpoC which encode the RNA polymerase subunits β and β', respectively. In concordance with the result in the high expression genes, codon usage bias in rpoB and rpoC genes was also found to not be in agreement with tRNA gene number in many of these bacteria. Our study indicates that tRNA gene numbers may not be the sole determining factor for translational selection of codon usage bias in bacterial genomes.

  12. An Experimental Examination of Readers' Perceptions of Media Bias.

    Science.gov (United States)

    D'Alessio, Dave

    2003-01-01

    Explores perceptions of media bias by manipulating expectations of bias and news topic. Explains that university students read dummy newspaper articles and then responded to a survey. Concludes that readers were more likely to designate material opposing their own views as biased. (PM)

  13. Understanding the Diffusion of Efficient Consumer Response: an Australian survey study

    Directory of Open Access Journals (Sweden)

    Sherah Kurnia

    2002-05-01

    Full Text Available Efficient Consumer Response (ECR is designed to make the grocery industry more efficient. Although it originated in the US, the concept has been adopted in many regions. To enrich the findings of the existing studies that indicate a slow diffusion rate of ECR, this study examines ECR adoption in Australia by conducting a survey. The findings suggest that in Australia, ECR diffusion has also been slow. Differences in barriers, perceptions, and benefits experienced between manufacturers and retailers discovered in this study suggest that Australian retailers are leading manufacturers in ECR implementation and that they experience more benefits than manufacturers.

  14. Using a retrospective pretest instead of a conventional pretest is replacing biases: a qualitative study of cognitive processes underlying responses to thentest items.

    Science.gov (United States)

    Taminiau-Bloem, Elsbeth F; Schwartz, Carolyn E; van Zuuren, Florence J; Koeneman, Margot A; Visser, Mechteld R M; Tishelman, Carol; Koning, Caro C E; Sprangers, Mirjam A G

    2016-06-01

    The thentest design aims to detect and control for recalibration response shift. This design assumes (1) more consistency in the content of the cognitive processes underlying patients' quality of life (QoL) between posttest and thentest assessments than between posttest and pretest assessments; and (2) consistency in the time frame and description of functioning referenced at pretest and thentest. Our objective is to utilize cognitive interviewing to qualitatively examine both assumptions. We conducted think-aloud interviews with 24 patients with cancer prior to and after radiotherapy to elicit cognitive processes underlying their assessment of seven EORTC QLQ-C30 items at pretest, posttest and thentest. We used an analytic scheme based on the cognitive process models of Tourangeau et al. and Rapkin and Schwartz that yielded five cognitive processes. We subsequently used this input for quantitative analysis of count data. Contrary to expectation, the number of dissimilar cognitive processes between posttest and thentest was generally larger than between pretest and posttest across patients. Further, patients considered a range of time frames when answering the thentest questions. Moreover, patients' description at the thentest of their pretest functioning was often not similar to that which was noted at pretest. Items referring to trouble taking a short walk, overall health and QoL were most often violating the assumptions. Both assumptions underlying the thentest design appear not to be supported by the patients' cognitive processes. Replacing the conventional pretest-posttest design with the thentest design may simply be replacing one set of biases with another.

  15. Assessing nonresponse bias at follow-up in a large prospective cohort of relatively young and mobile military service members

    Directory of Open Access Journals (Sweden)

    Hooper Tomoko

    2010-10-01

    Full Text Available Abstract Background Nonresponse bias in a longitudinal study could affect the magnitude and direction of measures of association. We identified sociodemographic, behavioral, military, and health-related predictors of response to the first follow-up questionnaire in a large military cohort and assessed the extent to which nonresponse biased measures of association. Methods Data are from the baseline and first follow-up survey of the Millennium Cohort Study. Seventy-six thousand, seven hundred and seventy-five eligible individuals completed the baseline survey and were presumed alive at the time of follow-up; of these, 54,960 (71.6% completed the first follow-up survey. Logistic regression models were used to calculate inverse probability weights using propensity scores. Results Characteristics associated with a greater probability of response included female gender, older age, higher education level, officer rank, active-duty status, and a self-reported history of military exposures. Ever smokers, those with a history of chronic alcohol consumption or a major depressive disorder, and those separated from the military at follow-up had a lower probability of response. Nonresponse to the follow-up questionnaire did not result in appreciable bias; bias was greatest in subgroups with small numbers. Conclusions These findings suggest that prospective analyses from this cohort are not substantially biased by non-response at the first follow-up assessment.

  16. Employers' and employees' views on responsibilities for career management in nursing: a cross-sectional survey.

    Science.gov (United States)

    Philippou, Julia

    2015-01-01

    To examine nurse employees' and employers' views about responsibilities for managing nurses' careers. Career management policies are associated with cost savings, in terms of workforce recruitment and retention and an increase in job and career satisfaction. In nursing, responsibility for career management remains relatively unexplored. A multicenter, cross-sectional questionnaire survey. Data were collected from 871 nurse employees and employers in the British National Health Service. The study was conducted in 2008, a period when policy reforms aimed at modernizing the healthcare workforce in England. In the current discussions in Europe and the USA about the future of nursing, these data reveal insights not previously reported. Exploratory analyses were undertaken using descriptive and inferential statistics. The analysis indicated a temporal dimension to career management responsibilities. Short-term responsibilities for securing funding and time for development lay more with employers. Medium-term responsibilities for assessing nurses' strengths and weakness, determining job-related knowledge and skills and identifying education and training needs appeared to be shared. Long-term responsibilities for developing individual careers and future development plans lay primarily with employees. New ways of managing nurses' career development that lead to greater independence for employees and greater flexibility for employers, while retaining a high-calibre and competent workforce, are needed. Ultimately, career management responsibilities should not tilt to either side but rather be shared to benefit both parties. Clarifying employers' and employees' responsibilities for career management may help both parties to develop a common understanding of each other's role and to meet their obligations in a constructive dialogue. © 2014 John Wiley & Sons Ltd.

  17. Wetland survey of selected areas in the K-24 Site Area of responsibility

    Energy Technology Data Exchange (ETDEWEB)

    Rosensteel, B.A.; Awl, D.J. [JAYCOR, Environmental Division, Oak Ridge, TN (United States)

    1995-07-01

    In accordance with DOE Regulations for Compliance with Floodplain/Wetlands Environmental Review Requirements, wetland surveys were conducted in selected areas within the K-25 Area of Responsibility during the summer of 1994. These areas are Mitchell Branch, Poplar Creek, the K-770 OU, Duct Island Peninsula, the Powerhouse area, and the K-25 South Corner. Previously surveyed areas included in this report are the main plant area of the K-25 Site, the K-901 OU, the AVLIS site, and the K-25 South Site. Wetland determinations were based on the USACE methodology. Forty-four separate wetland areas, ranging in size from 0.13 to 4.23 ha, were identified. Wetlands were identified in all of the areas surveyed with the exception of the interior of the Duct Island Peninsula and the main plant area of the K-25 Site. Wetlands perform functions such as floodflow alteration, sediment stabilization, sediment and toxicant retention, nutrient transformation, production export, and support of aquatic species and wildlife diversity and abundance. The forested, scrub-shrub, and emergent wetlands identified in the K-25 area perform some or all of these functions to varying degrees.

  18. Men's responses to HPV test results: development of a theory-based survey.

    Science.gov (United States)

    Daley, Ellen M; Buhi, Eric R; Baldwin, Julie; Lee, Ji-Hyun; Vadaparampil, Susan; Abrahamsen, Martha; Vamos, Cheryl A; Kolar, Stephanie; Chandler, Rasheeta; Anstey, Erica Hesch; Giuliano, Anna

    2009-01-01

    To develop and perform psychometric testing on an instrument designed to assess cognitive/emotional responses among men receiving HPV testing. Men enrolled in an HPV natural history study (N = 139) completed a computer-assisted survey instrument based on Leventhal's parallel processing/common-sense model. Data were analyzed using SPSS and Mplus. Reliability analyses resulted in Cronbach alpha of 0.72 (knowledge), 0.86 (perceived threat), 0.83 (self-efficacy), and 0.55 (response efficacy). A revised measurement model exhibited evidence of construct validity, as indicated by acceptable model fit statistics. To our knowledge, this is the only validated instrument assessing men's reactions to an HPV test result.

  19. Collecting substance use data with an anonymous mailed survey.

    Science.gov (United States)

    Trinkoff, A M; Storr, C L

    1997-10-25

    Because mailed surveys minimize personal contact, they are useful for collecting sensitive data on substance use, as long as the problems of achieving adequate response rates can be conquered. To address these issues, we report on an anonymous mailed survey of substance use with a 78% response rate, including data collection and survey methods. Analysis of sociodemographic effects on responding found certain groups required additional contacts. Substance use estimates were not affected by non-response bias, suggesting that anonymous mailed surveys can be a feasible means of collecting data on substance use.

  20. Responsibility for managing musculoskeletal disorders – A cross-sectional postal survey of attitudes

    Directory of Open Access Journals (Sweden)

    Larsson Maria EH

    2008-08-01

    Full Text Available Abstract Background Musculoskeletal disorders are a major burden on individuals, health systems and social care systems and rehabilitation efforts in these disorders are considerable. Self-care is often considered a cost effective treatment alternative owing to limited health care resources. But what are the expectations and attitudes in this question in the general population? The purpose of this study was to describe general attitudes to responsibility for the management of musculoskeletal disorders and to explore associations between attitudes and background variables. Methods A cross-sectional, postal questionnaire survey was carried out with a random sample of a general adult Swedish population of 1770 persons. Sixty-one percent (n = 1082 responded to the questionnaire and was included for the description of general attitudes towards responsibility for the management of musculoskeletal disorders. For the further analyses of associations to background variables 683–693 individuals could be included. Attitudes were measured by the "Attitudes regarding Responsibility for Musculoskeletal disorders" (ARM instrument, where responsibility is attributed on four dimensions; to myself, as being out of my hands, to employers or to (medical professionals. Multiple logistic regression was used to explore associations between attitudes to musculoskeletal disorders and the background variables age, sex, education, physical activity, presence of musculoskeletal disorders, sick leave and whether the person had visited a care provider. Results A majority of participants had internal views, i.e. showed an attitude of taking personal responsibility for musculoskeletal disorders, and did not place responsibility for the management out of their own hands or to employers. However, attributing shared responsibility between self and medical professionals was also found. The main associations found between attitude towards responsibility for musculoskeletal

  1. Survey Response Styles, Acculturation, and Culture Among a Sample of Mexican American Adults.

    Science.gov (United States)

    Davis, Rachel E; Resnicow, Ken; Couper, Mick P

    2011-10-01

    A number of studies have investigated use of extreme (ERS) and acquiescent (ARS) response styles across cultural groups. However, due to within-group heterogeneity, it is important to also examine use of response styles, acculturation, and endorsement of cultural variables at the individual level. This study explores relationships between acculturation, six Mexican cultural factors, ERS, and ARS among a sample of 288 Mexican American telephone survey respondents. Three aspects of acculturation were assessed: Spanish use, the importance of preserving Mexican culture, and interaction with Mexican Americans versus Anglos. These variables were hypothesized to positively associate with ERS and ARS. Participants with higher Spanish use did utilize more ERS and ARS; however, value for preserving Mexican culture and interaction with Mexican Americans were not associated with response style use. In analyses of cultural factors, endorsement of familismo and simpatia were related to more frequent ERS and ARS, machismo was associated with lower ERS among men, and la mujer was related to higher ERS among women. Caballerismo was marginally associated with utilization of ERS among men. No association was found between la mujer abnegada and ERS among women. Relationships between male gender roles and ARS were nonsignificant. Relationships between female gender roles and ARS were mixed but trended in the positive direction. Overall, these findings suggest that Mexican American respondents vary in their use of response styles by acculturation and cultural factors. This usage may be specifically influenced by participants' valuing of and engagement with constructs directly associated with social behavior.

  2. Behavioral Biases of Individual Investors: The Effect of Anchoring

    Directory of Open Access Journals (Sweden)

    Salma Zaiane

    2015-03-01

    Full Text Available The objective of this paper is to investigate the presence of the anchoring bias in the financial decision making of individual investors. A survey study is carried out to find out how the studied bias affects the investment behavior on the Tunisian stock market. The survey is for exploratory purpose and it is based on multiple factorial correspondence analyses. The results reveal that Tunisian investors do not suffer from the anchoring bias.

  3. Incentive and Reminder Strategies to Improve Response Rate for Internet-Based Physician Surveys: A Randomized Experiment

    Science.gov (United States)

    Wittich, Christopher M; Daniels, Wendlyn L; West, Colin P; Harris, Ann M; Beebe, Timothy J

    2016-01-01

    Background Most research on how to enhance response rates in physician surveys has been done using paper surveys. Uncertainties remain regarding how to enhance response rates in Internet-based surveys. Objective To evaluate the impact of a low-cost nonmonetary incentive and paper mail reminders (formal letter and postcard) on response rates in Internet-based physician surveys. Methods We executed a factorial-design randomized experiment while conducting a nationally representative Internet-based physician survey. We invited 3966 physicians (randomly selected from a commercial database of all licensed US physicians) via email to complete an Internet-based survey. We used 2 randomly assigned email messages: one message offered a book upon survey completion, whereas the other did not mention the book but was otherwise identical. All nonrespondents received several email reminders. Some physicians were further assigned at random to receive 1 reminder via paper mail (either a postcard or a letter) or no paper reminder. The primary outcome of this study was the survey response rate. Results Of the 3966 physicians who were invited, 451 (11.4%) responded to at least one survey question and 336 (8.5%) completed the entire survey. Of those who were offered a book, 345/2973 (11.6%) responded compared with 106/993 (10.7%) who were not offered a book (odds ratio 1.10, 95% CI 0.87-1.38, P=.42). Regarding the paper mail reminder, 168/1572 (10.7%) letter recipients, 148/1561 (9.5%) postcard recipients, and 69/767 (9.0%) email-only recipients responded (P=.35). The response rate for those receiving letters or postcards was similar (odds ratio 1.14, 95% CI 0.91-1.44, P=.26). Conclusions Offering a modest nonmonetary incentive and sending a paper reminder did not improve survey response rate. Further research on how to enhance response rates in Internet-based physician surveys is needed. PMID:27637296

  4. Framework for a U.S. Geological Survey Hydrologic Climate-Response Program in Maine

    Science.gov (United States)

    Hodgkins, Glenn A.; Lent, Robert M.; Dudley, Robert W.; Schalk, Charles W.

    2009-01-01

    This report presents a framework for a U.S. Geological Survey (USGS) hydrologic climate-response program designed to provide early warning of changes in the seasonal water cycle of Maine. Climate-related hydrologic changes on Maine's rivers and lakes in the winter and spring during the last century are well documented, and several river and lake variables have been shown to be sensitive to air-temperature changes. Monitoring of relevant hydrologic data would provide important baseline information against which future climate change can be measured. The framework of the hydrologic climate-response program presented here consists of four major parts: (1) identifying homogeneous climate-response regions; (2) identifying hydrologic components and key variables of those components that would be included in a hydrologic climate-response data network - as an example, streamflow has been identified as a primary component, with a key variable of streamflow being winter-spring streamflow timing; the data network would be created by maintaining existing USGS data-collection stations and establishing new ones to fill data gaps; (3) regularly updating historical trends of hydrologic data network variables; and (4) establishing basins for process-based studies. Components proposed for inclusion in the hydrologic climate-response data network have at least one key variable for which substantial historical data are available. The proposed components are streamflow, lake ice, river ice, snowpack, and groundwater. The proposed key variables of each component have extensive historical data at multiple sites and are expected to be responsive to climate change in the next few decades. These variables are also important for human water use and (or) ecosystem function. Maine would be divided into seven climate-response regions that follow major river-basin boundaries (basins subdivided to hydrologic units with 8-digit codes or larger) and have relatively homogeneous climates. Key

  5. There may not be a cultural life script for public events, but there is a youth bias: Response to Janssen (2014)

    DEFF Research Database (Denmark)

    Koppel, Jonathan Mark; Berntsen, Dorthe

    2015-01-01

    Janssen asserts that, in a recent paper, we introduced the concept of a cultural life script for public events, in the form of the youth bias. Moreover, he contends that we claimed to have found evidence for such a life script. Correspondingly, he frames his own failure to find evidence for a lif...

  6. Body mass index bias in defining obesity of diverse young adults: The Training Intervention and Genetics of Exercise Response (TIGER) Study

    Science.gov (United States)

    The BMI cut-score used to define overweight and obesity was derived primarily using data from Caucasian men and women. The present study evaluated the racial/ethnic bias of BMI to estimate the adiposity of young men and women (aged 17–35 years) using dual-energy X-ray absorptiometry (DXA) determinat...

  7. Measuring bias from unbiased observable

    CERN Document Server

    Lee, Seokcheon

    2014-01-01

    Since Kaiser introduced galaxies as a biased tracer of the underlying total mass field, the linear galaxies bias, b(z) appears ubiquitously both in theoretical calculations and in observational measurements related to galaxy surveys. However, the generic approaches to the galaxy density is a non-local and stochastic function of the underlying dark matter density and it becomes difficult to make the analytic form of b(z). Due to this fact, b(z) is known as a nuisance parameter and the effort has been made to measure bias free observable quantities. We provide the exact and analytic function of b(z) which also can be measured from galaxy surveys using the redshift space distortions parameters, more accurately unbiased observable \\beta \\sigma_{\\rm{gal}} = f \\sigma_8. We also introduce approximate solutions for b(z) for different gravity theories. One can generalize these approximate solutions to be exact when one solves the exact evolutions for the dark matter density fluctuation of given gravity theories. These...

