WorldWideScience

Sample records for test bias research

  1. Bias against research on gender bias.

    Science.gov (United States)

    Cislak, Aleksandra; Formanowicz, Magdalena; Saguy, Tamar

    2018-01-01

    The bias against women in academia is a documented phenomenon that has had detrimental consequences, not only for women, but also for the quality of science. First, gender bias in academia affects female scientists, resulting in their underrepresentation in academic institutions, particularly in higher ranks. The second type of gender bias in science relates to some findings applying only to male participants, which produces biased knowledge. Here, we identify a third potentially powerful source of gender bias in academia: the bias against research on gender bias. In a bibliometric investigation covering a broad range of social sciences, we analyzed published articles on gender bias and race bias and established that articles on gender bias are funded less often and published in journals with a lower Impact Factor than articles on comparable instances of social discrimination. This result suggests the possibility of an underappreciation of the phenomenon of gender bias and related research within the academic community. Addressing this meta-bias is crucial for the further examination of gender inequality, which severely affects many women across the world.

  2. Latent Trait Theory Applications to Test Item Bias Methodology. Research Memorandum No. 1.

    Science.gov (United States)

    Osterlind, Steven J.; Martois, John S.

    This study discusses latent trait theory applications to test item bias methodology. A real data set is used in describing the rationale and application of the Rasch probabilistic model item calibrations across various ethnic group populations. A high school graduation proficiency test covering reading comprehension, writing mechanics, and…

  3. Design-related bias in estimates of accuracy when comparing imaging tests: examples from breast imaging research

    International Nuclear Information System (INIS)

    Houssami, Nehmat; Ciatto, Stefano

    2010-01-01

    This work highlights concepts on the potential for design-related factors to bias estimates of test accuracy in comparative imaging research. We chose two design factors, selection of eligible subjects and the reference standard, to examine the effect of design limitations on estimates of accuracy. Estimates of sensitivity in a study of the comparative accuracy of mammography and ultrasound differed according to how subjects were selected. Comparison of a new imaging test with an existing test should distinguish whether the new test is to be used as a replacement for, or as an adjunct to, the conventional test, to guide the method for subject selection. Quality of the reference standard, examined in a meta-analysis of preoperative breast MRI, varied across studies and was associated with estimates of incremental accuracy. Potential solutions to deal with the reference standard are outlined where an ideal reference standard may not be available in all subjects. These examples of breast imaging research demonstrate that design-related bias, when comparing a new imaging test with a conventional imaging test, may bias accuracy in a direction that favours the new test by overestimating the accuracy of the new test or by underestimating that of the conventional test. (orig.)

  4. Measuring the bias against low-income country research: an Implicit Association Test.

    Science.gov (United States)

    Harris, Matthew; Macinko, James; Jimenez, Geronimo; Mullachery, Pricila

    2017-11-06

    With an increasing array of innovations and research emerging from low-income countries there is a growing recognition that even high-income countries could learn from these contexts. It is well known that the source of a product influences perception of that product, but little research has examined whether this applies also in evidence-based medicine and decision-making. In order to examine likely barriers to learning from low-income countries, this study uses established methods in cognitive psychology to explore whether healthcare professionals and researchers implicitly associate good research with rich countries more so than with poor countries. Computer-based Implicit Association Test (IAT) distributed to healthcare professionals and researchers. Stimuli representing Rich Countries were chosen from OECD members in the top ten (>$36,000 per capita) World Bank rankings and Poor Countries were chosen from the bottom thirty (based medicine and diffusion of innovations.

  5. Bias in clinical intervention research

    DEFF Research Database (Denmark)

    Gluud, Lise Lotte

    2006-01-01

    Research on bias in clinical trials may help identify some of the reasons why investigators sometimes reach the wrong conclusions about intervention effects. Several quality components for the assessment of bias control have been suggested, but although they seem intrinsically valid, empirical...... evidence is needed to evaluate their effects on the extent and direction of bias. This narrative review summarizes the findings of methodological studies on the influence of bias in clinical trials. A number of methodological studies suggest that lack of adequate randomization in published trial reports...

  6. Addressing criticisms of existing predictive bias research: cognitive ability test scores still overpredict African Americans' job performance.

    Science.gov (United States)

    Berry, Christopher M; Zhao, Peng

    2015-01-01

    Predictive bias studies have generally suggested that cognitive ability test scores overpredict job performance of African Americans, meaning these tests are not predictively biased against African Americans. However, at least 2 issues call into question existing over-/underprediction evidence: (a) a bias identified by Aguinis, Culpepper, and Pierce (2010) in the intercept test typically used to assess over-/underprediction and (b) a focus on the level of observed validity instead of operational validity. The present study developed and utilized a method of assessing over-/underprediction that draws on the math of subgroup regression intercept differences, does not rely on the biased intercept test, allows for analysis at the level of operational validity, and can use meta-analytic estimates as input values. Therefore, existing meta-analytic estimates of key parameters, corrected for relevant statistical artifacts, were used to determine whether African American job performance remains overpredicted at the level of operational validity. African American job performance was typically overpredicted by cognitive ability tests across levels of job complexity and across conditions wherein African American and White regression slopes did and did not differ. Because the present study does not rely on the biased intercept test and because appropriate statistical artifact corrections were carried out, the present study's results are not affected by the 2 issues mentioned above. The present study represents strong evidence that cognitive ability tests generally overpredict job performance of African Americans. (c) 2015 APA, all rights reserved.

  7. Sampling bias in climate-conflict research

    Science.gov (United States)

    Adams, Courtland; Ide, Tobias; Barnett, Jon; Detges, Adrien

    2018-03-01

    Critics have argued that the evidence of an association between climate change and conflict is flawed because the research relies on a dependent variable sampling strategy1-4. Similarly, it has been hypothesized that convenience of access biases the sample of cases studied (the `streetlight effect'5). This also gives rise to claims that the climate-conflict literature stigmatizes some places as being more `naturally' violent6-8. Yet there has been no proof of such sampling patterns. Here we test whether climate-conflict research is based on such a biased sample through a systematic review of the literature. We demonstrate that research on climate change and violent conflict suffers from a streetlight effect. Further, studies which focus on a small number of cases in particular are strongly informed by cases where there has been conflict, do not sample on the independent variables (climate impact or risk), and hence tend to find some association between these two variables. These biases mean that research on climate change and conflict primarily focuses on a few accessible regions, overstates the links between both phenomena and cannot explain peaceful outcomes from climate change. This could result in maladaptive responses in those places that are stigmatized as being inherently more prone to climate-induced violence.

  8. Is there gender bias in nursing research?

    Science.gov (United States)

    Polit, Denise F; Beck, Cheryl Tatano

    2008-10-01

    Using data from a consecutive sample of 259 studies published in four leading nursing research journals in 2005-2006, we examined whether nurse researchers favor females as study participants. On average, 75.3% of study participants were female, and 38% of studies had all-female samples. The bias favoring female participants was statistically significant and persistent. The bias was observed regardless of funding source, methodological features, and other participant and researcher characteristics, with one exception: studies that had male investigators had more sex-balanced samples. When designing studies, nurse researchers need to pay close attention to who will benefit from their research and to whether they are leaving out a specific group about which there is a gap in knowledge. (c) 2008 Wiley Periodicals, Inc.

  9. Research bias in judgement bias studies : a systematic review of valuation judgement literature

    NARCIS (Netherlands)

    Vincent Gruis; Pim Klamer; Cok Bakker

    2017-01-01

    Valuation judgement bias has been a research topic for several years due to its proclaimed effect on valuation accuracy. However, little is known on the emphasis of literature on judgement bias, with regard to, for instance, research methodologies, research context and robustness of research

  10. Research bias in judgement bias studies : A systematic review of valuation judgement literature

    NARCIS (Netherlands)

    Klamer, Pim; Bakker, C.; Gruis, Vincent

    2017-01-01

    Valuation judgement bias has been a research topic for several years due to its proclaimed effect on valuation accuracy. However, little is known on the emphasis of literature on judgement bias, with regard to, for instance, research methodologies, research context and robustness of research

  11. Cognitive bias test as a tool for accessing fish welfare

    Directory of Open Access Journals (Sweden)

    Krzysztof Wojtas

    2015-12-01

    Difference in behaviour during the cognitive bias test suggests that fish cognitive bias can be affected by living conditions. Therefore this type of test should be taken to consideration as a tool in further fish welfare studies. It can be especially useful in studies concerning influence of living conditions that cannot be examined in direct way for example by preference test.

  12. Avoiding bias in safety testing design

    DEFF Research Database (Denmark)

    Calow, Peter

    2011-01-01

    All scientists are biased, no matter what their backgrounds or affiliations, so what is it about the scientific method that overcomes this and which makes science so successful? Key features are transparency and critical peer scrutiny. These general issues will be will be considered in terms...

  13. Awareness and minimisation of systematic bias in research.

    LENUS (Irish Health Repository)

    Malone, Helen

    2014-03-01

    A major goal of nursing and midwifery is the delivery of evidence-based practice. Consequently, it is essential for the quality and safety of patient\\/client care that policy makers, educators and practitioners are aware of the presence of potential systematic bias in research practice and research publications so that only sound evidence translates into practice. The main aim of this paper is to highlight the need for ongoing awareness of the potential presence of systematic bias in research practice, to explore commonly reported types of systematic bias and to report some methods that can be applied to minimise systematic bias in research.

  14. Implicit Messages:A Review of "Bias in Mental Testing."

    Science.gov (United States)

    Scarr, Sandra

    1981-01-01

    Reviews Arthur Jensen's "Bias in Mental Testing" in terms of its implications for racial genetic inferiority, and offers alternate explanations for racial differences in testing based on data from studies on Black socialization and cultural differences in child rearing. (CM)

  15. Racial Bias and Predictive Validity in Testing for Selection.

    Science.gov (United States)

    1983-07-01

    the inequa - lity rR (P.C) *0 (2) must define test bias. This definition of test bias conforms to the requirements of the Civil Rights Act of 1964 as...of Educational Measurement, 1976, 13, 43-52. Einhorn, H. J., & Bass, A. R. Methodological considerations relevant to discrimination in employment ...34unbiased" selec- tion model: A question of utilities. Journal of Applied Psychology, 1975, 60, 345-351. Guion, R. M. Employment tests and discriminatory

  16. Empirical Comparison of Publication Bias Tests in Meta-Analysis.

    Science.gov (United States)

    Lin, Lifeng; Chu, Haitao; Murad, Mohammad Hassan; Hong, Chuan; Qu, Zhiyong; Cole, Stephen R; Chen, Yong

    2018-04-16

    Decision makers rely on meta-analytic estimates to trade off benefits and harms. Publication bias impairs the validity and generalizability of such estimates. The performance of various statistical tests for publication bias has been largely compared using simulation studies and has not been systematically evaluated in empirical data. This study compares seven commonly used publication bias tests (i.e., Begg's rank test, trim-and-fill, Egger's, Tang's, Macaskill's, Deeks', and Peters' regression tests) based on 28,655 meta-analyses available in the Cochrane Library. Egger's regression test detected publication bias more frequently than other tests (15.7% in meta-analyses of binary outcomes and 13.5% in meta-analyses of non-binary outcomes). The proportion of statistically significant publication bias tests was greater for larger meta-analyses, especially for Begg's rank test and the trim-and-fill method. The agreement among Tang's, Macaskill's, Deeks', and Peters' regression tests for binary outcomes was moderately strong (most κ's were around 0.6). Tang's and Deeks' tests had fairly similar performance (κ > 0.9). The agreement among Begg's rank test, the trim-and-fill method, and Egger's regression test was weak or moderate (κ < 0.5). Given the relatively low agreement between many publication bias tests, meta-analysts should not rely on a single test and may apply multiple tests with various assumptions. Non-statistical approaches to evaluating publication bias (e.g., searching clinical trials registries, records of drug approving agencies, and scientific conference proceedings) remain essential.

  17. Multiple Sources of Test Bias on the WISC-R and Bender-Gestalt Test.

    Science.gov (United States)

    Oakland, Thomas; Feigenbaum, David

    1979-01-01

    Assessed test bias on the Wechsler Intelligence Test for Children-Revised (WISC-R) and Bender-Gestalt. On the Bender, evidence of bias was infrequent and irregular. On the WISC-R, group differences were most discernible for age, sex, family structure, and race. Consistent patterns of bias were not apparent among comparison groups. (Author)

  18. Opportunity to Learn, Test Bias, and School Effects.

    Science.gov (United States)

    Anderson, Lorin W.

    The purpose of the study was to examine test bias and the "non-effects" of schooling. Teachers were given a list of words selected from standardized vocabulary tests and asked to indicate the words they had taught. The words were classified by the grade level at which they were first introduced. Ninety-five third-grade students in four schools…

  19. Resisting Age Bias in Digital Literacy Research

    Science.gov (United States)

    Bowen, Lauren Marshall

    2011-01-01

    Through an eighty-one-year-old woman's literacy narrative, I argue that literacy researchers should pay greater attention to elder writers, readers, and learners. Particularly as notions of literacy shift in digital times, the perspective of a lifespan can reveal otherwise hidden complexities of literacy, including the motivational impact of…

  20. Demand artifact: objectively detecting biased participants in advertising research.

    Science.gov (United States)

    Miller, Felicia; Schertzer, Susan

    2014-12-01

    Detecting and reducing the effect of biased participants continues to be an important task for researchers. However, the lack of objective measures to assess demand artifact has made it difficult to effectively address this issue. This paper reports two experiments that apply a theory-based post-experimental inquiry that can systematically identify biased participants in consumer research. The results demonstrate how easily and effectively researchers can incorporate this tool into experimental studies of all types and reduce the likelihood of systematic error.

  1. Attention, interpretation, and memory biases in subclinical depression: a proof-of-principle test of the combined cognitive biases hypothesis.

    Science.gov (United States)

    Everaert, Jonas; Duyck, Wouter; Koster, Ernst H W

    2014-04-01

    Emotional biases in attention, interpretation, and memory are viewed as important cognitive processes underlying symptoms of depression. To date, there is a limited understanding of the interplay among these processing biases. This study tested the dependence of memory on depression-related biases in attention and interpretation. Subclinically depressed and nondepressed participants completed a computerized version of the scrambled sentences test (measuring interpretation bias) while their eye movements were recorded (measuring attention bias). This task was followed by an incidental free recall test of previously constructed interpretations (measuring memory bias). Path analysis revealed a good fit for the model in which selective orienting of attention was associated with interpretation bias, which in turn was associated with a congruent bias in memory. Also, a good fit was observed for a path model in which biases in the maintenance of attention and interpretation were associated with memory bias. Both path models attained a superior fit compared with path models without the theorized functional relations among processing biases. These findings enhance understanding of how mechanisms of attention and interpretation regulate what is remembered. As such, they offer support for the combined cognitive biases hypothesis or the notion that emotionally biased cognitive processes are not isolated mechanisms but instead influence each other. Implications for theoretical models and emotion regulation across the spectrum of depressive symptoms are discussed.

  2. Lost in translation: Review of identification bias, translation bias and research waste in dentistry.

    Science.gov (United States)

    Layton, Danielle M; Clarke, Michael

    2016-01-01

    To review how articles are retrieved from bibliographic databases, what article identification and translation problems have affected research, and how these problems can contribute to research waste and affect clinical practice. This literature review sought and appraised articles regarding identification- and translation-bias in the medical and dental literature, which limit the ability of users to find research articles and to use these in practice. Articles can be retrieved from bibliographic databases by performing a word or index-term (for example, MeSH for MEDLINE) search. Identification of articles is challenging when it is not clear which words are most relevant, and which terms have been allocated to indexing fields. Poor reporting quality of abstracts and articles has been reported across the medical literature at large. Specifically in dentistry, research regarding time-to-event survival analyses found the allocation of MeSH terms to be inconsistent and inaccurate, important words were omitted from abstracts by authors, and the quality of reporting in the body of articles was generally poor. These shortcomings mean that articles will be difficult to identify, and difficult to understand if found. Use of specialized electronic search strategies can decrease identification bias, and use of tailored reporting guidelines can decrease translation bias. Research that cannot be found, or cannot be used results in research waste, and undermines clinical practice. Identification- and translation-bias have been shown to affect time-to-event dental articles, are likely affect other fields of research, and are largely unrecognized by authors and evidence seekers alike. By understanding that the problems exist, solutions can be sought to improve identification and translation of our research. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  3. Sniffing out the Secret Poison: Selection Bias in Educational Research

    Science.gov (United States)

    Showalter, Daniel A.; Mullet, Luke B.

    2017-01-01

    Selection bias is a persistent, and often hidden, problem in educational research. It is the primary obstacle standing in between increasingly available large education datasets and the ability to make valid causal inferences to inform policymaking, research, and practice (Stuart, 2010). This article provides an accessible discussion on the…

  4. Bias-Free Chemically Diverse Test Sets from Machine Learning.

    Science.gov (United States)

    Swann, Ellen T; Fernandez, Michael; Coote, Michelle L; Barnard, Amanda S

    2017-08-14

    Current benchmarking methods in quantum chemistry rely on databases that are built using a chemist's intuition. It is not fully understood how diverse or representative these databases truly are. Multivariate statistical techniques like archetypal analysis and K-means clustering have previously been used to summarize large sets of nanoparticles however molecules are more diverse and not as easily characterized by descriptors. In this work, we compare three sets of descriptors based on the one-, two-, and three-dimensional structure of a molecule. Using data from the NIST Computational Chemistry Comparison and Benchmark Database and machine learning techniques, we demonstrate the functional relationship between these structural descriptors and the electronic energy of molecules. Archetypes and prototypes found with topological or Coulomb matrix descriptors can be used to identify smaller, statistically significant test sets that better capture the diversity of chemical space. We apply this same method to find a diverse subset of organic molecules to demonstrate how the methods can easily be reapplied to individual research projects. Finally, we use our bias-free test sets to assess the performance of density functional theory and quantum Monte Carlo methods.

  5. Examining publication bias—a simulation-based evaluation of statistical tests on publication bias

    Directory of Open Access Journals (Sweden)

    Andreas Schneck

    2017-11-01

    Full Text Available Background Publication bias is a form of scientific misconduct. It threatens the validity of research results and the credibility of science. Although several tests on publication bias exist, no in-depth evaluations are available that examine which test performs best for different research settings. Methods Four tests on publication bias, Egger’s test (FAT, p-uniform, the test of excess significance (TES, as well as the caliper test, were evaluated in a Monte Carlo simulation. Two different types of publication bias and its degree (0%, 50%, 100% were simulated. The type of publication bias was defined either as file-drawer, meaning the repeated analysis of new datasets, or p-hacking, meaning the inclusion of covariates in order to obtain a significant result. In addition, the underlying effect (β = 0, 0.5, 1, 1.5, effect heterogeneity, the number of observations in the simulated primary studies (N = 100, 500, and the number of observations for the publication bias tests (K = 100, 1,000 were varied. Results All tests evaluated were able to identify publication bias both in the file-drawer and p-hacking condition. The false positive rates were, with the exception of the 15%- and 20%-caliper test, unbiased. The FAT had the largest statistical power in the file-drawer conditions, whereas under p-hacking the TES was, except under effect heterogeneity, slightly better. The CTs were, however, inferior to the other tests under effect homogeneity and had a decent statistical power only in conditions with 1,000 primary studies. Discussion The FAT is recommended as a test for publication bias in standard meta-analyses with no or only small effect heterogeneity. If two-sided publication bias is suspected as well as under p-hacking the TES is the first alternative to the FAT. The 5%-caliper test is recommended under conditions of effect heterogeneity and a large number of primary studies, which may be found if publication bias is examined in a

  6. An experimental investigation of recruitment bias in eating pathology research.

    Science.gov (United States)

    Moss, Erin L; von Ranson, Kristin M

    2006-04-01

    Previous, uncontrolled research has suggested a bias may exist in recruiting participants for eating disorder research. Recruitment biases may affect sample representativeness and generalizability of findings. This experiment investigated whether revealing that a study's topic was related to eating disorders created a self-selection bias. Young women at a university responded to advertisements containing contrasting information about the nature of a single study. We recruited one group by advertising the study under the title "Disordered Eating in Young Women" (n = 251) and another group using the title "Consumer Preferences" (n = 259). Results indicated similar levels of eating pathology in both groups, so the different recruitment techniques did not engender self-selection. However, the consumer preferences group scored higher in self-reported social desirability. The level of information conveyed in study advertising does not impact reporting of eating disturbances among nonclinical samples, although there is evidence social desirability might. 2006 by Wiley Periodicals, Inc.

  7. Further exploration of dissemination bias in qualitative research required to facilitate assessment within qualitative evidence syntheses.

    Science.gov (United States)

    Toews, Ingrid; Booth, Andrew; Berg, Rigmor C; Lewin, Simon; Glenton, Claire; Munthe-Kaas, Heather M; Noyes, Jane; Schroter, Sara; Meerpohl, Joerg J

    2017-08-01

    To conceptualise and discuss dissemination bias in qualitative research. It is likely that the mechanisms leading to dissemination bias in quantitative research, including time lag, language, gray literature, and truncation bias also contribute to dissemination bias in qualitative research. These conceptual considerations have informed the development of a research agenda. Further exploration of dissemination bias in qualitative research is needed, including the extent of non-dissemination and related dissemination bias, and how to assess dissemination bias within qualitative evidence syntheses. We also need to consider the mechanisms through which dissemination bias in qualitative research could occur to explore approaches for reducing it. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Dutch research funding, gender bias, and Simpson’s paradox

    NARCIS (Netherlands)

    Albers, Casper J.

    2015-01-01

    Based on, among other criteria, three consecutive years of grant applications to the “Veni programme” of the Netherlands Organization for Scientific Research (NWO), van der Lee and Ellemers (1) conclude that these data “provide compelling evidence of gender bias in personal grant applications to

  9. Reporting bias in medical research - a narrative review

    Directory of Open Access Journals (Sweden)

    Kölsch Heike

    2010-04-01

    Full Text Available Abstract Reporting bias represents a major problem in the assessment of health care interventions. Several prominent cases have been described in the literature, for example, in the reporting of trials of antidepressants, Class I anti-arrhythmic drugs, and selective COX-2 inhibitors. The aim of this narrative review is to gain an overview of reporting bias in the medical literature, focussing on publication bias and selective outcome reporting. We explore whether these types of bias have been shown in areas beyond the well-known cases noted above, in order to gain an impression of how widespread the problem is. For this purpose, we screened relevant articles on reporting bias that had previously been obtained by the German Institute for Quality and Efficiency in Health Care in the context of its health technology assessment reports and other research work, together with the reference lists of these articles. We identified reporting bias in 40 indications comprising around 50 different pharmacological, surgical (e.g. vacuum-assisted closure therapy, diagnostic (e.g. ultrasound, and preventive (e.g. cancer vaccines interventions. Regarding pharmacological interventions, cases of reporting bias were, for example, identified in the treatment of the following conditions: depression, bipolar disorder, schizophrenia, anxiety disorder, attention-deficit hyperactivity disorder, Alzheimer's disease, pain, migraine, cardiovascular disease, gastric ulcers, irritable bowel syndrome, urinary incontinence, atopic dermatitis, diabetes mellitus type 2, hypercholesterolaemia, thyroid disorders, menopausal symptoms, various types of cancer (e.g. ovarian cancer and melanoma, various types of infections (e.g. HIV, influenza and Hepatitis B, and acute trauma. Many cases involved the withholding of study data by manufacturers and regulatory agencies or the active attempt by manufacturers to suppress publication. The ascertained effects of reporting bias included the

  10. TEST BIAS--VALIDITY OF THE SCHOLASTIC APTITUDE TEST FOR NEGRO AND WHITE STUDENTS IN INTEGRATED COLLEGES.

    Science.gov (United States)

    CLEARY, T. ANNE

    FOR THIS RESEARCH, A TEST WAS SAID TO BE BIASED FOR MEMBERS OF A SUBGROUP OF THE POPULATION IF, IN THE PREDICTION OF A CRITERION FOR WHICH THE TEST WAS DESIGNED, CONSISTENT NONZERO ERRORS OF PREDICTION ARE MADE FOR MEMBERS OF THE SUBGROUP. SAMPLES OF NEGRO AND WHITE STUDENTS FROM THREE INTEGRATED COLLEGES WERE STUDIED. IN THE TWO EASTERN COLLEGES,…

  11. Researchers' Perceptions of Statistical Significance Contribute to Bias in Health and Exercise Science

    Science.gov (United States)

    Buchanan, Taylor L.; Lohse, Keith R.

    2016-01-01

    We surveyed researchers in the health and exercise sciences to explore different areas and magnitudes of bias in researchers' decision making. Participants were presented with scenarios (testing a central hypothesis with p = 0.06 or p = 0.04) in a random order and surveyed about what they would do in each scenario. Participants showed significant…

  12. Bias in Examination Test Banks that Accompany Cost Accounting Texts.

    Science.gov (United States)

    Clute, Ronald C.; McGrail, George R.

    1989-01-01

    Eight text banks that accompany cost accounting textbooks were evaluated for the presence of bias in the distribution of correct responses. All but one were found to have considerable bias, and three of eight were found to have significant choice bias. (SK)

  13. Flight research and testing

    Science.gov (United States)

    Putnam, Terrill W.; Ayers, Theodore G.

    1989-01-01

    Flight research and testing form a critical link in the aeronautic research and development chain. Brilliant concepts, elegant theories, and even sophisticated ground tests of flight vehicles are not sufficient to prove beyond a doubt that an unproven aeronautical concept will actually perform as predicted. Flight research and testing provide the ultimate proof that an idea or concept performs as expected. Ever since the Wright brothers, flight research and testing were the crucible in which aeronautical concepts were advanced and proven to the point that engineers and companies are willing to stake their future to produce and design aircraft. This is still true today, as shown by the development of the experimental X-30 aerospace plane. The Dryden Flight Research Center (Ames-Dryden) continues to be involved in a number of flight research programs that require understanding and characterization of the total airplane in all the aeronautical disciplines, for example the X-29. Other programs such as the F-14 variable-sweep transition flight experiment have focused on a single concept or discipline. Ames-Dryden also continues to conduct flight and ground based experiments to improve and expand the ability to test and evaluate advanced aeronautical concepts. A review of significant aeronautical flight research programs and experiments is presented to illustrate both the progress being made and the challenges to come.

  14. Is there a bias against telephone interviews in qualitative research?

    Science.gov (United States)

    Novick, Gina

    2008-08-01

    Telephone interviews are largely neglected in the qualitative research literature and, when discussed, they are often depicted as a less attractive alternative to face-to-face interviewing. The absence of visual cues via telephone is thought to result in loss of contextual and nonverbal data and to compromise rapport, probing, and interpretation of responses. Yet, telephones may allow respondents to feel relaxed and able to disclose sensitive information, and evidence is lacking that they produce lower quality data. This apparent bias against telephone interviews contrasts with a growing interest in electronic qualitative interviews. Research is needed comparing these modalities, and examining their impact on data quality and their use for studying varying topics and populations. Such studies could contribute evidence-based guidelines for optimizing interview data. 2008 Wiley Periodicals, Inc

  15. Testing Error Management Theory: Exploring the Commitment Skepticism Bias and the Sexual Overperception Bias

    Science.gov (United States)

    Henningsen, David Dryden; Henningsen, Mary Lynn Miller

    2010-01-01

    Research on error management theory indicates that men tend to overestimate women's sexual interest and women underestimate men's interest in committed relationships (Haselton & Buss, 2000). We test the assumptions of the theory in face-to-face, stranger interactions with 111 man-woman dyads. Support for the theory emerges, but potential boundary…

  16. Relation between education and dementia: the role of test bias revisited

    NARCIS (Netherlands)

    Schmand, B.; Lindeboom, J.; Hooijer, C.; Jonker, C.

    1995-01-01

    Several authors have suggested that dementia screening tests may be biased against low levels of education, whereas others find that a low level of education is a genuine risk factor for dementia. The present paper attempts to reconcile these conflicting views by examining item bias and test bias

  17. A test to identify judgement bias in mice

    NARCIS (Netherlands)

    Boleij, H.; van't Klooster, J.; Lavrijsen, M.; Kirchhoff, S.; Arndt, S.S.; Ohl, F.

    2012-01-01

    Emotional states are known to affect cognitive processes. For example highly anxious individuals interpret ambiguous stimuli more negatively than low anxious people, an effect called negative judgement bias. Recently, the measurement of judgement bias has been used to try and indicate emotional

  18. Common method biases in behavioral research: a critical review of the literature and recommended remedies.

    Science.gov (United States)

    Podsakoff, Philip M; MacKenzie, Scott B; Lee, Jeong-Yeon; Podsakoff, Nathan P

    2003-10-01

    Interest in the problem of method biases has a long history in the behavioral sciences. Despite this, a comprehensive summary of the potential sources of method biases and how to control for them does not exist. Therefore, the purpose of this article is to examine the extent to which method biases influence behavioral research results, identify potential sources of method biases, discuss the cognitive processes through which method biases influence responses to measures, evaluate the many different procedural and statistical techniques that can be used to control method biases, and provide recommendations for how to select appropriate procedural and statistical remedies for different types of research settings.