  8. Removing Malmquist bias from linear regressions

    Science.gov (United States)

    Verter, Frances

    1993-01-01

    Malmquist bias is present in all astronomical surveys where sources are observed above an apparent brightness threshold. Those sources which can be detected at progressively larger distances are progressively more limited to the intrinsically luminous portion of the true distribution. This bias does not distort any of the measurements, but distorts the sample composition. We have developed the first treatment to correct for Malmquist bias in linear regressions of astronomical data. A demonstration of the corrected linear regression that is computed in four steps is presented.

  9. Socially responsible ethnobotanical surveys in the Cape Floristic Region: ethical principles, methodology and quantification of data

    Directory of Open Access Journals (Sweden)

    Ben-Erik Van Wyk

    2012-03-01

    Full Text Available A broad overview of published and unpublished ethnobotanical surveys in the Cape Floristic Region (the traditional home of the San and Khoi communities shows that the data is incomplete. There is an urgent need to record the rich indigenous knowledge about plants in a systematic and social responsible manner in order to preserve this cultural and scientific heritage for future generations. Improved methods for quantifying data are introduced, with special reference to the simplicity and benefits of the new Matrix Method. This methodology prevents or reduces the number of false negatives, and also ensures the participation of elderly people who might be immobile. It also makes it possible to compare plant uses in different local communities. This method enables the researcher to quantify the knowledge on plant use that was preserved in a community, and to determine the relative importance of a specific plant in a more objective way. Ethical considerations for such ethnobotanical surveys are discussed, through the lens of current ethical codes and international conventions. This is an accessible approach, which can also be used in the life sciences classroom.

  10. Efficient Consumer Response (ECR: a survey of the Australian grocery industry

    Directory of Open Access Journals (Sweden)

    Paula Swatman

    1998-05-01

    Full Text Available Efficient consumer response (ECR is a U.S. supply chain management strategy which attempts to address the inefficiencies which have led to excessive inventory and unnecessary costs at all levels within the grocery industry supply chain. This paper discusses the traditional grocery store format, the supermarket, and the ways in which inefficient business practices developed in the U.S. grocery supply chain; and discusses the major business activities needed for successful implementation of ECR. The paper then presents a brief summary of the results of a survey of ECR knowledge and usage within the Australian grocery industry, which is the initial phase of a long term research project whose main purpose is to evaluate ECR as it applies to that industry.

  11. Bright and Faint Ends of Ly$\\alpha$ Luminosity Functions at $\\textit{z} = 2$ Determined by the Subaru Survey: Implications for AGN, Magnification Bias, and ISM HI Evolution

    CERN Document Server

    Konno, Akira; Nakajima, Kimihiko; Duval, Florent; Kusakabe, Haruka; Ono, Yoshiaki; Shimasaku, Kazuhiro

    2015-01-01

    We present the Lya luminosity functions (LFs) derived by our deep Subaru narrowband survey that identifies a total of 3,137 Lya emitters (LAEs) at $z = 2.2$ in five independent blank fields. The sample of these LAEs is the largest, to date, and covers a very wide Lya luminosity range of $\\log L_{Ly\\alpha} = 41.7-44.4$ erg s$^{-1}$. We determine the Lya LF at $z = 2.2$ with unprecedented accuracies, and obtain the best-fit Schechter parameters of $L^{*}_{Ly\\alpha} = 5.29^{+1.67}_{-1.13} \\times 10^{42}$ erg s$^{-1}$, $\\phi^{*}_{Ly\\alpha} = 6.32^{+3.08}_{-2.31} \\times 10^{-4}$ Mpc$^{-3}$, and $\\alpha = -1.75^{+0.10}_{-0.09}$ showing a steep faint-end slope. We identify a significant hump at the LF bright end ($\\log L_{Ly\\alpha} > 43.4$ erg s$^{-1}$). Because all of the LAEs in the bright-end hump have (a) bright counterpart(s) either in the X-ray, UV, or radio data, this bright-end hump is not made by gravitational lensing magnification bias but AGNs. These AGNs allow us to derive the AGN UV LF at $z \\sim 2$ dow...

  12. Strategies for achieving a high response rate in a home interview survey

    Directory of Open Access Journals (Sweden)

    Power Kevin

    2009-06-01

    Full Text Available Abstract Background Response rates in surveys have been falling over the last 20 years, leading to the need for novel approaches to enhance recruitment. This study describes strategies used to maximise recruitment to a home interview survey of mothers with young children living in areas of high deprivation. Methods Mothers of two year old children received a letter from their GP inviting them to take part in a survey on diet. Participants were subsequently recruited by a researcher. The researcher first tried to contact potential participants by telephone, to discuss the study and make an appointment to conduct a home interview. Where telephone numbers for women could not be obtained from GP records, web searches of publicly available databases were conducted. After obtaining correct telephone numbers, up to six attempts were made to establish contact by telephone. If this was unsuccessful, a postal request for telephone contact was made. Where no telephone contact was achieved, the researcher sent up to two appointments by post to conduct a home interview. Results Participating GPs invited 372 women to take part in a home based interview study. GP practices provided telephone numbers for 162 women, of which 134 were valid numbers. The researcher identified a further 187 numbers from electronic directories. Further searches of GP records by practice staff yielded another 38 telephone numbers. Thus, telephone numbers were obtained for 99% of potential participants. The recruitment rate from telephone contacts was 77%. Most of the gain was achieved within four calls. For the remaining women, contact by post and home visits resulted in 18 further interviews, corresponding to 35% of the women not recruited by telephone. The final interview rate was 82%. This was possible because personal contact was established with 95% of potential participants. Conclusion This study achieved a high response rate in a hard to reach group. This was mainly achieved

  13. Factors influencing identification of and response to intimate partner violence: a survey of physicians and nurses

    Directory of Open Access Journals (Sweden)

    Wathen C Nadine

    2007-01-01

    Full Text Available Abstract Background Intimate partner violence against women (IPV has been identified as a serious public health problem. Although the health care system is an important site for identification and intervention, there have been challenges in determining how health care professionals can best address this issue in practice. We surveyed nurses and physicians in 2004 regarding their attitudes and behaviours with respect to IPV, including whether they routinely inquire about IPV, as well as potentially relevant barriers, facilitators, experiential, and practice-related factors. Methods A modified Dillman Tailored Design approach was used to survey 1000 nurses and 1000 physicians by mail in Ontario, Canada. Respondents were randomly selected from professional directories and represented practice areas pre-identified from the literature as those most likely to care for women at the point of initial IPV disclosure: family practice, obstetrics and gynecology, emergency care, maternal/newborn care, and public health. The survey instrument had a case-based scenario followed by 43 questions asking about behaviours and resources specific to woman abuse. Results In total, 931 questionnaires were returned; 597 by nurses (59.7% response rate and 328 by physicians (32.8% response rate. Overall, 32% of nurses and 42% of physicians reported routinely initiating the topic of IPV in practice. Principal components analysis identified eight constructs related to whether routine inquiry was conducted: preparedness, self-confidence, professional supports, abuse inquiry, practitioner consequences of asking, comfort following disclosure, practitioner lack of control, and practice pressures. Each construct was analyzed according to a number of related issues, including clinician training and experience with woman abuse, area of practice, and type of health care provider. Preparedness emerged as a key construct related to whether respondents routinely initiated the topic of

  14. A nonparametric approach to the sample selection problem in survey data

    NARCIS (Netherlands)

    Vazquez-Alvarez, R.

    2001-01-01

    Responses to economic surveys are usually noisy. Item non-response, as a particular type of censored data, is a common problem for key economic variables such as income and earnings, consumption or accumulated assets. If such non-response is non-random, the consequence can be a bias in the results o

  15. CPI Bias in Korea

    Directory of Open Access Journals (Sweden)

    Chul Chung

    2007-12-01

    Full Text Available We estimate the CPI bias in Korea by employing the approach of Engel’s Law as suggested by Hamilton (2001. This paper is the first attempt to estimate the bias using Korean panel data, Korean Labor and Income Panel Study(KLIPS. Following Hamilton’s model with non­linear specification correction, our estimation result shows that the cumulative CPI bias over the sample period (2000-2005 was 0.7 percent annually. This CPI bias implies that about 21 percent of the inflation rate during the period can be attributed to the bias. In light of purchasing power parity, we provide an interpretation of the estimated bias.

  16. Prophylactic Platelets in Dengue: Survey Responses Highlight Lack of an Evidence Base

    Science.gov (United States)

    Whitehorn, James; Roche, Rosmari Rodriguez; Guzman, Maria G.; Martinez, Eric; Villamil Gomez, Wilmar; Nainggolan, Leonard; Laksono, Ida Safitri; Mishra, Ajay; Lum, Lucy; Faiz, Abul; Sall, Amadou; Dawurung, Joshua; Borges, Alvaro; Leo, Yee-Sin; Blumberg, Lucille; Bausch, Daniel G.; Kroeger, Axel; Horstick, Olaf; Thwaites, Guy; Wertheim, Heiman; Larsson, Mattias; Hien, Tran Tinh; Peeling, Rosanna; Wills, Bridget; Simmons, Cameron; Farrar, Jeremy

    2012-01-01

    Dengue is the most important arboviral infection of humans. Thrombocytopenia is frequently observed in the course of infection and haemorrhage may occur in severe disease. The degree of thrombocytopenia correlates with the severity of infection, and may contribute to the risk of haemorrhage. As a result of this prophylactic platelet transfusions are sometimes advocated for the prevention of haemorrhage. There is currently no evidence to support this practice, and platelet transfusions are costly and sometimes harmful. We conducted a global survey to assess the different approaches to the use of platelets in dengue. Respondents were all physicians involved with the treatment of patients with dengue. Respondents were asked that their answers reflected what they would do if they were the treating physician. We received responses from 306 physicians from 20 different countries. The heterogeneity of the responses highlights the variation in clinical practice and lack of an evidence base in this area and underscores the importance of prospective clinical trials to address this key question in the clinical management of patients with dengue. PMID:22745847

  17. Prophylactic platelets in dengue: survey responses highlight lack of an evidence base.

    Directory of Open Access Journals (Sweden)

    James Whitehorn

    Full Text Available Dengue is the most important arboviral infection of humans. Thrombocytopenia is frequently observed in the course of infection and haemorrhage may occur in severe disease. The degree of thrombocytopenia correlates with the severity of infection, and may contribute to the risk of haemorrhage. As a result of this prophylactic platelet transfusions are sometimes advocated for the prevention of haemorrhage. There is currently no evidence to support this practice, and platelet transfusions are costly and sometimes harmful. We conducted a global survey to assess the different approaches to the use of platelets in dengue. Respondents were all physicians involved with the treatment of patients with dengue. Respondents were asked that their answers reflected what they would do if they were the treating physician. We received responses from 306 physicians from 20 different countries. The heterogeneity of the responses highlights the variation in clinical practice and lack of an evidence base in this area and underscores the importance of prospective clinical trials to address this key question in the clinical management of patients with dengue.

  18. Reliability, validity and responsiveness of a Norwegian version of the Chronic Sinusitis Survey

    Directory of Open Access Journals (Sweden)

    Røssberg Edna

    2006-05-01

    Full Text Available Abstract Background The Chronic Sinusitis Survey (CSS is a valid, disease-specific questionnaire for assessing health status and treatment effectiveness in chronic rhinosinusitis. In the present study, we developed a Norwegian version of the CSS and assessed its psychometric properties. Methods In the pooled data set of 65 patients from a trial of treatment for chronic sinusitis with long-standing symptoms and signs of sinusitis on computed tomography (CT, we assessed the reliability, validity and responsiveness of the CSS. Results Test-retest reliability of the two CSS scales and the total scale ranged 0.87–0.92, while internal consistency reliability ranged 0.31–0.55. CSS subscale scores were associated with other items on sinusitis symptoms, and with the Mental health and Bodily pain scale of the SF-36. There was little association of the CSS scale scores with sinus CT findings. The patients with chronic sinusitis had worse scores on all three CSS scales than a healthy reference population (n = 42 (p Conclusion The Norwegian version of the CSS had acceptable test-retest reliability, but lower internal consistency reliability than the accepted standard criteria. The results support the construct validity of the measure and the sinusitis symptoms subscale and the total scales were responsive to change. This supports the use of the questionnaire in interventions for chronic sinusitis, but points at problems with the internal consistency reliability.

  19. On commercial media bias

    OpenAIRE

    Germano, Fabrizio

    2008-01-01

    Within the spokes model of Chen and Riordan (2007) that allows for non-localized competition among arbitrary numbers of media outlets, we quantify the effect of concentration of ownership on quality and bias of media content. A main result shows that too few commercial outlets, or better, too few separate owners of commercial outlets can lead to substantial bias in equilibrium. Increasing the number of outlets (commercial and non-commercial) tends to bring down this bias; but the strongest ef...

  20. The response of future projections of the North American monsoon when combining dynamical downscaling and bias correction of CCSM4 output

    Science.gov (United States)

    Meyer, Jonathan D. D.; Jin, Jiming

    2016-09-01

    A 20-km regional climate model (RCM) dynamically downscaled the Community Climate System Model version 4 (CCSM4) to compare 32-year historical and future "end-of-the-century" climatologies of the North American Monsoon (NAM). CCSM4 and other phase 5 Coupled Model Intercomparison Project models have indicated a delayed NAM and overall general drying trend. Here, we test the suggested mechanism for this drier NAM where increasing atmospheric static stability and reduced early-season evapotranspiration under global warming will limit early-season convection and compress the mature-season of the NAM. Through our higher resolution RCM, we found the role of accelerated evaporation under a warmer climate is likely understated in coarse resolution models such as CCSM4. Improving the representation of mesoscale interactions associated with the Gulf of California and surrounding topography produced additional surface evaporation, which overwhelmed the convection-suppressing effects of a warmer troposphere. Furthermore, the improved land-sea temperature gradient helped drive stronger southerly winds and greater moisture transport. Finally, we addressed limitations from inherent CCSM4 biases through a form of mean bias correction, which resulted in a more accurate seasonality of the atmospheric thermodynamic profile. After bias correction, greater surface evaporation from average peak GoC SSTs of 32 °C compared to 29 °C from the original CCSM4 led to roughly 50 % larger changes to low-level moist static energy compared to that produced by the downscaled original CCSM4. The increasing destabilization of the NAM environment produced onset dates that were one to 2 weeks earlier in the core of the NAM and northern extent, respectively. Furthermore, a significantly more vigorous NAM signal was produced after bias correction, with >50 mm month-1 increases to the June-September precipitation found along east and west coasts of Mexico and into parts of Texas. A shift towards more

  1. Interpretation biases in paranoia.

    Science.gov (United States)

    Savulich, George; Freeman, Daniel; Shergill, Sukhi; Yiend, Jenny

    2015-01-01

    Information in the environment is frequently ambiguous in meaning. Emotional ambiguity, such as the stare of a stranger, or the scream of a child, encompasses possible good or bad emotional consequences. Those with elevated vulnerability to affective disorders tend to interpret such material more negatively than those without, a phenomenon known as "negative interpretation bias." In this study we examined the relationship between vulnerability to psychosis, measured by trait paranoia, and interpretation bias. One set of material permitted broadly positive/negative (valenced) interpretations, while another allowed more or less paranoid interpretations, allowing us to also investigate the content specificity of interpretation biases associated with paranoia. Regression analyses (n=70) revealed that trait paranoia, trait anxiety, and cognitive inflexibility predicted paranoid interpretation bias, whereas trait anxiety and cognitive inflexibility predicted negative interpretation bias. In a group comparison those with high levels of trait paranoia were negatively biased in their interpretations of ambiguous information relative to those with low trait paranoia, and this effect was most pronounced for material directly related to paranoid concerns. Together these data suggest that a negative interpretation bias occurs in those with elevated vulnerability to paranoia, and that this bias may be strongest for material matching paranoid beliefs. We conclude that content-specific biases may be important in the cause and maintenance of paranoid symptoms.