  19. Sex Bias in ASAT? ACER Research Monograph No. 24.

    Science.gov (United States)

    Adams, Raymond J.

    The Australian Scholastic Test (ASAT) was first used as a moderating device in the Australian Capitol Territory in 1977. Differences have been observed in the average performance of males and females on the test. The study reported in this monograph investigated the nature and origin of the score differences recorded for ASAT The research focused…

  20. Surprise, Memory, and Retrospective Judgment Making: Testing Cognitive Reconstruction Theories of the Hindsight Bias Effect

    Science.gov (United States)

    Ash, Ivan K.

    2009-01-01

    Hindsight bias has been shown to be a pervasive and potentially harmful decision-making bias. A review of 4 competing cognitive reconstruction theories of hindsight bias revealed conflicting predictions about the role and effect of expectation or surprise in retrospective judgment formation. Two experiments tested these predictions examining the…

  1. International gender bias in nursing research, 2005-2006: a quantitative content analysis.

    Science.gov (United States)

    Polit, Denise F; Beck, Cheryl Tatano

    2009-08-01

    This paper reports a study that examined the extent to which nurse researchers internationally disproportionately include females as participants in their research. A bias toward predominantly male samples has been well-documented in medical research, but recently a gender bias favoring women in nursing research has been identified in studies published in four North American journals. We extracted information about study samples and characteristics of the studies and authors from a consecutive sample of 834 studies published in eight leading English-language nursing research journals in 2005-2006. The primary analyses involved one-sample t-tests that tested the null hypothesis that males and females are equally represented as participants in nursing studies. Studies from different countries, in different specialty areas, and with varying author and methodologic characteristics were compared with regard to the key outcome variable, percent of participants who were female. Overall, 71% of participants, on average, were female, including 68% in client-focused research and 83% in nurse-focused studies (all presearch in almost all specialty areas, particularly in mental health, community health, health promotion, and geriatrics. The bias favoring female participants in client-focused studies was especially strong in the United States and Canada, but was also present in European countries, most Asian countries, and in Australia. Female overrepresentation was persistent, regardless of methodological characteristics (e.g., qualitative versus quantitative), funding source, and most researcher characteristics (e.g., academic rank). Studies with male authors, however, had more sex-balanced samples. The mean percentage female in client-focused studies with a female lead author was 70.0, compared to 52.1 for male lead authors. Nurse researchers not only in North America but around the globe need to pay attention to who will benefit from their research and to whether they are

  2. Investigator Bias and Theory-Ladenness in Cross-Cultural Research: Insights from Wittgenstein

    Science.gov (United States)

    Tan, Charlene

    2016-01-01

    A relatively under-explored topic in the current literature on and methods for research in the field of comparative and international education is the problem of investigator bias in cross-cultural research. This article discusses the nature of and an approach to address investigator bias in research that originates from the theory-ladenness of…

  3. A Test for Cluster Bias: Detecting Violations of Measurement Invariance across Clusters in Multilevel Data

    Science.gov (United States)

    Jak, Suzanne; Oort, Frans J.; Dolan, Conor V.

    2013-01-01

    We present a test for cluster bias, which can be used to detect violations of measurement invariance across clusters in 2-level data. We show how measurement invariance assumptions across clusters imply measurement invariance across levels in a 2-level factor model. Cluster bias is investigated by testing whether the within-level factor loadings…

  4. Sources of method bias in social science research and recommendations on how to control it.

    Science.gov (United States)

    Podsakoff, Philip M; MacKenzie, Scott B; Podsakoff, Nathan P

    2012-01-01

    Despite the concern that has been expressed about potential method biases, and the pervasiveness of research settings with the potential to produce them, there is disagreement about whether they really are a problem for researchers in the behavioral sciences. Therefore, the purpose of this review is to explore the current state of knowledge about method biases. First, we explore the meaning of the terms "method" and "method bias" and then we examine whether method biases influence all measures equally. Next, we review the evidence of the effects that method biases have on individual measures and on the covariation between different constructs. Following this, we evaluate the procedural and statistical remedies that have been used to control method biases and provide recommendations for minimizing method bias.

  5. Effects of sertraline, duloxetine, vortioxetine, and idazoxan in the rat affective bias test

    DEFF Research Database (Denmark)

    Refsgaard, Louise Konradsen; Haubro, Kia; Pickering, Darryl S

    2016-01-01

    Rationale Affective biases seemingly play a crucial role for the onset and development of depression. Acute treatment with monoamine-based antidepressants positively influence emotional processing, and an early correction of biases likely results in repeated positive experiences that ultimately...... lead to improved mood. Objectives Using two conventional antidepressants, sertraline and duloxetine, we aimed to forward the characterization of a newly developed affective bias test (ABT) for rats. Further, we examined the effect of vortioxetine, a recently approved antidepressant, and the α2...... adrenoceptor antagonist idazoxan on affective biases....

  6. Modification of cognitive biases related to posttraumatic stress: A systematic review and research agenda.

    Science.gov (United States)

    Woud, Marcella L; Verwoerd, Johan; Krans, Julie

    2017-06-01

    Cognitive models of Posttraumatic Stress Disorder (PTSD) postulate that cognitive biases in attention, interpretation, and memory represent key factors involved in the onset and maintenance of PTSD. Developments in experimental research demonstrate that it may be possible to manipulate such biases by means of Cognitive Bias Modification (CBM). In the present paper, we summarize studies assessing cognitive biases in posttraumatic stress to serve as a theoretical and methodological background. However, our main aim was to provide an overview of the scientific literature on CBM in (analogue) posttraumatic stress. Results of our systematic literature review showed that most CBM studies targeted attentional and interpretation biases (attention: five studies; interpretation: three studies), and one study modified memory biases. Overall, results showed that CBM can indeed modify cognitive biases and affect (analog) trauma symptoms in a training congruent manner. Interpretation bias procedures seemed effective in analog samples, and memory bias training proved preliminary success in a clinical PTSD sample. Studies of attention bias modification provided more mixed results. This heterogeneous picture may be explained by differences in the type of population or variations in the CBM procedure. Therefore, we sketched a detailed research agenda targeting the challenges for CBM in posttraumatic stress. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Cognitive bias in back pain patients attending osteopathy: testing the enmeshment model in reference to future thinking.

    Science.gov (United States)

    Read, Jessica; Pincus, Tamar

    2004-12-01

    Depressive symptoms are common in chronic pain. Previous research has found differences in information-processing biases in depressed pain patients and depressed people without pain. The schema enmeshment model of pain (SEMP) has been proposed to explain chronic pain patients' information-processing biases. Negative future thinking is common in depression but has not been explored in relation to chronic pain and information-processing models. The study aimed to test the SEMP with reference to future thinking. An information-processing paradigm compared endorsement and recall bias between depressed and non-depressed chronic low back pain patients and control participants. Twenty-five depressed and 35 non-depressed chronic low back pain patients and 25 control participants (student osteopaths) were recruited from an osteopathy practice. Participants were asked to endorse positive and negative ill-health, depression-related, and neutral (control) adjectives, encoded in reference to either current or future time-frame. Incidental recall of the adjectives was then tested. While the expected hypothesis of a recall bias by depressed pain patients towards ill-health stimuli in the current condition was confirmed, the recall bias was not present in the future condition. Additionally, patterns of endorsement and recall bias differed. Results extend understanding of future thinking in chronic pain within the context of the SEMP.

  8. Social desirability bias in personality testing: Implications for astronaut selection

    Science.gov (United States)

    Sandal, Gro M.; Musson, Dave; Helmreich, Robert. L.; Gravdal, Lene

    2005-07-01

    The assessment of personality is recognized by space agencies as an approach to identify candidates likely to perform optimally during spaceflights. In the use of personality scales for selection, the impact of social desirability (SD) has been cited as a concern. Study 1 addressed the impact of SD on responses to the Personality Characteristic Inventory (PCI) and NEO-FFI. This was achieved by contrasting scores from active astronauts (N=65) with scores of successful astronaut applicants (N=63), and between pilots applicants (N=1271) and pilot research subjects (N=120). Secondly, personality scores were correlated with scores on the Marlow Crown Social Desirability Scale among applicants to managerial positions (N=120). The results indicated that SD inflated scores on PCI scales assessing negative interpersonal characteristics, and impacted on four of five scales in NEO-FFI. Still, the effect sizes were small or moderate. Study 2 addressed performance implications of SD during an assessment of males applying to work as rescue personnel operations in the North Sea (N=22). The results showed that SD correlated negatively with cognitive test performance, and positively with discrepancy in performance ratings between self and two observers. In conclusion, caution is needed in interpreting personality scores in applicant populations. SD may be a negative predictor for performance under stress.

  9. Rater bias in psychological research: when is it a problem and what can we do about it?

    Science.gov (United States)

    Hoyt, W T

    2000-03-01

    Rater bias is a substantial source of error in psychological research. Bias distorts observed effect sizes beyond the expected level of attenuation due to intrarater error, and the impact of bias is not accurately estimated using conventional methods of correction for attenuation. Using a model based on multivariate generalizability theory, this article illustrates how bias affects research results. The model identifies 4 types of bias that may affect findings in research using observer ratings, including the biases traditionally termed leniency and halo errors. The impact of bias depends on which of 4 classes of rating design is used, and formulas are derived for correcting observed effect sizes for attenuation (due to bias variance) and inflation (due to bias covariance) in each of these classes. The rater bias model suggests procedures for researchers seeking to minimize adverse impact of bias on study findings.

  10. Data analysis strategies for reducing the influence of the bias in cross-cultural research.

    Science.gov (United States)

    Sindik, Josko

    2012-03-01

    In cross-cultural research, researchers have to adjust the constructs and associated measurement instruments that have been developed in one culture and then imported for use in another culture. Importing concepts from other cultures is often simply reduced to language adjustment of the content in the items of the measurement instruments that define a certain (psychological) construct. In the context of cross-cultural research, test bias can be defined as a generic term for all nuisance factors that threaten the validity of cross-cultural comparisons. Bias can be an indicator that instrument scores based on the same items measure different traits and characteristics across different cultural groups. To reduce construct, method and item bias,the researcher can consider these strategies: (1) simply comparing average results in certain measuring instruments; (2) comparing only the reliability of certain dimensions of the measurement instruments, applied to the "target" and "source" samples of participants, i.e. from different cultures; (3) comparing the "framed" factor structure (fixed number of factors) of the measurement instruments, applied to the samples from the "target" and "source" cultures, using explorative factor analysis strategy on separate samples; (4) comparing the complete constructs ("unframed" factor analysis, i.e. unlimited number of factors) in relation to their best psychometric properties and the possibility of interpreting (best suited to certain cultures, applying explorative strategy of factor analysis); or (5) checking the similarity of the constructs in the samples from different cultures (using structural equation modeling approach). Each approach has its advantages and disadvantages. The advantages and lacks of each approach are discussed.

  11. Recruitment bias in chronic pain research: whiplash as a model.

    Science.gov (United States)

    Nijs, Jo; Inghelbrecht, Els; Daenen, Liesbeth; Hachimi-Idrissi, Said; Hens, Luc; Willems, Bert; Roussel, Nathalie; Cras, Patrick; Wouters, Kristien; Bernheim, Jan

    2011-11-01

    In science findings which cannot be extrapolated to other settings are of little value. Recruitment methods vary widely across chronic whiplash studies, but it remains unclear whether this generates recruitment bias. The present study aimed to examine whether the recruitment method accounts for differences in health status, social support, and personality traits in patients with chronic whiplash-associated disorders (WAD). Two different recruitment methods were compared: recruiting patients through a local whiplash patient support group (group 1) and local hospital emergency department (group 2). The participants (n=118) filled in a set of questionnaires: the Neck Disability Index, Medical Outcome Study Short-Form General Health Survey, Anamnestic Comparative Self-Assessment measure of overall well-being, Symptom Checklist-90, Dutch Personality Questionnaire, and the Social Support List. The recruitment method (either through the local emergency department or patient support group) accounted for the differences in insufficiency, somatization, disability, quality of life, self-satisfaction, and dominance (all p values recruitment methods generated chronic WAD patients comparable for psychoneurotism, social support, self-sufficiency, (social) inadequacy, rigidity, and resentment (p>.01). The recruitment of chronic WAD patients solely through patient support groups generates bias with respect to the various aspects of health status and personality, but not social support. In order to enhance the external validity of study findings, chronic WAD studies should combine a variety of recruitment procedures.

  12. Empirical evidence of design-related bias in studies of diagnostic tests

    NARCIS (Netherlands)

    Lijmer, J. G.; Mol, B. W.; Heisterkamp, S.; Bonsel, G. J.; Prins, M. H.; van der Meulen, J. H.; Bossuyt, P. M.

    1999-01-01

    CONTEXT: The literature contains a large number of potential biases in the evaluation of diagnostic tests. Strict application of appropriate methodological criteria would invalidate the clinical application of most study results. OBJECTIVE: To empirically determine the quantitative effect of study

  13. Implicit Bias and Mental Health Professionals: Priorities and Directions for Research.

    Science.gov (United States)

    Merino, Yesenia; Adams, Leslie; Hall, William J

    2018-06-01

    This Open Forum explores the role of implicit bias along the mental health care continuum, which may contribute to mental health disparities among vulnerable populations. Emerging research shows that implicit bias is prevalent among service providers. These negative or stigmatizing attitudes toward population groups are held at a subconscious level and are automatically activated during practitioner-client encounters. The authors provide examples of how implicit bias may impede access to care, clinical screening and diagnosis, treatment processes, and crisis response. They also discuss how implicit attitudes may manifest at the intersection between mental health and criminal justice institutions. Finally, they discuss the need for more research on the impact of implicit bias on health practices throughout the mental health system, including the development of interventions to address implicit bias among mental health professionals.

  14. Mood As Cumulative Expectation Mismatch: A Test of Theory Based on Data from Non-verbal Cognitive Bias Tests

    Directory of Open Access Journals (Sweden)

    Camille M. C. Raoult

    2017-12-01

    Full Text Available Affective states are known to influence behavior and cognitive processes. To assess mood (moderately long-term affective states, the cognitive judgment bias test was developed and has been widely used in various animal species. However, little is known about how mood changes, how mood can be experimentally manipulated, and how mood then feeds back into cognitive judgment. A recent theory argues that mood reflects the cumulative impact of differences between obtained outcomes and expectations. Here expectations refer to an established context. Situations in which an established context fails to match an outcome are then perceived as mismatches of expectation and outcome. We take advantage of the large number of studies published on non-verbal cognitive bias tests in recent years (95 studies with a total of 162 independent tests to test whether cumulative mismatch could indeed have led to the observed mood changes. Based on a criteria list, we assessed whether mismatch had occurred with the experimental procedure used to induce mood (mood induction mismatch, or in the context of the non-verbal cognitive bias procedure (testing mismatch. For the mood induction mismatch, we scored the mismatch between the subjects’ potential expectations and the manipulations conducted for inducing mood whereas, for the testing mismatch, we scored mismatches that may have occurred during the actual testing. We then investigated whether these two types of mismatch can predict the actual outcome of the cognitive bias study. The present evaluation shows that mood induction mismatch cannot well predict the success of a cognitive bias test. On the other hand, testing mismatch can modulate or even inverse the expected outcome. We think, cognitive bias studies should more specifically aim at creating expectation mismatch while inducing mood states to test the cumulative mismatch theory more properly. Furthermore, testing mismatch should be avoided as much as possible

  15. Eye-movement evidence of the time-course of attentional bias for threatening pictures in test-anxious students.

    Science.gov (United States)

    Dong, Yunying; De Beuckelaer, Alain; Yu, Liang; Zhou, Renlai

    2017-06-01

    Protocols for measuring attentional bias to threat in test-anxiety, a special form of trait-anxiety, are rarely found in the literature. In our eye-tracking study, we introduced a new protocol, and studied the time-course of attention to test-related pictures with varying threat levels in 22 high test-anxious (HTA) and 22 low test-anxious (LTA) subjects. To determine whether attentional bias to test-related pictures is due to test-anxiety and not to state-anxiety, we also included a third group of 22 subjects with high state-anxiety but low test-anxiety (HSA). The subjects completed a free viewing task (FVT) in which high threat-neutral (HT-N) and low threat-neutral (LT-N) picture pairs were presented for 3 s. The results demonstrated that: (1) HTA subjects showed initial orienting to LT pictures, early attentional engagement with HT pictures later on and avoidance of HT pictures at the very end; (2) LTA subjects showed initial orienting to HT pictures and maintenance of attention on them later on; while (3) HSA subjects showed an initial orientation towards LT pictures and maintenance of attention on LT and HT pictures later on. These results suggest that, (high) test-anxiety is also prone to attentional bias towards test-related threat stimuli. Implications for future research are discussed.

  16. Anti-Atheist Bias in the United States: Testing Two Critical Assumptions

    Directory of Open Access Journals (Sweden)

    Lawton K Swan

    2012-02-01

    Full Text Available Decades of opinion polling and empirical investigations have clearly demonstrated a pervasive anti-atheist prejudice in the United States. However, much of this scholarship relies on two critical and largely unaddressed assumptions: (a that when people report negative attitudes toward atheists, they do so because they are reacting specifically to their lack of belief in God; and (b that survey questions asking about attitudes toward atheists as a group yield reliable information about biases against individual atheist targets. To test these assumptions, an online survey asked a probability-based random sample of American adults (N = 618 to evaluate a fellow research participant (“Jordan”. Jordan garnered significantly more negative evaluations when identified as an atheist than when described as religious or when religiosity was not mentioned. This effect did not differ as a function of labeling (“atheist” versus “no belief in God”, or the amount of individuating information provided about Jordan. These data suggest that both assumptions are tenable: nonbelief—rather than extraneous connotations of the word “atheist”—seems to underlie the effect, and participants exhibited a marked bias even when confronted with an otherwise attractive individual.

  17. Reducing Bias: Research Notes on Racism in America.

    Science.gov (United States)

    Mabbutt, Richard

    This paper highlights recent developments in research on racism in the United States, and notes several conceptual issues of significance for the long-range planning work of those interested in reducing racism in America and particularly in Idaho. Growth in the number of minority researchers has resulted in increased attention toward racism as it…

  18. Mobile Phone Cognitive Bias Modification Research Platform for Substance Use Disorders: Protocol for a Feasibility Study.

    Science.gov (United States)

    Zhang, Melvyn; Ying, JiangBo; Song, Guo; Fung, Daniel Ss; Smith, Helen

    2018-06-12

    Cognitive biases refer to automatic attentional and interpretational tendencies, which could be retained by cognitive bias modification interventions. Cristea et al and Jones et al have published reviews (in 2016 and 2017 respectively) on the effectiveness of such interventions. The advancement of technologies such as electronic health (eHealth) and mobile health (mHealth) has led to them being harnessed for the delivery of cognitive bias modification. To date, at least eight studies have demonstrated the feasibility of mobile technologies for the delivery of cognitive bias modification. Most of the studies are limited to a description of the conventional cognitive bias modification methodology that has been adopted. None of the studies shared the developmental process for the methodology involved, such that future studies could adopt it in the cost-effective replication of such interventions. It is important to have a common platform that could facilitate the design and customization of cognitive bias modification interventions for a variety of psychiatric and addictive disorders. It is the aim of the current research protocol to describe the design of a research platform that allows for customization of cognitive bias modification interventions for addictive disorders. A multidisciplinary team of 2 addiction psychiatrists, a psychologist with expertise in cognitive bias modification, and a computer engineer, were involved in the development of the intervention. The proposed platform would comprise of a mobile phone version of the cognitive bias task which is controlled by a server that could customize the algorithm for the tasks and collate the reaction-time data in realtime. The server would also allow the researcher to program the specific set of images that will be present in the task. The mobile phone app would synchronize with the backend server in real-time. An open-sourced cross-platform gaming software from React Native was used in the current development

  19. Bias associated with delayed verification in test accuracy studies: accuracy of tests for endometrial hyperplasia may be much higher than we think!

    OpenAIRE

    Clark, T Justin; ter Riet, Gerben; Coomarasamy, Aravinthan; Khan, Khalid S

    2004-01-01

    Abstract Background To empirically evaluate bias in estimation of accuracy associated with delay in verification of diagnosis among studies evaluating tests for predicting endometrial hyperplasia. Methods Systematic reviews of all published research on accuracy of miniature endometrial biopsy and endometr ial ultrasonography for diagnosing endometrial hyperplasia identified 27 test accuracy studies (2,982 subjects). Of these, 16 had immediate histological verification of diagnosis while 11 ha...

  20. Meta-research matters: Meta-spin cycles, the blindness of bias, and rebuilding trust.

    Science.gov (United States)

    Bero, Lisa

    2018-04-01

    Meta-research is research about research. Meta-research may not be as click-worthy as a meta-pug-a pug dog dressed up in a pug costume-but it is crucial to understanding research. A particularly valuable contribution of meta-research is to identify biases in a body of evidence. Bias can occur in the design, conduct, or publication of research and is a systematic deviation from the truth in results or inferences. The findings of meta-research can tell us which evidence to trust and what must be done to improve future research. We should be using meta-research to provide the evidence base for implementing systemic changes to improve research, not for discrediting it.

  1. Evaluating survey quality in health services research: a decision framework for assessing nonresponse bias.

    Science.gov (United States)

    Halbesleben, Jonathon R B; Whitman, Marilyn V

    2013-06-01

    To address the issue of nonresponse as problematic and offer appropriate strategies for assessing nonresponse bias. A review of current strategies used to assess the quality of survey data and the challenges associated with these strategies is provided along with appropriate post-data collection techniques that researchers should consider. Response rates are an incomplete assessment of survey data quality, and quick reactions to response rate should be avoided. Based on a five-question decision making framework, we offer potential ways to assess nonresponse bias, along with a description of the advantages and disadvantages to each. It is important that the quality of survey data be considered to assess the relative contribution to the literature of a given study. Authors and funding agencies should consider the potential effects of nonresponse bias both before and after survey administration and report the results of assessments of nonresponse bias in addition to response rates. © Health Research and Educational Trust.

  2. An Investigation of the Learning Strategies as Bias Factors in Second Language Cloze Tests

    Science.gov (United States)

    Ajideh, Parviz; Yaghoubi-Notash, Massoud; Khalili, Abdolreza

    2017-01-01

    The present study investigated the contribution of the EFL students' learning strategies to the explanation of the variance in their results on language tests. More specifically, it examined the role of these strategies as bias factors in the results of English cloze tests. Based on this aim, first, 158 intermediate EFL learners were selected from…

  3. Discursive biases of the environmental research framework DPSIR

    DEFF Research Database (Denmark)

    Svarstad, Hanne; Petersen, Lars Kjerulf; Rothman, Dale

    2008-01-01

    a critical examination of theoretical foundations of the DPSIR approach. We focus on the example of biodiversity, but our conclusions are relevant to other fields of environmental research. The DPSIR framework is viewed through the ‘lenses' of four major types of discourses on biodiversity: Preservationist......, Win-win, Traditionalist and Promethean. Based upon this examination, we argue that the DPSIR framework is not a tool generating neutral knowledge. Instead, application of this framework reproduces the discursive positions the applicant brings into it. We find that when applied in its traditional form...... to studies in the field of biodiversity, the framework is most compatible with the Preservationist discourse type and tends to favour conservationist and to neglect other positions. Thus, contrary to what is often claimed, we find that the DPSIR framework has shortcomings as a tool for establishing good...

  4. Can UK NHS research ethics committees effectively monitor publication and outcome reporting bias?

    Science.gov (United States)

    Begum, Rasheda; Kolstoe, Simon

    2015-07-25

    Publication and outcome reporting bias is often caused by researchers selectively choosing which scientific results and outcomes to publish. This behaviour is ethically significant as it distorts the literature used for future scientific or clinical decision-making. This study investigates the practicalities of using ethics applications submitted to a UK National Health Service (NHS) research ethics committee to monitor both types of reporting bias. As part of an internal audit we accessed research ethics database records for studies submitting an end of study declaration to the Hampshire A research ethics committee (formerly Southampton A) between 1st January 2010 and 31st December 2011. A literature search was used to establish the publication status of studies. Primary and secondary outcomes stated in application forms were compared with outcomes reported in publications. Out of 116 studies the literature search identified 57 publications for 37 studies giving a publication rate of 32%. Original Research Ethics Committee (REC) applications could be obtained for 28 of the published studies. Outcome inconsistencies were found in 16 (57%) of the published studies. This study showed that the problem of publication and outcome reporting bias is still significant in the UK. The method described here demonstrates that UK NHS research ethics committees are in a good position to detect such bias due to their unique access to original research protocols. Data gathered in this way could be used by the Health Research Authority to encourage higher levels of transparency in UK research.

  5. Research reactors and materials testing

    International Nuclear Information System (INIS)

    Vidal, H.

    1986-01-01

    Research reactors can be classified in three main groups according to the moderator which is used. Their technical characteristics are given and the three most recent research and materials testing reactors are described: OSIRIS, ORPHEE and the high-flux reactor of Grenoble. The utilization of research reactors is reviewed in four fields of activity: training, fundamental or applied research and production (eg. radioisotopes) [fr

  6. What we don't know can hurt us: Nonresponse bias assessment in birth defects research.

    Science.gov (United States)

    Strassle, Paula D; Cassell, Cynthia H; Shapira, Stuart K; Tinker, Sarah C; Meyer, Robert E; Grosse, Scott D

    2015-07-01

    Nonresponse bias assessment is an important and underutilized tool in survey research to assess potential bias due to incomplete participation. This study illustrates a nonresponse bias sensitivity assessment using a survey on perceived barriers to care for children with orofacial clefts in North Carolina. Children born in North Carolina between 2001 and 2004 with an orofacial cleft were eligible for inclusion. Vital statistics data, including maternal and child characteristics, were available on all eligible subjects. Missing 'responses' from nonparticipants were imputed using assumptions based on the distribution of responses, survey method (mail or phone), and participant maternal demographics. Overall, 245 of 475 subjects (51.6%) responded to either a mail or phone survey. Cost as a barrier to care was reported by 25.0% of participants. When stratified by survey type, 28.3% of mail respondents and 17.2% of phone respondents reported cost as a barrier. Under various assumptions, the bias-adjusted estimated prevalence of cost as barrier to care ranged from 16.1% to 30.0%. Maternal age, education, race, and marital status at time of birth were not associated with subjects reporting cost as a barrier. As survey response rates continue to decline, the importance of assessing the potential impact of nonresponse bias has become more critical. Birth defects research is particularly conducive to nonresponse bias analysis, especially when birth defect registries and birth certificate records are used. Future birth defect studies which use population-based surveillance data and have incomplete participation could benefit from this type of nonresponse bias assessment. Birth Defects Research (Part A) 103:603-609, 2015. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  7. Risk of Bias in Reports of In Vivo Research: A Focus for Improvement.

    Directory of Open Access Journals (Sweden)

    Malcolm R Macleod

    2015-10-01

    Full Text Available The reliability of experimental findings depends on the rigour of experimental design. Here we show limited reporting of measures to reduce the risk of bias in a random sample of life sciences publications, significantly lower reporting of randomisation in work published in journals of high impact, and very limited reporting of measures to reduce the risk of bias in publications from leading United Kingdom institutions. Ascertainment of differences between institutions might serve both as a measure of research quality and as a tool for institutional efforts to improve research quality.

  8. Explicit Bias Toward High-Income-Country Research: A Randomized, Blinded, Crossover Experiment Of English Clinicians.

    Science.gov (United States)

    Harris, Matthew; Marti, Joachim; Watt, Hillary; Bhatti, Yasser; Macinko, James; Darzi, Ara W

    2017-11-01

    Unconscious bias may interfere with the interpretation of research from some settings, particularly from lower-income countries. Most studies of this phenomenon have relied on indirect outcomes such as article citation counts and publication rates; few have addressed or proven the effect of unconscious bias in evidence interpretation. In this randomized, blinded crossover experiment in a sample of 347 English clinicians, we demonstrate that changing the source of a research abstract from a low- to a high-income country significantly improves how it is viewed, all else being equal. Using fixed-effects models, we measured differences in ratings for strength of evidence, relevance, and likelihood of referral to a peer. Having a high-income-country source had a significant overall impact on respondents' ratings of relevance and recommendation to a peer. Unconscious bias can have far-reaching implications for the diffusion of knowledge and innovations from low-income countries.

  9. Assessing bias against overweight individuals among nursing and psychology students: an implicit association test.

    Science.gov (United States)

    Waller, Tabitha; Lampman, Claudia; Lupfer-Johnson, Gwen

    2012-12-01

    To determine the implicit or unconscious attitudes of Nursing and Psychology majors towards overweight individuals in medical and non-medical contexts. Obesity is a leading health concern today, which impacts both physical and psychological health. Overweight individuals confront social biases in many aspects of their lives including health care. Examining the views of Nursing and Psychology students may reveal implicit attitudes towards overweight individuals that may lead to prejudiced behaviours. A mixed design experiment with one between-subjects variable (student major: Nursing or Psychology) and one within-subjects variable (condition: congruent or incongruent) was used to assess implicit attitudes in two convenience samples of Nursing and Psychology students. A computerised implicit association test was used to determine implicit attitudes towards overweight individuals in medical and non-medical contexts. A total of 90 students from Nursing (n= 45) and Psychology (n = 45) were recruited to complete an implicit association test. Reaction times in milliseconds between the congruent trials (stereotype consistent) and incongruent trials (stereotype inconsistent) were compared with determine adherence to social stereotypes or weight bias. A statistically significant implicit bias towards overweight individuals was detected in both subject groups and in both target settings (medical vs. non-medical). Stronger weight bias was found when the stimulus targets were female than male. Findings from this study expand understanding of the implicit attitudes and social biases of Nursing and Psychology students. The views held by these future healthcare professionals may negatively impact patient care. Providing education and support to overweight individuals is central to Nursing practice in a society struggling to manage obesity. Negative stereotypes or beliefs about these individuals may result in poor patient care. Therefore, nurses and other healthcare professionals

  10. The human fallibility of scientists : Dealing with error and bias in academic research

    NARCIS (Netherlands)

    Veldkamp, Coosje

    2017-01-01

    THE HUMAN FALLIBILITY OF SCIENTISTS Dealing with error and bias in academic research Recent studies have highlighted that not all published findings in the scientific lit¬erature are trustworthy, suggesting that currently implemented control mechanisms such as high standards for the reporting of

  11. Evidence-based medicine, the research-practice gap, and biases in medical and surgical decision making in dermatology.

    Science.gov (United States)

    Eaglstein, William H

    2010-10-01

    The objectives of this article are to promote a better understanding of a group of biases that influence therapeutic decision making by physicians/dermatologists and to raise the awareness that these biases contribute to a research-practice gap that has an impact on physicians and treatment solutions. The literature included a wide range of peer-reviewed articles dealing with biases in decision making, evidence-based medicine, randomized controlled clinical trials, and the research-practice gap. Bias against new therapies, bias in favor of indirect harm or omission, and bias against change when multiple new choices are offered may unconsciously affect therapeutic decision making. Although there is no comprehensive understanding or theory as to how choices are made by physicians, recognition of certain cognition patterns and their associated biases will help narrow the research-practice gap and optimize decision making regarding therapeutic choices.

  12. Publication bias in animal research presented at the 2008 Society of Critical Care Medicine Conference.

    Science.gov (United States)

    Conradi, Una; Joffe, Ari R

    2017-07-07

    To determine a direct measure of publication bias by determining subsequent full-paper publication (P) of studies reported in animal research abstracts presented at an international conference (A). We selected 100 random (using a random-number generator) A from the 2008 Society of Critical Care Medicine Conference. Using a data collection form and study manual, we recorded methodology and result variables from A. We searched PubMed and EMBASE to June 2015, and DOAJ and Google Scholar to May 2017 to screen for subsequent P. Methodology and result variables were recorded from P to determine changes in reporting from A. Predictors of P were examined using Fisher's Exact Test. 62% (95% CI 52-71%) of studies described in A were subsequently P after a median 19 [IQR 9-33.3] months from conference presentation. Reporting of studies in A was of low quality: randomized 27% (the method of randomization and allocation concealment not described), blinded 0%, sample-size calculation stated 0%, specifying the primary outcome 26%, numbers given with denominators 6%, and stating number of animals used 47%. Only being an orally presented (vs. poster presented) A (14/16 vs. 48/84, p = 0.025) predicted P. Reporting of studies in P was of poor quality: randomized 39% (the method of randomization and allocation concealment not described), likely blinded 6%, primary outcome specified 5%, sample size calculation stated 0%, numbers given with denominators 34%, and number of animals used stated 56%. Changes in reporting from A to P occurred: from non-randomized to randomized 19%, from non-blinded to blinded 6%, from negative to positive outcomes 8%, from having to not having a stated primary outcome 16%, and from non-statistically to statistically significant findings 37%. Post-hoc, using publication data, P was predicted by having positive outcomes (published 62/62, unpublished 33/38; p = 0.003), or statistically significant results (published 58/62, unpublished 20/38; p < 0

  13. 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

  14. The valuation of environmental goods in Norway: A contingent valuation study with multiple bias testing

    Energy Technology Data Exchange (ETDEWEB)

    Strand, J.; Taraldset, A.

    1991-01-01

    We report on a study of contingent valuation of reduction in air pollution, and of a broader set of six environmental issues, among a population sample in Oslo. We derive an estimate of the extent of upward bias due to mental accouting'' in the expressed valuation of the air pollution issue, in two steps: (1) by comparing valuation of air pollution alone, with the same when the other issues at the same time are to be dealt with; and (2) by deriving the implicit valuation of the air pollution issue from the ranking of issues, and total valuation of all six issues. We find that expressed valuation of air pollution reductions are 3-4 times as high as the true'' values, and argue that this discrepancy is mainly due to mental account biases. We also test for strategic, starting point, information and interviewer biases, which are all present and, with the exception of the information bias, all in the expected directions. 9 refs., 4 tabs.

  15. The valuation of environmental goods in Norway: A contingent valuation study with multiple bias testing

    Energy Technology Data Exchange (ETDEWEB)

    Strand, J.; Taraldset, A.

    1991-12-31

    We report on a study of contingent valuation of reduction in air pollution, and of a broader set of six environmental issues, among a population sample in Oslo. We derive an estimate of the extent of upward bias due to ``mental accouting`` in the expressed valuation of the air pollution issue, in two steps: (1) by comparing valuation of air pollution alone, with the same when the other issues at the same time are to be dealt with; and (2) by deriving the implicit valuation of the air pollution issue from the ranking of issues, and total valuation of all six issues. We find that expressed valuation of air pollution reductions are 3-4 times as high as the ``true`` values, and argue that this discrepancy is mainly due to mental account biases. We also test for strategic, starting point, information and interviewer biases, which are all present and, with the exception of the information bias, all in the expected directions. 9 refs., 4 tabs.

  16. Network Penetration Testing and Research

    Science.gov (United States)

    Murphy, Brandon F.

    2013-01-01

    This paper will focus the on research and testing done on penetrating a network for security purposes. This research will provide the IT security office new methods of attacks across and against a company's network as well as introduce them to new platforms and software that can be used to better assist with protecting against such attacks. Throughout this paper testing and research has been done on two different Linux based operating systems, for attacking and compromising a Windows based host computer. Backtrack 5 and BlackBuntu (Linux based penetration testing operating systems) are two different "attacker'' computers that will attempt to plant viruses and or NASA USRP - Internship Final Report exploits on a host Windows 7 operating system, as well as try to retrieve information from the host. On each Linux OS (Backtrack 5 and BlackBuntu) there is penetration testing software which provides the necessary tools to create exploits that can compromise a windows system as well as other operating systems. This paper will focus on two main methods of deploying exploits 1 onto a host computer in order to retrieve information from a compromised system. One method of deployment for an exploit that was tested is known as a "social engineering" exploit. This type of method requires interaction from unsuspecting user. With this user interaction, a deployed exploit may allow a malicious user to gain access to the unsuspecting user's computer as well as the network that such computer is connected to. Due to more advance security setting and antivirus protection and detection, this method is easily identified and defended against. The second method of exploit deployment is the method mainly focused upon within this paper. This method required extensive research on the best way to compromise a security enabled protected network. Once a network has been compromised, then any and all devices connected to such network has the potential to be compromised as well. With a compromised

  17. Strategies to Prevent or Reduce Gender Bias in Peer Review of Research Grants: A Rapid Scoping Review.

    Directory of Open Access Journals (Sweden)

    Andrea C Tricco

    Full Text Available To review the literature on strategies implemented or identified to prevent or reduce gender bias in peer review of research grants.Studies of any type of qualitative or quantitative design examining interventions to reduce or prevent gender bias during the peer review of health-related research grants were included. Electronic databases including MEDLINE, EMBASE, Education Resources Information Center (ERIC, PsycINFO, Joanna Briggs, the Cochrane Library, Evidence Based Medicine (EBM Reviews, and the Campbell Library were searched from 2005 to April 2016. A search for grey (i.e., difficult to locate or unpublished literature was conducted and experts in the field were consulted to identify additional potentially relevant articles. Two individuals screened titles and abstracts, full-text articles, and abstracted data with discrepancies resolved by a third person consistently.After screening 5524 citations and 170 full-text articles, one article evaluating gender-blinding of grant applications using an uncontrolled before-after study design was included. In this study, 891 applications for long-term fellowships in 2006 were included and 47% of the applicants were women. These were scored by 13 peer reviewers (38% were women. The intervention included eliminating references to gender from the applications, letters of recommendations, and interview reports that were sent to the committee members for evaluation. The proportion of successful applications led by women did not change with gender-blinding, although the number of successful applications that were led by men increased slightly.There is limited research on interventions to mitigate gender bias in the peer review of grants. Only one study was identified and no difference in the proportion of women who were successful in receiving grant funding was observed. Our results suggest that interventions to prevent gender bias should be adapted and tested in the context of grant peer review to

  18. Preliminary Validation of a New Measure of Negative Response Bias: The Temporal Memory Sequence Test.

    Science.gov (United States)

    Hegedish, Omer; Kivilis, Naama; Hoofien, Dan

    2015-01-01

    The Temporal Memory Sequence Test (TMST) is a new measure of negative response bias (NRB) that was developed to enrich the forced-choice paradigm. The TMST does not resemble the common structure of forced-choice tests and is presented as a temporal recall memory test. The validation sample consisted of 81 participants: 21 healthy control participants, 20 coached simulators, and 40 patients with acquired brain injury (ABI). The TMST had high reliability and significantly high positive correlations with the Test of Memory Malingering and Word Memory Test effort scales. Moreover, the TMST effort scales exhibited high negative correlations with the Glasgow Coma Scale, thus validating the previously reported association between probable malingering and mild traumatic brain injury. A suggested cutoff score yielded acceptable classification rates in the ABI group as well as in the simulator and control groups. The TMST appears to be a promising measure of NRB detection, with respectable rates of reliability and construct and criterion validity.

  19. Investigation of publication bias in meta-analyses of diagnostic test accuracy: a meta-epidemiological study

    NARCIS (Netherlands)

    van Enst, W. Annefloor; Ochodo, Eleanor; Scholten, Rob J. P. M.; Hooft, Lotty; Leeflang, Mariska M.

    2014-01-01

    The validity of a meta-analysis can be understood better in light of the possible impact of publication bias. The majority of the methods to investigate publication bias in terms of small study-effects are developed for meta-analyses of intervention studies, leaving authors of diagnostic test

  20. Completeness and Bias Tests of Small Flares in gPhoton M Dwarfs

    Science.gov (United States)

    Fleming, Scott W.; Million, Chase; Brasseur, Clara; Osten, Rachel A.; Shiao, Bernie; Bianchi, Luciana

    2018-01-01

    gPhoton is a time-tagged database of more than one trillion calibrated ultraviolet photon events from the ten-year GALEX mission. With the open-source gPhoton software, users can construct images and light curves at user-defined temporal and spatial scales. We have been working on a project to detect stellar flares on M dwarfs observed in GALEX data, with particular focus on smaller flares that have durations between 30 seconds and 30 minutes, and energies between 10^27 and 10^29 ergs. This parameter space is still largely unconstrained in the UV/optical, even with Kepler/K2 data, due to their short durations. We present completeness and reliability tests we are conducting to be able to account for selection and detection bias in our sample, including stellar type, instrument artifacts, sampling bias, and signal-to-noise. The bias-corrected occurrence rate of such flares, which are exponentially more frequent than larger flares already characterized by Kepler and ground-based studies, can be included in future calculations of exoplanet habitability.

  1. Dissemination bias in systematic reviews of animal research: a systematic review.

    Directory of Open Access Journals (Sweden)

    Katharina F Mueller

    Full Text Available Systematic reviews of preclinical studies, in vivo animal experiments in particular, can influence clinical research and thus even clinical care. Dissemination bias, selective dissemination of positive or significant results, is one of the major threats to validity in systematic reviews also in the realm of animal studies. We conducted a systematic review to determine the number of published systematic reviews of animal studies until present, to investigate their methodological features especially with respect to assessment of dissemination bias, and to investigate the citation of preclinical systematic reviews on clinical research.Eligible studies for this systematic review constitute systematic reviews that summarize in vivo animal experiments whose results could be interpreted as applicable to clinical care. We systematically searched Ovid Medline, Embase, ToxNet, and ScienceDirect from 1st January 2009 to 9th January 2013 for eligible systematic reviews without language restrictions. Furthermore we included articles from two previous systematic reviews by Peters et al. and Korevaar et al.The literature search and screening process resulted in 512 included full text articles. We found an increasing number of published preclinical systematic reviews over time. The methodological quality of preclinical systematic reviews was low. The majority of preclinical systematic reviews did not assess methodological quality of the included studies (71%, nor did they assess heterogeneity (81% or dissemination bias (87%. Statistics quantifying the importance of clinical research citing systematic reviews of animal studies showed that clinical studies referred to the preclinical research mainly to justify their study or a future study (76%.Preclinical systematic reviews may have an influence on clinical research but their methodological quality frequently remains low. Therefore, systematic reviews of animal research should be critically appraised before

  2. Taxonomic and Geographic Bias in Conservation Biology Research: A Systematic Review of Wildfowl Demography Studies.

    Science.gov (United States)

    Roberts, Beth E I; Harris, W Edwin; Hilton, Geoff M; Marsden, Stuart J

    2016-01-01

    Demographic data are important to wildlife managers to gauge population health, to allow populations to be utilised sustainably, and to inform conservation efforts. We analysed published demographic data on the world's wildfowl to examine taxonomic and geographic biases in study, and to identify gaps in knowledge. Wildfowl (order: Anseriformes) are a comparatively well studied bird group which includes 169 species of duck, goose and swan. In all, 1,586 wildfowl research papers published between 1911 and 2010 were found using Web of Knowledge (WoK) and Google Scholar. Over half of the research output involved just 15 species from seven genera. Research output was strongly biased towards 'high income' countries, common wildfowl species, and measures of productivity, rather than survival and movement patterns. There were significantly fewer demographic data for the world's 31 threatened wildfowl species than for non-threatened species. Since 1994, the volume of demographic work on threatened species has increased more than for non-threatened species, but still makes up only 2.7% of total research output. As an aid to research prioritisation, a metric was created to reflect demographic knowledge gaps for each species related to research output for the species, its threat status, and availability of potentially useful surrogate data from congeneric species. According to the metric, the 25 highest priority species include thirteen threatened taxa and nine species each from Asia and South America, and six from Africa.

  3. 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

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

    Directory of Open Access Journals (Sweden)

    Ingrid Toews

    Full Text Available 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

  5. 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

  6. Thermal Cycling and High Temperature Reverse Bias Testing of Control and Irradiated Gallium Nitride Power Transistors

    Science.gov (United States)

    Patterson, Richard L.; Boomer, Kristen T.; Scheick, Leif; Lauenstein, Jean-Marie; Casey, Megan; Hammoud, Ahmad

    2014-01-01

    The power systems for use in NASA space missions must work reliably under harsh conditions including radiation, thermal cycling, and exposure to extreme temperatures. Gallium nitride semiconductors show great promise, but information pertaining to their performance is scarce. Gallium nitride N-channel enhancement-mode field effect transistors made by EPC Corporation in a 2nd generation of manufacturing were exposed to radiation followed by long-term thermal cycling and testing under high temperature reverse bias conditions in order to address their reliability for use in space missions. Result of the experimental work are presented and discussed.

  7. Opinions and potential solutions regarding dissemination bias from funding agencies of biomedical research in Europe.

    Science.gov (United States)

    Pardo-Hernandez, Hector; Urrútia, Gerard; Meerpohl, Joerg J; Marušić, Ana; Wager, Elizabeth; Bonfill, Xavier

    2018-02-01

    Several studies have found that about half of research results from clinical trials are never published. Until now, there has been little information on the views that funding agencies of biomedical research in Europe have regarding this issue and its possible solutions. An electronic survey was conducted among funding agencies from 34 European countries. Participants were asked about their opinions, policies, and potential solutions regarding dissemination bias. On the basis of the results of this survey and the input of the OPEN Consortium and of representatives of stakeholder groups in the knowledge generation process, we formulated recommendations for funding agencies to reduce dissemination bias. We received responses from 64 funding agencies of biomedical medicine from most European countries, out of 245 that were contacted (26%). Of these, 56 funded research at the national and/or international level and were therefore eligible to participate. Policies encouraging publication increased over time: 33 (58.9%) of agencies enforced them in 2005 compared to 38 (67.6%) in 2012. However, only 13 (23.2%) had knowledge of the publications related to research funded in 2005, 23 (41.1%) were able to provide only an estimate, and 20 (35.7%) did not know at all. Regarding recommendations to control dissemination bias, we propose that funding agencies request the dissemination of research results irrespective of the direction of findings. We also call for measures that allow evaluating funded projects past the contractual period and until dissemination of results. Funding agencies should create publicly accessible databases with information on funded projects and dissemination efforts. Despite having policies to encourage publication of results, most funding agencies fail to implement such measures or to ensure compliance. We propose recommendations that could be incorporated in the blueprint of calls for proposals and contracts agreed upon by funding agencies and grant

  8. Effectiveness of the Comalli Stroop Test as a measure of negative response bias.

    Science.gov (United States)

    Arentsen, Timothy J; Boone, Kyle Brauer; Lo, Tracy T Y; Goldberg, Hope E; Cottingham, Maria E; Victor, Tara L; Ziegler, Elizabeth; Zeller, Michelle A

    2013-01-01

    Practice guidelines recommend the use of multiple performance validity tests (PVTs) to detect noncredible performance during neuropsychological evaluations, and PVTs embedded in standard cognitive tests achieve this goal most efficiently. The present study examined the utility of the Comalli version of the Stroop Test as a measure of response bias in a large sample of "real world" noncredible patients (n = 129) as compared with credible neuropsychology clinic patients (n=233). The credible group performed significantly better than the noncredible group on all trials, but particularly on word-reading (Stroop A) and color-naming (Stroop B); cut-scores for Stroop A and Stroop B trials were associated with moderate sensitivity (49-53%) as compared to the low sensitivity found for the color interference trial (29%). Some types of diagnoses (including learning disability, severe traumatic brain injury, psychosis, and depression), very advanced age (⩾80), and lowered IQ were associated with increased rates of false positive identifications, suggesting the need for some adjustments to cut-offs in these subgroups. Despite some previous reports of an inverted Stroop effect (i.e., color-naming worse than color interference) in noncredible subjects, individual Stroop word reading and color naming trials were much more effective in identifying response bias.

  9. Scientific research on animal biodiversity is systematically biased towards vertebrates and temperate regions.

    Directory of Open Access Journals (Sweden)

    Mark A Titley

    Full Text Available Over the last 25 years, research on biodiversity has expanded dramatically, fuelled by increasing threats to the natural world. However, the number of published studies is heavily weighted towards certain taxa, perhaps influencing conservation awareness of and funding for less-popular groups. Few studies have systematically quantified these biases, although information on this topic is important for informing future research and conservation priorities. We investigated: i which animal taxa are being studied; ii if any taxonomic biases are the same in temperate and tropical regions; iii whether the taxon studied is named in the title of papers on biodiversity, perhaps reflecting a perception of what biodiversity is; iv the geographical distribution of biodiversity research, compared with the distribution of biodiversity and threatened species; and v the geographical distribution of authors' countries of origin. To do this, we used the search engine Web of Science to systematically sample a subset of the published literature with 'biodiversity' in the title. In total 526 research papers were screened-5% of all papers in Web of Science with biodiversity in the title. For each paper, details on taxonomic group, title phrasing, number of citations, study location, and author locations were recorded. Compared to the proportions of described species, we identified a considerable taxonomic weighting towards vertebrates and an under-representation of invertebrates (particularly arachnids and insects in the published literature. This discrepancy is more pronounced in highly cited papers, and in tropical regions, with only 43% of biodiversity research in the tropics including invertebrates. Furthermore, while papers on vertebrate taxa typically did not specify the taxonomic group in the title, the converse was true for invertebrate papers. Biodiversity research is also biased geographically: studies are more frequently carried out in developed countries

  10. Ensuring transparency and minimization of methodologic bias in preclinical pain research: PPRECISE considerations.

    Science.gov (United States)

    Andrews, Nick A; Latrémolière, Alban; Basbaum, Allan I; Mogil, Jeffrey S; Porreca, Frank; Rice, Andrew S C; Woolf, Clifford J; Currie, Gillian L; Dworkin, Robert H; Eisenach, James C; Evans, Scott; Gewandter, Jennifer S; Gover, Tony D; Handwerker, Hermann; Huang, Wenlong; Iyengar, Smriti; Jensen, Mark P; Kennedy, Jeffrey D; Lee, Nancy; Levine, Jon; Lidster, Katie; Machin, Ian; McDermott, Michael P; McMahon, Stephen B; Price, Theodore J; Ross, Sarah E; Scherrer, Grégory; Seal, Rebecca P; Sena, Emily S; Silva, Elizabeth; Stone, Laura; Svensson, Camilla I; Turk, Dennis C; Whiteside, Garth

    2016-04-01

    There is growing concern about lack of scientific rigor and transparent reporting across many preclinical fields of biological research. Poor experimental design and lack of transparent reporting can result in conscious or unconscious experimental bias, producing results that are not replicable. The Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION) public-private partnership with the U.S. Food and Drug Administration sponsored a consensus meeting of the Preclinical Pain Research Consortium for Investigating Safety and Efficacy (PPRECISE) Working Group. International participants from universities, funding agencies, government agencies, industry, and a patient advocacy organization attended. Reduction of publication bias, increasing the ability of others to faithfully repeat experimental methods, and increased transparency of data reporting were specifically discussed. Parameters deemed essential to increase confidence in the published literature were clear, specific reporting of an a priori hypothesis and definition of primary outcome measure. Power calculations and whether measurement of minimal meaningful effect size to determine these should be a core component of the preclinical research effort provoked considerable discussion, with many but not all agreeing. Greater transparency of reporting should be driven by scientists, journal editors, reviewers, and grant funders. The conduct of high-quality science that is fully reported should not preclude novelty and innovation in preclinical pain research, and indeed, any efforts that curtail such innovation would be misguided. We believe that to achieve the goal of finding effective new treatments for patients with pain, the pain field needs to deal with these challenging issues.

  11. Patterns and biases in climate change research on amphibians and reptiles: a systematic review.

    Science.gov (United States)

    Winter, Maiken; Fiedler, Wolfgang; Hochachka, Wesley M; Koehncke, Arnulf; Meiri, Shai; De la Riva, Ignacio

    2016-09-01

    Climate change probably has severe impacts on animal populations, but demonstrating a causal link can be difficult because of potential influences by additional factors. Assessing global impacts of climate change effects may also be hampered by narrow taxonomic and geographical research foci. We review studies on the effects of climate change on populations of amphibians and reptiles to assess climate change effects and potential biases associated with the body of work that has been conducted within the last decade. We use data from 104 studies regarding the effect of climate on 313 species, from 464 species-study combinations. Climate change effects were reported in 65% of studies. Climate change was identified as causing population declines or range restrictions in half of the cases. The probability of identifying an effect of climate change varied among regions, taxa and research methods. Climatic effects were equally prevalent in studies exclusively investigating climate factors (more than 50% of studies) and in studies including additional factors, thus bolstering confidence in the results of studies exclusively examining effects of climate change. Our analyses reveal biases with respect to geography, taxonomy and research question, making global conclusions impossible. Additional research should focus on under-represented regions, taxa and questions. Conservation and climate policy should consider the documented harm climate change causes reptiles and amphibians.

  12. Hope for the best or prepare for the worst? Towards a spatial cognitive bias test for mice.

    Directory of Open Access Journals (Sweden)

    Vanessa Kloke

    Full Text Available Cognitive bias, the altered information processing resulting from the background emotional state of an individual, has been suggested as a promising new indicator of animal emotion. Comparable to anxious or depressed humans, animals in a putatively negative emotional state are more likely to judge an ambiguous stimulus as if it predicts a negative event, than those in positive states. The present study aimed to establish a cognitive bias test for mice based on a spatial judgment task and to apply it in a pilot study to serotonin transporter (5-HTT knockout mice, a well-established mouse model for the study of anxiety- and depression-related behavior. In a first step, we validated that our setup can assess different expectations about the outcome of an ambiguous stimulus: mice having learned to expect something positive within a maze differed significantly in their behavior towards an unfamiliar location than animals having learned to expect something negative. In a second step, the use of spatial location as a discriminatory stimulus was confirmed by showing that mice interpret an ambiguous stimulus depending on its spatial location, with a position exactly midway between a positive and a negative reference point provoking the highest level of ambiguity. Finally, the anxiety- and depression-like phenotype of the 5-HTT knockout mouse model manifested--comparable to human conditions--in a trend for a negatively distorted interpretation of ambiguous information, albeit this effect was not statistically significant. The results suggest that the present cognitive bias test provides a useful basis to study the emotional state in mice, which may not only increase the translational value of animal models in the study of human affective disorders, but which is also a central objective of animal welfare research.

  13. Hope for the best or prepare for the worst? Towards a spatial cognitive bias test for mice.

    Science.gov (United States)

    Kloke, Vanessa; Schreiber, Rebecca S; Bodden, Carina; Möllers, Julian; Ruhmann, Hanna; Kaiser, Sylvia; Lesch, Klaus-Peter; Sachser, Norbert; Lewejohann, Lars

    2014-01-01

    Cognitive bias, the altered information processing resulting from the background emotional state of an individual, has been suggested as a promising new indicator of animal emotion. Comparable to anxious or depressed humans, animals in a putatively negative emotional state are more likely to judge an ambiguous stimulus as if it predicts a negative event, than those in positive states. The present study aimed to establish a cognitive bias test for mice based on a spatial judgment task and to apply it in a pilot study to serotonin transporter (5-HTT) knockout mice, a well-established mouse model for the study of anxiety- and depression-related behavior. In a first step, we validated that our setup can assess different expectations about the outcome of an ambiguous stimulus: mice having learned to expect something positive within a maze differed significantly in their behavior towards an unfamiliar location than animals having learned to expect something negative. In a second step, the use of spatial location as a discriminatory stimulus was confirmed by showing that mice interpret an ambiguous stimulus depending on its spatial location, with a position exactly midway between a positive and a negative reference point provoking the highest level of ambiguity. Finally, the anxiety- and depression-like phenotype of the 5-HTT knockout mouse model manifested--comparable to human conditions--in a trend for a negatively distorted interpretation of ambiguous information, albeit this effect was not statistically significant. The results suggest that the present cognitive bias test provides a useful basis to study the emotional state in mice, which may not only increase the translational value of animal models in the study of human affective disorders, but which is also a central objective of animal welfare research.

  14. Cognitive Biases in Children and Adolescents With Chronic Pain: A Review of Findings and a Call for Developmental Research.

    Science.gov (United States)

    Lau, Jennifer Y F; Heathcote, Lauren C; Beale, Sarah; Gray, Suzy; Jacobs, Konrad; Wilkinson, Nick; Crombez, Geert

    2018-06-01

    Cognitive biases that emphasize bodily harm, injury, and illness could play a role in the maintenance of chronic pain by facilitating fear and avoidance. Whereas extensive research has established attention, interpretation, and memory biases in adults with chronic pain, far less is known about these same biases in children and adolescents with pain. Studying cognitive biases in attention, interpretation, and memory in relation to pain occurring in youth is important because youth is a time when pain can first become chronic, and when relationships between cognitive biases and pain outcomes emerge and stabilize. Thus, youth potentially offers a time window for the prevention of chronic pain problems. In this article, we summarize the growing corpus of data that have measured cognitive biases in relation to pediatric pain. We conclude that although biases in attention, interpretation, and memory characterize children and adolescents with varying pain experiences, questions regarding the direction, magnitude, nature, and role of these biases remain. We call for independent extension of cognitive bias research in children and adolescents, using well powered longitudinal studies with wide age ranges and psychometrically sound experimental measures to clarify these findings and any developmental trends in the links between cognitive biases and pain outcomes. This article provides a rationale for the theoretical and practical importance of studying the role of cognitive biases in children and adolescents with chronic pain, which has to date, been relatively understudied. Existing findings are reviewed critically, and recommendations for future research are offered. Copyright © 2018 The American Pain Society. Published by Elsevier Inc. All rights reserved.

  15. Conceptual fluency at test shifts recognition response bias in Alzheimer's disease: implications for increased false recognition.