  2. Do postage stamps versus pre-paid envelopes increase responses to patient mail surveys? A randomised controlled trial

    Directory of Open Access Journals (Sweden)

    Campbell Malcolm

    2008-05-01

    Full Text Available Abstract Background Studies largely from the market research field suggest that the inclusion of a stamped addressed envelope, rather than a pre-paid business reply, increases the response rate to mail surveys. The evidence that this is also the case regarding patient mail surveys is limited. Methods The aim of this study is to investigate whether stamped addressed envelopes increase response rates to patient mail surveys compared to pre-paid business reply envelopes and compare the relative costs. A sample of 477 initial non-responders to a mail survey of patients attending breast clinics in Greater Manchester between 1/10/2002 – 31/7/2003 were entered into the trial: 239 were randomly allocated to receive a stamped envelope and 238 to receive a pre-paid envelope in with their reminder surveys. Overall cost and per item returned were calculated. Results The response to the stamped envelope group was 31.8% (95% CI: 25.9% – 37.7% compared to 26.9% (21.3% – 32.5% for the pre-paid group. The difference (4.9% 95% CI: -3.3% – 13.1% is not significant at α = 0.05 (χ2 = 1.39; 2 tailed test, d.f. = 1; P = 0.239. The stamped envelopes were cheaper in terms of cost per returned item (£1.20 than the pre-paid envelopes (£1.67. However if the set up cost for the licence to use the pre-paid service is excluded, the cost of the stamped envelopes is more expensive than pre-paid returns (£1.20 versus £0.73. Conclusion Compared with pre-paid business replies, stamped envelopes did not produce a statistically significant increase in response rate to this patient survey. However, the response gain of the stamped strategy (4.9% is similar to that demonstrated in a Cochrane review (5.3% of strategies to increase response to general mail surveys. Further studies and meta analyses of patient responses to mail surveys via stamped versus pre-paid envelopes are needed with sufficient power to detect response gains of this magnitude in a patient population.

  3. Ratio Bias and Policy Preferences

    DEFF Research Database (Denmark)

    Pedersen, Rasmus Tue

    2016-01-01

    Numbers permeate modern political communication. While current scholarship on framing effects has focused on the persuasive effects of words and arguments, this article shows that framing of numbers can also substantially affect policy preferences. Such effects are caused by ratio bias, which...... is a general tendency to focus on numerators and pay insufficient attention to denominators in ratios. Using a population-based survey experiment, I demonstrate how differently framed but logically equivalent representations of the exact same numerical value can have large effects on citizens’ preferences...

  4. Adult responses to a survey of soil contact-related behaviors.

    Science.gov (United States)

    Garlock, T J; Shirai, J H; Kissel, J C

    1999-01-01

    Protocols used to assess human exposure to chemicals in soils at contaminated sites often include a dermal pathway. Use of default parameters to assess dermal exposure to soil can easily lead to risk projections that appear to warrant remedial action. However, because those default parameters are typically highly uncertain, risk estimates based upon them inspire little confidence. To better characterize assumptions regarding dermal exposures, a telephone survey instrument was developed to elicit information on behaviors relevant to assessment of dermal contact with soil and dust. Participation in four activities--gardening, other yard work, outdoor team sports, and home construction or repair involving digging--was investigated. Questions were also asked regarding clothing choices and post-activity bathing practices. The survey was administered to two populations of approximately 450 adult respondents each using random digit dialing. The first was a national (U.S.) sample. The second sample was drawn from counties surrounding the Hanford Nuclear Reservation. Seventy-nine percent of the regional respondents and 89% of the national respondents reported participating in at least one of the four targeted activities. Responses of doers regarding clothing choices suggest that median fractions of skin exposed during warm-weather activities typically exceed the 25% often assumed. The Hanford sample differed from the national sample in the fraction residing in single-family homes, the fraction describing their residential surroundings as rural, and in ethnic makeup. The Hanford population displayed greater rates of participation than the national sample in three activities that have an obvious link to residence in a single-family dwelling: home repair involving digging, gardening, and other yard work, but differences were not explained entirely by residence type. The regional population also reported greater frequency of participation in multiple activities. In contrast

  5. Understanding barriers to medication adherence in the hypertensive population by evaluating responses to a telephone survey

    Directory of Open Access Journals (Sweden)

    Nair KV

    2011-04-01

    Full Text Available Kavita V Nair1, Daniel A Belletti3, Joseph J Doyle3, Richard R Allen4, Robert B McQueen1, Joseph J Saseen1, Joseph Vande Griend1, Jay V Patel5, Angela McQueen2, Saira Jan21School of Pharmacy, University of Colorado, Aurora, CO, USA; 2Horizon Blue Cross Blue Shield of New Jersey, Newark, NJ, USA; 3Novartis Pharmaceuticals Corporation, East Hanover, NJ, USA, 4Peakstat Statistical Services, Evergreen, CO, USA; 5Care Management International, Marlborough, MA, USABackground: Although hypertension is a major risk factor for cardiovascular disease, adherence to hypertensive medications is low. Previous research identifying factors influencing adherence has focused primarily on broad, population-based approaches. Identifying specific barriers for an individual is more useful in designing meaningful targeted interventions. Using customized telephonic outreach, we examined specific patient-reported barriers influencing hypertensive patients' nonadherence to medication in order to identify targeted interventions.Methods: A telephone survey of 8692 nonadherent hypertensive patients was conducted. The patient sample comprised health plan members with at least two prescriptions for antihypertensive medications in 2008. The telephone script was based on the "target" drug associated with greatest nonadherence (medication possession ratio [MPR] <80% during the four-month period preceding the survey.Results: The response rate was 28.2% of the total sample, representing 63.8% of commercial members and 37.2% of Medicare members. Mean age was 63.4 years. Mean MPR was 61.0% for the target drug. Only 58.2% of Medicare respondents and 60.4% of commercial respondents reported "missing a dose of medication". The primary reason given was "forgetfulness" (61.8% Medicare, 60.8% commercial, followed by "being too busy" (2.7% Medicare, 18.5% commercial and "other reasons" (21.9% Medicare, 8.1% commercial including travel, hospitalization/sickness, disruption of daily events

  6. The Success of a Planned Bereavement Response--A Survey on Teacher Use of Bereavement Response Plans When Supporting Grieving Children in Danish Schools

    Science.gov (United States)

    Lytje, Martin

    2017-01-01

    This article investigates the strengths and weaknesses of the Danish Bereavement response plans. These are used by teachers to support grieving students and have been implemented in 96% of all Danish schools. The study is based on an Internet survey conducted with 967 teachers. Issues investigated are: "generalisation of grief",…

  7. Political bias is tenacious.

    Science.gov (United States)

    Ditto, Peter H; Wojcik, Sean P; Chen, Eric Evan; Grady, Rebecca Hofstein; Ringel, Megan M

    2015-01-01

    Duarte et al. are right to worry about political bias in social psychology but they underestimate the ease of correcting it. Both liberals and conservatives show partisan bias that often worsens with cognitive sophistication. More non-liberals in social psychology is unlikely to speed our convergence upon the truth, although it may broaden the questions we ask and the data we collect.

  8. Biases in categorization

    NARCIS (Netherlands)

    Das-Smaal, E.A.

    1990-01-01

    On what grounds can we conclude that an act of categorization is biased? In this chapter, it is contended that in the absence of objective norms of what categories actually are, biases in categorization can only be specified in relation to theoretical understandings of categorization. Therefore, the

  9. Reducing hypothetical bias in choice experiments

    DEFF Research Database (Denmark)

    Ladenburg, Jacob; Olsen, Søren Bøye; Nielsen, Rasmus Christian Fejer

    Hypothetical bias in stated preference studies is an essential problem which reduces the validity of the obtained welfare estimates for non-market goods. In the attempt to mitigate hypothetical bias, a type of reminder known as Cheap Talk, has been applied in previous studies and found to overall...... eliminate some of the hypothetical bias. The present paper tests an addition to Cheap Talk, an Opt-Out Reminder. The Opt-Out Reminder is an objective short script presented prior to the choice sets, prompting the respondent to choose the opt-out alternative, if he/she finds the proposed policy generated...... alternatives in a choice set too expensive. The results suggest that adding an Opt-Out Reminder to Cheap Talk can in fact reduce hypothetical bias even further and reduces some of the ineffectiveness of CT in relation to the survey bid range and experienced respondents....

  10. Adaptive Variable Bias Magnetic Bearing Control

    Science.gov (United States)

    Johnson, Dexter; Brown, Gerald V.; Inman, Daniel J.

    1998-01-01

    Most magnetic bearing control schemes use a bias current with a superimposed control current to linearize the relationship between the control current and the force it delivers. With the existence of the bias current, even in no load conditions, there is always some power consumption. In aerospace applications, power consumption becomes an important concern. In response to this concern, an alternative magnetic bearing control method, called Adaptive Variable Bias Control (AVBC), has been developed and its performance examined. The AVBC operates primarily as a proportional-derivative controller with a relatively slow, bias current dependent, time-varying gain. The AVBC is shown to reduce electrical power loss, be nominally stable, and provide control performance similar to conventional bias control. Analytical, computer simulation, and experimental results are presented in this paper.

  11. Implementing medical revalidation in the United Kingdom: Findings about organisational changes and impacts from a survey of Responsible Officers

    Science.gov (United States)

    Boyd, Alan; Bryce, Marie; Luscombe, Kayleigh; Tazzyman, Abigail; Tredinnick-Rowe, John; Archer, Julian

    2017-01-01

    Objective To describe the implementation of medical revalidation in healthcare organisations in the United Kingdom and to examine reported changes and impacts on the quality of care. Design A cross-sectional online survey gathering both quantitative and qualitative data about structures and processes for medical revalidation and wider quality management in the organisations which employ or contract with doctors (termed ‘designated bodies’) from the senior doctor in each organisation with statutory responsibility for medical revalidation (termed the ‘Responsible Officer’). Setting United Kingdom Participants Responsible Officers in designated bodies in the United Kingdom. Five hundred and ninety-five survey invitations were sent and 374 completed surveys were returned (63%). Main outcome measures The role of Responsible Officers, the development of organisational mechanisms for quality assurance or improvement, decision-making on revalidation recommendations, impact of revalidation and mechanisms for quality assurance or improvement on clinical practice and suggested improvements to revalidation arrangements. Results Responsible Officers report that revalidation has had some impacts on the way medical performance is assured and improved, particularly strengthening appraisal and oversight of quality within organisations and having some impact on clinical practice. They suggest changes to make revalidation less ‘one size fits all’ and more responsive to individual, organisational and professional contexts. Conclusions Revalidation appears primarily to have improved systems for quality improvement and the management of poor performance to date. There is more to be done to ensure it produces wider benefits, particularly in relation to doctors who already perform well. PMID:28084166

  12. The Rapid Response Radiation Survey (R3S) Mission Using the HISat Conformal Satellite Architecture

    Science.gov (United States)

    Miller, Nathanael

    2015-01-01

    The Rapid Response Radiation Survey (R3S) experiment, designed as a quick turnaround mission to make radiation measurements in LEO, will fly as a hosted payload in partnership with NovaWurks using their Hyper-integrated Satlet (HiSat) architecture. The need for the mission arises as the Nowcast of Atmospheric Ionization Radiation for Aviation Safety (NAIRAS) model moves from a research effort into an operational radiation assessment tool. The data collected by R3S, in addition to the complementary data from a NASA Langley Research Center (LaRC) atmospheric balloon mission entitled Radiation Dosimetry Experiment (RaDX), will validate exposure prediction capabilities of NAIRAS. This paper discusses the development of the R3S experiment as made possible by use of the HiSat architecture. The system design and operational modes of the experiment are described, as well as the experiment interfaces to the HiSat satellite via the user defined adapter (UDA) provided by NovaWurks. This paper outlines the steps taken by the project to execute the R3S mission in the 4 months of design, build, and test. Finally, description of the engineering process is provided, including the use of facilitated rapid/concurrent engineering sessions, the associated documentation, and the review process employed.

  13. Developing Culturally Responsive Surveys: Lessons in Development, Implementation, and Analysis from Brazil's African Descent Communities

    Science.gov (United States)

    Bowen, Merle L.; Tillman, Ayesha S.

    2015-01-01

    Considerable empirical research, along with a growing body of conceptual and theoretical literature, exists on the role of culture and context in evaluation. Less scholarship has examined culturally responsive surveys in the context of international evaluation. In this article, the authors present lessons learned from the development,…

  14. Mechanistic insight into the TH1-biased immune response to recombinant subunit vaccines delivered by probiotic bacteria-derived outer membrane vesicles.

    Science.gov (United States)

    Rosenthal, Joseph A; Huang, Chung-Jr; Doody, Anne M; Leung, Tiffany; Mineta, Kaho; Feng, Danielle D; Wayne, Elizabeth C; Nishimura, Nozomi; Leifer, Cynthia; DeLisa, Matthew P; Mendez, Susana; Putnam, David

    2014-01-01

    Recombinant subunit vaccine engineering increasingly focuses on the development of more effective delivery platforms. However, current recombinant vaccines fail to sufficiently stimulate protective adaptive immunity against a wide range of pathogens while remaining a cost effective solution to global health challenges. Taking an unorthodox approach to this fundamental immunological challenge, we isolated the TLR-targeting capability of the probiotic E. coli Nissle 1917 bacteria (EcN) by engineering bionanoparticlate antigen carriers derived from EcN outer membrane vesicles (OMVs). Exogenous model antigens expressed by these modified bacteria as protein fusions with the bacterial enterotoxin ClyA resulted in their display on the surface of the carrier OMVs. Vaccination with the engineered EcN OMVs in a BALB/c mouse model, and subsequent mechanism of action analysis, established the EcN OMV's ability to induce self-adjuvanted robust and protective humoral and T(H)1-biased cellular immunity to model antigens. This finding appears to be strain-dependent, as OMV antigen carriers similarly engineered from a standard K12 E. coli strain derivative failed to generate a comparably robust antigen-specific TH1 bias. The results demonstrate that unlike traditional subunit vaccines, these biomolecularly engineered "pathogen-like particles" derived from traditionally overlooked, naturally potent immunomodulators have the potential to effectively couple recombinant antigens with meaningful immunity in a broadly applicable fashion.

  15. Mechanistic insight into the TH1-biased immune response to recombinant subunit vaccines delivered by probiotic bacteria-derived outer membrane vesicles.

    Directory of Open Access Journals (Sweden)

    Joseph A Rosenthal

    Full Text Available Recombinant subunit vaccine engineering increasingly focuses on the development of more effective delivery platforms. However, current recombinant vaccines fail to sufficiently stimulate protective adaptive immunity against a wide range of pathogens while remaining a cost effective solution to global health challenges. Taking an unorthodox approach to this fundamental immunological challenge, we isolated the TLR-targeting capability of the probiotic E. coli Nissle 1917 bacteria (EcN by engineering bionanoparticlate antigen carriers derived from EcN outer membrane vesicles (OMVs. Exogenous model antigens expressed by these modified bacteria as protein fusions with the bacterial enterotoxin ClyA resulted in their display on the surface of the carrier OMVs. Vaccination with the engineered EcN OMVs in a BALB/c mouse model, and subsequent mechanism of action analysis, established the EcN OMV's ability to induce self-adjuvanted robust and protective humoral and T(H1-biased cellular immunity to model antigens. This finding appears to be strain-dependent, as OMV antigen carriers similarly engineered from a standard K12 E. coli strain derivative failed to generate a comparably robust antigen-specific TH1 bias. The results demonstrate that unlike traditional subunit vaccines, these biomolecularly engineered "pathogen-like particles" derived from traditionally overlooked, naturally potent immunomodulators have the potential to effectively couple recombinant antigens with meaningful immunity in a broadly applicable fashion.

  16. Comparison of response patterns in different survey designs: a longitudinal panel with mixed-mode and online-only design.

    Science.gov (United States)

    Rübsamen, Nicole; Akmatov, Manas K; Castell, Stefanie; Karch, André; Mikolajczyk, Rafael T

    2017-01-01

    Increasing availability of the Internet allows using only online data collection for more epidemiological studies. We compare response patterns in a population-based health survey using two survey designs: mixed-mode (choice between paper-and-pencil and online questionnaires) and online-only design (without choice). We used data from a longitudinal panel, the Hygiene and Behaviour Infectious Diseases Study (HaBIDS), conducted in 2014/2015 in four regions in Lower Saxony, Germany. Individuals were recruited using address-based probability sampling. In two regions, individuals could choose between paper-and-pencil and online questionnaires. In the other two regions, individuals were offered online-only participation. We compared sociodemographic characteristics of respondents who filled in all panel questionnaires between the mixed-mode group (n = 1110) and the online-only group (n = 482). Using 134 items, we performed multinomial logistic regression to compare responses between survey designs in terms of type (missing, "do not know" or valid response) and ordinal regression to compare responses in terms of content. We applied the false discovery rates (FDR) to control for multiple testing and investigated effects of adjusting for sociodemographic characteristic. For validation of the differential response patterns between mixed-mode and online-only, we compared the response patterns between paper and online mode among the respondents in the mixed-mode group in one region (n = 786). Respondents in the online-only group were older than those in the mixed-mode group, but both groups did not differ regarding sex or education. Type of response did not differ between the online-only and the mixed-mode group. Survey design was associated with different content of response in 18 of the 134 investigated items; which decreased to 11 after adjusting for sociodemographic variables. In the validation within the mixed-mode, only two of those were among the 11 significantly

  17. Size bias for one and all

    OpenAIRE

    Arratia, Richard; Goldstein, Larry; Kochman, Fred

    2013-01-01

    Size bias occurs famously in waiting-time paradoxes, undesirably in sampling schemes, and unexpectedly in connection with Stein's method, tightness, analysis of the lognormal distribution, Skorohod embedding, infinite divisibility, and number theory. In this paper we review the basics and survey some of these unexpected connections.