    Science.gov (United States)

    Gold, Carl A; Marchant, Natalie L; Koutstaal, Wilma; Schacter, Daniel L; Budson, Andrew E

    2007-09-20

    The presence or absence of conceptual information in pictorial stimuli may explain the mixed findings of previous studies of false recognition in patients with mild Alzheimer's disease (AD). To test this hypothesis, 48 patients with AD were compared to 48 healthy older adults on a recognition task first described by Koutstaal et al. [Koutstaal, W., Reddy, C., Jackson, E. M., Prince, S., Cendan, D. L., & Schacter D. L. (2003). False recognition of abstract versus common objects in older and younger adults: Testing the semantic categorization account. Journal of Experimental Psychology: Learning, Memory, and Cognition, 29, 499-510]. Participants studied and were tested on their memory for categorized ambiguous pictures of common objects. The presence of conceptual information at study and/or test was manipulated by providing or withholding disambiguating semantic labels. Analyses focused on testing two competing theories. The semantic encoding hypothesis, which posits that the inter-item perceptual details are not encoded by AD patients when conceptual information is present in the stimuli, was not supported by the findings. In contrast, the conceptual fluency hypothesis was supported. Enhanced conceptual fluency at test dramatically shifted AD patients to a more liberal response bias, raising their false recognition. These results suggest that patients with AD rely on the fluency of test items in making recognition memory decisions. We speculate that AD patients' over reliance upon fluency may be attributable to (1) dysfunction of the hippocampus, disrupting recollection, and/or (2) dysfunction of prefrontal cortex, disrupting post-retrieval processes.

  16. Frontal brain deactivation during a non-verbal cognitive judgement bias test in sheep.

    Science.gov (United States)

    Guldimann, Kathrin; Vögeli, Sabine; Wolf, Martin; Wechsler, Beat; Gygax, Lorenz

    2015-02-01

    Animal welfare concerns have raised an interest in animal affective states. These states also play an important role in the proximate control of behaviour. Due to their potential to modulate short-term emotional reactions, one specific focus is on long-term affective states, that is, mood. These states can be assessed by using non-verbal cognitive judgement bias paradigms. Here, we conducted a spatial variant of such a test on 24 focal animals that were kept under either unpredictable, stimulus-poor or predictable, stimulus-rich housing conditions to induce differential mood states. Based on functional near-infrared spectroscopy, we measured haemodynamic frontal brain reactions during 10 s in which the sheep could observe the configuration of the cognitive judgement bias trial before indicating their assessment based on the go/no-go reaction. We used (generalised) mixed-effects models to evaluate the data. Sheep from the unpredictable, stimulus-poor housing conditions took longer and were less likely to reach the learning criterion and reacted slightly more optimistically in the cognitive judgement bias test than sheep from the predictable, stimulus-rich housing conditions. A frontal cortical increase in deoxy-haemoglobin [HHb] and a decrease in oxy-haemoglobin [O2Hb] were observed during the visual assessment of the test situation by the sheep, indicating a frontal cortical brain deactivation. This deactivation was more pronounced with the negativity of the test situation, which was reflected by the provenance of the sheep from the unpredictable, stimulus-poor housing conditions, the proximity of the cue to the negatively reinforced cue location, or the absence of a go reaction in the trial. It seems that (1) sheep from the unpredictable, stimulus-poor in comparison to sheep from the predictable, stimulus-rich housing conditions dealt less easily with the test conditions rich in stimuli, that (2) long-term housing conditions seemingly did not influence mood

  17. Testing for Bias against Female Test Takers of the Graduate Management Admissions Test and Potential Impact on Admissions to Graduate Programs in Business.

    Science.gov (United States)

    Wright, Robert E.; Bachrach, Daniel G.

    2003-01-01

    Graduate Management Admission Test (GMAT) scores and grade point average in graduate core courses were compared for 190 male and 144 female business administration students. No significant differences in course performance were found, but males had been admitted with significantly higher GMAT scores, suggesting a bias against women. (Contains 27…

  18. Illustrating, Quantifying, and Correcting for Bias in Post-hoc Analysis of Gene-Based Rare Variant Tests of Association

    Science.gov (United States)

    Grinde, Kelsey E.; Arbet, Jaron; Green, Alden; O'Connell, Michael; Valcarcel, Alessandra; Westra, Jason; Tintle, Nathan

    2017-01-01

    To date, gene-based rare variant testing approaches have focused on aggregating information across sets of variants to maximize statistical power in identifying genes showing significant association with diseases. Beyond identifying genes that are associated with diseases, the identification of causal variant(s) in those genes and estimation of their effect is crucial for planning replication studies and characterizing the genetic architecture of the locus. However, we illustrate that straightforward single-marker association statistics can suffer from substantial bias introduced by conditioning on gene-based test significance, due to the phenomenon often referred to as “winner's curse.” We illustrate the ramifications of this bias on variant effect size estimation and variant prioritization/ranking approaches, outline parameters of genetic architecture that affect this bias, and propose a bootstrap resampling method to correct for this bias. We find that our correction method significantly reduces the bias due to winner's curse (average two-fold decrease in bias, p bias and improve inference in post-hoc analysis of gene-based tests under a wide variety of genetic architectures. PMID:28959274

  19. Educational Research with Real-World Data: Reducing Selection Bias with Propensity Scores

    Directory of Open Access Journals (Sweden)

    Jill L. Adelson

    2013-12-01

    Full Text Available Often it is infeasible or unethical to use random assignment in educational settings to study important constructs and questions. Hence, educational research often uses observational data, such as large-scale secondary data sets and state and school district data, and quasi-experimental designs. One method of reducing selection bias in estimations of treatment effects is propensity score analysis. This method reduces a large number of pretreatment covariates to a single scalar function and allows researchers to compare subjects with similar probability to receive the treatment. This article provides an introduction to propensity score analysis and stratification, an example illustrating its use, and suggestions for using propensity score analysis in educational research.

  20. Optimal Testing Environment. Research Brief

    Science.gov (United States)

    Walker, Karen

    2010-01-01

    Even though it often feels like standardized testing is a relatively recent phenomena, it has been around at least since the 1800s, when in China, those that wanted a government job were required to take a test on their expertise of Confucian philosophy and poetry. During the Industrial Revolution, standardized tests were a quick way to test large…

  1. Considerations about expected a posteriori estimation in adaptive testing: adaptive a priori, adaptive correction for bias, and adaptive integration interval.

    Science.gov (United States)

    Raiche, Gilles; Blais, Jean-Guy

    2009-01-01

    In a computerized adaptive test, we would like to obtain an acceptable precision of the proficiency level estimate using an optimal number of items. Unfortunately, decreasing the number of items is accompanied by a certain degree of bias when the true proficiency level differs significantly from the a priori estimate. The authors suggest that it is possible to reduced the bias, and even the standard error of the estimate, by applying to each provisional estimation one or a combination of the following strategies: adaptive correction for bias proposed by Bock and Mislevy (1982), adaptive a priori estimate, and adaptive integration interval.

  2. Anxiety-linked attentional bias and its modification: Illustrating the importance of distinguishing processes and procedures in experimental psychopathology research.

    Science.gov (United States)

    MacLeod, Colin; Grafton, Ben

    2016-11-01

    In this review of research concerning anxiety-linked attentional bias, we seek to illustrate a general principle that we contend applies across the breadth of experimental psychopathology. Specifically, we highlight how maintenance of a clear distinction between process and procedure serves to enhance the advancement of knowledge and understanding, while failure to maintain this distinction can foster confusion and misconception. We show how such clear differentiation has permitted the continuous refinement of assessment procedures, in ways that have led to growing confidence in the existence of the putative attentional bias process of interest, and also increasing understanding of its nature. In contrast, we show how a failure to consistently differentiate between process and procedure has contributed to confusion concerning whether or not attentional bias modification reliably alters anxiety vulnerability and dysfunction. As we demonstrate, such confusion can be avoided by distinguishing the process of attentional bias modification from the procedures that have been employed with the intention of evoking this target process. Such an approach reveals that procedures adopted with the intention of eliciting the attentional bias modification process do not always do so, but that successful evocation of the attentional bias modification process quite reliably alters anxiety symptomatology. We consider some of the specific implications for future research concerning attentional bias modification, while also pointing to the broader implications for experimental psychopathology research in general. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Untold stories: biases and selection effects in research with victims of trafficking for sexual exploitation.

    Science.gov (United States)

    Brunovskis, Anette; Surtees, Rebecca

    2010-01-01

    Recent discussions of trafficking research have included calls for more innovative studies and new methodologies in order to move beyond the current trafficking narrative, which is often based on unrepresentative samples and overly simplified images. While new methods can potentially play a role in expanding the knowledge base on trafficking, this article argues that the solution is not entirely about applying new methods, but as much about using current methods to greater effect and with careful attention to their limitations and ethical constraints. Drawing on the authors' experience in researching trafficking issues in a number of projects over the past decade, the article outlines and exemplifies some of the methodological and ethical issues to be considered and accommodated when conducting research with trafficked persons -- including unrepresentative samples; access to respondents; selection biases by "gatekeepers" and self selection by potential respondents. Such considerations should inform not only how research is undertaken but also how this information is read and understood. Moreover, many of these considerations equally apply when considering the application of new methods within this field. The article maintains that a better understanding of how these issues come into play and inform trafficking research will translate into tools for conducting improved research in this field and, by implication, new perspectives on human trafficking.

  4. Evaluating the impact of method bias in health behaviour research: a meta-analytic examination of studies utilising the theories of reasoned action and planned behaviour.

    Science.gov (United States)

    McDermott, Máirtín S; Sharma, Rajeev

    2017-12-01

    The methods employed to measure behaviour in research testing the theories of reasoned action/planned behaviour (TRA/TPB) within the context of health behaviours have the potential to significantly bias findings. One bias yet to be examined in that literature is that due to common method variance (CMV). CMV introduces a variance in scores attributable to the method used to measure a construct, rather than the construct it represents. The primary aim of this study was to evaluate the impact of method bias on the associations of health behaviours with TRA/TPB variables. Data were sourced from four meta-analyses (177 studies). The method used to measure behaviour for each effect size was coded for susceptibility to bias. The moderating impact of method type was assessed using meta-regression. Method type significantly moderated the associations of intentions, attitudes and social norms with behaviour, but not that between perceived behavioural control and behaviour. The magnitude of the moderating effect of method type appeared consistent between cross-sectional and prospective studies, but varied across behaviours. The current findings strongly suggest that method bias significantly inflates associations in TRA/TPB research, and poses a potentially serious validity threat to the cumulative findings reported in that field.

  5. Bias Correction for the Maximum Likelihood Estimate of Ability. Research Report. ETS RR-05-15

    Science.gov (United States)

    Zhang, Jinming

    2005-01-01

    Lord's bias function and the weighted likelihood estimation method are effective in reducing the bias of the maximum likelihood estimate of an examinee's ability under the assumption that the true item parameters are known. This paper presents simulation studies to determine the effectiveness of these two methods in reducing the bias when the item…

  6. The generalizability of gender bias: Testing the effects of contextual, explicit, and implicit sexism on labor arbitration decisions.

    Science.gov (United States)

    Girvan, Erik J; Deason, Grace; Borgida, Eugene

    2015-10-01

    Decades of social-psychological research show that gender bias can result from features of the social context and from individual-level psychological predispositions. Do these sources of bias impact legal decisions, which are frequently made by people subject to factors that have been proposed to reduce bias (training and accountability)? To answer the question, we examined the potential for 3 major social-psychological theories of gender bias (role-congruity theory, ambivalent sexism, and implicit bias) to predict outcomes of labor arbitration decisions. In the first study, undergraduate students and professional arbitrators made decisions about 2 mock arbitration cases in which the gender of the employee-grievants was experimentally manipulated. Student participants' decisions showed the predicted gender bias, whereas the decisions of experienced professionals did not. Individual-level attitudes did not predict the extent of the observed bias and accountability did not attenuate it. In the second study, arbitrators' explicit and implicit gender attitudes were significant predictors of their decisions in published cases. The laboratory and field results suggest that context, expertise, and implicit and explicit attitudes are relevant to legal decision-making, but that laboratory experiments alone may not fully capture the nature of their effect on legal professionals' decisions in real cases. (c) 2015 APA, all rights reserved).

  7. Illustrating, Quantifying, and Correcting for Bias in Post-hoc Analysis of Gene-Based Rare Variant Tests of Association

    Directory of Open Access Journals (Sweden)

    Kelsey E. Grinde

    2017-09-01

    Full Text Available To date, gene-based rare variant testing approaches have focused on aggregating information across sets of variants to maximize statistical power in identifying genes showing significant association with diseases. Beyond identifying genes that are associated with diseases, the identification of causal variant(s in those genes and estimation of their effect is crucial for planning replication studies and characterizing the genetic architecture of the locus. However, we illustrate that straightforward single-marker association statistics can suffer from substantial bias introduced by conditioning on gene-based test significance, due to the phenomenon often referred to as “winner's curse.” We illustrate the ramifications of this bias on variant effect size estimation and variant prioritization/ranking approaches, outline parameters of genetic architecture that affect this bias, and propose a bootstrap resampling method to correct for this bias. We find that our correction method significantly reduces the bias due to winner's curse (average two-fold decrease in bias, p < 2.2 × 10−6 and, consequently, substantially improves mean squared error and variant prioritization/ranking. The method is particularly helpful in adjustment for winner's curse effects when the initial gene-based test has low power and for relatively more common, non-causal variants. Adjustment for winner's curse is recommended for all post-hoc estimation and ranking of variants after a gene-based test. Further work is necessary to continue seeking ways to reduce bias and improve inference in post-hoc analysis of gene-based tests under a wide variety of genetic architectures.

  8. A test of the transcription model for biased inheritance of yeast mitochondrial DNA.

    Science.gov (United States)

    Lorimer, H E; Brewer, B J; Fangman, W L

    1995-09-01

    Two strand-specific origins of replication appear to be required for mammalian mitochondrial DNA (mtDNA) replication. Structural equivalents of these origins are found in the rep sequences of Saccharomyces cerevisiae mtDNA. These striking similarities have contributed to a universal model for the initiation of mtDNA replication in which a primer is created by cleavage of an origin region transcript. Consistent with this model are the properties of deletion mutants of yeast mtDNA ([rho-]) with a high density of reps (HS [rho-]). These mutant mtDNAs are preferentially inherited by the progeny resulting from the mating of HS [rho-] cells with cells containing wild-type mtDNA ([rho+]). This bias is presumed to result from a replication advantage conferred on HS [rho-] mtDNA by the high density of rep sequences acting as origins. To test whether transcription is indeed required for the preferential inheritance of HS [rho-] mtDNA, we deleted the nuclear gene (RPO41) for the mitochondrial RNA polymerase, reducing transcripts by at least 1000-fold. Since [rho-] genomes, but not [rho+] genomes, are stable when RPO41 is deleted, we examined matings between HS [rho-] and neutral [rho-] cells. Neutral [rho-] mtDNAs lack rep sequences and are not preferentially inherited in [rho-] x [rho+] crosses. In HS [rho-] x neutral [rho-] matings, the HS [rho-] mtDNA was preferentially inherited whether both parents were wild type or both were deleted for RPO41. Thus, transcription from the rep promoter does not appear to be necessary for biased inheritance. Our results, and analysis of the literature, suggest that priming by transcription is not a universal mechanism for mtDNA replication initiation.

  9. Eye-movement evidence of the time-course of attentional bias for threatening pictures in test-anxious students

    NARCIS (Netherlands)

    Dong, Y.; Beuckelaer, A. de; Yu, L.; Zhou, R

    2017-01-01

    Protocols for measuring attentional bias to threat in test-anxiety, a special form of trait-anxiety, are rarely found in the literature. In our eye-tracking study, we introduced a new protocol, and studied the time-course of attention to test-related pictures with varying threat levels in 22 high

  10. A Cross-Cultural Test of Sex Bias in the Predictive Validity of Scholastic Aptitude Examinations: Some Israeli Findings.

    Science.gov (United States)

    Zeidner, Moshe

    1987-01-01

    This study examined the cross-cultural validity of the sex bias contention with respect to standardized aptitude testing, used for academic prediction purposes in Israel. Analyses were based on the grade point average and scores of 1778 Jewish and 1017 Arab students who were administered standardized college entrance test batteries. (Author/LMO)

  11. A unified factor-analytic approach to the detection of item and test bias: Illustration with the effect of providing calculators to students with dyscalculia

    Directory of Open Access Journals (Sweden)

    Lee, M. K.

    2016-01-01

    Full Text Available An absence of measurement bias against distinct groups is a prerequisite for the use of a given psychological instrument in scientific research or high-stakes assessment. Factor analysis is the framework explicitly adopted for the identification of such bias when the instrument consists of a multi-test battery, whereas item response theory is employed when the focus narrows to a single test composed of discrete items. Item response theory can be treated as a mild nonlinearization of the standard factor model, and thus the essential unity of bias detection at the two levels merits greater recognition. Here we illustrate the benefits of a unified approach with a real-data example, which comes from a statewide test of mathematics achievement where examinees diagnosed with dyscalculia were accommodated with calculators. We found that items that can be solved by explicit arithmetical computation became easier for the accommodated examinees, but the quantitative magnitude of this differential item functioning (measurement bias was small.

  12. Gender bias in clinical research, pharmaceutical marketing, and the prescription of drugs

    Directory of Open Access Journals (Sweden)

    Elisa Chilet-Rosell

    2014-12-01

    Full Text Available This thesis is part of the studies of gender bias in health which together with the paradigm of evidence-based medicine shares the empirical assumption that there are inaccuracies in medical practice, in addition to a lack of rigour and transparency. It worked with the distinction between the concepts of sex and gender and between the concepts of sex-related differences and gender inequalities, in terms of applying a gender perspective in the study design and the subsequent analysis. This PhD review presents the research process conducted in Spain, which can provide an example for future research. Study I described a review of 58 clinical trials (CTs of etoricoxib to assess its compliance with the Recommendations of Evaluation of Gender Differences in the Clinical Evaluation of Drugs. In Study II, key informants from professions related to different areas in drug development and pharmacovigilance held a working meeting to reach a consensus document on recommendations for the study and evaluation of gender differences in CTs in Spain. In Study III, the websites of the eight best-selling hormone replacement therapy drugs in Spain on Google first page of results were analysed. In Study IV, a logistic regression analysis was performed to compare analgesic prescription by sex in regions with a higher or lower Gender Development Index (GDI than the Spanish average. Gender biases identified in this thesis limited the legitimacy of medicine, which is not based on the best possible evidence. The results also demonstrate the existence of inequalities between men and women that are not due merely to biological differences, but are gender inequalities stemming from the social differences that exist between both sexes.

  13. Gender bias in clinical research, pharmaceutical marketing, and the prescription of drugs.

    Science.gov (United States)

    Chilet-Rosell, Elisa

    2014-01-01

    This thesis is part of the studies of gender bias in health which together with the paradigm of evidence-based medicine shares the empirical assumption that there are inaccuracies in medical practice, in addition to a lack of rigour and transparency. It worked with the distinction between the concepts of sex and gender and between the concepts of sex-related differences and gender inequalities, in terms of applying a gender perspective in the study design and the subsequent analysis. This PhD review presents the research process conducted in Spain, which can provide an example for future research. Study I described a review of 58 clinical trials (CTs) of etoricoxib to assess its compliance with the Recommendations of Evaluation of Gender Differences in the Clinical Evaluation of Drugs. In Study II, key informants from professions related to different areas in drug development and pharmacovigilance held a working meeting to reach a consensus document on recommendations for the study and evaluation of gender differences in CTs in Spain. In Study III, the websites of the eight best-selling hormone replacement therapy drugs in Spain on Google first page of results were analysed. In Study IV, a logistic regression analysis was performed to compare analgesic prescription by sex in regions with a higher or lower Gender Development Index (GDI) than the Spanish average. Gender biases identified in this thesis limited the legitimacy of medicine, which is not based on the best possible evidence. The results also demonstrate the existence of inequalities between men and women that are not due merely to biological differences, but are gender inequalities stemming from the social differences that exist between both sexes.

  14. Is Collaborative, Community-Engaged Scholarship More Rigorous than Traditional Scholarship? On Advocacy, Bias, and Social Science Research

    Science.gov (United States)

    Warren, Mark R.; Calderón, José; Kupscznk, Luke Aubry; Squires, Gregory; Su, Celina

    2018-01-01

    Contrary to the charge that advocacy-oriented research cannot meet social science research standards because it is inherently biased, the authors of this article argue that collaborative, community-engaged scholarship (CCES) must meet high standards of rigor if it is to be useful to support equity-oriented, social justice agendas. In fact, they…

  15. Biases in casino betting

    Directory of Open Access Journals (Sweden)

    James Sundali

    2006-07-01

    Full Text Available We examine two departures of individual perceptions of randomness from probability theory: the hot hand and the gambler's fallacy, and their respective opposites. This paper's first contribution is to use data from the field (individuals playing roulette in a casino to demonstrate the existence and impact of these biases that have been previously documented in the lab. Decisions in the field are consistent with biased beliefs, although we observe significant individual heterogeneity in the population. A second contribution is to separately identify these biases within a given individual, then to examine their within-person correlation. We find a positive and significant correlation across individuals between hot hand and gambler's fallacy biases, suggesting a common (root cause of the two related errors. We speculate as to the source of this correlation (locus of control, and suggest future research which could test this speculation.

  16. Risk of bias and confounding of observational studies of Zika virus infection: A scoping review of research protocols.

    Science.gov (United States)

    Reveiz, Ludovic; Haby, Michelle M; Martínez-Vega, Ruth; Pinzón-Flores, Carlos E; Elias, Vanessa; Smith, Emma; Pinart, Mariona; Broutet, Nathalie; Becerra-Posada, Francisco; Aldighieri, Sylvain; Van Kerkhove, Maria D

    2017-01-01

    Given the severity and impact of the current Zika virus (ZIKV) outbreak in the Americas, numerous countries have rushed to develop research studies to assess ZIKV and its potential health consequences. In an effort to ensure that studies are comprehensive, both internally and externally valid, and with reliable results, the World Health Organization, the Pan American Health Organization, Institut Pasteur, the networks of Fiocruz, the Consortia for the Standardization of Influenza Seroepidemiology (CONSISE) and the International Severe Acute Respiratory and Emerging Infection Consortium (ISARIC) have generated six standardized clinical and epidemiological research protocols and questionnaires to address key public health questions on ZIKV. We conducted a systematic search of ongoing study protocols related to ZIKV research. We analyzed the content of protocols of 32 cohort studies and 13 case control studies for systematic bias that could produce erroneous results. Additionally we aimed to characterize the risks of bias and confounding in observational studies related to ZIKV and to propose ways to minimize them, including the use of six newly standardized research protocols. Observational studies of ZIKV face an array of challenges, including measurement of exposure and outcomes (microcephaly and Guillain-Barré Syndrome). Potential confounders need to be measured where known and controlled for in the analysis. Selection bias due to non-random selection is a significant issue, particularly in the case-control design, and losses to follow-up is equally important for the cohort design. Observational research seeking to answer key questions on the ZIKV should consider these restrictions and take precautions to minimize bias in an effort to provide reliable and valid results. Utilization of the standardized research protocols developed by the WHO, PAHO, Institut Pasteur, and CONSISE will harmonize the key methodological aspects of each study design to minimize bias at

  17. Risk of bias and confounding of observational studies of Zika virus infection: A scoping review of research protocols.

    Directory of Open Access Journals (Sweden)

    Ludovic Reveiz

    Full Text Available Given the severity and impact of the current Zika virus (ZIKV outbreak in the Americas, numerous countries have rushed to develop research studies to assess ZIKV and its potential health consequences. In an effort to ensure that studies are comprehensive, both internally and externally valid, and with reliable results, the World Health Organization, the Pan American Health Organization, Institut Pasteur, the networks of Fiocruz, the Consortia for the Standardization of Influenza Seroepidemiology (CONSISE and the International Severe Acute Respiratory and Emerging Infection Consortium (ISARIC have generated six standardized clinical and epidemiological research protocols and questionnaires to address key public health questions on ZIKV.We conducted a systematic search of ongoing study protocols related to ZIKV research. We analyzed the content of protocols of 32 cohort studies and 13 case control studies for systematic bias that could produce erroneous results. Additionally we aimed to characterize the risks of bias and confounding in observational studies related to ZIKV and to propose ways to minimize them, including the use of six newly standardized research protocols.Observational studies of ZIKV face an array of challenges, including measurement of exposure and outcomes (microcephaly and Guillain-Barré Syndrome. Potential confounders need to be measured where known and controlled for in the analysis. Selection bias due to non-random selection is a significant issue, particularly in the case-control design, and losses to follow-up is equally important for the cohort design.Observational research seeking to answer key questions on the ZIKV should consider these restrictions and take precautions to minimize bias in an effort to provide reliable and valid results. Utilization of the standardized research protocols developed by the WHO, PAHO, Institut Pasteur, and CONSISE will harmonize the key methodological aspects of each study design to

  18. Decision-making in research tasks with sequential testing.

    Directory of Open Access Journals (Sweden)

    Thomas Pfeiffer

    Full Text Available BACKGROUND: In a recent controversial essay, published by JPA Ioannidis in PLoS Medicine, it has been argued that in some research fields, most of the published findings are false. Based on theoretical reasoning it can be shown that small effect sizes, error-prone tests, low priors of the tested hypotheses and biases in the evaluation and publication of research findings increase the fraction of false positives. These findings raise concerns about the reliability of research. However, they are based on a very simple scenario of scientific research, where single tests are used to evaluate independent hypotheses. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we present computer simulations and experimental approaches for analyzing more realistic scenarios. In these scenarios, research tasks are solved sequentially, i.e. subsequent tests can be chosen depending on previous results. We investigate simple sequential testing and scenarios where only a selected subset of results can be published and used for future rounds of test choice. Results from computer simulations indicate that for the tasks analyzed in this study, the fraction of false among the positive findings declines over several rounds of testing if the most informative tests are performed. Our experiments show that human subjects frequently perform the most informative tests, leading to a decline of false positives as expected from the simulations. CONCLUSIONS/SIGNIFICANCE: For the research tasks studied here, findings tend to become more reliable over time. We also find that the performance in those experimental settings where not all performed tests could be published turned out to be surprisingly inefficient. Our results may help optimize existing procedures used in the practice of scientific research and provide guidance for the development of novel forms of scholarly communication.

  19. Potential biases in colorectal cancer screening using faecal occult blood test

    DEFF Research Database (Denmark)

    Riboe, Dea Grip; Dogan, Tilde Steen; Brodersen, John

    2013-01-01

    of this paper was to scrutinize these trials for potential biases and assess their influence on the screening trials. METHODS: The four RCTs were reviewed based on the principles of 'Critical Appraisal of the Medical Literature'. Principal investigators of the four RCTs were contacted to clarify uncertainties...... in their study. Data were collected from The Danish Data Archives. Authors of the Cochrane review were contacted. RESULTS: Six biases were identified, of which five favour screening. Three of the biases identified were specific to CRC screening: type of diagnostic method, place of surgery and diagnostic delay....... CONCLUSION: The 16% RRR in CRC mortality found in the updated Cochrane review's meta-analysis is overestimated....

  20. Methodological Issues in Cross-Cultural Counseling Research: Equivalence, Bias, and Translations

    Science.gov (United States)

    Aegisdottir, Stefania; Gerstein, Lawrence A.; Cinarbas, Deniz Canel

    2008-01-01

    Concerns about the cross-cultural validity of constructs are discussed, including equivalence, bias, and translation procedures. Methods to enhance equivalence are described, as are strategies to evaluate and minimize types of bias. Recommendations for translating instruments are also presented. To illustrate some challenges of cross-cultural…

  1. A Classroom Demonstration of Potential Biases in the Subjective Interpretation of Projective Tests.

    Science.gov (United States)

    Wiederman, Michael W.

    1999-01-01

    Suggests that instructors teaching psychological assessment can use a demonstration to illustrate potential biases when subjectively interpreting response to projective stimuli. Outlines the classroom procedure, notes styles of learning involved, and presents a summary of student evaluations. (DSK)

  2. Possible Solution to Publication Bias Through Bayesian Statistics, Including Proper Null Hypothesis Testing

    NARCIS (Netherlands)

    Konijn, Elly A.; van de Schoot, Rens; Winter, Sonja D.; Ferguson, Christopher J.

    2015-01-01

    The present paper argues that an important cause of publication bias resides in traditional frequentist statistics forcing binary decisions. An alternative approach through Bayesian statistics provides various degrees of support for any hypothesis allowing balanced decisions and proper null

  3. The relationship between study sponsorship, risks of bias, and research outcomes in atrazine exposure studies conducted in non-human animals: Systematic review and meta-analysis.