  18. Media Bias and Reputation

    OpenAIRE

    Matthew Gentzkow; Jesse M. Shapiro

    2005-01-01

    A Bayesian consumer who is uncertain about the quality of an information source will infer that the source is of higher quality when its reports conform to the consumer's prior expectations. We use this fact to build a model of media bias in which firms slant their reports toward the prior beliefs of their customers in order to build a reputation for quality. Bias emerges in our model even though it can make all market participants worse off. The model predicts that bias will be less severe w...

  19. Biased predecision processing.

    Science.gov (United States)

    Brownstein, Aaron L

    2003-07-01

    Decision makers conduct biased predecision processing when they restructure their mental representation of the decision environment to favor one alternative before making their choice. The question of whether biased predecision processing occurs has been controversial since L. Festinger (1957) maintained that it does not occur. The author reviews relevant research in sections on theories of cognitive dissonance, decision conflict, choice certainty, action control, action phases, dominance structuring, differentiation and consolidation, constructive processing, motivated reasoning, and groupthink. Some studies did not find evidence of biased predecision processing, but many did. In the Discussion section, the moderators are summarized and used to assess the theories.

  20. Berkson’s bias, selection bias, and missing data

    OpenAIRE

    Westreich, Daniel

    2012-01-01

    While Berkson’s bias is widely recognized in the epidemiologic literature, it remains underappreciated as a model of both selection bias and bias due to missing data. Simple causal diagrams and 2×2 tables illustrate how Berkson’s bias connects to collider bias and selection bias more generally, and show the strong analogies between Berksonian selection bias and bias due to missing data. In some situations, considerations of whether data are missing at random or missing not at random is less i...

  1. Publishers' Responses to the E-Book Phenomenon: Survey Results from Three "Small Language" Markets

    Science.gov (United States)

    Wilson, T. D.; Maceviciute, Elena

    2016-01-01

    Introduction: This paper reports on a study of publishers' attitudes towards e-books in the context of the global situation of e-book publishing. Comparative data are drawn from a replication of a survey carried out in Sweden, in Lithuania and in Croatia. Method: A self-completed questionnaire survey was undertaken, offering respondents the choice…

  2. A study on investors’ personality characteristics and behavioral biases: Conservatism bias and availability bias in the Tehran Stock Exchange

    Directory of Open Access Journals (Sweden)

    Mahmoud Moradi

    2013-04-01

    Full Text Available Most economic and finance theories are based on the assumption that during economic decision making, people would act totally rational and consider all available information. Nevertheless, behavioral finance focuses on studying of the role of psychological factors on economic participants’ behavior. The study shows that in real-world environment, people are influenced by emotional and cognitive errors and may make irrational financial decisions. In many cases, the participants of financial markets are not aware of their talents for error in decision making, so they are dissatisfied with their investments by considering some behavioral biases decisions. These decisions may often yield undesirable outcomes, which could influence economy, significantly. This paper presents a survey on the relationship between personality dimensions with behavioral biases and availability bias among investment managers in the Tehran Stock Exchange using SPSS software, descriptive and inferential statistics. The necessary data are collected through questionnaire and they are analyzed using some statistical tests. The preliminary results indicate that there is a relationship between personality dimensions and behavioral biases like conservatism bias and availability bias among the investors in the Tehran Stock Exchange.

  3. Introduction to Unconscious Bias

    Science.gov (United States)

    Schmelz, Joan T.

    2010-05-01

    We all have biases, and we are (for the most part) unaware of them. In general, men and women BOTH unconsciously devalue the contributions of women. This can have a detrimental effect on grant proposals, job applications, and performance reviews. Sociology is way ahead of astronomy in these studies. When evaluating identical application packages, male and female University psychology professors preferred 2:1 to hire "Brian” over "Karen” as an assistant professor. When evaluating a more experienced record (at the point of promotion to tenure), reservations were expressed four times more often when the name was female. This unconscious bias has a repeated negative effect on Karen's career. This talk will introduce the concept of unconscious bias and also give recommendations on how to address it using an example for a faculty search committee. The process of eliminating unconscious bias begins with awareness, then moves to policy and practice, and ends with accountability.

  4. U.S. Geological Survey response to flooding in Texas, May–June 2015

    Science.gov (United States)

    East, Jeffery W.

    2016-04-26

    As a Federal science agency within the Department of the Interior, the U.S. Geological Survey (USGS) collects and disseminates streamflow stage and discharge information along with other types of water information as a major part of its Water mission area. Data collected at USGS streamflow-gaging stations (hereinafter referred to as “streamgages”) are used for a variety of purposes including flood warning, engineering design, management of water resources, and scientific research.During flood events, the need for timely, accurate, and complete streamflow data is underscored because these data are relied on by local, State, and Federal emergency management personnel for flood response purposes. For example, the National Weather Service uses the data from USGS streamgages to develop flood forecasts for specific locations on a river. Tasks that the USGS performs in response to floods include monitoring the operation of gages and responding to any interruptions in data collection, calibrating and verifying stage-discharge ratings, and documenting extreme events including peak stage and peak discharge.Frequent, severe storms during May and June 2015 caused widespread flooding in Texas. By various measures, the storms that caused the flooding were extreme and persistent. May 2015 was the wettest month on record for Texas, with a statewide average precipitation of 9.06 inches. In comparison, the long-term statewide average monthly precipitation is 3.37 inches, with the previous record average monthly precipitation reported as 6.66 inches during June 2004. The Office of the Texas State Climatologist compiled monthly precipitation amounts for 19 selected cities throughout Texas and for 1 city in Louisiana; the total monthly precipitation amounts exceeded the monthly normal precipitation for 18 of the 19 selected cities in Texas, with 5 of these cities exceeding their previous record for the month of May.The onset of abundant precipitation in May 2015 resulted in the

  5. Increasingly minimal bias routing

    Energy Technology Data Exchange (ETDEWEB)

    Bataineh, Abdulla; Court, Thomas; Roweth, Duncan

    2017-02-21

    A system and algorithm configured to generate diversity at the traffic source so that packets are uniformly distributed over all of the available paths, but to increase the likelihood of taking a minimal path with each hop the packet takes. This is achieved by configuring routing biases so as to prefer non-minimal paths at the injection point, but increasingly prefer minimal paths as the packet proceeds, referred to herein as Increasing Minimal Bias (IMB).

  6. The effects of sampling bias and model complexity on the predictive performance of MaxEnt species distribution models.

    Science.gov (United States)

    Syfert, Mindy M; Smith, Matthew J; Coomes, David A

    2013-01-01

    Species distribution models (SDMs) trained on presence-only data are frequently used in ecological research and conservation planning. However, users of SDM software are faced with a variety of options, and it is not always obvious how selecting one option over another will affect model performance. Working with MaxEnt software and with tree fern presence data from New Zealand, we assessed whether (a) choosing to correct for geographical sampling bias and (b) using complex environmental response curves have strong effects on goodness of fit. SDMs were trained on tree fern data, obtained from an online biodiversity data portal, with two sources that differed in size and geographical sampling bias: a small, widely-distributed set of herbarium specimens and a large, spatially clustered set of ecological survey records. We attempted to correct for geographical sampling bias by incorporating sampling bias grids in the SDMs, created from all georeferenced vascular plants in the datasets, and explored model complexity issues by fitting a wide variety of environmental response curves (known as "feature types" in MaxEnt). In each case, goodness of fit was assessed by comparing predicted range maps with tree fern presences and absences using an independent national dataset to validate the SDMs. We found that correcting for geographical sampling bias led to major improvements in goodness of fit, but did not entirely resolve the problem: predictions made with clustered ecological data were inferior to those made with the herbarium dataset, even after sampling bias correction. We also found that the choice of feature type had negligible effects on predictive performance, indicating that simple feature types may be sufficient once sampling bias is accounted for. Our study emphasizes the importance of reducing geographical sampling bias, where possible, in datasets used to train SDMs, and the effectiveness and essentialness of sampling bias correction within MaxEnt.

  7. "Suntelligence" Survey

    Science.gov (United States)

    ... to the American Academy of Dermatology's "Suntelligence" sun-smart survey. Please answer the following questions to measure ... be able to view a ranking of major cities suntelligence based on residents' responses to this survey. ...

  8. Medical journal peer review: process and bias.

    Science.gov (United States)

    Manchikanti, Laxmaiah; Kaye, Alan D; Boswell, Mark V; Hirsch, Joshua A

    2015-01-01

    Scientific peer review is pivotal in health care research in that it facilitates the evaluation of findings for competence, significance, and originality by qualified experts. While the origins of peer review can be traced to the societies of the eighteenth century, it became an institutionalized part of the scholarly process in the latter half of the twentieth century. This was a response to the growth of research and greater subject specialization. With the current increase in the number of specialty journals, the peer review process continues to evolve to meet the needs of patients, clinicians, and policy makers. The peer review process itself faces challenges. Unblinded peer review might suffer from positive or negative bias towards certain authors, specialties, and institutions. Peer review can also suffer when editors and/or reviewers might be unable to understand the contents of the submitted manuscript. This can result in an inability to detect major flaws, or revelations of major flaws after acceptance of publication by the editors. Other concerns include potentially long delays in publication and challenges uncovering plagiarism, duplication, corruption and scientific misconduct. Conversely, a multitude of these challenges have led to claims of scientific misconduct and an erosion of faith. These challenges have invited criticism of the peer review process itself. However, despite its imperfections, the peer review process enjoys widespread support in the scientific community. Peer review bias is one of the major focuses of today's scientific assessment of the literature. Various types of peer review bias include content-based bias, confirmation bias, bias due to conservatism, bias against interdisciplinary research, publication bias, and the bias of conflicts of interest. Consequently, peer review would benefit from various changes and improvements with appropriate training of reviewers to provide quality reviews to maintain the quality and integrity of

  9. Biased causal inseparable game

    CERN Document Server

    Bhattacharya, Some Sankar

    2015-01-01

    Here we study the \\emph{causal inseparable} game introduced in [\\href{http://www.nature.com/ncomms/journal/v3/n10/full/ncomms2076.html}{Nat. Commun. {\\bf3}, 1092 (2012)}], but it's biased version. Two separated parties, Alice and Bob, generate biased bits (say input bit) in their respective local laboratories. Bob generates another biased bit (say decision bit) which determines their goal: whether Alice has to guess Bob's bit or vice-verse. Under the assumption that events are ordered with respect to some global causal relation, we show that the success probability of this biased causal game is upper bounded, giving rise to \\emph{biased causal inequality} (BCI). In the \\emph{process matrix} formalism, which is locally in agreement with quantum physics but assume no global causal order, we show that there exist \\emph{inseparable} process matrices that violate the BCI for arbitrary bias in the decision bit. In such scenario we also derive the maximal violation of the BCI under local operations involving tracele...

  10. Area-aggregated assessments of perceived environmental attributes may overcome single-source bias in studies of green environments and health: results from a cross-sectional survey in southern Sweden

    Directory of Open Access Journals (Sweden)

    Wadbro John

    2011-01-01

    Full Text Available Abstract Background Most studies assessing health effects of neighborhood characteristics either use self-reports or objective assessments of the environment, the latter often based on Geographical Information Systems (GIS. While objective measures require detailed landscape data, self-assessments may yield confounded results. In this study we demonstrate how self-assessments of green neighborhood environments aggregated to narrow area units may serve as an appealing compromise between objective measures and individual self-assessments. Methods The study uses cross-sectional data (N = 24,847 from a public health survey conducted in the county of Scania, southern Sweden, in 2008 and validates the Scania Green Score (SGS, a new index comprising five self-reported green neighborhood qualities (Culture, Lush, Serene, Spacious and Wild. The same qualities were also assessed objectively using landscape data and GIS. A multilevel (ecometric model was used to aggregate individual self-reports to assessments of perceived green environmental attributes for areas of 1,000 square meters. We assessed convergent and concurrent validity for self-assessments of the five items separately and for the sum score, individually and area-aggregated. Results Correlations between the index scores based on self-assessments and the corresponding objective assessments were clearly present, indicating convergent validity, but the agreement was low. The correlation was even more evident for the area-aggregated SGS. All three scores (individual SGS, area-aggregated SGS and GIS index score were associated with neighborhood satisfaction, indicating concurrent validity. However, while individual SGS was associated with vitality, this association was not present for aggregated SGS and the GIS-index score, suggesting confounding (single-source bias when individual SGS was used. Conclusions Perceived and objectively assessed qualities of the green neighborhood environment correlate

  11. Effects of incentive size and timing on response rates to a follow-up wave of a longitudinal mailed survey.

    Science.gov (United States)

    Collins, R L; Ellickson, P L; Hays, R D; McCaffrey, D F

    2000-08-01

    Young adults who had previously participated in a longitudinal survey of youth were sent a questionnaire. They were randomly assigned to receive a $20 prepayment, a $20 postpayment, or a $25 postpayment for participation in the latest survey. Those in the large incentive condition were 7 percentage points more likely to return a survey than those in the smaller, postpayment group. Prepayment had a smaller, less reliable effect. Effects of incentive magnitude and timing were consistent at each month of the study period; only better high school grades distinguished early responders from late responders. Nonresponders had characteristics suggestive of low social conformity and were more likely than responders to be African American and male and have low SES. The discussion centers on motivations for participating in research and differences in the incentives likely to promote continued response versus initial study enrollment.

  12. Radiation Response of Forward Biased Float Zone and Magnetic Czochralski Silicon Detectors of Different Geometry for 1-MeV Neutron Equivalent Fluence Monitoring

    CERN Document Server

    Mekki, J; Dusseau, Laurent; Roche, Nicolas Jean-Henri; Saigne, Frederic; Mekki, Julien; Glaser, Maurice

    2010-01-01

    Aiming at evaluating new options for radiation monitoring sensors in LHC/SLHC experiments, the radiation responses of FZ and MCz custom made silicon detectors of different geometry have been studied up to about 4 x 10(14) n(eq)/cm(2). The radiation response of the devices under investigation is discussed in terms of material type, thickness and active area influence.

  13. Reducing hypothetical bias in choice experiments

    DEFF Research Database (Denmark)

    Ladenburg, Jacob; Olsen, Søren Bøye; Nielsen, Rasmus Christian Fejer

    eliminate some of the hypothetical bias. The present paper tests an addition to Cheap Talk, an Opt-Out Reminder. The Opt-Out Reminder is an objective short script presented prior to the choice sets, prompting the respondent to choose the opt-out alternative, if he/she finds the proposed policy generated...... alternatives in a choice set too expensive. The results suggest that adding an Opt-Out Reminder to Cheap Talk can in fact reduce hypothetical bias even further and reduces some of the ineffectiveness of CT in relation to the survey bid range and experienced respondents....

  14. The effect of non-response on estimates of health care utilisation

    DEFF Research Database (Denmark)

    Gundgaard, Jens; Ekholm, Orla; Hansen, Ebba Holme;

    2008-01-01

    living in Funen County. Data were linked with register information on health care utilisation in hospitals and primary care. Health care utilisation was estimated for respondents and non-respondents, and the difference was explained by a decomposition method of bias components. RESULTS: The surveys......-contact, and other reasons were less frequent. Respondents used 3-6% less health care than non-respondents at the aggregate level, but the opposite was true for some specific types of health care. Non-response due to illness was the main contributor to non-response bias. CONCLUSIONS: Different types of non......BACKGROUND: Non-response in health surveys may lead to bias in estimates of health care utilisation. The magnitude, direction and composition of the bias are usually not well known. When data from health surveys are merged with data from registers at the individual level, analyses can reveal non...

  15. Self-reported responsiveness to direct-to-consumer drug advertising and medication use: results of a national survey

    Directory of Open Access Journals (Sweden)

    Somes Grant W

    2011-09-01

    Full Text Available Abstract Background Direct-to-consumer (DTC marketing of pharmaceuticals is controversial, yet effective. Little is known relating patterns of medication use to patient responsiveness to DTC. Methods We conducted a secondary analysis of data collected in national telephone survey on knowledge of and attitudes toward DTC advertisements. The survey of 1081 U.S. adults (response rate = 65% was conducted by the Food and Drug Administration (FDA. Responsiveness to DTC was defined as an affirmative response to the item: "Has an advertisement for a prescription drug ever caused you to ask a doctor about a medical condition or illness of your own that you had not talked to a doctor about before?" Patients reported number of prescription and over-the-counter (OTC medicines taken as well as demographic and personal health information. Results Of 771 respondents who met study criteria, 195 (25% were responsive to DTC. Only 7% respondents taking no prescription were responsive, whereas 45% of respondents taking 5 or more prescription medications were responsive. This trend remained significant (p trend .0009 even when controlling for age, gender, race, educational attainment, income, self-reported health status, and whether respondents "liked" DTC advertising. There was no relationship between the number of OTC medications taken and the propensity to discuss health-related problems in response to DTC advertisements (p = .4. Conclusion There is a strong cross-sectional relationship between the number of prescription, but not OTC, drugs used and responsiveness to DTC advertising. Although this relationship could be explained by physician compliance with patient requests for medications, it is also plausible that DTC advertisements have a particular appeal to patients prone to taking multiple medications. Outpatients motivated to discuss medical conditions based on their exposure to DTC advertising may require a careful medication history to evaluate for

  16. Helminth-excreted/secreted products are recognized by multiple receptors on DCs to block the TLR response and bias Th2 polarization in a cRAF dependent pathway

    Science.gov (United States)

    Terrazas, César A.; Alcántara-Hernández, Marcela; Bonifaz, Laura; Terrazas, Luis I.; Satoskar, Abhay R.