    Science.gov (United States)

    Bero, L; Anglemyer, A; Vesterinen, H; Krauth, D

    2016-01-01

    A critical component of systematic review methodology is the assessment of the risks of bias of studies that are included in the review. There is controversy about whether funding source should be included in a risk of bias assessment of animal toxicology studies. To determine whether industry research sponsorship is associated with methodological biases, the results, or conclusions of animal studies examining the effect of exposure to atrazine on reproductive or developmental outcomes. We searched multiple electronic databases and the reference lists of relevant articles to identify original research studies examining the effect of any dose of atrazine exposure at any life stage on reproduction or development in non-human animals. We compared methodological risks of bias, the conclusions of the studies, the statistical significance of the findings, and the magnitude of effect estimates between industry sponsored and non-industry sponsored studies. Fifty-one studies met the inclusion criteria. There were no differences in methodological risks of bias in industry versus non-industry sponsored studies. 39 studies tested environmentally relevant concentrations of atrazine (11 industry sponsored, 24 non-industry sponsored, 4 with no funding disclosures). Non-industry sponsored studies (12/24, 50.0%) were more likely to conclude that atrazine was harmful compared to industry sponsored studies (2/11, 18.1%) (p value=0.07). A higher proportion of non-industry sponsored studies reported statistically significant harmful effects (8/24, 33.3%) compared to industry-sponsored studies (1/11; 9.1%) (p value=0.13). The association of industry sponsorship with decreased effect sizes for harm outcomes was inconclusive. Our findings support the inclusion of research sponsorship as a risk of bias criterion in tools used to assess risks of bias in animal studies for systematic reviews. The reporting of other empirically based risk of bias criteria for animal studies, such as blinded

  4. Bias associated with delayed verification in test accuracy studies: accuracy of tests for endometrial hyperplasia may be much higher than we think!

    Directory of Open Access Journals (Sweden)

    Coomarasamy Aravinthan

    2004-05-01

    Full Text Available Abstract Background To empirically evaluate bias in estimation of accuracy associated with delay in verification of diagnosis among studies evaluating tests for predicting endometrial hyperplasia. Methods Systematic reviews of all published research on accuracy of miniature endometrial biopsy and endometr ial ultrasonography for diagnosing endometrial hyperplasia identified 27 test accuracy studies (2,982 subjects. Of these, 16 had immediate histological verification of diagnosis while 11 had verification delayed > 24 hrs after testing. The effect of delay in verification of diagnosis on estimates of accuracy was evaluated using meta-regression with diagnostic odds ratio (dOR as the accuracy measure. This analysis was adjusted for study quality and type of test (miniature endometrial biopsy or endometrial ultrasound. Results Compared to studies with immediate verification of diagnosis (dOR 67.2, 95% CI 21.7–208.8, those with delayed verification (dOR 16.2, 95% CI 8.6–30.5 underestimated the diagnostic accuracy by 74% (95% CI 7%–99%; P value = 0.048. Conclusion Among studies of miniature endometrial biopsy and endometrial ultrasound, diagnostic accuracy is considerably underestimated if there is a delay in histological verification of diagnosis.

  5. Research on injury compensation and health outcomes: ignoring the problem of reverse causality led to a biased conclusion.

    Science.gov (United States)

    Spearing, Natalie M; Connelly, Luke B; Nghiem, Hong S; Pobereskin, Louis

    2012-11-01

    This study highlights the serious consequences of ignoring reverse causality bias in studies on compensation-related factors and health outcomes and demonstrates a technique for resolving this problem of observational data. Data from an English longitudinal study on factors, including claims for compensation, associated with recovery from neck pain (whiplash) after rear-end collisions are used to demonstrate the potential for reverse causality bias. Although it is commonly believed that claiming compensation leads to worse recovery, it is also possible that poor recovery may lead to compensation claims--a point that is seldom considered and never addressed empirically. This pedagogical study compares the association between compensation claiming and recovery when reverse causality bias is ignored and when it is addressed, controlling for the same observable factors. When reverse causality is ignored, claimants appear to have a worse recovery than nonclaimants; however, when reverse causality bias is addressed, claiming compensation appears to have a beneficial effect on recovery, ceteris paribus. To avert biased policy and judicial decisions that might inadvertently disadvantage people with compensable injuries, there is an urgent need for researchers to address reverse causality bias in studies on compensation-related factors and health. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. Flight Test Approach to Adaptive Control Research

    Science.gov (United States)

    Pavlock, Kate Maureen; Less, James L.; Larson, David Nils

    2011-01-01

    The National Aeronautics and Space Administration s Dryden Flight Research Center completed flight testing of adaptive controls research on a full-scale F-18 testbed. The validation of adaptive controls has the potential to enhance safety in the presence of adverse conditions such as structural damage or control surface failures. This paper describes the research interface architecture, risk mitigations, flight test approach and lessons learned of adaptive controls research.

  7. Bias magnetic field and test period dependences of direct and converse magnetoelectric hysteresis of tri-layered magnetoelectric composite

    Science.gov (United States)

    Zhou, Yun; Li, Xiao-Hong; Wang, Jian-Feng; Zhou, Hao-Miao; Cao, Dan; Jiao, Zhi-Wei; Xu, Long; Li, Qi-Hao

    2018-04-01

    The direct and converse magnetoelectric hysteresis behavior for a tri-layered composite has been comparatively investigated and significant similarities have been observed. The results show that both the direct and converse magnetoelectric hysteresis is deeply affected by the bias magnetic field and test period. The test time hysteresis caused by a fast varying bias magnetic field can be reduced by prolonging the test period. The observed coercive field, remanence, and ratio of remanence of the direct and converse magnetoelectric effects with the test period obey an exponential decay law. A hysteretic nonlinear magnetoelectric theoretical model for the symmetrical tri-layered structure has been proposed based on a nonlinear constitutive model and pinning effect. The numerical calculation shows that the theoretical results are in good agreement with the experimental results. These findings not only provide insight into the examination and practical applications of magnetoelectric materials, but also propose a theoretical frame for studying the hysteretic characteristics of the magnetoelectric effect.

  8. A checklist to facilitate objective hypothesis testing in social psychology research.

    Science.gov (United States)

    Washburn, Anthony N; Morgan, G Scott; Skitka, Linda J

    2015-01-01

    Social psychology is not a very politically diverse area of inquiry, something that could negatively affect the objectivity of social psychological theory and research, as Duarte et al. argue in the target article. This commentary offers a number of checks to help researchers uncover possible biases and identify when they are engaging in hypothesis confirmation and advocacy instead of hypothesis testing.

  9. Chinese Beliefs in Luck are Linked to Gambling Problems via Strengthened Cognitive Biases: A Mediation Test.

    Science.gov (United States)

    Lim, Matthew S M; Rogers, Robert D

    2017-12-01

    Problematic patterns of gambling and their harms are known to have culturally specific expressions. For ethnic Chinese people, patterns of superstitious belief in this community appear to be linked to the elevated rates of gambling-related harms; however, little is known about the mediating psychological mechanisms. To address this issue, we surveyed 333 Chinese gamblers residing internationally and used a mediation analysis to explore how gambling-related cognitive biases, gambling frequency and variety of gambling forms ('scope') mediate the association between beliefs in luck and gambling problems. We found that cognitive biases and scope were significant mediators of this link but that the former is a stronger mediator than the latter. The mediating erroneous beliefs were not specific to any particular type of cognitive bias. These results suggest that Chinese beliefs in luck are expressed as gambling cognitive biases that increase the likelihood of gambling problems, and that biases that promote gambling (and its harms) are best understood within their socio-cultural context.

  10. Confirmation bias in studies of nestmate recognition: a cautionary note for research into the behaviour of animals.

    Directory of Open Access Journals (Sweden)

    Ellen van Wilgenburg

    Full Text Available Confirmation bias is a tendency of people to interpret information in a way that confirms their expectations. A long recognized phenomenon in human psychology, confirmation bias can distort the results of a study and thus reduce its reliability. While confirmation bias can be avoided by conducting studies blind to treatment groups, this practice is not always used. Surprisingly, this is true of research in animal behaviour, and the extent to which confirmation bias influences research outcomes in this field is rarely investigated. Here we conducted a meta-analysis, using studies on nestmate recognition in ants, to compare the outcomes of studies that were conducted blind with those that were not. Nestmate recognition studies typically perform intra- and inter colony aggression assays, with the a priori expectation that there should be little or no aggression among nestmates. Aggressive interactions between ants can include subtle behaviours such as mandible flaring and recoil, which can be hard to quantify, making these types of assays prone to confirmation bias. Our survey revealed that only 29% of our sample of 79 studies were conducted blind. These studies were more likely to report aggression among nestmates if they were conducted blind (73% than if they were not (21%. Moreover, we found that the effect size between nestmate and non-nestmate treatment means is significantly lower in experiments conducted blind than those in which colony identity is known (1.38 versus 2.76. We discuss the implications of the impact of confirmation bias for research that attempts to obtain quantitative synthesises of data from different studies.

  11. Confirmation bias in studies of nestmate recognition: a cautionary note for research into the behaviour of animals.

    Science.gov (United States)

    van Wilgenburg, Ellen; Elgar, Mark A

    2013-01-01

    Confirmation bias is a tendency of people to interpret information in a way that confirms their expectations. A long recognized phenomenon in human psychology, confirmation bias can distort the results of a study and thus reduce its reliability. While confirmation bias can be avoided by conducting studies blind to treatment groups, this practice is not always used. Surprisingly, this is true of research in animal behaviour, and the extent to which confirmation bias influences research outcomes in this field is rarely investigated. Here we conducted a meta-analysis, using studies on nestmate recognition in ants, to compare the outcomes of studies that were conducted blind with those that were not. Nestmate recognition studies typically perform intra- and inter colony aggression assays, with the a priori expectation that there should be little or no aggression among nestmates. Aggressive interactions between ants can include subtle behaviours such as mandible flaring and recoil, which can be hard to quantify, making these types of assays prone to confirmation bias. Our survey revealed that only 29% of our sample of 79 studies were conducted blind. These studies were more likely to report aggression among nestmates if they were conducted blind (73%) than if they were not (21%). Moreover, we found that the effect size between nestmate and non-nestmate treatment means is significantly lower in experiments conducted blind than those in which colony identity is known (1.38 versus 2.76). We discuss the implications of the impact of confirmation bias for research that attempts to obtain quantitative synthesises of data from different studies.

  12. Colloid research for the Nevada Test Site

    International Nuclear Information System (INIS)

    Bryant, E.A.

    1992-05-01

    Research is needed to understand the role of particulates in the migration of radionuclides away from the sites of nuclear tests at the Nevada Test Site. The process of testing itself may produce a reservoir of particles to serve as vectors for the transport of long-lived radionuclides in groundwater. Exploratory experiments indicate the presence of numerous particulates in the vicinity of the Cambric test but a much lower loading in a nearby well that has been pumped continuously for 15 years. Recent groundwater colloid research is briefly reviewed to identify sampling and characterization methods that may be applicable at the Nevada Test Site

  13. Vacuum decay container/closure integrity testing technology. Part 1. ASTM F2338-09 precision and bias studies.

    Science.gov (United States)

    Wolf, Heinz; Stauffer, Tony; Chen, Shu-Chen Y; Lee, Yoojin; Forster, Ronald; Ludzinski, Miron; Kamat, Madhav; Godorov, Phillip; Guazzo, Dana Morton

    2009-01-01

    ASTM F2338-09 Standard Test Method for Nondestructive Detection of Leaks in Packages by Vacuum Decay Method is applicable for leak-testing rigid and semi-rigid non-lidded trays; trays or cups sealed with porous barrier lidding materials; rigid, nonporous packages; and flexible, nonporous packages. Part 1 of this series describes the precision and bias studies performed in 2008 to expand this method's scope to include rigid, nonporous packages completely or partially filled with liquid. Round robin tests using three VeriPac 325/LV vacuum decay leak testers (Packaging Technologies & Inspection, LLC, Tuckahoe, NY) were performed at three test sites. Test packages were 1-mL glass syringes. Positive controls had laser-drilled holes in the barrel ranging from about 5 to 15 microm in nominal diameter. Two different leak tests methods were performed at each site: a "gas leak test" performed at 250 mbar (absolute) and a "liquid leak test" performed at about 1 mbar (absolute). The gas leak test was used to test empty, air-filled syringes. All defects with holes > or = 5.0 microm and all no-defect controls were correctly identified. The only false negative result was attributed to a single syringe with a ASTM F2338-09 test method and the precision and bias study report are available by contacting ASTM International in West Conshohocken, PA, USA (www.astm.org).

  14. Testing human sperm chemotaxis: how to detect biased motion in population assays.

    Directory of Open Access Journals (Sweden)

    Leah Armon

    Full Text Available Biased motion of motile cells in a concentration gradient of a chemoattractant is frequently studied on the population level. This approach has been particularly employed in human sperm chemotactic assays, where the fraction of responsive cells is low and detection of biased motion depends on subtle differences. In these assays, statistical measures such as population odds ratios of swimming directions can be employed to infer chemotactic performance. Here, we report on an improved method to assess statistical significance of experimentally determined odds ratios and discuss the strong impact of data correlations that arise from the directional persistence of sperm swimming.

  15. A test matrix sequencer for research test facility automation

    Science.gov (United States)

    Mccartney, Timothy P.; Emery, Edward F.

    1990-01-01

    The hardware and software configuration of a Test Matrix Sequencer, a general purpose test matrix profiler that was developed for research test facility automation at the NASA Lewis Research Center, is described. The system provides set points to controllers and contact closures to data systems during the course of a test. The Test Matrix Sequencer consists of a microprocessor controlled system which is operated from a personal computer. The software program, which is the main element of the overall system is interactive and menu driven with pop-up windows and help screens. Analog and digital input/output channels can be controlled from a personal computer using the software program. The Test Matrix Sequencer provides more efficient use of aeronautics test facilities by automating repetitive tasks that were once done manually.

  16. Test Framing Generates a Stability Bias for Predictions of Learning by Causing People to Discount their Learning Beliefs

    Science.gov (United States)

    Ariel, Robert; Hines, Jarrod C.; Hertzog, Christopher

    2014-01-01

    People estimate minimal changes in learning when making predictions of learning (POLs) for future study opportunities despite later showing increased performance and an awareness of that increase (Kornell & Bjork, 2009). This phenomenon is conceptualized as a stability bias in judgments about learning. We investigated the malleability of this effect, and whether it reflected people’s underlying beliefs about learning. We manipulated prediction framing to emphasize the role of testing vs. studying on memory and directly measured beliefs about multi-trial study effects on learning by having participants construct predicted learning curves before and after the experiment. Mean POLs were more sensitive to the number of study-test opportunities when performance was framed in terms of study benefits rather than testing benefits and POLs reflected pre-existing beliefs about learning. The stability bias is partially due to framing and reflects discounted beliefs about learning benefits rather than inherent belief in the stability of performance. PMID:25067885

  17. Benefits of being biased!

    Indian Academy of Sciences (India)

    Administrator

    Journal of Genetics, Vol. 83, No. 2, August 2004. Keywords. codon bias; alcohol dehydrogenase; Darwinian ... RESEARCH COMMENTARY. Benefits of being biased! SUTIRTH DEY*. Evolutionary Biology Laboratory, Evolutionary & Organismal Biology Unit,. Jawaharlal Nehru Centre for Advanced Scientific Research,.

  18. The Ranschburg Effect: Tests of the Guessing-Bias and Proactive Interference Hypotheses

    Science.gov (United States)

    Walsh, Michael F.; Schwartz, Marian

    1977-01-01

    The guessing-bias and proactive interference hypotheses of the Ranschburg Effect were investigated by giving three groups different instructions as to guessing during recall. Results failed to support the prediction that the effect should be reduced or eliminated on shift trials. Neither hypothesis received significant support. (CHK)

  19. Can health workers reliably assess their own work? A test-retest study of bias among data collectors conducting a Lot Quality Assurance Sampling survey in Uganda.

    Science.gov (United States)

    Beckworth, Colin A; Davis, Rosemary H; Faragher, Brian; Valadez, Joseph J

    2015-03-01

    Lot Quality Assurance Sampling (LQAS) is a classification method that enables local health staff to assess health programmes for which they are responsible. While LQAS has been favourably reviewed by the World Bank and World Health Organization (WHO), questions remain about whether using local health staff as data collectors can lead to biased data. In this test-retest research, Pallisa Health District in Uganda is subdivided into four administrative units called supervision areas (SA). Data collectors from each SA conducted an LQAS survey. A week later, the data collectors were swapped to a different SA, outside their area of responsibility, to repeat the LQAS survey with the same respondents. The two data sets were analysed for agreement using Cohens' kappa coefficient and disagreements were analysed. Kappa values ranged from 0.19 to 0.97. On average, there was a moderate degree of agreement for knowledge indicators and a substantial level for practice indicators. Respondents were found to be systematically more knowledgeable on retest indicating bias favouring the retest, although no evidence of bias was found for practices indicators. In this initial study, using local health care providers to collect data did not bias data collection. The bias observed in the knowledge indicators is most likely due to the 'practice effect', whereby respondents increased their knowledge as a result of completing the first survey, as no corresponding effect was seen in the practices indicators. Published by Oxford University Press in association with The London School of Hygiene and Tropical Medicine © The Author 2014; all rights reserved.

  20. Avoiding bias in medical ethical decision-making. Lessons to be learnt from psychology research.

    Science.gov (United States)

    Albisser Schleger, Heidi; Oehninger, Nicole R; Reiter-Theil, Stella

    2011-05-01

    When ethical decisions have to be taken in critical, complex medical situations, they often involve decisions that set the course for or against life-sustaining treatments. Therefore the decisions have far-reaching consequences for the patients, their relatives, and often for the clinical staff. Although the rich psychology literature provides evidence that reasoning may be affected by undesired influences that may undermine the quality of the decision outcome, not much attention has been given to this phenomenon in health care or ethics consultation. In this paper, we aim to contribute to the sensitization of the problem of systematic reasoning biases by showing how exemplary individual and group biases can affect the quality of decision-making on an individual and group level. We are addressing clinical ethicists as well as clinicians who guide complex decision-making processes of ethical significance. Knowledge regarding exemplary group psychological biases (e.g. conformity bias), and individual biases (e.g. stereotypes), will be taken from the disciplines of social psychology and cognitive decision science and considered in the field of ethical decision-making. Finally we discuss the influence of intuitive versus analytical (systematical) reasoning on the validity of ethical decision-making.

  1. A permutation test to analyse systematic bias and random measurement errors of medical devices via boosting location and scale models.

    Science.gov (United States)

    Mayr, Andreas; Schmid, Matthias; Pfahlberg, Annette; Uter, Wolfgang; Gefeller, Olaf

    2017-06-01

    Measurement errors of medico-technical devices can be separated into systematic bias and random error. We propose a new method to address both simultaneously via generalized additive models for location, scale and shape (GAMLSS) in combination with permutation tests. More precisely, we extend a recently proposed boosting algorithm for GAMLSS to provide a test procedure to analyse potential device effects on the measurements. We carried out a large-scale simulation study to provide empirical evidence that our method is able to identify possible sources of systematic bias as well as random error under different conditions. Finally, we apply our approach to compare measurements of skin pigmentation from two different devices in an epidemiological study.

  2. Standard guide for preparing and interpreting precision and bias statements in test method standards used in the nuclear industry

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1992-01-01

    1.1 This guide covers terminology useful for the preparation and interpretation of precision and bias statements. 1.2 In formulating precision and bias statements, it is important to understand the statistical concepts involved and to identify the major sources of variation that affect results. Appendix X1 provides a brief summary of these concepts. 1.3 To illustrate the statistical concepts and to demonstrate some sources of variation, a hypothetical data set has been analyzed in Appendix X2. Reference to this example is made throughout this guide. 1.4 It is difficult and at times impossible to ship nuclear materials for interlaboratory testing. Thus, precision statements for test methods relating to nuclear materials will ordinarily reflect only within-laboratory variation.

  3. Testing the Large-scale Environments of Cool-core and Non-cool-core Clusters with Clustering Bias

    Energy Technology Data Exchange (ETDEWEB)

    Medezinski, Elinor; Battaglia, Nicholas; Cen, Renyue; Gaspari, Massimo; Strauss, Michael A.; Spergel, David N. [Department of Astrophysical Sciences, 4 Ivy Lane, Princeton, NJ 08544 (United States); Coupon, Jean, E-mail: elinorm@astro.princeton.edu [Department of Astronomy, University of Geneva, ch. dEcogia 16, CH-1290 Versoix (Switzerland)

    2017-02-10

    There are well-observed differences between cool-core (CC) and non-cool-core (NCC) clusters, but the origin of this distinction is still largely unknown. Competing theories can be divided into internal (inside-out), in which internal physical processes transform or maintain the NCC phase, and external (outside-in), in which the cluster type is determined by its initial conditions, which in turn leads to different formation histories (i.e., assembly bias). We propose a new method that uses the relative assembly bias of CC to NCC clusters, as determined via the two-point cluster-galaxy cross-correlation function (CCF), to test whether formation history plays a role in determining their nature. We apply our method to 48 ACCEPT clusters, which have well resolved central entropies, and cross-correlate with the SDSS-III/BOSS LOWZ galaxy catalog. We find that the relative bias of NCC over CC clusters is b = 1.42 ± 0.35 (1.6 σ different from unity). Our measurement is limited by the small number of clusters with core entropy information within the BOSS footprint, 14 CC and 34 NCC clusters. Future compilations of X-ray cluster samples, combined with deep all-sky redshift surveys, will be able to better constrain the relative assembly bias of CC and NCC clusters and determine the origin of the bimodality.

  4. Testing the Large-scale Environments of Cool-core and Non-cool-core Clusters with Clustering Bias

    International Nuclear Information System (INIS)

    Medezinski, Elinor; Battaglia, Nicholas; Cen, Renyue; Gaspari, Massimo; Strauss, Michael A.; Spergel, David N.; Coupon, Jean

    2017-01-01

    There are well-observed differences between cool-core (CC) and non-cool-core (NCC) clusters, but the origin of this distinction is still largely unknown. Competing theories can be divided into internal (inside-out), in which internal physical processes transform or maintain the NCC phase, and external (outside-in), in which the cluster type is determined by its initial conditions, which in turn leads to different formation histories (i.e., assembly bias). We propose a new method that uses the relative assembly bias of CC to NCC clusters, as determined via the two-point cluster-galaxy cross-correlation function (CCF), to test whether formation history plays a role in determining their nature. We apply our method to 48 ACCEPT clusters, which have well resolved central entropies, and cross-correlate with the SDSS-III/BOSS LOWZ galaxy catalog. We find that the relative bias of NCC over CC clusters is b = 1.42 ± 0.35 (1.6 σ different from unity). Our measurement is limited by the small number of clusters with core entropy information within the BOSS footprint, 14 CC and 34 NCC clusters. Future compilations of X-ray cluster samples, combined with deep all-sky redshift surveys, will be able to better constrain the relative assembly bias of CC and NCC clusters and determine the origin of the bimodality.

  5. Direct testing of the biasing effect of manipulations of endolymphatic pressure on cochlear mechanical function

    Science.gov (United States)

    LePage, Eric; Avan, Paul

    2015-12-01

    The history of cochlear mechanical investigations has been carried out in two largely separate sets of endeavours; those interested in auditory processing in animal models and those interested in the origin of adverse vestibular symptoms in humans. In respect of the first, mechanical vibratory data is considered pathological and not representative of pristine behaviour if it departs from the reigning model of sharp tuning and high hearing sensitivity. Conversely, when the description of the pathological behaviour is the focus, fluid movements responsible for hearing loss and vestibular symptoms dominate. Yet both extensive sets of data possess a common factor now being reconsidered for its potential to shed light on the mechanisms in general. The common factor is a mechanical bias — the departure of cochlear epithelial membranes from their usual resting position. In both cases the bias modulates hearing sensitivity and distorts tuning characteristics. Indeed several early sets of guinea pig mechanical data were dismissed as "pathological" when in hindsight, the primary effect influencing the data was not loss of outer hair cell function per se, but a mechanical bias unknowingly introduced in process of making the measurement. Such biases in the displacement of the basilar membrane from its position are common, and may be caused by low-frequency sounds (topically including infrasound) or by variations in fluid volume in the chambers particularly applying the case of endolymphatic hydrops. Most biases are quantified in terms of visualisation of fluid volume change, electric potential changes and otoacoustic emissions. Notably many previous studies have also searched for raised pressures with negative results. Yet these repeated findings are contrary to the widespread notion that, at least when homeostasis is lost, it is a rise in endolymphatic pressure which is responsible for membrane rupture and Meniere's attacks. This current investigation in Mongolian gerbils

  6. Bias and misleading concepts in an Arnica research study. Comments to improve experimental Homeopathy

    Directory of Open Access Journals (Sweden)

    Salvatore Chirumbolo

    2018-01-01

    Full Text Available Basic experimental models in Homeopathy are of major interest because they could get insightful data about the ability of high dilutions to work in a biological system. Due to the extreme difficulty in the highlighting any possible effect and trusting its reliability, methods should be particularly stringent and highly standardized. Confounders, handling process, pre-analytical errors, misleading statistics and misinterpretations may lead to experimental biases. This article tries to elucidate those factors causing bias, taking into account some recent reported evidence in the field.

  7. Anti-Atheist Bias in the United States: Testing Two Critical Assumptions

    OpenAIRE

    Swan, Lawton K; Heesacker, Martin

    2012-01-01

    Decades of opinion polling and empirical investigations have clearly demonstrated a pervasive anti-atheist prejudice in the United States. However, much of this scholarship relies on two critical and largely unaddressed assumptions: (a) that when people report negative attitudes toward atheists, they do so because they are reacting specifically to their lack of belief in God; and (b) that survey questions asking about attitudes toward atheists as a group yield reliable information about biase...

  8. Self-objectification, weight bias internalization, and binge eating in young women: Testing a mediational model.

    Science.gov (United States)

    Mehak, Adrienne; Friedman, Aliza; Cassin, Stephanie E

    2018-03-01

    Self-objectification and weight bias internalization are two internalization processes that are positively correlated with binge eating among young women. However, the mechanisms underlying these relationships are understudied. Consistent with objectification theory, this study examined appearance anxiety and body shame as mediators between self-objectification, weight bias internalization and binge eating. Female undergraduates (N=102) completed self-report measures of self-objectification, weight bias internalization, appearance anxiety, body shame, and binge eating. Results indicated that women who self-objectified and internalized negative weight-related attitudes reported greater binge eating (r s =.43 and r s =.57, respectively) and these associations were mediated by the combined effects of body shame and appearance anxiety. The contrast between the two mediators was also significant, such that body shame emerged as a stronger mediator within both mediational models. Results demonstrated that these internalization processes contribute to negative affect in young women, which may in turn lead to binge eating. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Measurement Error and Bias in Value-Added Models. Research Report. ETS RR-17-25

    Science.gov (United States)

    Kane, Michael T.

    2017-01-01

    By aggregating residual gain scores (the differences between each student's current score and a predicted score based on prior performance) for a school or a teacher, value-added models (VAMs) can be used to generate estimates of school or teacher effects. It is known that random errors in the prior scores will introduce bias into predictions of…

  10. Possible Biases of Researchers' Attitudes Toward Video Games: Publication Trends Analysis of the Medical Literature (1980-2013).

    Science.gov (United States)

    Segev, Aviv; Rovner, Mitchell; Appel, David Ian; Abrams, Aaron W; Rotem, Michal; Bloch, Yuval

    2016-07-18

    The study of video games is expanding, and so is the debate regarding their possible positive and deleterious effects. As controversies continue, several researchers have expressed their concerns about substantial biases existing in the field, which might lead to the creation of a skewed picture, both in the professional and in the lay literature. However, no study has tried to examine this issue quantitatively. The objective of our study was to examine possible systematic biases in the literature, by analyzing the publication trends of the medical and life sciences literature regarding video games. We performed a complete and systematic PubMed search up to December 31, 2013. We assessed all 1927 articles deemed relevant for their attitude toward video games according to the focus, hypothesis, and authors' interpretation of the study results, using a 3-category outcome (positive, negative, and neutral). We assessed the prevalence of different attitudes for possible association with year of publication, location of researchers, academic discipline, methodological research, and centrality of the publishing journals. The attitude toward video games presented in publications varied by year of publication, location, academic discipline, and methodological research applied (Pimpact factor (Pvideo games. Readers, both lay and professional, should weigh these contextual variables when interpreting studies' results, in light of the possible bias they carry. The results also support a need for a more balanced, open-minded approach toward video games, as it is likely that this complex phenomenon carries novel opportunities as well as new hazards.

  11. Commentary: Racism and Bias in Health Professions Education: How Educators, Faculty Developers, and Researchers Can Make a Difference.