    2013-01-01

    Dendritic cells (DCs) recognize pathogens and initiate the T-cell response. The DC-helminth interaction induces an immature phenotype in DCs; as a result, these DCs display impaired responses to TLR stimulation and prime Th2-type responses. However, the DC receptors and intracellular pathways targeted by helminth molecules and their importance in the initiation of the Th2 response are poorly understood. In this report, we found that products excreted/secreted by Taenia crassiceps (TcES) triggered cRAF phosphorylation through MGL, MR, and TLR2. TcES interfered with the LPS-induced NFκB p65 and p38 MAPK signaling pathways. In addition, TcES-induced cRAF signaling pathway was critical for down-regulation of the TLR-mediated DC maturation and secretion of IL-12 and TNF-α. Finally, we show for the first time that blocking cRAF in DCs abolishes their ability to induce Th2 polarization in vitro after TcES exposure. Our data demonstrate a new mechanism by which helminths target intracellular pathways to block DC maturation and efficiently program Th2 polarization.—Terrazas, C. A., Alcántara-Hernández, M., Bonifaz, L., Terrazas, L. I., Satoskar, A. R. Helminth-excreted/secreted products are recognized by multiple receptors on DCs to block the TLR response and bias Th2 polarization in a cRAF dependent pathway. PMID:23907435

  17. The influence of labels associated with anchor points of Likert-type response scales in survey questionnaires.

    Science.gov (United States)

    Blais, Jean-Guy; Grondin, Julie

    2011-01-01

    Survey questionnaires are among the most used data gathering techniques in the social sciences researchers' toolbox and many factors can influence respondents' answers on items and affect data validity. Among these factors, research has accumulated which demonstrates that verbal and numeric labels associated with item's response categories in such questionnaire may influence substantially the way in which respondents operate their choices within the proposed response format. In line with these findings, the focus of this article is to use Andrich's Rating scale model to illustrate what kind of influence the quantifier adverb "totally," used to label or emphasize extreme categories, could have on respondents' answers.

  18. Climate Change and Infectious Disease Risk in Western Europe: A Survey of Dutch Expert Opinion on Adaptation Responses and Actors.

    Science.gov (United States)

    Akin, Su-Mia; Martens, Pim; Huynen, Maud M T E

    2015-08-18

    There is growing evidence of climate change affecting infectious disease risk in Western Europe. The call for effective adaptation to this challenge becomes increasingly stronger. This paper presents the results of a survey exploring Dutch expert perspectives on adaptation responses to climate change impacts on infectious disease risk in Western Europe. Additionally, the survey explores the expert sample's prioritization of mitigation and adaptation, and expert views on the willingness and capacity of relevant actors to respond to climate change. An integrated view on the causation of infectious disease risk is employed, including multiple (climatic and non-climatic) factors. The results show that the experts consider some adaptation responses as relatively more cost-effective, like fostering interagency and community partnerships, or beneficial to health, such as outbreak investigation and response. Expert opinions converge and diverge for different adaptation responses. Regarding the prioritization of mitigation and adaptation responses expert perspectives converge towards a 50/50 budgetary allocation. The experts consider the national government/health authority as the most capable actor to respond to climate change-induced infectious disease risk. Divergence and consensus among expert opinions can influence adaptation policy processes. Further research is necessary to uncover prevailing expert perspectives and their roots, and compare these.

  19. Climate Change and Infectious Disease Risk in Western Europe: A Survey of Dutch Expert Opinion on Adaptation Responses and Actors

    Science.gov (United States)

    Akin, Su-Mia; Martens, Pim; Huynen, Maud M.T.E.

    2015-01-01

    There is growing evidence of climate change affecting infectious disease risk in Western Europe. The call for effective adaptation to this challenge becomes increasingly stronger. This paper presents the results of a survey exploring Dutch expert perspectives on adaptation responses to climate change impacts on infectious disease risk in Western Europe. Additionally, the survey explores the expert sample’s prioritization of mitigation and adaptation, and expert views on the willingness and capacity of relevant actors to respond to climate change. An integrated view on the causation of infectious disease risk is employed, including multiple (climatic and non-climatic) factors. The results show that the experts consider some adaptation responses as relatively more cost-effective, like fostering interagency and community partnerships, or beneficial to health, such as outbreak investigation and response. Expert opinions converge and diverge for different adaptation responses. Regarding the prioritization of mitigation and adaptation responses expert perspectives converge towards a 50/50 budgetary allocation. The experts consider the national government/health authority as the most capable actor to respond to climate change-induced infectious disease risk. Divergence and consensus among expert opinions can influence adaptation policy processes. Further research is necessary to uncover prevailing expert perspectives and their roots, and compare these. PMID:26295247

  20. Climate Change and Infectious Disease Risk in Western Europe: A Survey of Dutch Expert Opinion on Adaptation Responses and Actors

    Directory of Open Access Journals (Sweden)

    Su-Mia Akin

    2015-08-01

    Full Text Available There is growing evidence of climate change affecting infectious disease risk in Western Europe. The call for effective adaptation to this challenge becomes increasingly stronger. This paper presents the results of a survey exploring Dutch expert perspectives on adaptation responses to climate change impacts on infectious disease risk in Western Europe. Additionally, the survey explores the expert sample’s prioritization of mitigation and adaptation, and expert views on the willingness and capacity of relevant actors to respond to climate change. An integrated view on the causation of infectious disease risk is employed, including multiple (climatic and non-climatic factors. The results show that the experts consider some adaptation responses as relatively more cost-effective, like fostering interagency and community partnerships, or beneficial to health, such as outbreak investigation and response. Expert opinions converge and diverge for different adaptation responses. Regarding the prioritization of mitigation and adaptation responses expert perspectives converge towards a 50/50 budgetary allocation. The experts consider the national government/health authority as the most capable actor to respond to climate change-induced infectious disease risk. Divergence and consensus among expert opinions can influence adaptation policy processes. Further research is necessary to uncover prevailing expert perspectives and their roots, and compare these.

  1. Nonresponse bias in randomized controlled experiments in criminology: Putting the Queensland Community Engagement Trial (QCET) under a microscope.

    Science.gov (United States)

    Antrobus, Emma; Elffers, Henk; White, Gentry; Mazerolle, Lorraine

    2013-01-01

    The goal of this article is to examine whether or not the results of the Queensland Community Engagement Trial (QCET)-a randomized controlled trial that tested the impact of procedural justice policing on citizen attitudes toward police-were affected by different types of nonresponse bias. We use two methods (Cochrane and Elffers methods) to explore nonresponse bias: First, we assess the impact of the low response rate by examining the effects of nonresponse group differences between the experimental and control conditions and pooled variance under different scenarios. Second, we assess the degree to which item response rates are influenced by the control and experimental conditions. Our analysis of the QCET data suggests that our substantive findings are not influenced by the low response rate in the trial. The results are robust even under extreme conditions, and statistical significance of the results would only be compromised in cases where the pooled variance was much larger for the nonresponse group and the difference between experimental and control conditions was greatly diminished. We also find that there were no biases in the item response rates across the experimental and control conditions. RCTs that involve field survey responses-like QCET-are potentially compromised by low response rates and how item response rates might be influenced by the control or experimental conditions. Our results show that the QCET results were not sensitive to the overall low response rate across the experimental and control conditions and the item response rates were not significantly different across the experimental and control groups. Overall, our analysis suggests that the results of QCET are robust and any biases in the survey responses do not significantly influence the main experimental findings.

  2. Attention Orienting in Response to Non-conscious Hierarchical Arrows: Individuals with Higher Autistic Traits Differ in Their Global/Local Bias

    Science.gov (United States)

    Laycock, Robin; Chan, Daniel; Crewther, Sheila G.

    2017-01-01

    One aspect of the social communication impairments that characterize autism spectrum disorder (ASD) include reduced use of often subtle non-verbal social cues. People with ASD, and those with self-reported sub-threshold autistic traits, also show impairments in rapid visual processing of stimuli unrelated to social or emotional properties. Hence, this study sought to investigate whether perceptually non-conscious visual processing is related to autistic traits. A neurotypical sample of thirty young adults completed the Subthreshold Autism Trait Questionnaire and a Posner-like attention cueing task. Continuous Flash Suppression (CFS) was employed to render incongruous hierarchical arrow cues perceptually invisible prior to consciously presented targets. This was achieved via a 10 Hz masking stimulus presented to the dominant eye that suppressed information presented to the non-dominant eye. Non-conscious arrows consisted of local arrow elements pointing in one direction, and forming a global arrow shape pointing in the opposite direction. On each trial, the cue provided either a valid or invalid cue for the spatial location of the subsequent target, depending on which level (global or local) received privileged attention. A significant autism-trait group by global cue validity interaction indicated a difference in the extent of non-conscious local/global cueing between groups. Simple effect analyses revealed that whilst participants with lower autistic traits showed a global arrow cueing effect, those with higher autistic traits demonstrated a small local arrow cueing effect. These results suggest that non-conscious processing biases in local/global attention may be related to individual differences in autistic traits. PMID:28149288

  3. Is There Bias against Simulation in Microsurgery Training?

    Science.gov (United States)

    Theman, Todd A; Labow, Brian I

    2016-09-01

    Background While other surgical specialties have embraced virtual reality simulation for training and recertification, microsurgery has lagged. This study aims to assess the opinions of microsurgeons on the role of simulation in microsurgery assessment and training. Methods We surveyed faculty members of the American Society of Reconstructive Microsurgery to ascertain opinions on their use of simulation in training and opinions about the utility of simulation for skills acquisition, teaching, and skills assessment. The 21-question survey was disseminated online to 675 members. Results Eighty-nine members completed the survey for a 13.2% response rate. Few microsurgeons have experience with high-fidelity simulation, and opinions on its utility are internally inconsistent. Although 84% of respondents could not identify a reason why simulation would not be useful, only 24% believed simulation is a useful measure of clinical performance. Nearly three-fourths of respondents were skeptical that simulation would improve their skills. Ninety-four percent had no experience with simulator-based assessment. Conclusion Simulation has been shown to improve skills acquisition in microsurgery, but our survey suggests that unfamiliarity may foster bias against the technology. Failure to incorporate simulation may adversely affect training and may put surgeons at a disadvantage should these technologies be adopted for recertification by regulatory agencies.

  4. Mycobacterium tuberculosis PE25/PPE41 protein complex induces activation and maturation of dendritic cells and drives Th2-biased immune responses.

    Science.gov (United States)

    Chen, Wei; Bao, Yige; Chen, Xuerong; Burton, Jeremy; Gong, Xueli; Gu, Dongqing; Mi, Youjun; Bao, Lang

    2016-04-01

    Mycobacterium tuberculosis evades innate host immune responses by parasitizing macrophages and causes significant morbidity and mortality around the world. A mycobacterial antigen that can activate dendritic cells (DCs) and elicit effective host innate immune responses will be vital to the development of an effective TB vaccine. The M. tuberculosis genes PE25/PPE41 encode proteins which have been associated with evasion of the host immune response. We constructed a PE25/PPE41 complex gene via splicing by overlapping extension and expressed it successfully in E. coli. We investigated whether this protein complex could interact with DCs to induce effective host immune responses. The PE25/PPE41 protein complex induced maturation of isolated mouse DCs in vitro, increasing expression of cell surface markers (CD80, CD86 and MHC-II), thereby promoting Th2 polarization via secretion of pro-inflammatory cytokines IL-4 and IL-10. In addition, PE25/PPE41 protein complex-activated DCs induced proliferation of mouse CD4(+) and CD8(+) T cells, and a strong humoral response in immunized mice. The sera of five TB patients were also highly reactive to this antigen. These findings suggest that interaction of the PE25/PPE41 protein complex with DCs may be of great immunological significance.

  5. Systematic tests for position-dependent additive shear bias

    CERN Document Server

    van Uitert, Edo

    2016-01-01

    We present new tests to identify stationary position-dependent additive shear biases in weak gravitational lensing data sets. These tests are important diagnostics for currently ongoing and planned cosmic shear surveys, as such biases induce coherent shear patterns that can mimic and potentially bias the cosmic shear signal. The central idea of these tests is to determine the average ellipticity of all galaxies with shape measurements in a grid in the pixel plane. The distribution of the absolute values of these averaged ellipticities can be compared to randomized catalogues; a difference points to systematics in the data. In addition, we introduce a method to quantify the spatial correlation of the additive bias, which suppresses the contribution from cosmic shear and therefore eases the identification of a position-dependent additive shear bias in the data. We apply these tests to the publicly available shear catalogues from the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS) and the Kilo Degree Su...

  6. Individual and culture-level components of survey response styles: A multi-level analysis using cultural models of selfhood.

    Science.gov (United States)

    Smith, Peter B; Vignoles, Vivian L; Becker, Maja; Owe, Ellinor; Easterbrook, Matthew J; Brown, Rupert; Bourguignon, David; Garðarsdóttir, Ragna B; Kreuzbauer, Robert; Cendales Ayala, Boris; Yuki, Masaki; Zhang, Jianxin; Lv, Shaobo; Chobthamkit, Phatthanakit; Jaafar, Jas Laile; Fischer, Ronald; Milfont, Taciano L; Gavreliuc, Alin; Baguma, Peter; Bond, Michael Harris; Martin, Mariana; Gausel, Nicolay; Schwartz, Seth J; Des Rosiers, Sabrina E; Tatarko, Alexander; González, Roberto; Didier, Nicolas; Carrasco, Diego; Lay, Siugmin; Nizharadze, George; Torres, Ana; Camino, Leoncio; Abuhamdeh, Sami; Macapagal, Ma Elizabeth J; Koller, Silvia H; Herman, Ginette; Courtois, Marie; Fritsche, Immo; Espinosa, Agustín; Villamar, Juan A; Regalia, Camillo; Manzi, Claudia; Brambilla, Maria; Zinkeng, Martina; Jalal, Baland; Kusdil, Ersin; Amponsah, Benjamin; Çağlar, Selinay; Mekonnen, Kassahun Habtamu; Möller, Bettina; Zhang, Xiao; Schweiger Gallo, Inge; Prieto Gil, Paula; Lorente Clemares, Raquel; Campara, Gabriella; Aldhafri, Said; Fülöp, Márta; Pyszczynski, Tom; Kesebir, Pelin; Harb, Charles

    2016-12-01

    Variations in acquiescence and extremity pose substantial threats to the validity of cross-cultural research that relies on survey methods. Individual and cultural correlates of response styles when using 2 contrasting types of response mode were investigated, drawing on data from 55 cultural groups across 33 nations. Using 7 dimensions of self-other relatedness that have often been confounded within the broader distinction between independence and interdependence, our analysis yields more specific understandings of both individual- and culture-level variations in response style. When using a Likert-scale response format, acquiescence is strongest among individuals seeing themselves as similar to others, and where cultural models of selfhood favour harmony, similarity with others and receptiveness to influence. However, when using Schwartz's (2007) portrait-comparison response procedure, acquiescence is strongest among individuals seeing themselves as self-reliant but also connected to others, and where cultural models of selfhood favour self-reliance and self-consistency. Extreme responding varies less between the two types of response modes, and is most prevalent among individuals seeing themselves as self-reliant, and in cultures favouring self-reliance. As both types of response mode elicit distinctive styles of response, it remains important to estimate and control for style effects to ensure valid comparisons. © 2016 International Union of Psychological Science.

  7. Distinguishing Selection Bias and Confounding Bias in Comparative Effectiveness Research.

    Science.gov (United States)

    Haneuse, Sebastien

    2016-04-01

    Comparative effectiveness research (CER) aims to provide patients and physicians with evidence-based guidance on treatment decisions. As researchers conduct CER they face myriad challenges. Although inadequate control of confounding is the most-often cited source of potential bias, selection bias that arises when patients are differentially excluded from analyses is a distinct phenomenon with distinct consequences: confounding bias compromises internal validity, whereas selection bias compromises external validity. Despite this distinction, however, the label "treatment-selection bias" is being used in the CER literature to denote the phenomenon of confounding bias. Motivated by an ongoing study of treatment choice for depression on weight change over time, this paper formally distinguishes selection and confounding bias in CER. By formally distinguishing selection and confounding bias, this paper clarifies important scientific, design, and analysis issues relevant to ensuring validity. First is that the 2 types of biases may arise simultaneously in any given study; even if confounding bias is completely controlled, a study may nevertheless suffer from selection bias so that the results are not generalizable to the patient population of interest. Second is that the statistical methods used to mitigate the 2 biases are themselves distinct; methods developed to control one type of bias should not be expected to address the other. Finally, the control of selection and confounding bias will often require distinct covariate information. Consequently, as researchers plan future studies of comparative effectiveness, care must be taken to ensure that all data elements relevant to both confounding and selection bias are collected.