    Science.gov (United States)

    Karani, Reena; Varpio, Lara; May, Win; Horsley, Tanya; Chenault, John; Miller, Karen Hughes; O'Brien, Bridget

    2017-11-01

    The Research in Medical Education (RIME) Program Planning Committee is committed to advancing scholarship in and promoting dialogue about the critical issues of racism and bias in health professions education (HPE). From the call for studies focused on underrepresented learners and faculty in medicine to the invited 2016 RIME plenary address by Dr. Camara Jones, the committee strongly believes that dismantling racism is critical to the future of HPE.The evidence is glaring: Dramatic racial and ethnic health disparities persist in the United States, people of color remain deeply underrepresented in medical school and academic health systems as faculty, learner experiences across the medical education continuum are fraught with bias, and current approaches to teaching perpetuate stereotypes and insufficiently challenge structural inequities. To achieve racial justice in HPE, academic medicine must commit to leveraging positions of influence and contributing from these positions. In this Commentary, the authors consider three roles (educator, faculty developer, and researcher) represented by the community of scholars and pose potential research questions as well as suggestions for advancing educational research relevant to eliminating racism and bias in HPE.

  12. Bias in logistic regression due to imperfect diagnostic test results and practical correction approaches.

    Science.gov (United States)

    Valle, Denis; Lima, Joanna M Tucker; Millar, Justin; Amratia, Punam; Haque, Ubydul

    2015-11-04

    Logistic regression is a statistical model widely used in cross-sectional and cohort studies to identify and quantify the effects of potential disease risk factors. However, the impact of imperfect tests on adjusted odds ratios (and thus on the identification of risk factors) is under-appreciated. The purpose of this article is to draw attention to the problem associated with modelling imperfect diagnostic tests, and propose simple Bayesian models to adequately address this issue. A systematic literature review was conducted to determine the proportion of malaria studies that appropriately accounted for false-negatives/false-positives in a logistic regression setting. Inference from the standard logistic regression was also compared with that from three proposed Bayesian models using simulations and malaria data from the western Brazilian Amazon. A systematic literature review suggests that malaria epidemiologists are largely unaware of the problem of using logistic regression to model imperfect diagnostic test results. Simulation results reveal that statistical inference can be substantially improved when using the proposed Bayesian models versus the standard logistic regression. Finally, analysis of original malaria data with one of the proposed Bayesian models reveals that microscopy sensitivity is strongly influenced by how long people have lived in the study region, and an important risk factor (i.e., participation in forest extractivism) is identified that would have been missed by standard logistic regression. Given the numerous diagnostic methods employed by malaria researchers and the ubiquitous use of logistic regression to model the results of these diagnostic tests, this paper provides critical guidelines to improve data analysis practice in the presence of misclassification error. Easy-to-use code that can be readily adapted to WinBUGS is provided, enabling straightforward implementation of the proposed Bayesian models.

  13. Inviting parents to take part in paediatric palliative care research: A mixed-methods examination of selection bias

    OpenAIRE

    Crocker, Joanna C; Beecham, Emma; Kelly, Paula; Dinsdale, Andrew P; Hemsley, June; Jones, Louise; Bluebond-Langner, Myra

    2015-01-01

    Background: Recruitment to paediatric palliative care research is challenging, with high rates of non-invitation of eligible families by clinicians. The impact on sample characteristics is unknown. Aim: To investigate, using mixed methods, non-invitation of eligible families and ensuing selection bias in an interview study about parents? experiences of advance care planning (ACP). Design: We examined differences between eligible families invited and not invited to participate by clinicians us...

  14. Possible Biases of Researchers? Attitudes Toward Video Games: Publication Trends Analysis of the Medical Literature (1980?2013)

    OpenAIRE

    Segev, Aviv; Rovner, Mitchell; Appel, David Ian; Abrams, Aaron W; Rotem, Michal; Bloch, Yuval

    2016-01-01

    Background The study of video games is expanding, and so is the debate regarding their possible positive and deleterious effects. As controversies continue, several researchers have expressed their concerns about substantial biases existing in the field, which might lead to the creation of a skewed picture, both in the professional and in the lay literature. However, no study has tried to examine this issue quantitatively. Objective The objective of our study was to examine possible systemati...

  15. Assessing bias associated with geocoding of historical residence in epidemiology research

    Directory of Open Access Journals (Sweden)

    Daikwon Han

    2013-05-01

    Full Text Available The use of geocoded historical residence as proxy for retrospective assessment of exposure in early life is increasing in epidemiological studies of chronic health outcomes. Dealing with historical residence poses challenges, primarily due to higher uncertainties associated with data collection and processing. A possible source of bias is connected with the exclusion of subjects, who cannot, for various reasons, be geocoded. We evaluated the potential bias that may arise due to incomplete geocoding, using birth residence data collected as part of a population-based case-control study of breast cancer in western New York state. We found that geocoded and non-geocoded populations did not differ in the distribution of most risk factors compared, and that the geocoding status did not modify the spatial patterns of the study populations. However, the results emphasize the need for epidemiological studies to consider the potential biases that may be introduced by geocoding of historical residence when investigating retrospectively chronic disease and early-life exposure.

  16. Thermodynamic constitutive model for load-biased thermal cycling test of shape memory alloy

    International Nuclear Information System (INIS)

    Young, Sung; Nam, Tae-Hyun

    2013-01-01

    Graphical abstract: - Highlights: • Thermodynamic calculation model for martensitic transformation of shape memory alloy was proposed. • Evolution of the self-accommodation was considered independently by a rate-dependent kinetic equation. • Finite element calculation was conducted for B2–B19′ transformation of Ti–44.5Ni–5Cu–0.5 V (at.%). • Three-dimensional numerical results predict the macroscopic strain under bias loading accurately. - Abstract: This paper presents a three-dimensional calculation model for martensitic phase transformation of shape memory alloy. Constitutive model based on thermodynamic theory was provided. The average behavior was accounted for by considering the volume fraction of each martensitic variant in the material. Evolution of the volume fraction of each variant was determined by a rate-dependent kinetic equation. We assumed that nucleation rate is faster for the self-accommodation than for the stress-induced variants. Three-dimensional finite element analysis was conducted and the results were compared with the experimental data of Ti–44.5Ni–5Cu–0.5 V (at.%) alloy under bias loading

  17. Plant Disease Severity Assessment-How Rater Bias, Assessment Method, and Experimental Design Affect Hypothesis Testing and Resource Use Efficiency.

    Science.gov (United States)

    Chiang, Kuo-Szu; Bock, Clive H; Lee, I-Hsuan; El Jarroudi, Moussa; Delfosse, Philippe

    2016-12-01

    The effect of rater bias and assessment method on hypothesis testing was studied for representative experimental designs for plant disease assessment using balanced and unbalanced data sets. Data sets with the same number of replicate estimates for each of two treatments are termed "balanced" and those with unequal numbers of replicate estimates are termed "unbalanced". The three assessment methods considered were nearest percent estimates (NPEs), an amended 10% incremental scale, and the Horsfall-Barratt (H-B) scale. Estimates of severity of Septoria leaf blotch on leaves of winter wheat were used to develop distributions for a simulation model. The experimental designs are presented here in the context of simulation experiments which consider the optimal design for the number of specimens (individual units sampled) and the number of replicate estimates per specimen for a fixed total number of observations (total sample size for the treatments being compared). The criterion used to gauge each method was the power of the hypothesis test. As expected, at a given fixed number of observations, the balanced experimental designs invariably resulted in a higher power compared with the unbalanced designs at different disease severity means, mean differences, and variances. Based on these results, with unbiased estimates using NPE, the recommended number of replicate estimates taken per specimen is 2 (from a sample of specimens of at least 30), because this conserves resources. Furthermore, for biased estimates, an apparent difference in the power of the hypothesis test was observed between assessment methods and between experimental designs. Results indicated that, regardless of experimental design or rater bias, an amended 10% incremental scale has slightly less power compared with NPEs, and that the H-B scale is more likely than the others to cause a type II error. These results suggest that choice of assessment method, optimizing sample number and number of replicate

  18. Qualitative Marketing Research Through Usability Testing

    Directory of Open Access Journals (Sweden)

    Orzan Mihai

    2008-04-01

    Full Text Available Usability is an attribute of any good product, just as its functionality. It refers mainly to the utility of a product for its indented users, as well as to its ease of use. And whilst a correct functionality is critical for the commercial success of any product, its value comes through the human needs that it fulfills, which is determined through various marketing research techniques. In parallel, the IT&C community has developed in the last two decades its own type of research, called usability testing, used mainly to evaluate interface ease of use and all usability problems associated with.software products. This article aims at finding the right place for usability testing and usability professionals in the marketing community, as well as drawing a wider picture, from a marketing research perspective, on one of the most popular topics in IT&C community for the benefit of marketing scholars and professionals.

  19. Wave Energy Research, Testing and Demonstration Center

    Energy Technology Data Exchange (ETDEWEB)

    Batten, Belinda [Oregon State Univ., Corvallis, OR (United States)

    2014-09-30

    The purpose of this project was to build upon the research, development and testing experience of the Northwest National Marine Renewable Energy Center (NNMREC) to establish a non-grid connected open-ocean testing facility for wave energy converters (WECs) off the coast of Newport, Oregon. The test facility would serve as the first facility of its kind in the continental US with a fully energetic wave resource where WEC technologies could be proven for west coast US markets. The test facility would provide the opportunity for self-contained WEC testing or WEC testing connected via an umbilical cable to a mobile ocean test berth (MOTB). The MOTB would act as a “grid surrogate” measuring energy produced by the WEC and the environmental conditions under which the energy was produced. In order to realize this vision, the ocean site would need to be identified through outreach to community stakeholders, and then regulatory and permitting processes would be undertaken. Part of those processes would require environmental baseline studies and site analysis, including benthic, acoustic and wave resource characterization. The MOTB and its myriad systems would need to be designed and constructed.The first WEC test at the facility with the MOTB was completed within this project with the WET-NZ device in summer 2012. In summer 2013, the MOTB was deployed with load cells on its mooring lines to characterize forces on mooring systems in a variety of sea states. Throughout both testing seasons, studies were done to analyze environmental effects during testing operations. Test protocols and best management practices for open ocean operations were developed. As a result of this project, the non-grid connected fully energetic WEC test facility is operational, and the MOTB system developed provides a portable concept for WEC testing. The permitting process used provides a model for other wave energy projects, especially those in the Pacific Northwest that have similar

  20. Are MFT-B Results Biased Because of Students Who Do Not Take the Test?

    Science.gov (United States)

    Valero, Magali; Kocher, Claudia

    2014-01-01

    The authors study the characteristics of students who take the Major Field Test in Business (MFT-B) versus those who do not. The authors find that students with higher cumulative grade point averages (GPAs) are more likely to take the test. Additionally, students are more likely to take the test if it is offered late in the semester. Further…

  1. Negativity bias and task motivation: testing the effectiveness of positively versus negatively framed incentives.

    Science.gov (United States)

    Goldsmith, Kelly; Dhar, Ravi

    2013-12-01

    People are frequently challenged by goals that demand effort and persistence. As a consequence, philosophers, psychologists, economists, and others have studied the factors that enhance task motivation. Using a sample of undergraduate students and a sample of working adults, we demonstrate that the manner in which an incentive is framed has implications for individuals' task motivation. In both samples we find that individuals are less motivated when an incentive is framed as a means to accrue a gain (positive framing) as compared with when the same incentive is framed as a means to avoid a loss (negative framing). Further, we provide evidence for the role of the negativity bias in this effect, and highlight specific populations for whom positive framing may be least motivating. Interestingly, we find that people's intuitions about when they will be more motivated show the opposite pattern, with people predicting that positively framed incentives will be more motivating than negatively framed incentives. We identify a lay belief in the positive correlation between enjoyment and task motivation as one possible factor contributing to the disparity between predicted and actual motivation as a result of the framing of the incentive. We conclude with a discussion of the managerial implications for these findings. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  2. Education Research: Bias and poor interrater reliability in evaluating the neurology clinical skills examination

    Science.gov (United States)

    Schuh, L A.; London, Z; Neel, R; Brock, C; Kissela, B M.; Schultz, L; Gelb, D J.

    2009-01-01

    Objective: The American Board of Psychiatry and Neurology (ABPN) has recently replaced the traditional, centralized oral examination with the locally administered Neurology Clinical Skills Examination (NEX). The ABPN postulated the experience with the NEX would be similar to the Mini-Clinical Evaluation Exercise, a reliable and valid assessment tool. The reliability and validity of the NEX has not been established. Methods: NEX encounters were videotaped at 4 neurology programs. Local faculty and ABPN examiners graded the encounters using 2 different evaluation forms: an ABPN form and one with a contracted rating scale. Some NEX encounters were purposely failed by residents. Cohen’s kappa and intraclass correlation coefficients (ICC) were calculated for local vs ABPN examiners. Results: Ninety-eight videotaped NEX encounters of 32 residents were evaluated by 20 local faculty evaluators and 18 ABPN examiners. The interrater reliability for a determination of pass vs fail for each encounter was poor (kappa 0.32; 95% confidence interval [CI] = 0.11, 0.53). ICC between local faculty and ABPN examiners for each performance rating on the ABPN NEX form was poor to moderate (ICC range 0.14-0.44), and did not improve with the contracted rating form (ICC range 0.09-0.36). ABPN examiners were more likely than local examiners to fail residents. Conclusions: There is poor interrater reliability between local faculty and American Board of Psychiatry and Neurology examiners. A bias was detected for favorable assessment locally, which is concerning for the validity of the examination. Further study is needed to assess whether training can improve interrater reliability and offset bias. GLOSSARY ABIM = American Board of Internal Medicine; ABPN = American Board of Psychiatry and Neurology; CI = confidence interval; HFH = Henry Ford Hospital; ICC = intraclass correlation coefficients; IM = internal medicine; mini-CEX = Mini-Clinical Evaluation Exercise; NEX = Neurology Clinical

  3. Persistent bias in expert judgments about free will and moral responsibility: a test of the expertise defense.

    Science.gov (United States)

    Schulz, Eric; Cokely, Edward T; Feltz, Adam

    2011-12-01

    Many philosophers appeal to intuitions to support some philosophical views. However, there is reason to be concerned about this practice as scientific evidence has documented systematic bias in philosophically relevant intuitions as a function of seemingly irrelevant features (e.g., personality). One popular defense used to insulate philosophers from these concerns holds that philosophical expertise eliminates the influence of these extraneous factors. Here, we test this assumption. We present data suggesting that verifiable philosophical expertise in the free will debate-as measured by a reliable and validated test of expert knowledge-does not eliminate the influence of one important extraneous feature (i.e., the heritable personality trait extraversion) on judgments concerning freedom and moral responsibility. These results suggest that, in at least some important cases, the expertise defense fails. Implications for the practice of philosophy, experimental philosophy, and applied ethics are discussed. Copyright © 2011 Elsevier Inc. All rights reserved.

  4. Bootstrap confidence intervals and bias correction in the estimation of HIV incidence from surveillance data with testing for recent infection.

    Science.gov (United States)

    Carnegie, Nicole Bohme

    2011-04-15

    The incidence of new infections is a key measure of the status of the HIV epidemic, but accurate measurement of incidence is often constrained by limited data. Karon et al. (Statist. Med. 2008; 27:4617–4633) developed a model to estimate the incidence of HIV infection from surveillance data with biologic testing for recent infection for newly diagnosed cases. This method has been implemented by public health departments across the United States and is behind the new national incidence estimates, which are about 40 per cent higher than previous estimates. We show that the delta method approximation given for the variance of the estimator is incomplete, leading to an inflated variance estimate. This contributes to the generation of overly conservative confidence intervals, potentially obscuring important differences between populations. We demonstrate via simulation that an innovative model-based bootstrap method using the specified model for the infection and surveillance process improves confidence interval coverage and adjusts for the bias in the point estimate. Confidence interval coverage is about 94–97 per cent after correction, compared with 96–99 per cent before. The simulated bias in the estimate of incidence ranges from −6.3 to +14.6 per cent under the original model but is consistently under 1 per cent after correction by the model-based bootstrap. In an application to data from King County, Washington in 2007 we observe correction of 7.2 per cent relative bias in the incidence estimate and a 66 per cent reduction in the width of the 95 per cent confidence interval using this method. We provide open-source software to implement the method that can also be extended for alternate models.

  5. A Call for Examining Replication and Bias in Special Education Research

    Science.gov (United States)

    Cook, Bryan G.

    2014-01-01

    Valid, scientific research is critical for ascertaining the effects of instructional techniques on learners with disabilities and for guiding effective special education practice and policy. Researchers in fields such as psychology and medicine have identified serious and widespread shortcomings in their research literatures related to replication…

  6. Observational Research on Alcohol Use and Chronic Disease Outcome: New Approaches to Counter Biases

    Directory of Open Access Journals (Sweden)

    Wenbin Liang

    2013-01-01

    Full Text Available Background. The frequently reported protective effects of moderate alcohol consumption in observational studies may be due to unadjusted bias. Aim. To examine two new approaches that account for unknown confounding factors and allow the application of intention-to-treat analysis. Method. This study used data from the 2008, 2009, and 2010 National Health Interview Surveys conducted in the United States. Unknown confounding effects were estimated through the association between parental alcohol use and health outcomes for children, because the presence of hypothetical physiological effects of alcohol can be ruled out for this association. In order to apply intention-to-treat analysis, previous alcohol use of former drinkers was obtained by using multiple imputations. Estimates with new adjustment approaches were compared with the traditional approach. Results. The traditional analytical approach; appears to be consistent with findings from previous observational studies; when two further adjustment approaches were used, the “protective” effects of moderate drinking almost disappeared. Conclusion. Use of a proxy outcome to estimate and control residual confounding effects of alcohol use and application of the intention-to-treat principle could provide a more realistic estimation of the true effects of alcohol use on health outcomes in observational epidemiological studies.

  7. Testing for biases in selection on avian reproductive traits and partitioning direct and indirect selection using quantitative genetic models.

    Science.gov (United States)

    Reed, Thomas E; Gienapp, Phillip; Visser, Marcel E

    2016-10-01

    Key life history traits such as breeding time and clutch size are frequently both heritable and under directional selection, yet many studies fail to document microevolutionary responses. One general explanation is that selection estimates are biased by the omission of correlated traits that have causal effects on fitness, but few valid tests of this exist. Here, we show, using a quantitative genetic framework and six decades of life-history data on two free-living populations of great tits Parus major, that selection estimates for egg-laying date and clutch size are relatively unbiased. Predicted responses to selection based on the Robertson-Price Identity were similar to those based on the multivariate breeder's equation (MVBE), indicating that unmeasured covarying traits were not missing from the analysis. Changing patterns of phenotypic selection on these traits (for laying date, linked to climate change) therefore reflect changing selection on breeding values, and genetic constraints appear not to limit their independent evolution. Quantitative genetic analysis of correlational data from pedigreed populations can be a valuable complement to experimental approaches to help identify whether apparent associations between traits and fitness are biased by missing traits, and to parse the roles of direct versus indirect selection across a range of environments. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  8. Inviting parents to take part in paediatric palliative care research: a mixed-methods examination of selection bias.

    Science.gov (United States)

    Crocker, Joanna C; Beecham, Emma; Kelly, Paula; Dinsdale, Andrew P; Hemsley, June; Jones, Louise; Bluebond-Langner, Myra

    2015-03-01

    Recruitment to paediatric palliative care research is challenging, with high rates of non-invitation of eligible families by clinicians. The impact on sample characteristics is unknown. To investigate, using mixed methods, non-invitation of eligible families and ensuing selection bias in an interview study about parents' experiences of advance care planning (ACP). We examined differences between eligible families invited and not invited to participate by clinicians using (1) field notes of discussions with clinicians during the invitation phase and (2) anonymised information from the service's clinical database. Families were eligible for the ACP study if their child was receiving care from a UK-based tertiary palliative care service (Group A; N = 519) or had died 6-10 months previously having received care from the service (Group B; N = 73). Rates of non-invitation to the ACP study were high. A total of 28 (5.4%) Group A families and 21 (28.8%) Group B families (p research findings. Non-invitation and selection bias should be considered, assessed and reported in palliative care studies. © The Author(s) 2014.

  9. Relational Aggression and Hostile Attribution Biases: Testing Multiple Statistical Methods and Models

    Science.gov (United States)

    Godleski, Stephanie A.; Ostrov, Jamie M.

    2010-01-01

    The present study used both categorical and dimensional approaches to test the association between relational and physical aggression and hostile intent attributions for both relational and instrumental provocation situations using the National Institute of Child Health and Human Development longitudinal Study of Early Child Care and Youth…

  10. The BioMedical Admissions Test for medical student selection: issues of fairness and bias.

    Science.gov (United States)

    Emery, Joanne L; Bell, John F; Vidal Rodeiro, Carmen L

    2011-01-01

    The BioMedical Admissions Test (BMAT) forms part of the undergraduate medical admission process at the University of Cambridge. The fairness of admissions tests is an important issue. Aims were to investigate the relationships between applicants' background variables and BMAT scores, whether they were offered a place or rejected and, for those admitted, performance on the first year course examinations. Multilevel regression models were employed with data from three combined applicant cohorts. Admission rates for different groups were investigated with and without controlling for BMAT performance. The fairness of the BMAT was investigated by determining, for those admitted, whether scores predicted examination performance equitably. Despite some differences in applicants' BMAT performance (e.g. by school type and gender), BMAT scores predicted mean examination marks equitably for all background variables considered. The probability of achieving a 1st class examination result, however, was slightly under-predicted for those admitted from schools and colleges entering relatively few applicants. Not all differences in admission rates were accounted for by BMAT performance. However, the test constitutes only one part of a compensatory admission system in which other factors, such as interview performance, are important considerations. Results are in support of the equity of the BMAT.

  11. A Nonparametric Multidimensional IRT Approach with Applications to Ability Estimation and Test Bias.

    Science.gov (United States)

    1988-04-01

    VA 22314 800 N. Quincy Street Attn: TC Arlington, VA 22217-5000 (12 Copies) Dr. Hans Crombag Dr. Stephen Dunbar University of Leyden Lindquist...CenterEducation Research Center for Measurement Boerhaavelaan 2 University of Iowa 2334 EN Leyden Iowa City, IA 52242 The NETHERLANDS Dr. James A. Earles Mr...William Montague Naval Air Station NPRDC Code 13 Pensacola, FL 32508 San Diego, CA 92152-6800 Dr. Gary Marco Ms. Kathleen Moreno Stop 31-E Navy Personnel R

  12. Corium melt researches at VESTA test facility

    Directory of Open Access Journals (Sweden)

    Hwan Yeol Kim

    2017-10-01

    Full Text Available VESTA (Verification of Ex-vessel corium STAbilization and VESTA-S (-small test facilities were constructed at the Korea Atomic Energy Research Institute in 2010 to perform various corium melt experiments. Since then, several tests have been performed for the verification of an ex-vessel core catcher design for the EU-APR1400. Ablation tests of an impinging ZrO2 melt jet on a sacrificial material were performed to investigate the ablation characteristics. ZrO2 melt in an amount of 65–70 kg was discharged onto a sacrificial material through a well-designed nozzle, after which the ablation depths were measured. Interaction tests between the metallic melt and sacrificial material were performed to investigate the interaction kinetics of the sacrificial material. Two types of melt were used: one is a metallic corium melt with Fe 46%, U 31%, Zr 16%, and Cr 7% (maximum possible content of U and Zr for C-40, and the other is a stainless steel (SUS304 melt. Metallic melt in an amount of 1.5–2.0 kg was delivered onto the sacrificial material, and the ablation depths were measured. Penetration tube failure tests were performed for an APR1400 equipped with 61 in-core instrumentation penetration nozzles and extended tubes at the reactor lower vessel. ZrO2 melt was generated in a melting crucible and delivered down into an interaction crucible where the test specimen is installed. To evaluate the tube ejection mechanism, temperature distributions of the reactor bottom head and in-core instrumentation penetration were measured by a series of thermocouples embedded along the specimen. In addition, lower vessel failure tests for the Fukushima Daiichi nuclear power plant are being performed. As a first step, the configuration of the molten core in the plant was investigated by a melting and solidification experiment. Approximately 5 kg of a mixture, whose composition in terms of weight is UO2 60%, Zr 10%, ZrO2 15%, SUS304 14%, and B4C 1%, was melted in a

  13. Off reactor testings. Technological engineering applicative research

    International Nuclear Information System (INIS)

    Doca, Cezar

    2001-01-01

    By the end of year 2000 over 400 nuclear electro-power units were operating world wide, summing up a 350,000 MW total capacity, with a total production of 2,300 TWh, representing 16% of the world's electricity production. Other 36 units, totalizing 28,000 MW, were in construction, while a manifest orientation towards nuclear power development was observed in principal Asian countries like China, India, Japan and Korea. In the same world's trend one find also Romania, the Cernavoda NPP Unit 1 generating electrical energy into the national system beginning with 2 December 1996. Recently, the commercial contract was completed for finishing the Cernavoda NPP Unit 2 and launching it into operation by the end of year 2004. An important role in developing the activity of research and technological engineering, as technical support for manufacturing the CANDU type nuclear fuel and supplying with equipment the Cernavoda units, was played by the Division 7 TAR of the INR Pitesti. Qualification testings were conducted for: - off-reactor CANDU type nuclear fuel; - FARE tools, pressure regulators, explosion proof panels; channel shutting, as well as functional testing for spare pushing facility as a first step in the frame of the qualification tests for the charging/discharging machine (MID) 4 and 5 endings. Testing facilities are described, as well as high pressure hot/cool loops, measuring chains, all of them fulfilling the requirements of quality assurance. The nuclear fuel off-reactor tests were carried out to determine: strength; endurance; impact, pressure fall and wear resistance. For Cernavoda NPP equipment testings were carried out for: the explosion proof panels, pressure regulators, behaviour to vibration and wear of the steam generation tubings, effects of vibration upon different electronic component, channel shutting (for Cernavoda Unit 2), MID operating at 300 and 500 cycles. A number of R and D programs were conducted in the frame of division 7 TAR of INR

  14. Use of differential item functioning (DIF analysis for bias analysis in test construction

    Directory of Open Access Journals (Sweden)

    Marié De Beer

    2004-10-01

    Opsomming Waar differensiële itemfunksioneringsprosedures (DIF-prosedures vir itemontleding gebaseer op itemresponsteorie (IRT tydens toetskonstruksie gebruik word, is dit moontlik om itemkarakteristiekekrommes vir dieselfde item vir verskillende subgroepe voor te stel. Hierdie krommes dui aan hoe elke item vir die verskillende subgroepe op verskillende vermoënsvlakke te funksioneer. DIF word aangetoon deur die area tussen die krommes. DIF is in die konstruksie van die 'Learning Potential Computerised Adaptive test (LPCAT' gebruik om die items te identifiseer wat sydigheid ten opsigte van geslag, kultuur, taal of opleidingspeil geopenbaar het. Items wat ’n voorafbepaalde vlak van DIF oorskry het, is uit die finale itembank weggelaat, ongeag die subgroep wat bevoordeel of benadeel is. Die proses en resultate van die DIF-ontleding word bespreek.

  15. Research-scale melter test report

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, M.F.; Elliott, M.L.; Eyler, L.L.; Freeman, C.J.; Higginson, J.J.; Mahoney, L.A.; Powell, M.R.

    1994-05-01

    The Melter Performance Assessment (MPA) activity in the Pacific Northwest Laboratory`s (PNL) Hanford Waste Vitrification Plant (HWVP) Technology Development (PHTD) effort is intended to determine the impact of noble metals on the operational life of the reference HWVP melter. As a part of this activity, a parametric melter test was completed using a Research-Scale Melter (RSM). The RSM is a small, approximately 1/100-scale melter, 6-in.-diameter, that allows rapid changing of process conditions and subsequent re-establishment of a steady-state condition. The test matrix contained nine different segments that varied the melter operating parameters (glass and plenum temperatures) and feed properties (oxide concentration, redox potential, and noble metal concentrations) so that the effects of these parameters on noble metal agglomeration on the melter floor could be evaluated. The RSM operated for 48 days and consumed 1,300 L of feed, equating to 153 tank turnovers. The run produced 531 kg of glass. During the latter portion of the run, the resistance between the electrodes decreased. Upon destructive examination of the melter, a layer of noble metals was found on the bottom. This was surprising because the glass residence time in the RSM is only 10% of the HWVP plant melter. The noble metals layer impacted the melter significantly. Approximately 1/3 of one paddle electrode was melted or corroded off. The cause is assumed to be localized heating from short circuiting of the electrode to the noble metal layer. The metal layer also removed approximately 1/2 in. of the refractory on the bottom of the melter. The mechanism for this damage is not presently known.

  16. Research-scale melter test report

    International Nuclear Information System (INIS)

    Cooper, M.F.; Elliott, M.L.; Eyler, L.L.; Freeman, C.J.; Higginson, J.J.; Mahoney, L.A.; Powell, M.R.