  8. A Prescription for Galaxy Biasing Evolution as a Nuisance Parameter

    CERN Document Server

    Clerkin, L; Lahav, O; Abdalla, F B; Gaztanaga, E

    2014-01-01

    There is currently no consistent approach to modelling galaxy bias evolution in cosmological inference. This lack of a common standard makes the rigorous comparison or combination of probes difficult. We show that the choice of biasing model has a significant impact on cosmological parameter constraints for a survey such as the Dark Energy Survey (DES), considering the 2-point correlations of galaxies in five tomographic redshift bins. We find that modelling galaxy bias with a free biasing parameter per redshift bin gives a Figure of Merit (FoM) for Dark Energy equation of state parameters $w_0, w_a$ smaller by a factor of 10 than if a constant bias is assumed. An incorrect bias model will also cause a shift in measured values of cosmological parameters. Motivated by these points and focusing on the redshift evolution of linear bias, we propose the use of a generalised galaxy bias which encompasses a range of bias models from theory, observations and simulations, $b(z) = c + (b_0 - c)/D(z)^\\alpha$, where $c, ...

  9. Measuring Agricultural Bias

    DEFF Research Database (Denmark)

    Jensen, Henning Tarp; Robinson, Sherman; Tarp, Finn

    . For the 15 sample countries, the results indicate that the agricultural price incentive bias, which was generally perceived to exist during the 1980s, was largely eliminated during the 1990s. The results also demonstrate that general equilibrium effects and country-specific characteristics - including trade...... shares and intersectoral linkages - are crucial for determining the sign and magnitude of trade policy bias. The GE-ERP measure is therefore uniquely suited to capture the full impact of trade policies on agricultural price incentives. A Monte Carlo procedure confirms that the results are robust...

  10. Measuring agricultural policy bias

    DEFF Research Database (Denmark)

    Jensen, Henning Tarp; Robinson, Sherman; Tarp, Finn

    2010-01-01

    Measurement is a key issue in the literature on price incentive bias induced by trade policy. We introduce a general equilibrium measure of the relative effective rate of protection, which generalizes earlier protection measures. For our fifteen sample countries, results indicate that the agricul......Measurement is a key issue in the literature on price incentive bias induced by trade policy. We introduce a general equilibrium measure of the relative effective rate of protection, which generalizes earlier protection measures. For our fifteen sample countries, results indicate...... protection measure is therefore uniquely suited to capture the full impact of trade policies on relative agricultural price incentives....

  11. Balancing the dual responsibilities of business unit controllers: field and survey evidence

    NARCIS (Netherlands)

    Maas, V.S.; Matejka, M.

    2009-01-01

    We examine how business unit (BU) controllers balance their dual roles of providing information for both local decision-making (local responsibility) and corporate control (functional responsibility). The existing literature suggests that organizations can improve the quality of financial reporting

  12. A prescription for galaxy biasing evolution as a nuisance parameter

    Science.gov (United States)

    Clerkin, L.; Kirk, D.; Lahav, O.; Abdalla, F. B.; Gaztañaga, E.

    2015-04-01

    There is currently no consistent approach to modelling galaxy bias evolution in cosmological inference. This lack of a common standard makes the rigorous comparison or combination of probes difficult. We show that the choice of biasing model has a significant impact on cosmological parameter constraints for a survey such as the Dark Energy Survey (DES), considering the two-point correlations of galaxies in five tomographic redshift bins. We find that modelling galaxy bias with a free biasing parameter per redshift bin gives a Figure of Merit (FoM) for dark energy equation of state parameters w0, wa smaller by a factor of 10 than if a constant bias is assumed. An incorrect bias model will also cause a shift in measured values of cosmological parameters. Motivated by these points and focusing on the redshift evolution of linear bias, we propose the use of a generalized galaxy bias which encompasses a range of bias models from theory, observations and simulations, b(z) = c + (b0 - c)/D(z)α, where parameters c, b0 and α depend on galaxy properties such as halo mass. For a DES-like galaxy survey, we find that this model gives an unbiased estimate of w0, wa with the same number or fewer nuisance parameters and a higher FoM than a simple b(z) model allowed to vary in z-bins. We show how the parameters of this model are correlated with cosmological parameters. We fit a range of bias models to two recent data sets, and conclude that this generalized parametrization is a sensible benchmark expression of galaxy bias on large scales.

  13. European survey on laboratory preparedness, response and diagnostic capacity for crimean-congo haemorrhagic fever, 2012

    NARCIS (Netherlands)

    M.D. Fernandez-Garcia (Maria Dolores); A. Negredo; A. Papa (Anna); O. Donoso-Mantke; M. Niedrig; H. Zeller; A. Tenorio; L. Franco (Leticia); S.W. Aberle (Stephan W.); M. van Esbroeck (M.); I. Christova; A. Markotic (Alemka); I.-C. Kurolt (Ivan-Christian); H. Zelena (Hana); I. Golovljova; D. Pannetier (Delphine); R. Charrel (Remi); J. Schmidt-Chanasit (Jonas); R. Wölfel (Roman); A. Papa (Anna); M.R. Capobianchi (Maria Rosaria); X. Jakupi (Xhevat); J. Storozenko (Jelena); A. Griskevicius (Algis); G. Bosevska (Golubinka); C. Muscat (Clive); M. Schutten (Martin); S.G. Dudman (Susanne Gjeruldsen); M.J. Alves (M. João); C.S. Ceianu; A. Platonov (Alexander); B. Bozovic (Bojana); B. Klempa; T. Avsic (Tatjana); A. Tenorio; Å. Lundkvist (Åke); P. Cherpillod (Pascal); G. Korukluoglu; D.W.G. Brown (D. W G); T. Brooks (Tim)

    2014-01-01

    textabstractCrimean-Congo haemorrhagic fever (CCHF) is an infectious viral disease that has (re-)emerged in the last decade in south-eastern Europe, and there is a risk for further geographical expansion to western Europe. Here we report the results of a survey covering 28 countries, conducted in 20

  14. Testing the Canon: Student Responses to Texts by Medieval Women in English Literature Surveys.

    Science.gov (United States)

    Hawkins, Ann R.

    While there has been a great deal of debate about enlarging the canon, less attention has been paid to how students respond to "new" literary figures such as Margery Kempe and Julian of Norwich, or to how instructors should incorporate them into an already cramped literature survey course. Instructors must consider some questions that…

  15. The Development of an Emotional Response to Writing Measure: The Affective Cognition Writing Survey

    Science.gov (United States)

    Fischer, Ronald G.; Fischer, Jerome M.; Jain, Sachin

    2010-01-01

    This study was designed to develop and initiate the validation of the Affective Cognition Writing Survey (ACWS), a psychological instrument used to measure emotional expression through writing. Procedures for development and validation of the instrument are reported. Subsequently, factor analysis extracted six factors: Positive Processing,…

  16. Framing Higher Education: Questions and Responses in the British Social Attitudes Survey, 1983-2010

    Science.gov (United States)

    Mountford-Zimdars, Anna; Jones, Steven; Sullivan, Alice; Heath, Anthony

    2013-01-01

    This article focuses on questions and attitudes towards higher education in the British Social Attitudes (BSA) survey series. First, we analyse the changing BSA questions (1983-2010) in the context of key policy reports. Our results show that changes in the framing of higher education questions correspond with changes in the macro-discourse of…

  17. 2011 Workplace and Equal Opportunity Survey of Reserve Component Members: Tabulations of Responses

    Science.gov (United States)

    2014-03-01

    230  2011 Workplace and Equal Opportunity Survey of Reserve Component Members DMDC ix b.  Feeling down, depressed , or hopeless... Depression scale: Constructed from Q59. Depression is a common mental disorder characterized by depressed mood, loss of interest or pleasure...graffiti, music , stories) which were racist or showed your race/ethnicity negatively

  18. Crisis Response in the Public Schools: A Survey of School Psychologists' Experiences and Perceptions

    Science.gov (United States)

    Adamson, Austin D.; Peacock, Gretchen Gimpel

    2007-01-01

    In this study, 228 school psychologists completed a survey regarding crisis intervention teams and plans. The majority of respondents indicated their schools had crisis plans (95.1%) and teams (83.6%). The most common team activities endorsed by participants involved providing direct assistance and services to students, staff, and the media. The…

  19. Austin Community College Management Response to Employee Satisfaction Survey, Spring 2000.

    Science.gov (United States)

    Austin Community Coll., TX.

    Findings from an Employee Satisfaction Survey conducted in spring 2000 at Austin Community College (ACC) (Texas) indicate that: (1) staff in many areas need customer service training; (2) telephones are not used effectively by many offices; (3) many areas are not able to respond quickly to the needs of college staff; and (4) 18 highly used areas…

  20. Measuring subjective response to aircraft noise: The effects of survey context

    NARCIS (Netherlands)

    Kroesen, M.; Molin, E.J.E.; Van Wee, G.P.

    2013-01-01

    In applied research, noise annoyance is often used as indicator of subjective reaction to aircraft noise in residential areas. The present study aims to show that the meaning which respondents attach to the concept of aircraft noise annoyance is partly a function of survey context. To this purpose a

  1. Are Divorce Studies Trustworthy? The Effects of Survey Nonresponse and Response Errors

    Science.gov (United States)

    Mitchell, Colter

    2010-01-01

    Researchers rely on relationship data to measure the multifaceted nature of families. This article speaks to relationship data quality by examining the ramifications of different types of error on divorce estimates, models predicting divorce behavior, and models employing divorce as a predictor. Comparing matched survey and divorce certificate…

  2. Rates, Delays, and Completeness of General Practitioners’ Responses to a Postal Versus Web-Based Survey: A Randomized Trial

    Science.gov (United States)

    Maisonneuve, Hubert; Cerutti, Bernard; Fournier, Jean Pascal; Senn, Nicolas; Haller, Dagmar M

    2017-01-01

    Background Web-based surveys have become a new and popular method for collecting data, but only a few studies have directly compared postal and Web-based surveys among physicians, and none to our knowledge among general practitioners (GPs). Objective Our aim is to compare two modes of survey delivery (postal and Web-based) in terms of participation rates, response times, and completeness of questionnaires in a study assessing GPs’ preventive practices. Methods This randomized study was conducted in Western Switzerland (Geneva and Vaud) and in France (Alsace and Pays de la Loire) in 2015. A random selection of community-based GPs (1000 GPs in Switzerland and 2400 GPs in France) were randomly allocated to receive a questionnaire about preventive care activities either by post (n=700 in Switzerland, n=400 in France) or by email (n=300 in Switzerland, n=2000 in France). Reminder messages were sent once in the postal group and twice in the Web-based group. Any GPs practicing only complementary and alternative medicine were excluded from the study. Results Among the 3400 contacted GPs, 764 (22.47%, 95% CI 21.07%-23.87%) returned the questionnaire. Compared to the postal group, the participation rate in the Web-based group was more than four times lower (246/2300, 10.70% vs 518/1100, 47.09%, Pparticipation in surveys while reducing costs. PMID:28330830

  3. Simulating currency substitution bias

    NARCIS (Netherlands)

    M. Boon (Martin); C.J.M. Kool (Clemens); C.G. de Vries (Casper)

    1989-01-01

    textabstractThe sign and size of estimates of the elasticity of currency substitution critically depend on the definition of the oppurtunity costs of holding money. We investigate possible biases by means of Monte Carlo experiments, as sufficient real data are not available.

  4. Sex Bias in Children.

    Science.gov (United States)

    Zalk, Sue Rosenberg; And Others

    This study investigated children's sex biased attitudes as a function of the sex, age, and race of the child as well as a geographical-SES factor. Two attitudes were measured on a 55-item questionnaire: Sex Pride (attributing positive characteristics to a child of the same sex) and Sex Prejudice (attributing negative characteristics to a child of…

  5. Differences in the effects of turns and constrictions on the resistive response in current-biased superconducting wire after single photon absorption

    OpenAIRE

    Zotova, A. N.; Vodolazov, D. Y.

    2013-01-01

    We study how turns and constrictions affect the resistive response of the superconducting wire after instant in time and local in space heating, which models the absorption of the single photon by the wire. We find that the presence of constriction favors detection of photons of various energies but the presence of turn increases only ability to detect relatively "low" energy photons. The main reason is that in case of constriction the current density is increased over whole length and width ...

  6. Medical School Factors Associated with Changes in Implicit and Explicit Bias Against Gay and Lesbian People among 3492 Graduating Medical Students.

    Science.gov (United States)

    Phelan, Sean M; Burke, Sara E; Hardeman, Rachel R; White, Richard O; Przedworski, Julia; Dovidio, John F; Perry, Sylvia P; Plankey, Michael; A Cunningham, Brooke; Finstad, Deborah; W Yeazel, Mark; van Ryn, Michelle

    2017-08-01

    Implicit and explicit bias among providers can influence the quality of healthcare. Efforts to address sexual orientation bias in new physicians are hampered by a lack of knowledge of school factors that influence bias among students. To determine whether medical school curriculum, role modeling, diversity climate, and contact with sexual minorities predict bias among graduating students against gay and lesbian people. Prospective cohort study. A sample of 4732 first-year medical students was recruited from a stratified random sample of 49 US medical schools in the fall of 2010 (81% response; 55% of eligible), of which 94.5% (4473) identified as heterosexual. Seventy-eight percent of baseline respondents (3492) completed a follow-up survey in their final semester (spring 2014). Medical school predictors included formal curriculum, role modeling, diversity climate, and contact with sexual minorities. Outcomes were year 4 implicit and explicit bias against gay men and lesbian women, adjusted for bias at year 1. In multivariate models, lower explicit bias against gay men and lesbian women was associated with more favorable contact with LGBT faculty, residents, students, and patients, and perceived skill and preparedness for providing care to LGBT patients. Greater explicit bias against lesbian women was associated with discrimination reported by sexual minority students (b = 1.43 [0.16, 2.71]; p = 0.03). Lower implicit sexual orientation bias was associated with more frequent contact with LGBT faculty, residents, students, and patients (b = -0.04 [-0.07, -0.01); p = 0.008). Greater implicit bias was associated with more faculty role modeling of discriminatory behavior (b = 0.34 [0.11, 0.57); p = 0.004). Medical schools may reduce bias against sexual minority patients by reducing negative role modeling, improving the diversity climate, and improving student preparedness to care for this population.

  7. Monitoring physiology trainee needs to focus professional society responses: the APS Trainee Needs Surveys.

    Science.gov (United States)

    Matyas, Marsha L; Lowy, Melinda E; Sweazea, Karen L; Alvarez, Diego F

    2011-06-01

    In 2004 and 2007, the American Physiological Society (APS) Trainee Advisory Committee (TAC) conducted surveys of graduate students, postdoctoral fellows, and new investigators in physiology to identify topics and issues important to those trainees. Two major trends emerged from the data. First, trainees in 2007 expressed somewhat greater interest in professional development information than did those in 2004. Second, needs expressed by trainees in both years were closely related to their specific career development stage. Survey findings guided the TAC and other APS committees and groups to focus their efforts toward the issues that were of the greatest interest to trainees. It also led to improved communication with trainees and increased involvement of trainees in APS governance.