    1994-05-01

    The Melter Performance Assessment (MPA) activity in the Pacific Northwest Laboratory's (PNL) Hanford Waste Vitrification Plant (HWVP) Technology Development (PHTD) effort is intended to determine the impact of noble metals on the operational life of the reference HWVP melter. As a part of this activity, a parametric melter test was completed using a Research-Scale Melter (RSM). The RSM is a small, approximately 1/100-scale melter, 6-in.-diameter, that allows rapid changing of process conditions and subsequent re-establishment of a steady-state condition. The test matrix contained nine different segments that varied the melter operating parameters (glass and plenum temperatures) and feed properties (oxide concentration, redox potential, and noble metal concentrations) so that the effects of these parameters on noble metal agglomeration on the melter floor could be evaluated. The RSM operated for 48 days and consumed 1,300 L of feed, equating to 153 tank turnovers. The run produced 531 kg of glass. During the latter portion of the run, the resistance between the electrodes decreased. Upon destructive examination of the melter, a layer of noble metals was found on the bottom. This was surprising because the glass residence time in the RSM is only 10% of the HWVP plant melter. The noble metals layer impacted the melter significantly. Approximately 1/3 of one paddle electrode was melted or corroded off. The cause is assumed to be localized heating from short circuiting of the electrode to the noble metal layer. The metal layer also removed approximately 1/2 in. of the refractory on the bottom of the melter. The mechanism for this damage is not presently known

  17. Challenging Perceptions of Academic Research as Bias Free: Promoting a Social Justice Framework in Social Work Research Methods Courses

    Science.gov (United States)

    Nicotera, Nicole; Walls, N. Eugene

    2010-01-01

    The required research courses in social work education are, perhaps, one of the more difficult content areas in which to infuse direct teaching and knowledge acquisition of multiculturalism. The study presented in this article examines the outcomes of systematically addressing social justice within a required master's level social work research…

  18. Testing the effectiveness of certainty scales, cheap talk, and dissonance-minimization in reducing hypothetical bias in contingent valuation studies

    Science.gov (United States)

    Mark Morrison; Thomas C. Brown

    2009-01-01

    Stated preference methods such as contingent valuation and choice modeling are subject to various biases that may lead to differences between actual and hypothetical willingness to pay. Cheap talk, follow-up certainty scales, and dissonance minimization are three techniques for reducing this hypothetical bias. Cheap talk and certainty scales have received considerable...

  19. Fenestration System Performance Research, Testing, and Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Jim Benney

    2009-11-30

    The US DOE was and is instrumental to NFRC's beginning and its continued success. The 2005 to 2009 funding enables NFRC to continue expanding and create new, improved ratings procedures. Research funded by the US DOE enables increased fenestration energy rating accuracy. International harmonization efforts supported by the US DOE allow the US to be the global leader in fenestration energy ratings. Many other governments are working with the NFRC to share its experience and knowledge toward development of their own national fenestration rating process similar to the NFRC's. The broad and diverse membership composition of NFRC allows anyone with a fenestration interest to come forward with an idea or improvement to the entire fenestration community for consideration. The NFRC looks forward to the next several years of growth while remaining the nation's resource for fair, accurate, and credible fenestration product energy ratings. NFRC continues to improve its rating system by considering new research, methodologies, and expanding to include new fenestration products. Currently, NFRC is working towards attachment energy ratings. Attachments are blinds, shades, awnings, and overhangs. Attachments may enable a building to achieve significant energy savings. An NFRC rating will enable fair competition, a basis for code references, and a new ENERGY STAR product category. NFRC also is developing rating methods to consider non specular glazing such as fritted glass. Commercial applications frequently use fritted glazing, but no rating method exists. NFRC is testing new software that may enable this new rating and contribute further to energy conservation. Around the world, many nations are seeking new energy conservation methods and NFRC is poised to harmonize its rating system assisting these nations to better manage and conserve energy in buildings by using NFRC rated and labeled fenestration products. As this report has shown, much more work needs to be

  20. Biased and inadequate citation of prior research in reports of cardiovascular trials is a continuing source of waste in research.

    Science.gov (United States)

    Sawin, Veronica I; Robinson, Karen A

    2016-01-01

    We assessed citation of prior research over time and the association of citation with the agreement of results between the trial being reported and the prior trial. Groups of pharmacologic trials in cardiovascular disease were created using meta-analyses, and we assessed citation within these groups. We calculated the proportion of prior trials cited, the proportion of study participants captured in citations, and agreement of results between citing and cited trials. Analysis included 86 meta-analyses with 580 trials published between 1982 and 2011. Reports of trials cited 25% (median; 95% confidence interval [CI], 23-27%) of prior trials, capturing 31% (95% CI, 25-36%) of trial participants. Neither measure differed by publication of the citing trial before vs. after 2005. Prior trials with results that agreed with the reports of trials (supportive trials) were significantly more likely to be cited than nonsupportive trials (relative risk 1.45; 95% CI, 1.30-1.61, P < 0.001). Selective undercitation of prior research continues; three quarters of existing evidence is ignored. This source of waste may result in unnecessary, unethical, and unscientific studies. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Congenital bladder exstrophy associated with Duogynon hormonal pregnancy tests-signal for teratogenicity or consumer report bias?

    Science.gov (United States)

    Tümmler, Gregor; Rißmann, Anke; Meister, Reinhard; Schaefer, Christof

    2014-06-01

    A combination of ethinylestradiol and 10mg norethisterone under the brand names of Duogynon (Germany) or Primodos (UK) was used as a pregnancy test until the 1970s. Until very recently there was continuing public concern about the safety of these drugs and legal proceedings were instituted against the medicinal authorization holder. Given the lack of epidemiological studies focusing on Duogynon/Primodos, the present study evaluates 296 consumer reports of the German Duogynon database and compares the reported birth defects with data from a population based birth registry. The most striking result is an increase of bladder exstrophy (OR=37.27; 95%-CI 14.56-95.28). Neural tube defects (OR=2.99; 95%-CI 1.85-4.84) and renal agenesis (OR=2.53; 95%-CI 1.17-5.45) were also significantly increased. Bladder exstrophy may be a yet undetected teratogenic effect of Duogynon, but may also represent a reporting bias. The present study highlights the difficulties of evaluating consumer reports which may be influenced by public media. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. The history of research on the filled pause as evidence of the written language bias in linguistics (Linell, 1982).

    Science.gov (United States)

    O'Connell, Daniel C; Kowal, Sabine

    2004-11-01

    Erard's (2004) publication in the New York Times of a journalistic history of the filled pause serves as the occasion for this critical review of the past half-century of research on the filled pause. Historically, the various phonetic realizations or instantiations of the filled pause have been presented with an odd recurrent admixture of the interjection ah. In addition, the filled pause has been consistently associated with both hesitation and disfluency. The present authors hold that such a mandatory association of the filled pause with disfluency is the product of The written language bias in linguistics [Linell, 1982] and disregards much cogent evidence to the contrary. The implicit prescriptivism of well formedness--a demand derived from literacy--must be rejected; literate well formedness is not a necessary or even typical property of spontaneous spoken discourse; its structures and functions--including those of the filled pause--are very different from those of written language The recent work of Clark and Fox Tree (2002) holds promise for moving the status of the filled pause not only toward that of a conventional word, but also toward its status as an interjection. This latter development is also being fostered by lexicographers. Nonetheless, in view of ongoing research regarding the disparate privileges of occurrence and functions of filled pauses in comparison with interjections, the present authors are reluctant to categorize the filled pause as an interjection.

  3. bcROCsurface: an R package for correcting verification bias in estimation of the ROC surface and its volume for continuous diagnostic tests.

    Science.gov (United States)

    To Duc, Khanh

    2017-11-18

    Receiver operating characteristic (ROC) surface analysis is usually employed to assess the accuracy of a medical diagnostic test when there are three ordered disease status (e.g. non-diseased, intermediate, diseased). In practice, verification bias can occur due to missingness of the true disease status and can lead to a distorted conclusion on diagnostic accuracy. In such situations, bias-corrected inference tools are required. This paper introduce an R package, named bcROCsurface, which provides utility functions for verification bias-corrected ROC surface analysis. The shiny web application of the correction for verification bias in estimation of the ROC surface analysis is also developed. bcROCsurface may become an important tool for the statistical evaluation of three-class diagnostic markers in presence of verification bias. The R package, readme and example data are available on CRAN. The web interface enables users less familiar with R to evaluate the accuracy of diagnostic tests, and can be found at http://khanhtoduc.shinyapps.io/bcROCsurface_shiny/ .

  4. Engineer Research and Development Center's Materials Testing Center (MTC)

    Data.gov (United States)

    Federal Laboratory Consortium — The Engineer Research and Development Center's Materials Testing Center (MTC) is committed to quality testing and inspection services that are delivered on time and...

  5. Sampler bias -- Phase 1

    International Nuclear Information System (INIS)

    Blanchard, R.J.

    1995-01-01

    This documents Phase 1 determinations on sampler induced bias for four sampler types used in tank characterization. Each sampler, grab sampler or bottle-on-a-string, auger sampler, sludge sampler and universal sampler, is briefly discussed and their physical limits noted. Phase 2 of this document will define additional testing and analysis to further define Sampler Bias

  6. Practical Considerations about Expected A Posteriori Estimation in Adaptive Testing: Adaptive A Priori, Adaptive Correction for Bias, and Adaptive Integration Interval.

    Science.gov (United States)

    Raiche, Gilles; Blais, Jean-Guy

    In a computerized adaptive test (CAT), it would be desirable to obtain an acceptable precision of the proficiency level estimate using an optimal number of items. Decreasing the number of items is accompanied, however, by a certain degree of bias when the true proficiency level differs significantly from the a priori estimate. G. Raiche (2000) has…

  7. The Response Shift Bias in Self-Report Tests: A Function of an Expectation of Change or a Shift in Internal Scaling?

    Science.gov (United States)

    Riedel, Sharon; And Others

    Self-report, pre/post testing is a frequently employed measure of therapeutic change. To investigate whether expectation of change might be an alternative explanation to the scale shift explanation of response shift bias in a self-report measure, a two-session assertiveness training intervention for college women was evaluated under manipulated…

  8. Current Research/Development in Language Testing.

    Science.gov (United States)

    Oller, John W., Jr.

    A discussion of language testing looks at the relationship between the processes of language learning and language testing, particularly from the point of view of pragmatics theory. It outlines some of the theory of Charles Sanders Pierce and its role in the evolution of linguistic theory, as well as the work of other theorists concerning the…

  9. Equipment qualification testing methodology research at Sandia Laboratories

    International Nuclear Information System (INIS)

    Jeppesen, D.

    1983-01-01

    The Equipment Qualification Research Testing (EQRT) program is an evolutionary outgrowth of the Qualification Testing Evaluation (QTE) program at Sandia. The primary emphasis of the program has been qualification methodology research. The EQRT program offers to the industry a research-oriented perspective on qualification-related component performance, as well as refinements to component testing standards which are based upon actual component testing research

  10. On a New Variance Reduction Technique: Neural Network Biasing-a Study of Two Test Cases with the Monte Carlo Code Tripoli4

    International Nuclear Information System (INIS)

    Dumonteil, E.

    2009-01-01

    Various variance-reduction techniques are used in Monte Carlo particle transport. Most of them rely either on a hypothesis made by the user (parameters of the exponential biasing, mesh and weight bounds for weight windows, etc.) or on a previous calculation of the system with, for example, a deterministic solver. This paper deals with a new acceleration technique, namely, auto-adaptative neural network biasing. Indeed, instead of using any a priori knowledge of the system, it is possible, at a given point in a simulation, to use the Monte Carlo histories previously simulated to train a neural network, which, in return, should be able to provide an estimation of the adjoint flux, used then for biasing the simulation. We will describe this method, detail its implementation in the Monte Carlo code Tripoli4, and discuss its results on two test cases. (author)

  11. The WIPP research and development test program

    International Nuclear Information System (INIS)

    Tyler, L.D.

    1985-01-01

    The WIPP (Waste Isolation Pilot Plant) is a DOE RandD Facility for the purpose of developing the technology needed for the safe disposal of the United States defense-related radioactive waste. The in-situ test program is defined for the thermal-structural interactions, plugging and sealing, and waste package interactions in a salt environment. An integrated series of large-scale underground tests address the issues of both systems and long-term isolation performance of a repository

  12. Progeria Research Foundation Diagnostic Testing Program

    Science.gov (United States)

    ... Share the DVD Meet the Kids in the Movie Bring LATS to the classroom! Close News/Events ... this could severely affect their research results and interpretation. Through the PRF Diagnostics Program, each cell line ...

  13. Sympathetic bias.

    Science.gov (United States)

    Levy, David M; Peart, Sandra J

    2008-06-01

    We wish to deal with investigator bias in a statistical context. We sketch how a textbook solution to the problem of "outliers" which avoids one sort of investigator bias, creates the temptation for another sort. We write down a model of the approbation seeking statistician who is tempted by sympathy for client to violate the disciplinary standards. We give a simple account of one context in which we might expect investigator bias to flourish. Finally, we offer tentative suggestions to deal with the problem of investigator bias which follow from our account. As we have given a very sparse and stylized account of investigator bias, we ask what might be done to overcome this limitation.

  14. Implicit Racial Biases in Preschool Children and Adults from Asia and Africa

    Science.gov (United States)

    Qian, Miao K.; Heyman, Gail D.; Quinn, Paul C.; Messi, Francoise A.; Fu, Genyue; Lee, Kang

    2016-01-01

    This research used an Implicit Racial Bias Test to investigate implicit racial biases among 3- to 5-year-olds and adult participants in China (N = 213) and Cameroon (N = 257). In both cultures, participants displayed high levels of racial biases that remained stable between 3 and 5 years of age. Unlike adults, young children's implicit racial…

  15. The Development of Spatial Frequency Biases in Face Recognition

    Science.gov (United States)

    Leonard, Hayley C.; Karmiloff-Smith, Annette; Johnson, Mark H.

    2010-01-01

    Previous research has suggested that a mid-band of spatial frequencies is critical to face recognition in adults, but few studies have explored the development of this bias in children. We present a paradigm adapted from the adult literature to test spatial frequency biases throughout development. Faces were presented on a screen with particular…

  16. Leak testing requirements at a research facility

    International Nuclear Information System (INIS)

    Conner, J.B.

    1979-01-01

    Since September, 1952, Lawrence Livermore Laboratory has conducted pioneering research in applied science. A vital part of this activity has been the development of a variety of high vacuum and ultrahigh vacuum systems. Leaks occur in everything, including vacuum systems. The mass spectrometer leak detection equipment is described

  17. A test of genetic association among male nuptial coloration, female mating preference, and male aggression bias within a polymorphic population of cichlid fish

    Directory of Open Access Journals (Sweden)

    Inke van der SLUIJS, Peter D. DIJKSTRA, Charlotte M. LINDEYER et al.

    2013-04-01

    Full Text Available Both inter- and intrasexual selection have been implicated in the origin and maintenance of species-rich taxa with diverse sexual traits. Simultaneous disruptive selection by female mate choice and male-male competition can, in theory, lead to speciation without geographical isolation if both act on the same male trait. Female mate choice can generate discontinuities in gene flow, while male-male competition can generate negative frequency-dependent selection stabilizing the male trait polymorphism. Speciation may be facilitated when mating preference and/or aggression bias are physically linked to the trait they operate on. We tested for genetic associations among female mating preference, male aggression bias and male coloration in the Lake Victoria cichlid Pundamilia. We crossed females from a phenotypically variable population with males from both extreme ends of the phenotype distribution in the same population (blue or red. Male offspring of a red sire were significantly redder than males of a blue sire, indicating that intra-population variation in male coloration is heritable. We tested mating preferences of female offspring and aggression biases of male offspring using binary choice tests. There was no evidence for associations at the family level between female mating preferences and coloration of sires, but dam identity had a significant effect on female mate preference. Sons of the red sire directed significantly more aggression to red than blue males, whereas sons of the blue sire did not show any bias. There was a positive correlation among individuals between male aggression bias and body coloration, possibly due to pleiotropy or physical linkage, which could facilitate the maintenance of color polymorphism [Current Zoology 59 (2: 221-229, 2013].

  18. Survey Response-Related Biases in Contingent Valuation: Concepts, Remedies, and Empirical Application to Valuing Aquatic Plant Management

    Science.gov (United States)

    Mark L. Messonnier; John C. Bergstrom; Chrisopher M. Cornwell; R. Jeff Teasley; H. Ken Cordell

    2000-01-01

    Simple nonresponse and selection biases that may occur in survey research such as contingent valuation applications are discussed and tested. Correction mechanisms for these types of biases are demonstrated. Results indicate the importance of testing and correcting for unit and item nonresponse bias in contingent valuation survey data. When sample nonresponse and...

  19. An Attitudinal Explanation of Biases in the Criminal Justice System: An Empirical Testing of Defensive Attribution Theory

    Science.gov (United States)

    Herzog, Sergio

    2008-01-01

    Theoretical perspectives, supported by empirical evidence, have consistently argued that the judicial treatment of offenders by criminal justice agents is sometimes biased by extralegal factors, such as offenders' sociodemographic characteristics. According to defensive attribution theory, individuals tend to protect themselves against unfortunate…

  20. A Question of Control? Examining the Role of Control Conditions in Experimental Psychopathology using the Example of Cognitive Bias Modification Research.

    Science.gov (United States)

    Blackwell, Simon E; Woud, Marcella L; MacLeod, Colin

    2017-10-26

    While control conditions are vitally important in research, selecting the optimal control condition can be challenging. Problems are likely to arise when the choice of control condition is not tightly guided by the specific question that a given study aims to address. Such problems have become increasingly apparent in experimental psychopathology research investigating the experimental modification of cognitive biases, particularly as the focus of this research has shifted from theoretical questions concerning mechanistic aspects of the association between cognitive bias and emotional vulnerability, to questions that instead concern the clinical efficacy of 'cognitive bias modification' (CBM) procedures. We discuss the kinds of control conditions that have typically been employed in CBM research, illustrating how difficulties can arise when changes in the types of research questions asked are not accompanied by changes in the control conditions employed. Crucially, claims made on the basis of comparing active and control conditions within CBM studies should be restricted to those conclusions allowed by the specific control condition employed. CBM studies aiming to establish clinical utility are likely to require quite different control conditions from CBM studies aiming to illuminate mechanisms. Further, conclusions concerning the clinical utility of CBM interventions cannot necessarily be drawn from studies in which the control condition has been chosen to answer questions concerning mechanisms. Appreciating the need to appropriately alter control conditions in the transition from basic mechanisms-focussed investigations to applied clinical research could greatly facilitate the translational process.

  1. Aerodynamic research of a racing car based on wind tunnel test and computational fluid dynamics

    Directory of Open Access Journals (Sweden)

    Wang Jianfeng

    2018-01-01

    Full Text Available Wind tunnel test and computational fluid dynamics (CFD simulation are two main methods for the study of automotive aerodynamics. CFD simulation software solves the results in calculation by using the basic theory of aerodynamic. Calculation will inevitably lead to bias, and the wind tunnel test can effectively simulate the real driving condition, which is the most effective aerodynamics research method. This paper researches the aerodynamic characteristics of the wing of a racing car. Aerodynamic model of a racing car is established. Wind tunnel test is carried out and compared with the simulation results of computational fluid dynamics. The deviation of the two methods is small, and the accuracy of computational fluid dynamics simulation is verified. By means of CFD software simulation, the coefficients of six aerodynamic forces are fitted and the aerodynamic equations are obtained. Finally, the aerodynamic forces and torques of the racing car travel in bend are calculated.

  2. 10 CFR 1021.212 - Research, development, demonstration, and testing.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Research, development, demonstration, and testing. 1021... ACT IMPLEMENTING PROCEDURES DOE Decisionmaking § 1021.212 Research, development, demonstration, and testing. (a) This section applies to the adoption and application of programs that involve research...

  3. Research and Test Reactor Fuel Elements (RTRFE)

    International Nuclear Information System (INIS)

    Pace, Brett W.; Marinak, Edward A.

    1999-01-01

    BWX Technologies Inc. (BWXT) has experienced several production improvements over the past year. The homogeneity yields in 4.8 gU/cc U 3 Si 2 plates have increased over last year's already high yields. Through teamwork and innovative manufacturing techniques, maintaining high quality surface finishes on plates and elements is becoming easier and less expensive. Currently, BWXT is designing a fabrication development plan to reach a fuel loading of 9 gU/cc within 2 - 4 years. This development will involve a step approach requested by ANL to produce plates using U-8Mo at a loading of 6 gU/cc first and qualify the fuel at those levels. In achieving the goal of a very high-density fuel loading of 9 gU/cc, BWXT is considering employing several new, state of the art, ultrasonic testing techniques for fuel core evaluation. (author)

  4. Development and testing of new upper-limb prosthetic devices: research designs for usability testing.

    Science.gov (United States)

    Resnik, Linda

    2011-01-01

    The purposes of this article are to describe usability testing and introduce designs and methods of usability testing research as it relates to upper-limb prosthetics. This article defines usability, describes usability research, discusses research approaches to and designs for usability testing, and highlights a variety of methodological considerations, including sampling, sample size requirements, and usability metrics. Usability testing is compared with other types of study designs used in prosthetic research.

  5. A test of the critical assumption of the sensory bias model for the evolution of female mating preference using neural networks.

    Science.gov (United States)

    Fuller, Rebecca C

    2009-07-01

    The sensory bias model for the evolution of mating preferences states that mating preferences evolve as correlated responses to selection on nonmating behaviors sharing a common sensory system. The critical assumption is that pleiotropy creates genetic correlations that affect the response to selection. I simulated selection on populations of neural networks to test this. First, I selected for various combinations of foraging and mating preferences. Sensory bias predicts that populations with preferences for like-colored objects (red food and red mates) should evolve more readily than preferences for differently colored objects (red food and blue mates). Here, I found no evidence for sensory bias. The responses to selection on foraging and mating preferences were independent of one another. Second, I selected on foraging preferences alone and asked whether there were correlated responses for increased mating preferences for like-colored mates. Here, I found modest evidence for sensory bias. Selection for a particular foraging preference resulted in increased mating preference for similarly colored mates. However, the correlated responses were small and inconsistent. Selection on foraging preferences alone may affect initial levels of mating preferences, but these correlations did not constrain the joint evolution of foraging and mating preferences in these simulations.

  6. Small UAS Test Area at NASA's Dryden Flight Research Center

    Science.gov (United States)

    Bauer, Jeffrey T.

    2008-01-01

    This viewgraph presentation reviews the areas that Dryden Flight Research Center has set up for testing small Unmanned Aerial Systems (UAS). It also reviews the requirements and process to use an area for UAS test.

  7. Computers in Language Testing: Present Research and Some Future Directions.

    Science.gov (United States)

    Brown, James Dean

    1997-01-01

    Explores recent developments in the use of computers in language testing in four areas: (1) item banking; (2) computer-assisted language testing; (3) computerized-adaptive language testing; and (4) research on the effectiveness of computers in language testing. Examines educational measurement literature in an attempt to forecast the directions…

  8. Hydrogen Infrastructure Testing and Research Facility Video (Text Version)

    Science.gov (United States)

    grid integration, continuous code improvement, fuel cell vehicle operation, and renewable hydrogen Systems Integration Facility or ESIF. Research projects including H2FIRST, component testing, hydrogen

  9. An examination of gender bias on the eighth-grade MEAP science test as it relates to the Hunter Gatherer Theory of Spatial Sex Differences

    Science.gov (United States)

    Armstrong-Hall, Judy Gail

    The purpose of this study was to apply the Hunter-Gatherer Theory of sex spatial skills to responses to individual questions by eighth grade students on the Science component of the Michigan Educational Assessment Program (MEAP) to determine if sex bias was inherent in the test. The Hunter-Gatherer Theory on Spatial Sex Differences, an original theory, that suggested a spatial dimorphism concept with female spatial skill of pattern recall of unconnected items and male spatial skills requiring mental movement. This is the first attempt to apply the Hunter-Gatherer Theory on Spatial Sex Differences to a standardized test. An overall hypothesis suggested that the Hunter-Gatherer Theory of Spatial Sex Differences could predict that males would perform better on problems involving mental movement and females would do better on problems involving the pattern recall of unconnected items. Responses to questions on the 1994-95 MEAP requiring the use of male spatial skills and female spatial skills were analyzed for 5,155 eighth grade students. A panel composed of five educators and a theory developer determined which test items involved the use of male and female spatial skills. A MANOVA, using a random sample of 20% of the 5,155 students to compare male and female correct scores, was statistically significant, with males having higher scores on male spatial skills items and females having higher scores on female spatial skills items. Pearson product moment correlation analyses produced a positive correlation for both male and female performance on both types of spatial skills. The Hunter-Gatherer Theory of Spatial Sex Differences appears to be able to predict that males could perform better on the problems involving mental movement and females could perform better on problems involving the pattern recall of unconnected items. Recommendations for further research included: examination of male/female spatial skill differences at early elementary and high school levels to

  10. The construct equivalence and item bias of the pib/SpEEx conceptualisation-ability test for members of five language groups in South Africa

    Directory of Open Access Journals (Sweden)

    Pieter Schaap

    2008-11-01

    Full Text Available This study’s objective was to determine whether the Potential Index Batteries/Situation Specific Evaluation Expert (PIB/SpEEx conceptualisation (100 ability test displays construct equivalence and item bias for members of five selected language groups in South Africa. The sample consisted of a non-probability convenience sample (N = 6 261 of members of five language groups (speakers of Afrikaans, English, North Sotho, Setswana and isiZulu working in the medical and beverage industries or studying at higher-educational institutions. Exploratory factor analysis with target rotations confrmed the PIB/SpEEx 100’s construct equivalence for the respondents from these five language groups. No evidence of either uniform or non-uniform item bias of practical signifcance was found for the sample.

  11. Conceptualizing Essay Tests' Reliability and Validity: From Research to Theory

    Science.gov (United States)

    Badjadi, Nour El Imane

    2013-01-01

    The current paper on writing assessment surveys the literature on the reliability and validity of essay tests. The paper aims to examine the two concepts in relationship with essay testing as well as to provide a snapshot of the current understandings of the reliability and validity of essay tests as drawn in recent research studies. Bearing in…

  12. Journal bias or author bias?

    Science.gov (United States)

    Harris, Ian

    2016-01-01

    I read with interest the comment by Mark Wilson in the Indian Journal of Medical Ethics regarding bias and conflicts of interest in medical journals. Wilson targets one journal (the New England Journal of Medicine: NEJM) and one particular "scandal" to make his point that journals' decisions on publication are biased by commercial conflicts of interest (CoIs). It is interesting that he chooses the NEJM which, by his own admission, had one of the strictest CoI policies and had published widely on this topic. The feeling is that if the NEJM can be guilty, they can all be guilty.

  13. Altering attentional control settings causes persistent biases of visual attention.

    Science.gov (United States)

    Knight, Helen C; Smith, Daniel T; Knight, David C; Ellison, Amanda

    2016-01-01

    Attentional control settings have an important role in guiding visual behaviour. Previous work within cognitive psychology has found that the deployment of general attentional control settings can be modulated by training. However, research has not yet established whether long-term modifications of one particular type of attentional control setting can be induced. To address this, we investigated persistent alterations to feature search mode, also known as an attentional bias, towards an arbitrary stimulus in healthy participants. Subjects were biased towards the colour green by an information sheet. Attentional bias was assessed using a change detection task. After an interval of either 1 or 2 weeks, participants were then retested on the same change detection task, tested on a different change detection task where colour was irrelevant, or were biased towards an alternative colour. One experiment included trials in which the distractor stimuli (but never the target stimuli) were green. The key finding was that green stimuli in the second task attracted attention, despite this impairing task performance. Furthermore, inducing a second attentional bias did not override the initial bias toward green objects. The attentional bias also persisted for at least two weeks. It is argued that this persistent attentional bias is mediated by a chronic change to participants' attentional control settings, which is aided by long-term representations involving contextual cueing. We speculate that similar changes to attentional control settings and continuous cueing may relate to attentional biases observed in psychopathologies. Targeting these biases may be a productive approach to treatment.

  14. Are Health State Valuations from the General Public Biased? A Test of Health State Reference Dependency Using Self-assessed Health and an Efficient Discrete Choice Experiment.

    Science.gov (United States)

    Jonker, Marcel F; Attema, Arthur E; Donkers, Bas; Stolk, Elly A; Versteegh, Matthijs M

    2017-12-01

    Health state valuations of patients and non-patients are not the same, whereas health state values obtained from general population samples are a weighted average of both. The latter constitutes an often-overlooked source of bias. This study investigates the resulting bias and tests for the impact of reference dependency on health state valuations using an efficient discrete choice experiment administered to a Dutch nationally representative sample of 788 respondents. A Bayesian discrete choice experiment design consisting of eight sets of 24 (matched pairwise) choice tasks was developed, with each set providing full identification of the included parameters. Mixed logit models were used to estimate health state preferences with respondents' own health included as an additional predictor. Our results indicate that respondents with impaired health worse than or equal to the health state levels under evaluation have approximately 30% smaller health state decrements. This confirms that reference dependency can be observed in general population samples and affirms the relevance of prospect theory in health state valuations. At the same time, the limited number of respondents with severe health impairments does not appear to bias social tariffs as obtained from general population samples. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  15. Threat bias, not negativity bias, underpins differences in political ideology.