  8. A survey of some ovarian abnormalities responsible for sterility in Damascus goats

    Directory of Open Access Journals (Sweden)

    A survey of some ovarian abnormalities responsible for sterility in Damascus goats M. Roukbi

    2013-12-01

    Full Text Available A survey of some ovarian abnormalities in 13 Damascus goats with normal to masculinized genitalia, aged 1.5 to 6 years was conducted to determine some types of disorders affecting the ovaries in light of their morphological findings with reference to obstetrics and gynecology literature. The results showed persistent follicles and cystic ovarian disease in phenotypically females, epidermal neoplasms, gonads dysgenesis and dysgenesic gonad tumors in goats with intersex appearance, similar to ovarian tumors in women

  9. 2015 Workplace and Gender Relations Survey of Reserve Component Members: Tabulations of Responses

    Science.gov (United States)

    2016-03-17

    3 gender , relationship status, and race/ethnicity. 2. Time Reference— Important key events to provide frame of reference for respondents on the time...enforcing sexual harassment or Equal Opportunity regulations (Q63c/Q63d). NR: Not reportable NA: Not applicable 2015 Workplace and Gender Relations... Equal Opportunity regulations (Q63c/Q63d). NR: Not reportable NA: Not applicable 2015 Workplace and Gender Relations Survey of Reserve Component

  10. 2012 Workplace and Gender Relations Survey of Active Duty Members. Tabulations of Responses

    Science.gov (United States)

    2013-04-01

    enjoyment , and the opportunity to acquire valuable skills .................................................. 96 15. Overall, how well prepared...538 87. Suppose you see a Service member, who you do not know very well, getting drunk at a party. Someone tells you that one of...The composite measure includes survey items on sense of pride, use of skills, work enjoyment , and the opportunity to acquire valuable skills (Q14a-d

  11. Unconscious race and social class bias among acute care surgical clinicians and clinical treatment decisions.

    Science.gov (United States)

    Haider, Adil H; Schneider, Eric B; Sriram, N; Dossick, Deborah S; Scott, Valerie K; Swoboda, Sandra M; Losonczy, Lia; Haut, Elliott R; Efron, David T; Pronovost, Peter J; Lipsett, Pamela A; Cornwell, Edward E; MacKenzie, Ellen J; Cooper, Lisa A; Freischlag, Julie A

    2015-05-01

    Significant health inequities persist among minority and socially disadvantaged patients. Better understanding of how unconscious biases affect clinical decision making may help to illuminate clinicians' roles in propagating disparities. To determine whether clinicians' unconscious race and/or social class biases correlate with patient management decisions. We conducted a web-based survey among 230 physicians from surgery and related specialties at an academic, level I trauma center from December 1, 2011, through January 31, 2012. We administered clinical vignettes, each with 3 management questions. Eight vignettes assessed the relationship between unconscious bias and clinical decision making. We performed ordered logistic regression analysis on the Implicit Association Test (IAT) scores and used multivariable analysis to determine whether implicit bias was associated with the vignette responses. Differential response times (D scores) on the IAT as a surrogate for unconscious bias. Patient management vignettes varied by patient race or social class. Resulting D scores were calculated for each management decision. In total, 215 clinicians were included and consisted of 74 attending surgeons, 32 fellows, 86 residents, 19 interns, and 4 physicians with an undetermined level of education. Specialties included surgery (32.1%), anesthesia (18.1%), emergency medicine (18.1%), orthopedics (7.9%), otolaryngology (7.0%), neurosurgery (7.0%), critical care (6.0%), and urology (2.8%); 1.9% did not report a departmental affiliation. Implicit race and social class biases were present in most respondents. Among all clinicians, mean IAT D scores for race and social class were 0.42 (95% CI, 0.37-0.48) and 0.71 (95% CI, 0.65-0.78), respectively. Race and class scores were similar across departments (general surgery, orthopedics, urology, etc), race, or age. Women demonstrated less bias concerning race (mean IAT D score, 0.39 [95% CI, 0.29-0.49]) and social class (mean IAT D score

  12. Pitfalls of Quantitative Surveys Online

    Directory of Open Access Journals (Sweden)

    Iva Pecáková

    2016-12-01

    Full Text Available With the development of the Internet in the last two decades, its use in all phases of field survey is growing very quickly. Indeed, it reduces costs while allowing exploration of relatively large files and enables effective use of a variety of research tools. The academic research is more reserved towards developing online surveys. Demands on the quality of data are the main cause; Internet surveys do not meet them and thus do not allow drawing objective conclusion about the populations surveyed. Unqualified use of the Internet may significantly influence data and information obtained from their analysis. The problematic definition of the population that is under investigation may result in a fault of its coverage. Its existence can be shown, for example, on a confrontation of the total and Internet population of the Czech Republic, the total and Internet population of the Czech households, etc. Representation of the population through an online panel may cause bias, depending on how the panel is created. A relatively new source of error in an online survey is the existence of “professional” respondents. The sampling method from a population or an online panel can lead to the emergence of such a sample that is not representative and does not allow inference to the population at all, or only in a very limited way. Even probability sampling, however, can be problematic if it is affected by a higher rate of non-responses. The aim of this paper is to summarise the possible sources of bias associated with any sample survey, but also to draw attention to those that are relatively new and are associated with the implementation of just quantitative surveys online.

  13. Survey and online discussion groups to develop a patient-rated outcome measure on acceptability of treatment response in vitiligo.

    Science.gov (United States)

    Tour, Selina K; Thomas, Kim S; Walker, Dawn-Marie; Leighton, Paul; Yong, Adrian Sw; Batchelor, Jonathan M

    2014-06-14

    Vitiligo is a chronic depigmenting skin disorder which affects around 0.5-1% of the world's population. The outcome measures used most commonly in trials to judge treatment success focus on repigmentation. Patient-reported outcome measures of treatment success are rarely used, although recommendations have been made for their inclusion in vitiligo trials. This study aimed to evaluate the face validity of a new patient-reported outcome measure of treatment response, for use in future trials and clinical practice. An online survey to gather initial views on what constitutes treatment success for people with vitiligo or their parents/carers, followed by online discussion groups with patients to reach consensus on what constitutes treatment success for individuals with vitiligo, and how this can be assessed in the context of trials. Participants were recruited from an existing database of vitiligo patients and through posts on the social network sites Facebook and Twitter. A total of 202 survey responses were received, of which 37 were excluded and 165 analysed. Three main themes emerged as important in assessing treatment response: a) the match between vitiligo and normal skin (how well it blends in); b) how noticeable the vitiligo is and c) a reduction in the size of the white patches. The majority of respondents said they would consider 80% or more repigmentation to be a worthwhile treatment response after 9 months of treatment. Three online discussion groups involving 12 participants led to consensus that treatment success is best measured by asking patients how noticeable their vitiligo is after treatment. This was judged to be best answered using a 5-point Likert scale, on which a score of 4 or 5 represents treatment success. This study represents the first step in developing a patient reported measure of treatment success in vitiligo trials. Further work is now needed to assess its construct validity and responsiveness to change.

  14. Responses to language barriers in consultations with refugees and asylum seekers: a telephone survey of Irish general practitioners.

    LENUS (Irish Health Repository)

    MacFarlane, Anne

    2008-01-01

    BACKGROUND: Refugees and asylum seekers experience language barriers in general practice. Qualitative studies have found that responses to language barriers in general practice are ad hoc with use of both professional interpreters and informal interpreters (patients\\' relatives or friends). However, the scale of the issues involved is unknown. This study quantifies the need for language assistance in general practice consultations and examines the experience of, and satisfaction with, methods of language assistance utilized. METHODS: Data were collected by telephone survey with general practitioners in a regional health authority in Ireland between July-August 2004. Each respondent was asked a series of questions about consulting with refugees and asylum seekers, the need for language assistance and the kind of language assistance used. RESULTS: There was a 70% (n = 56\\/80) response rate to the telephone survey. The majority of respondents (77%) said that they had experienced consultations with refugees and asylum seekers in which language assistance was required. Despite this, general practitioners in the majority of cases managed without an interpreter or used informal methods of interpretation. In fact, when given a choice general practitioners would more often choose informal over professional methods of interpretation despite the fact that confidentiality was a significant concern. CONCLUSION: The need for language assistance in consultations with refugees and asylum seekers in Irish general practice is high. General practitioners rely on informal responses. It is necessary to improve knowledge about the organisational contexts that shape general practitioners responses. We also recommend dialogue between general practitioners, patients and interpreters about the relative merits of informal and professional methods of interpretation so that general practitioners\\' choices are responsive to the needs of patients with limited English.

  15. Responses to language barriers in consultations with refugees and asylum seekers: a telephone survey of Irish general practitioners

    Directory of Open Access Journals (Sweden)

    Mosinkie Phillip I

    2008-12-01

    Full Text Available Abstract Background Refugees and asylum seekers experience language barriers in general practice. Qualitative studies have found that responses to language barriers in general practice are ad hoc with use of both professional interpreters and informal interpreters (patients' relatives or friends. However, the scale of the issues involved is unknown. This study quantifies the need for language assistance in general practice consultations and examines the experience of, and satisfaction with, methods of language assistance utilized. Methods Data were collected by telephone survey with general practitioners in a regional health authority in Ireland between July-August 2004. Each respondent was asked a series of questions about consulting with refugees and asylum seekers, the need for language assistance and the kind of language assistance used. Results There was a 70% (n = 56/80 response rate to the telephone survey. The majority of respondents (77% said that they had experienced consultations with refugees and asylum seekers in which language assistance was required. Despite this, general practitioners in the majority of cases managed without an interpreter or used informal methods of interpretation. In fact, when given a choice general practitioners would more often choose informal over professional methods of interpretation despite the fact that confidentiality was a significant concern. Conclusion The need for language assistance in consultations with refugees and asylum seekers in Irish general practice is high. General practitioners rely on informal responses. It is necessary to improve knowledge about the organisational contexts that shape general practitioners responses. We also recommend dialogue between general practitioners, patients and interpreters about the relative merits of informal and professional methods of interpretation so that general practitioners' choices are responsive to the needs of patients with limited English.

  16. [Assessment on the criminal responsibility of drug-induced mental disorders: a questionnaire survey].

    Science.gov (United States)

    Zhang, Sheng-yu; Zhao, Hai; Tang, Tao; Guan, Wei

    2014-12-01

    To understand the assessment on the criminal responsibility of drug-induced mental disorders and judicial experts' opinions. The judicial experts from institutes of forensic psychiatry in Shanghai were selected. They were asked to finish a self-made questionnaire of assessment on the criminal responsibility of drug-induced mental disorders by letters and visits. Most of experts knew the special regulation, "not suitable for evaluation" towards the criminal responsibility of drug-induced mental disorders of the guideline promulgated by Ministry of Justice. Before and after the guideline was issued, no expert made a no-responsibility opinion in such cases. After the guideline was issued, some experts made a full-responsibility or limited-responsibility opinion in such cases. There was a little disagreement among the experts in the case that the crime was unrelated with mental symptoms or the criminals used drugs even though he knew it could induced insanity. But there were still many obvious disagreements among experts in the case that crime was related to such symptoms and person was no ability to debate. Most experts agreed to settle the disagreements with improved legislative perfection. Most experts are not strictly complying with the assessment guidelines during their practice, and there is still an obvious disagreement towards the criminal responsibility of drug-induced mental disorders.

  17. Temperature trend biases

    Science.gov (United States)

    Venema, Victor; Lindau, Ralf

    2016-04-01

    In an accompanying talk we show that well-homogenized national dataset warm more than temperatures from global collections averaged over the region of common coverage. In this poster we want to present auxiliary work about possible biases in the raw observations and on how well relative statistical homogenization can remove trend biases. There are several possible causes of cooling biases, which have not been studied much. Siting could be an important factor. Urban stations tend to move away from the centre to better locations. Many stations started inside of urban areas and are nowadays more outside. Even for villages the temperature difference between the centre and edge can be 0.5°C. When a city station moves to an airport, which often happened around WWII, this takes the station (largely) out of the urban heat island. During the 20th century the Stevenson screen was established as the dominant thermometer screen. This screen protected the thermometer much better against radiation than earlier designs. Deficits of earlier measurement methods have artificially warmed the temperatures in the 19th century. Newer studies suggest we may have underestimated the size of this bias. Currently we are in a transition to Automatic Weather Stations. The net global effect of this transition is not clear at this moment. Irrigation on average decreases the 2m-temperature by about 1 degree centigrade. At the same time, irrigation has increased significantly during the last century. People preferentially live in irrigated areas and weather stations serve agriculture. Thus it is possible that there is a higher likelihood that weather stations are erected in irrigated areas than elsewhere. In this case irrigation could lead to a spurious cooling trend. In the Parallel Observations Science Team of the International Surface Temperature Initiative (ISTI-POST) we are studying influence of the introduction of Stevenson screens and Automatic Weather Stations using parallel measurements

  18. Bias in collegiate courts

    OpenAIRE

    Olowofoyeku, AA

    2016-01-01

    This article addresses the issues attending common law collegiate courts’ engagements with allegations of bias within their own ranks. It will be argued that, in such cases, it would be inappropriate to involve the collegiate panel or any member thereof in the decision, since such involvement inevitably encounters difficulties. The common law’s dilemmas require drastic solutions, but the common law arguably is illequipped to implement the required change. The answer, it will be argued, is ...

  19. Depth of interaction and bias voltage depenence of the spectral response in a pixellated CdTe detector operating in time-over-threshold mode subjected to monochromatic X-rays

    Science.gov (United States)

    Fröjdh, E.; Fröjdh, C.; Gimenez, E. N.; Maneuski, D.; Marchal, J.; Norlin, B.; O'Shea, V.; Stewart, G.; Wilhelm, H.; Modh Zain, R.; Thungström, G.

    2012-03-01

    High stopping power is one of the most important figures of merit for X-ray detectors. CdTe is a promising material but suffers from: material defects, non-ideal charge transport and long range X-ray fluorescence. Those factors reduce the image quality and deteriorate spectral information. In this project we used a monochromatic pencil beam collimated through a 20μm pinhole to measure the detector spectral response in dependance on the depth of interaction. The sensor was a 1mm thick CdTe detector with a pixel pitch of 110μm, bump bonded to a Timepix readout chip operating in Time-Over-Threshold mode. The measurements were carried out at the Extreme Conditions beamline I15 of the Diamond Light Source. The beam was entering the sensor at an angle of \\texttildelow20 degrees to the surface and then passed through \\texttildelow25 pixels before leaving through the bottom of the sensor. The photon energy was tuned to 77keV giving a variation in the beam intensity of about three orders of magnitude along the beam path. Spectra in Time-over-Threshold (ToT) mode were recorded showing each individual interaction. The bias voltage was varied between -30V and -300V to investigate how the electric field affected the spectral information. For this setup it is worth noticing the large impact of fluorescence. At -300V the photo peak and escape peak are of similar height. For high bias voltages the spectra remains clear throughout the whole depth but for lower voltages as -50V, only the bottom part of the sensor carries spectral information. This is an effect of the low hole mobility and the longer range the electrons have to travel in a low field.

  20. Multiple Surveys of Students and Survey Fatigue

    Science.gov (United States)

    Porter, Stephen R.; Whitcomb, Michael E.; Weitzer, William H.

    2004-01-01

    This chapter reviews the literature on survey fatigue and summarizes a research project that indicates that administering multiple surveys in one academic year can significantly suppress response rates in later surveys. (Contains 4 tables.)

  1. Effect on survey response rate of hand written versus printed signature on a covering letter: randomised controlled trial [ISRCTN67566265

    Directory of Open Access Journals (Sweden)

    Ayers Sarah

    2005-08-01

    Full Text Available Abstract Background It is important that response rates to postal surveys are as high as possible to ensure that the results are representative and to maximise statistical power. Previous research has suggested that any personalisation of approach helps to improve the response rate. This experiment tested whether personalising questionnaires by hand signing the covering letter improved the response rate compared with a non-personalised group where the investigator's signature on the covering letter was scanned into the document and printed. Methods Randomised controlled trial. Questionnaires about surgical techniques of caesarean section were mailed to 3,799 Members and Fellows of the Royal College of Obstetricians and Gynaecologists resident in the UK. Individuals were randomly allocated to receive a covering letter with either a computer printed signature or a hand written signature. Two reminders were sent to non-respondents. The outcome measures were the proportion of questionnaires returned and their time to return. Results The response rate was 79.1% (1506/1905 in the hand-signed group and 78.4% (1484/1894 in the scanned and printed signature group. There was no detectable difference between the groups in response rate or time taken to respond. Conclusion No advantage was detected to hand signing the covering letter accompanying a postal questionnaire to health professionals.

  2. Differences in the effects of turns and constrictions on the resistive response in current-biased superconducting wire after single photon absorption

    Science.gov (United States)

    Zotova, A. N.; Y Vodolazov, D.

    2013-07-01

    We study how turns and constrictions affect the resistive response of superconducting wire after instantaneous, localized heating, by modeling the absorption of a single photon by the wire. We find that the presence of constrictions favors the detection of photons with a range of energies whereas the presence of turns increases the ability to detect only relatively ‘low’ energy photons. The main reason is that in the case of a constriction the current density is increased over the whole length and width of the constriction while in the case of a turn the current density is enhanced only near the inner corner of the turn. This results in inhomogeneous Joule heating near the turn and worsens the conditions for the appearance of the normal domain at relatively small currents, where the ‘high’ energy photons could already create a normal domain in the straight part of the wire. We also find that the amplitude of the voltage pulse depends on the location at which the photon is absorbed, being smallest when the photon is absorbed near the turn and largest when the photon is absorbed near the constriction. This effect is due to the difference in the resistance of constrictions and turns in the normal state from the resistance of the rest of the wire.

  3. Neural Correlates of Biased Responses: The Negative Method Effect in the Rosenberg Self-Esteem Scale Is Associated with Right Amygdala Volume.

    Science.gov (United States)

    Wang, Yinan; Kong, Feng; Huang, Lijie; Liu, Jia

    2016-10-01

    Self-esteem is a widely studied construct in psychology that is typically measured by the Rosenberg Self-Esteem Scale (RSES). However, a series of cross-sectional and longitudinal studies have suggested that a simple and widely used unidimensional factor model does not provide an adequate explanation of RSES responses due to method effects. To identify the neural correlates of the method effect, we sought to determine whether and how method effects were associated with the RSES and investigate the neural basis of these effects. Two hundred and eighty Chinese college students (130 males; mean age = 22.64 years) completed the RSES and underwent magnetic resonance imaging (MRI). Behaviorally, method effects were linked to both positively and negatively worded items in the RSES. Neurally, the right amygdala volume negatively correlated with the negative method factor, while the hippocampal volume positively correlated with the general self-esteem factor in the RSES. The neural dissociation between the general self-esteem factor and negative method factor suggests that there are different neural mechanisms underlying them. The amygdala is involved in modulating negative affectivity; therefore, the current study sheds light on the nature of method effects that are related to self-report with a mix of positively and negatively worded items. © 2015 Wiley Periodicals, Inc.

  4. Behavioral Biases in Interpersonal Contexts

    NARCIS (Netherlands)

    N. Liu (Ning)

    2017-01-01

    markdownabstractThis thesis presents evidence suggesting that the same types of biases in individual decision making under uncertainty pertain in interpersonal contexts. The chapters above demonstrate in specific contexts how specific interpersonal factors attenuate, amplify, or replicate these bias

  5. Enhancement of In Vivo and In Vitro Immune Functions by a Conformationally-Biased, Response-Selective Agonist of Human C5a: Implications for a Novel Adjuvant in Vaccine Design

    Science.gov (United States)

    Morgan, Edward L.; Morgan, Brandon N.; Stein, Elisabeth A.; Vitrs, Elizabeth L.; Thoman, Marilyn L.; Sanderson, Sam D.; Phillips, Joy A.

    2009-01-01

    A conformationally-biased, agonist of human C5a65–74 (EP67) was assessed for its adjuvant activities in vitro and in vivo. EP67 induced the release of the inflammatory (Th1) type cytokines from C5a receptor (CD88)-bearing antigen presenting cells (APC). Serum from mice immunized with EP67-ovalbumin (OVA) contained high OVA-specific antibody (Ab) titers [IgG1, IgG2a (IGg2c), IgG2b]. Mice receiving OVA alone produced only IgG1 Abs, indicating the ability of EP67 to induce a Th1-like antibody (A)b class switch. Spleen cell cultures from wild type mice but not CD88−/− mice showed an enhanced OVA-specific proliferative response in vitro. These results indicate the ability of EP67 to drive a Th1-mediated immune response and its potential use as a unique adjuvant PMID:19836478

  6. Ignoring imperfect detection in biological surveys is dangerous: a response to 'fitting and interpreting occupancy models'.

    Directory of Open Access Journals (Sweden)

    Gurutzeta Guillera-Arroita

    Full Text Available In a recent paper, Welsh, Lindenmayer and Donnelly (WLD question the usefulness of models that estimate species occupancy while accounting for detectability. WLD claim that these models are difficult to fit and argue that disregarding detectability can be better than trying to adjust for it. We think that this conclusion and subsequent recommendations are not well founded and may negatively impact the quality of statistical inference in ecology and related management decisions. Here we respond to WLD's claims, evaluating in detail their arguments, using simulations and/or theory to support our points. In particular, WLD argue that both disregarding and accounting for imperfect detection lead to the same estimator performance regardless of sample size when detectability is a function of abundance. We show that this, the key result of their paper, only holds for cases of extreme heterogeneity like the single scenario they considered. Our results illustrate the dangers of disregarding imperfect detection. When ignored, occupancy and detection are confounded: the same naïve occupancy estimates can be obtained for very different true levels of occupancy so the size of the bias is unknowable. Hierarchical occupancy models separate occupancy and detection, and imprecise estimates simply indicate that more data are required for robust inference about the system in question. As for any statistical method, when underlying assumptions of simple hierarchical models are violated, their reliability is reduced. Resorting in those instances where hierarchical occupancy models do no perform well to the naïve occupancy estimator does not provide a satisfactory solution. The aim should instead be to achieve better estimation, by minimizing the effect of these issues during design, data collection and analysis, ensuring that the right amount of data is collected and model assumptions are met, considering model extensions where appropriate.

  7. The relationship between social desirability bias and self-reports of health, substance use, and social network factors among urban substance users in Baltimore, Maryland.

    Science.gov (United States)

    Latkin, Carl A; Edwards, Catie; Davey-Rothwell, Melissa A; Tobin, Karin E

    2017-10-01

    Social desirability response bias may lead to inaccurate self-reports and erroneous study conclusions. The present study examined the relationship between social desirability response bias and self-reports of mental health, substance use, and social network factors among a community sample of inner-city substance users. The study was conducted in a sample of 591 opiate and cocaine users in Baltimore, Maryland from 2009 to 2013. Modified items from the Marlowe-Crowne Social Desirability Scale were included in the survey, which was conducted face-to-face and using Audio Computer Self Administering Interview (ACASI) methods. There were highly statistically significant differences in levels of social desirability response bias by levels of depressive symptoms, drug use stigma, physical health status, recent opiate and cocaine use, Alcohol Use Disorders Identification Test (AUDIT) scores, and size of social networks. There were no associations between health service utilization measures and social desirability bias. In multiple logistic regression models, even after including the Center for Epidemiologic Studies Depression Scale (CES-D) as a measure of depressive symptomology, social desirability bias was associated with recent drug use and drug user stigma. Social desirability bias was not associated with enrollment in prior research studies. These findings suggest that social desirability bias is associated with key health measures and that the associations are not primarily due to depressive symptoms. Methods are needed to reduce social desirability bias. Such methods may include the wording and prefacing of questions, clearly defining the role of "study participant," and assessing and addressing motivations for socially desirable responses. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Flagstaff Robotic Survey Telescope (FRoST): Rapid Response for NEOs

    Science.gov (United States)

    Avner, Louis Daniel; Trilling, David E.; Dunham, Edward W.

    2016-10-01

    The Flagstaff Robotic Survey Telescope (FRoST) is a robotic 0.6m Schmidt telescope that will be used for instant follow-up observations of newly discovered Near Earth Objects (NEOs). Here, we present the progress being made on FRoST as well as the remaining tasks until the telescope is fully operational. With more than one thousand NEOs being found yearly, more telescopes are needed to carry out follow-up observations. Most NEOs are found at their peak brightness, meaning that these observations need to happen quickly before they fade. By using the Catalina Sky Survey Queue Manager, FRoST will be able to accept interruptions during the night and prioritize observations automatically, allowing instant follow-up observations. FRoST will help refine the orbit of these newly discovered objects while providing optical colors. We will ingest information from the NEOCP and JPL's Scout program at five minute intervals and observe newly discovered targets robotically, process the data automatically, and autonomously generate astrometry and colors. We estimate that will we provide essentially 100% recovery of objects brighter than V~20. This work was supported by the NSF MRI program as well as by NAU and Lowell Observatory.

  9. Small business needs assessment: a comparison of dental educators' responses with SBDC survey results.

    Science.gov (United States)

    Comer, R W; Callan, R S; Blalock, J S; Turner, J E; Trombly, R M

    2001-09-01

    A primary focus of dental education is to teach students the knowledge, skills, and values essential for practicing dentistry. However, the preparation of dentists to manage a business is frequently cited as inadequate. A survey was prepared to assess teachers' opinions of business instructional topics: challenges; desired training; employee benefits; learning resources; importance of business topics; and appropriateness of time allocations. The purpose of this project is to compare opinions of teachers of dental practice management with key management aspects reported for service businesses by the Small Business Development Center (SBDC). Practice management teachers from forty-eight (89 percent) schools responded to the survey. They indicated that several challenges confronting dentists are similar to other service businesses. Dentists, however, rank customer relations appreciably higher. In order of importance of teaching topics, the practice management teachers rank ethics and personnel management as a high priority and planning as a low priority. Awareness of the similarities and differences in the perceptions of practice management teachers and businesspeople may result in instructional improvements.

  10. Extrinsic control of the exchange bias

    Energy Technology Data Exchange (ETDEWEB)

    Hochstrat, A.; Binek, Ch. E-mail: binek@kleemann.uni-duisburg.de; Chen Xi; Kleemann, W

    2004-05-01

    A new control mechanism for the exchange bias effect in magnetic heterostructures is proposed. It takes advantage of the magnetoelectric effect which takes place in the antiferromagnetic pinning layer. In contrast with the pioneering AC measurements of the magnetoelectric effect, we investigate the magnetic response of the prototypical magnetoelectric compound Cr{sub 2}O{sub 3} on static electric fields. The linear dependence of the magnetic moment on the applied axial electric field and the temperature dependence of the corresponding slopes {alpha}{sub parallel} are measured by DC SQUID magnetometry. The contribution of the field-induced surface magnetization and its impact on the exchange bias effect is estimated.

  11. On Inferring Demand for Health Care in the Presence of Anchoring, Acquiescence, and Selection Biases

    OpenAIRE

    Jay Bhattacharya; Adam Isen

    2008-01-01

    In the contingent valuation literature, both anchoring and acquiescence biases pose problems when using an iterative bidding game to infer willingness to pay. Anchoring bias occurs when the willingness to pay estimate is sensitive to the initially presented starting value. Acquiescence bias occurs when survey respondents exhibit a tendency to answer 'yes' to questions, regardless of their true preferences. More generally, whenever a survey format is used and not all of those contacted partici...

  12. Assessing Bias in Search Engines.

    Science.gov (United States)

    Mowshowitz, Abbe; Kawaguchi, Akira

    2002-01-01

    Addresses the measurement of bias in search engines on the Web, defining bias as the balance and representation of items in a collection retrieved from a database for a set of queries. Assesses bias by measuring the deviation from the ideal of the distribution produced by a particular search engine. (Author/LRW)

  13. Relapsing-remitting multiple sclerosis: patterns of response to disease-modifying therapies and associated factors: a national survey.

    Science.gov (United States)

    Sá, Maria José; de Sá, João; Sousa, Lívia

    2014-12-01

    Current treatments for relapsing-remitting multiple sclerosis (RRMS) are only partially effective. The objective of this study was to characterize treatment response in RRMS patients in Portugal to 12-month therapy with first-line disease-modifying therapies. In this retrospective study, neurologists at participating centers completed survey questionnaires using records of patients with RRMS who had received first-line treatment with one of five European Medicine Agency-approved agents in the 12 months prior to inclusion in the survey. Sub-optimal responders included patients treated for at least 1 year, and who had ≥1 relapse(s) or an increase of 1.5 points on the Expanded Disability Status Scale (EDSS; if baseline EDSS was 0) or an increase of ≥0.5 points (baseline EDSS ≥1). Optimal responders included patients treated for at least 1 year without relapse and who had an increase of EDSS (if baseline EDSS was 0) or no increase in EDSS (baseline EDSS ≥1). Data for 1,131 patients from 15 centers were analyzed. Twenty-six percent (95% confidence interval 23-28%) of patients had sub-optimal treatment response. Duration of therapy (P EDSS score (P EDSS score at baseline and did not differ among therapies. Neurologists should closely monitor patients to optimize treatment strategies and better control disease, improving prognosis.

  14. When bias binds: Effect of implicit outgroup bias on ingroup affiliation.

    Science.gov (United States)

    Jacoby-Senghor, Drew S; Sinclair, Stacey; Smith, Colin Tucker

    2015-09-01

    We tested a novel process we term implicit homophily in which perceivers' implicit outgroup bias shapes their affiliative responses toward ingroup targets with outgroup friends as a function of perceived similarity. Across 4 studies, we tested implicit homophily in the context of racial groups. We found that White participants with higher implicit anti-Black bias reported less affiliative responses toward White targets with Black friends compared with White targets with White friends, and this effect persisted above and beyond the effects of implicit pro-White bias and explicit racial bias (Studies 1-3). We further found evidence that this relationship between implicit anti-Black bias and affiliation exists because participants infer how comfortable targets are around outgroup members (Preliminary Study) and use this information to infer similarity on this dimension (Studies 1-3). Our findings also suggested that stigma transference and expectancy violation were not viable alternative mediators (Preliminary Study and Study 1). Finally, women's implicit anti-Black bias predicted their likelihood of having Facebook friends with Black friends, providing ecological and behavioral evidence of implicit homophily (Study 4). Implications for research on stigma by association, extended contact, affiliation, and network formation are discussed.

  15. Contextual modulation of biases in face recognition.

    Directory of Open Access Journals (Sweden)

    Fatima Maria Felisberti

    Full Text Available BACKGROUND: The ability to recognize the faces of potential cooperators and cheaters is fundamental to social exchanges, given that cooperation for mutual benefit is expected. Studies addressing biases in face recognition have so far proved inconclusive, with reports of biases towards faces of cheaters, biases towards faces of cooperators, or no biases at all. This study attempts to uncover possible causes underlying such discrepancies. METHODOLOGY AND FINDINGS: Four experiments were designed to investigate biases in face recognition during social exchanges when behavioral descriptors (prosocial, antisocial or neutral embedded in different scenarios were tagged to faces during memorization. Face recognition, measured as accuracy and response latency, was tested with modified yes-no, forced-choice and recall tasks (N = 174. An enhanced recognition of faces tagged with prosocial descriptors was observed when the encoding scenario involved financial transactions and the rules of the social contract were not explicit (experiments 1 and 2. Such bias was eliminated or attenuated by making participants explicitly aware of "cooperative", "cheating" and "neutral/indifferent" behaviors via a pre-test questionnaire and then adding such tags to behavioral descriptors (experiment 3. Further, in a social judgment scenario with descriptors of salient moral behaviors, recognition of antisocial and prosocial faces was similar, but significantly better than neutral faces (experiment 4. CONCLUSION: The results highlight the relevance of descriptors and scenarios of social exchange in face recognition, when the frequency of prosocial and antisocial individuals in a group is similar. Recognition biases towards prosocial faces emerged when descriptors did not state the rules of a social contract or the moral status of a behavior, and they point to the existence of broad and flexible cognitive abilities finely tuned to minor changes in social context.

  16. Cigarette demand is responsive to higher prices: findings from a survey of University students in Jordan.

    Science.gov (United States)

    Sweis, Nadia J; Cherukupalli, Rajeev

    2016-11-01

    To estimate the price elasticity of cigarette demand for university students aged 18-24 years in Jordan. Questions from the Global Adult Tobacco Survey were adapted and administered to students from 10 public universities in Jordan in 2014. A two-part econometric model of cigarette demand was estimated. Nearly one-third of university students in Jordan smoke, purchasing 33.2 packs per month and paying 1.70 Jordanian dinars on average (US$2.40) for a pack of 20 cigarettes. The price elasticity of cigarette demand was estimated to be -1.15. Higher taxes may be particularly effective in reducing smoking among University students in Jordan. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  17. Unconscious race and class bias: its association with decision making by trauma and acute care surgeons.

    Science.gov (United States)

    Haider, Adil H; Schneider, Eric B; Sriram, N; Dossick, Deborah S; Scott, Valerie K; Swoboda, Sandra M; Losonczy, Lia; Haut, Elliott R; Efron, David T; Pronovost, Peter J; Freischlag, Julie A; Lipsett, Pamela A; Cornwell, Edward E; MacKenzie, Ellen J; Cooper, Lisa A

    2014-09-01

    Recent studies have found that unconscious biases may influence physicians' clinical decision making. The objective of our study was to determine, using clinical vignettes, if unconscious race and class biases exist specifically among trauma/acute care surgeons and, if so, whether those biases impact surgeons' clinical decision making. A prospective Web-based survey was administered to active members of the Eastern Association for the Surgery of Trauma. Participants completed nine clinical vignettes, each with three trauma/acute care surgery management questions. Race Implicit Association Test (IAT) and social class IAT assessments were completed by each participant. Multivariable, ordered logistic regression analysis was then used to determine whether implicit biases reflected on the IAT tests were associated with vignette responses. In total, 248 members of the Eastern Association for the Surgery of Trauma participated. Of these, 79% explicitly stated that they had no race preferences and 55% stated they had no social class preferences. However, 73.5% of the participants had IAT scores demonstrating an unconscious preference toward white persons; 90.7% demonstrated an implicit preference toward upper social class persons. Only 2 of 27 vignette-based clinical decisions were associated with patient race or social class on univariate analyses. Multivariable analyses revealed no relationship between IAT scores and vignette-based clinical assessments. Unconscious preferences for white and upper-class persons are prevalent among trauma and acute care surgeons. In this study, these biases were not statistically significantly associated with clinical decision making. Further study of the factors that may prevent implicit biases from influencing patient management is warranted. Epidemiologic study, level II.

  18. Sex-biased dispersal of human ancestors.

    Science.gov (United States)

    Sugiyama, Yukimaru

    2017-07-01

    Some anthropologists and primatologists have argued that, judging by extant chimpanzees and humans, which are female-biased dispersers, the common ancestors of humans and chimpanzees were also female-biased dispersers. It has been thought that sex-biased dispersal patterns have been genetically transmitted for millions of years. However, this character has changed many times with changes in environment and life-form during human evolution and historical times. I examined life-form and social organization of nonhuman primates, among them gatherers (foragers), hunter-gatherers, agriculturalists, industrialists, and modern and extant humans. I conclude that dispersal patterns changed in response to environmental conditions during primate and human evolution. © 2017 Wiley Periodicals, Inc.

  19. Reciprocity-induced bias in digital reputation

    CERN Document Server

    Livan, Giacomo; Aste, Tomaso

    2016-01-01

    The peer-to-peer (P2P) economy relies on establishing trust in distributed networked systems, where the reliability of a user is assessed through digital peer-review processes that aggregate ratings into reputation scores. Here we present evidence of a network effect which biases the digital reputations of the users of P2P networks, showing that P2P networks display exceedingly high levels of reciprocity. In fact, these are so large that they are close to the highest levels structurally compatible with the networks' reputation landscape. This shows that the crowdsourcing process underpinning digital reputation is significantly distorted by the attempt of users to mutually boost reputation, or to retaliate, through the exchange of ratings. We show that the least active users are predominantly responsible for such reciprocity-induced bias, and that this fact can be exploited to suppress the bias itself.

  20. Linearity Limits of Biased 1337 Trap Detectors

    CERN Document Server

    Balling, Petr

    2015-01-01

    The upper power limit of linear response of light trap detectors was recently measured [2,3]. We have completed this measurement with test of traps with bias voltage at several visible wavelengths using silicon photodiodes Hamamatsu S1337 1010 and made a brief test of S5227 1010. Bias extends the linearity limit by factor of more than 10 for very narrow beams and more than 30 for wide beams [5]. No irreversible changes were detected even for the highest irradiance of 33 W/cm2 at 406nm. Here we present measurement of minimal bias voltage necessary for 99%, 99.8% and 99.95% linearity for several beam sizes.