    Science.gov (United States)

    Lilienfeld, Scott O; Latzman, Robert D

    2014-06-01

    Although disparities in political ideology are rooted partly in dispositional differences, Hibbing et al.'s analysis paints with an overly broad brush. Research on the personality correlates of liberal-conservative differences points not to global differences in negativity bias, but to differences in threat bias, probably emanating from differences in fearfulness. This distinction bears implications for etiological research and persuasion efforts.

  16. White and Black American Children’s Implicit Intergroup Bias

    Science.gov (United States)

    Newheiser, Anna-Kaisa; Olson, Kristina R.

    2011-01-01

    Despite a decline in explicit prejudice, adults and children from majority groups (e.g., White Americans) often express bias implicitly, as assessed by the Implicit Association Test. In contrast, minority-group (e.g., Black American) adults on average show no bias on the IAT. In the present research, representing the first empirical investigation of whether Black children’s IAT responses parallel those of Black adults, we examined implicit bias in 7–11-year-old White and Black American children. Replicating previous findings with adults, whereas White children showed a robust ingroup bias, Black children showed no bias. Additionally, we investigated the role of valuing status in the development of implicit bias. For Black children, explicit preference for high status predicted implicit outgroup bias: Black children who explicitly expressed high preference for rich (vs. poor) people showed an implicit preference for Whites comparable in magnitude to White children’s ingroup bias. Implications for research on intergroup bias are discussed. PMID:22184478

  17. Ironic effects of racial bias during interracial interactions.

    Science.gov (United States)

    Shelton, J Nicole; Richeson, Jennifer A; Salvatore, Jessica; Trawalter, Sophie

    2005-05-01

    Previous research has suggested that Blacks like White interaction partners who make an effort to appear unbiased more than those who do not. We tested the hypothesis that, ironically, Blacks perceive White interaction partners who are more racially biased more positively than less biased White partners, primarily because the former group must make more of an effort to control racial bias than the latter. White participants in this study completed the Implicit Association Test (IAT) as a measure of racial bias and then discussed race relations with either a White or a Black partner. Whites' IAT scores predicted how positively they were perceived by Black (but not White) interaction partners, and this relationship was mediated by Blacks' perceptions of how engaged the White participants were during the interaction. We discuss implications of the finding that Blacks may, ironically, prefer to interact with highly racially biased Whites, at least in short interactions.

  18. Biased Supervision

    OpenAIRE

    Josse Delfgaauw; Michiel Souverijn

    2014-01-01

    markdownabstract__Abstract__ When verifiable performance measures are imperfect, organizations often resort to subjective performance pay. This may give supervisors the power to direct employees towards tasks that mainly benefit the supervisor rather than the organization. We cast a principal-supervisor-agent model in a multitask setting, where the supervisor has an intrinsic preference towards specific tasks. We show that subjective performance pay based on evaluation by a biased supervisor ...

  19. The picture test of separation and individuation - preliminary research

    Directory of Open Access Journals (Sweden)

    Gregor Žvelc

    2000-06-01

    Full Text Available Authors introduce a new instrument, which they developed for measuring separation and individuation process and attachment in adolescence and adulthood. The Picture Test of Separation and Individuation (PTSI is a semi–projective test. It consists of various pictures, which represent relationships with significant others. PTSI is divided into three subtests: Relationship with Mother, Relationship with Father and Attachment. In a preliminary research on a sample of college and university students authors studied basic properties of the test. The results of the research indicate that PTSI is consistent with theoretical background, has good sensitivity and is economical. The Picture Test of Separation and Individuation enables quick but complex insight into individual's relationships with significant others as well as into his/her stage of separation and individuation process. Considering satisfying results of pilot study, authors suggest further research for validation of the test.

  20. The coalitional value theory of antigay bias

    NARCIS (Netherlands)

    Winegard, Bo; Reynolds, Tania; Baumeister, Roy F.; Plant, E. Ashby

    2016-01-01

    Research indicates that antigay bias follows a specific pattern (and probably has throughout written history, at least in the West): (a) men evince more antigay bias than women; (b) men who belong to traditionally male coalitions evince more antigay bias than those who do not; (c) antigay bias is

  1. Caveats for using statistical significance tests in research assessments

    DEFF Research Database (Denmark)

    Schneider, Jesper Wiborg

    2013-01-01

    controversial and numerous criticisms have been leveled against their use. Based on examples from articles by proponents of the use statistical significance tests in research assessments, we address some of the numerous problems with such tests. The issues specifically discussed are the ritual practice......This article raises concerns about the advantages of using statistical significance tests in research assessments as has recently been suggested in the debate about proper normalization procedures for citation indicators by Opthof and Leydesdorff (2010). Statistical significance tests are highly...... argue that applying statistical significance tests and mechanically adhering to their results are highly problematic and detrimental to critical thinking. We claim that the use of such tests do not provide any advantages in relation to deciding whether differences between citation indicators...

  2. Worldwide Research, Worldwide Participation: Web-Based Test Logger

    Science.gov (United States)

    Clark, David A.

    1998-01-01

    Thanks to the World Wide Web, a new paradigm has been born. ESCORT (steady state data system) facilities can now be configured to use a Web-based test logger, enabling worldwide participation in tests. NASA Lewis Research Center's new Web-based test logger for ESCORT automatically writes selected test and facility parameters to a browser and allows researchers to insert comments. All data can be viewed in real time via Internet connections, so anyone with a Web browser and the correct URL (universal resource locator, or Web address) can interactively participate. As the test proceeds and ESCORT data are taken, Web browsers connected to the logger are updated automatically. The use of this logger has demonstrated several benefits. First, researchers are free from manual data entry and are able to focus more on the tests. Second, research logs can be printed in report format immediately after (or during) a test. And finally, all test information is readily available to an international public.

  3. Reduced enrichment for research and test reactors: Proceedings

    International Nuclear Information System (INIS)

    1993-07-01

    The 15th annual Reduced Enrichment for Research and Test Reactors (RERTR) international meeting was organized by Ris oe National Laboratory in cooperation with the International Atomic Energy Agency and Argonne National Laboratory. The topics of the meeting were the following: National Programs, Fuel Fabrication, Licensing Aspects, States of Conversion, Fuel Testing, and Fuel Cycle. Individual papers have been cataloged separately

  4. Reduced enrichment for research and test reactors: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    1993-07-01

    The 15th annual Reduced Enrichment for Research and Test Reactors (RERTR) international meeting was organized by Ris{o} National Laboratory in cooperation with the International Atomic Energy Agency and Argonne National Laboratory. The topics of the meeting were the following: National Programs, Fuel Fabrication, Licensing Aspects, States of Conversion, Fuel Testing, and Fuel Cycle. Individual papers have been cataloged separately.

  5. Lewis Research Center space station electric power system test facilities

    Science.gov (United States)

    Birchenough, Arthur G.; Martin, Donald F.

    1988-01-01

    NASA Lewis Research Center facilities were developed to support testing of the Space Station Electric Power System. The capabilities and plans for these facilities are described. The three facilities which are required in the Phase C/D testing, the Power Systems Facility, the Space Power Facility, and the EPS Simulation Lab, are described in detail. The responsibilities of NASA Lewis and outside groups in conducting tests are also discussed.

  6. Welding of metallic fuel elements for the irradiation test in JOYO. Preliminary tests and welding execution tests (Joint research)

    International Nuclear Information System (INIS)

    Kikuchi, Hironobu; Nakamura, Kinya; Iwai, Takashi; Arai, Yasuo

    2009-10-01

    Irradiation tests of metallic fuels elements in fast test reactor JOYO are planned under the joint research of Japan Atomic Energy Agency (JAEA) and Central Research Institute of Electric Power Industry (CRIEPI). Six U-Pu-Zr fuel elements clad with ferritic martensitic steel are fabricated in Plutonium Fuel Research Facility (PFRF) of JAEA-Oarai for the first time in Japan. In PFRF, the procedures of fabrication of the fuel elements were determined and the test runs of the equipments were carried out before the welding execution tests for the fuel elements. Test samples for confirming the welding condition between the cladding tube and top and bottom endplugs were prepared, and various test runs were carried out before the welding execution tests. As a result, the welding conditions were finalized by passing the welding execution tests. (author)

  7. A standard for test reliability in group research.

    Science.gov (United States)

    Ellis, Jules L

    2013-03-01

    Many authors adhere to the rule that test reliabilities should be at least .70 or .80 in group research. This article introduces a new standard according to which reliabilities can be evaluated. This standard is based on the costs or time of the experiment and of administering the test. For example, if test administration costs are 7 % of the total experimental costs, the efficient value of the reliability is .93. If the actual reliability of a test is equal to this efficient reliability, the test size maximizes the statistical power of the experiment, given the costs. As a standard in experimental research, it is proposed that the reliability of the dependent variable be close to the efficient reliability. Adhering to this standard will enhance the statistical power and reduce the costs of experiments.

  8. Effects of Bias Modification Training in Binge Eating Disorder.

    Science.gov (United States)

    Schmitz, Florian; Svaldi, Jennifer

    2017-09-01

    Food-related attentional biases have been identified as maintaining factors in binge eating disorder (BED) as they can trigger a binge episode. Bias modification training may reduce symptoms, as it has been shown to be successful in other appetitive disorders. The aim of this study was to assess and modify food-related biases in BED. It was tested whether biases could be increased and decreased by means of a modified dot-probe paradigm, how long such bias modification persisted, and whether this affected subjective food craving. Participants were randomly assigned to a bias enhancement (attend to food stimulus) group or to a bias reduction (avoid food stimulus) group. Food-related attentional bias was found to be successfully reduced in the bias-reduction group, and effects persisted briefly. Additionally, subjective craving for food was influenced by the intervention, and possible mechanisms are discussed. Given these promising initial results, future research should investigate boundary conditions of the experimental intervention to understand how it could complement treatment of BED. Copyright © 2017. Published by Elsevier Ltd.

  9. Obesity, the endocannabinoid system, and bias arising from pharmaceutical sponsorship.

    Science.gov (United States)

    McPartland, John M

    2009-01-01

    Previous research has shown that academic physicians conflicted by funding from the pharmaceutical industry have corrupted evidence based medicine and helped enlarge the market for drugs. Physicians made pharmaceutical-friendly statements, engaged in disease mongering, and signed biased review articles ghost-authored by corporate employees. This paper tested the hypothesis that bias affects review articles regarding rimonabant, an anti-obesity drug that blocks the central cannabinoid receptor. A MEDLINE search was performed for rimonabant review articles, limited to articles authored by USA physicians who served as consultants for the company that manufactures rimonabant. Extracted articles were examined for industry-friendly bias, identified by three methods: analysis with a validated instrument for monitoring bias in continuing medical education (CME); analysis for bias defined as statements that ran contrary to external evidence; and a tally of misrepresentations about the endocannabinoid system. Eight review articles were identified, but only three disclosed authors' financial conflicts of interest, despite easily accessible information to the contrary. The Takhar CME bias instrument demonstrated statistically significant bias in all the review articles. Biased statements that were nearly identical reappeared in the articles, including disease mongering, exaggerating rimonabant's efficacy and safety, lack of criticisms regarding rimonabant clinical trials, and speculations about surrogate markers stated as facts. Distinctive and identical misrepresentations regarding the endocannabinoid system also reappeared in articles by different authors. The findings are characteristic of bias that arises from financial conflicts of interest, and suggestive of ghostwriting by a common author. Resolutions for this scenario are proposed.

  10. Simulating publication bias

    DEFF Research Database (Denmark)

    Paldam, Martin

    is censoring: selection by the size of estimate; SR3 selects the optimal combination of fit and size; and SR4 selects the first satisficing result. The last four SRs are steered by priors and result in bias. The MST and the FAT-PET have been developed for detection and correction of such bias. The simulations......Economic research typically runs J regressions for each selected for publication – it is often selected as the ‘best’ of the regressions. The paper examines five possible meanings of the word ‘best’: SR0 is ideal selection with no bias; SR1 is polishing: selection by statistical fit; SR2...... are made by data variation, while the model is the same. It appears that SR0 generates narrow funnels much at odds with observed funnels, while the other four funnels look more realistic. SR1 to SR4 give the mean a substantial bias that confirms the prior causing the bias. The FAT-PET MRA works well...

  11. Testing of a transport cask for research reactor spent fuel

    International Nuclear Information System (INIS)

    Mourao, Rogerio P.; Silva, Luiz Leite da; Miranda, Carlos A.; Mattar Neto, Miguel; Quintana, Jose F.A.; Saliba, Roberto O.; Novara, Oscar E.

    2011-01-01

    Since the beginning of the last decade three Latin American countries which operate research reactors - Argentina, Brazil and Chile - have been joining efforts to improve the regional capability in the management of spent fuel elements from the reactors operated in the region. As a step in this direction, a packaging for the transport of irradiated fuel from research reactors was designed by a tri-national team and a half-scale model for MTR fuel constructed in Argentina and tested in Brazil. Two test campaigns have been carried out so far, covering both normal conditions of transportation and hypothetical accident conditions. Although the specimen has not successfully performed the tests, its overall performance was considered very satisfactory, and improvements are being introduced to the design. A third test sequence is planned for 2011. (author)

  12. Falsification Testing of Instrumental Variables Methods for Comparative Effectiveness Research.

    Science.gov (United States)

    Pizer, Steven D

    2016-04-01

    To demonstrate how falsification tests can be used to evaluate instrumental variables methods applicable to a wide variety of comparative effectiveness research questions. Brief conceptual review of instrumental variables and falsification testing principles and techniques accompanied by an empirical application. Sample STATA code related to the empirical application is provided in the Appendix. Comparative long-term risks of sulfonylureas and thiazolidinediones for management of type 2 diabetes. Outcomes include mortality and hospitalization for an ambulatory care-sensitive condition. Prescribing pattern variations are used as instrumental variables. Falsification testing is an easily computed and powerful way to evaluate the validity of the key assumption underlying instrumental variables analysis. If falsification tests are used, instrumental variables techniques can help answer a multitude of important clinical questions. © Health Research and Educational Trust.

  13. Testing the Usability of Two Online Research Guides

    Directory of Open Access Journals (Sweden)

    Luigina Vileno

    2011-01-01

    Full Text Available This article describes usability testing of two online research guides. One guide was in the area of applied human sciences and the other was geared toward the discipline of psychology. Six undergraduate students were given several tasks to complete by using the guides. The participants also completed two questionnaires. One described the participants’ demographics and how much time they spent on the Internet on a daily basis. On the other questionnaire, filled out after the usability test, the participants rated the online research guides. Overall, the online research guides were found to be difficult to use. By observing how the participants interacted with the online research guides, the author has identified several problem areas that need to be addressed.

  14. Inconsistencies in quality of life data collection in clinical trials: a potential source of bias? Interviews with research nurses and trialists.

    Science.gov (United States)

    Kyte, Derek; Ives, Jonathan; Draper, Heather; Keeley, Thomas; Calvert, Melanie

    2013-01-01

    Patient-reported outcomes (PROs), such as health-related quality of life (HRQL) are increasingly used to evaluate treatment effectiveness in clinical trials, are valued by patients, and may inform important decisions in the clinical setting. It is of concern, therefore, that preliminary evidence, gained from group discussions at UK-wide Medical Research Council (MRC) quality of life training days, suggests there are inconsistent standards of HRQL data collection in trials and appropriate training and education is often lacking. Our objective was to investigate these reports, to determine if they represented isolated experiences, or were indicative of a potentially wider problem. We undertook a qualitative study, conducting 26 semi-structured interviews with research nurses, data managers, trial coordinators and research facilitators involved in the collection and entry of HRQL data in clinical trials, across one primary care NHS trust, two secondary care NHS trusts and two clinical trials units in the UK. We used conventional content analysis to analyze and interpret our data. Our study participants reported (1) inconsistent standards in HRQL measurement, both between, and within, trials, which appeared to risk the introduction of bias; (2), difficulties in dealing with HRQL data that raised concern for the well-being of the trial participant, which in some instances led to the delivery of non-protocol driven co-interventions, (3), a frequent lack of HRQL protocol content and appropriate training and education of trial staff, and (4) that HRQL data collection could be associated with emotional and/or ethical burden. Our findings suggest there are inconsistencies in the standards of HRQL data collection in some trials resulting from a general lack of HRQL-specific protocol content, training and education. These inconsistencies could lead to biased HRQL trial results. Future research should aim to develop HRQL guidelines and training programmes aimed at supporting

  15. Can DNA-Based Ecosystem Assessments Quantify Species Abundance? Testing Primer Bias and Biomass--Sequence Relationships with an Innovative Metabarcoding Protocol.

    Directory of Open Access Journals (Sweden)

    Vasco Elbrecht

    Full Text Available Metabarcoding is an emerging genetic tool to rapidly assess biodiversity in ecosystems. It involves high-throughput sequencing of a standard gene from an environmental sample and comparison to a reference database. However, no consensus has emerged regarding laboratory pipelines to screen species diversity and infer species abundances from environmental samples. In particular, the effect of primer bias and the detection limit for specimens with a low biomass has not been systematically examined, when processing samples in bulk. We developed and tested a DNA metabarcoding protocol that utilises the standard cytochrome c oxidase subunit I (COI barcoding fragment to detect freshwater macroinvertebrate taxa. DNA was extracted in bulk, amplified in a single PCR step, and purified, and the libraries were directly sequenced in two independent MiSeq runs (300-bp paired-end reads. Specifically, we assessed the influence of specimen biomass on sequence read abundance by sequencing 31 specimens of a stonefly species with known haplotypes spanning three orders of magnitude in biomass (experiment I. Then, we tested the recovery of 52 different freshwater invertebrate taxa of similar biomass using the same standard barcoding primers (experiment II. Each experiment was replicated ten times to maximise statistical power. The results of both experiments were consistent across replicates. We found a distinct positive correlation between species biomass and resulting numbers of MiSeq reads. Furthermore, we reliably recovered 83% of the 52 taxa used to test primer bias. However, sequence abundance varied by four orders of magnitudes between taxa despite the use of similar amounts of biomass. Our metabarcoding approach yielded reliable results for high-throughput assessments. However, the results indicated that primer efficiency is highly species-specific, which would prevent straightforward assessments of species abundance and biomass in a sample. Thus, PCR

  16. Heuristic Biases in Mathematical Reasoning

    Science.gov (United States)

    Inglis, Matthew; Simpson, Adrian

    2005-01-01

    In this paper we briefly describe the dual process account of reasoning, and explain the role of heuristic biases in human thought. Concentrating on the so-called matching bias effect, we describe a piece of research that indicates a correlation between success at advanced level mathematics and an ability to override innate and misleading…

  17. Gender bias affects forests worldwide

    Science.gov (United States)

    Marlène Elias; Susan S Hummel; Bimbika S Basnett; Carol J.P. Colfer

    2017-01-01

    Gender biases persist in forestry research and practice. These biases result in reduced scientific rigor and inequitable, ineffective, and less efficient policies, programs, and interventions. Drawing from a two-volume collection of current and classic analyses on gender in forests, we outline five persistent and inter-related themes: gendered governance, tree tenure,...

  18. Workplace ageism: discovering hidden bias.

    Science.gov (United States)

    Malinen, Sanna; Johnston, Lucy

    2013-01-01

    BACKGROUND/STUDY CONTEXT: Research largely shows no performance differences between older and younger employees, or that older workers even outperform younger employees, yet negative attitudes towards older workers can underpin discrimination. Unfortunately, traditional "explicit" techniques for assessing attitudes (i.e., self-report measures) have serious drawbacks. Therefore, using an approach that is novel to organizational contexts, the authors supplemented explicit with implicit (indirect) measures of attitudes towards older workers, and examined the malleability of both. This research consists of two studies. The authors measured self-report (explicit) attitudes towards older and younger workers with a survey, and implicit attitudes with a reaction-time-based measure of implicit associations. In addition, to test whether attitudes were malleable, the authors measured attitudes before and after a mental imagery intervention, where the authors asked participants in the experimental group to imagine respected and valued older workers from their surroundings. Negative, stable implicit attitudes towards older workers emerged in two studies. Conversely, explicit attitudes showed no age bias and were more susceptible to change intervention, such that attitudes became more positive towards older workers following the experimental manipulation. This research demonstrates the unconscious nature of bias against older workers, and highlights the utility of implicit attitude measures in the context of the workplace. In the current era of aging workforce and skill shortages, implicit measures may be necessary to illuminate hidden workplace ageism.

  19. Examining bias in a test of academic literacy : does the Test of Academic Literacy Levels (TALL) treat students from English and African language backgrounds differently?

    NARCIS (Netherlands)

    Slik, F.W.P. van der; Weideman, A.J.

    2010-01-01

    Responsible test design relies on close examination of a number of parameters of a test. After finding a clearly argued, rational basis (construct) for the ability being tested, then articulating this in detailed specifications for subtests and item types, and subsequently setting benchmarks for

  20. Integrating enhanced hepatitis C testing and counselling in research.

    Science.gov (United States)

    Winter, Rebecca; Nguyen, Oanh; Higgs, Peter; Armstrong, Stuart; Duong, Duyen; Thach, My Li; Aitken, Campbell; Hellard, Margaret

    2008-02-01

    The hepatitis C virus (HCV) affects over 170 million people worldwide. In Australia, over 225,000 people have been diagnosed with HCV infection with 13,000 infections reported annually; 90% are attributed to injecting drug use. Burnet Institute (BI) researchers have been studying the HCV epidemic since the virus was identified in 1989 including community based cohort studies (1990-1995), numerous studies involving Vietnamese-Australian people who inject drugs (PWID) (1996-2004) and social network studies (2000-2002, 2005-2007). Through this work the BI has developed a model of research practice for HCV and PWID, developed in recognition that much research relating to BBV infections - and HCV in particular - could be improved in terms of provision of test results to study participants. Our model endeavours to provide all participants with the highest quality HCV test results, delivered in accordance with best practice for pre- and post-test counselling by engaging participants in environments in which they are comfortable, building trust and rapport and being available throughout and beyond the research study. This paper will discuss the benefits and lessons learned over numerous studies in providing pre- and post-test counselling to PWID in an outreach capacity.

  1. Research issues in the automated testing of Ajax applications

    NARCIS (Netherlands)

    Van Deursen, A.; Mesbah, A.

    2009-01-01

    Note: This paper is a pre-print of: Arie van Deursen and Ali Mesbah. Research Issues in the Automated Testing of Ajax Applications. In Proceedings 36th International Conference on Current Trend in Theory and Practice of Computer Science (SOFSEM), pp. 16-28. Lecture Notes in Computer Science 5901,

  2. Alternatives to Animal Use in Research, Testing, and Education. Summary.

    Science.gov (United States)

    Congress of the U.S., Washington, DC. Office of Technology Assessment.

    With an estimated 17-22 million animals used in laboratories annually in the United States, public interest in animal welfare has sparked an often emotional debate over such uses of animals. Concerns focus on balancing societal needs for continued progress in biomedical and behavioral research, for toxicity testing to safeguard the public, and for…

  3. Present status of high temperature engineering test and research, 1994

    International Nuclear Information System (INIS)

    1994-10-01

    High temperature gas-cooled reactors have excellent features such as the generation of high temperature close to 1000degC, very high inherent safety and high fuel burnup. By the advanced basic research under high temperature irradiation condition, the creation of various new technologies which become the momentum of future technical innovation can be expected. The construction of the high temperature engineering test reactor (HTTR) was decided in 1987, which aims at the thermal output of 30 MW and the coolant temperature at reactor exit of 950degC. The initial criticality is scheduled in 1998. Japan Atomic Energy Research Institute has advanced the high temperature engineering test and research, and plans the safety verifying test of the HTTR, the test of connecting heat utilization plants and so on. In this report, mainly the results obtained for one year from May, 1993 are summarized. The outline of the high temperature engineering test and development of the HTTR technologies are reported. (K.I.)

  4. Bias modification training can alter approach bias and chocolate consumption.

    Science.gov (United States)

    Schumacher, Sophie E; Kemps, Eva; Tiggemann, Marika

    2016-01-01

    Recent evidence has demonstrated that bias modification training has potential to reduce cognitive biases for attractive targets and affect health behaviours. The present study investigated whether cognitive bias modification training could be applied to reduce approach bias for chocolate and affect subsequent chocolate consumption. A sample of 120 women (18-27 years) were randomly assigned to an approach-chocolate condition or avoid-chocolate condition, in which they were trained to approach or avoid pictorial chocolate stimuli, respectively. Training had the predicted effect on approach bias, such that participants trained to approach chocolate demonstrated an increased approach bias to chocolate stimuli whereas participants trained to avoid such stimuli showed a reduced bias. Further, participants trained to avoid chocolate ate significantly less of a chocolate muffin in a subsequent taste test than participants trained to approach chocolate. Theoretically, results provide support for the dual process model's conceptualisation of consumption as being driven by implicit processes such as approach bias. In practice, approach bias modification may be a useful component of interventions designed to curb the consumption of unhealthy foods. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. ATIS Market Research: A Survey of Operational Tests and University and Government Research

    Science.gov (United States)

    1994-03-01

    This report outlines research that examines the market for Advanced Traveler Information Systems (ATIS). The report includes detailed descriptions of Pathfinder, TravTek, and SmarTraveler ATIS operational tests. It includes basic background informati...

  6. The researcher and the consultant: from testing to probability statements.

    Science.gov (United States)

    Hamra, Ghassan B; Stang, Andreas; Poole, Charles

    2015-09-01

    In the first instalment of this series, Stang and Poole provided an overview of Fisher significance testing (ST), Neyman-Pearson null hypothesis testing (NHT), and their unfortunate and unintended offspring, null hypothesis significance testing. In addition to elucidating the distinction between the first two and the evolution of the third, the authors alluded to alternative models of statistical inference; namely, Bayesian statistics. Bayesian inference has experienced a revival in recent decades, with many researchers advocating for its use as both a complement and an alternative to NHT and ST. This article will continue in the direction of the first instalment, providing practicing researchers with an introduction to Bayesian inference. Our work will draw on the examples and discussion of the previous dialogue.

  7. Shear behavior of thermoformed woven-textile thermoplastic prepregs: An analysis combining bias-extension test and X-ray microtomography

    Science.gov (United States)

    Gassoumi, M.; Rolland du Roscoat, S.; Casari, P.; Dumont, P. J. J.; Orgéas, L.; Jacquemin, F.

    2017-10-01

    Thermoforming allows the manufacture of structural parts for the automotive and aeronautical domains using long fiber thermoplastic prepregs with short cycle times. During this operation, several sheets of molten prepregs are stacked and subjected to large macroscale strains, mainly via in-plane shear, out-of-plane consolidation or dilatation, and bending of the fibrous reinforcement. These deformation modes and the related meso and microstructure evolutions are still poorly understood. However, they can drastically alter the end-use macroscale properties of fabricated parts. To better understand these phenomena, bias extension tests were performed using specimens made of several stacked layers of glass woven fabrics and polyamide matrix. The macroscale shear behavior of these prepregs was investigated at various temperatures. A multiscale analysis of deformed samples was performed using X-ray microtomography images of the deformed specimens acquired at two different spatial resolutions. The low-resolution images were used to analyze the deformation mechanisms and the structural characteristics of prepregs at the macroscale and bundle scales. It was possible to analyze the 3D shapes of deformed samples and, in particular, the spatial variations of their thickness so as to quantify the out-of-plane dilatancy or consolidation phenomena induced by the in-plane shear of prepregs. At a lower scale, the analysis of the high-resolution images showed that these mechanisms were accompanied by the growth of pores and the deformation of fiber bundles. The orientation of the fiber bundles and its through-thickness evolution were measured along the weft and warp directions in the deformed samples, allowing the relevance of geometrical models currently used to analyze bias extension tests to be discussed. Results can be used to enhance the current rheological models for the prediction of thermoforming of thermoplastic prepregs.

  8. Good research practices for comparative effectiveness research: approaches to mitigate bias and confounding in the design of nonrandomized studies of treatment effects using secondary data sources: the International Society for Pharmacoeconomics and Outcomes Research Good Research Practices for Retrospective Database Analysis Task Force Report--Part II.

    Science.gov (United States)

    Cox, Emily; Martin, Bradley C; Van Staa, Tjeerd; Garbe, Edeltraut; Siebert, Uwe; Johnson, Michael L

    2009-01-01

    The goal of comparative effectiveness analysis is to examine the relationship between two variables, treatment, or exposure and effectiveness or outcome. Unlike data obtained through randomized controlled trials, researchers face greater challenges with causal inference with observational studies. Recognizing these challenges, a task force was formed to develop a guidance document on methodological approaches to addresses these biases. The task force was commissioned and a Chair was selected by the International Society for Pharmacoeconomics and Outcomes Research Board of Directors in October 2007. This report, the second of three reported in this issue of the Journal, discusses the inherent biases when using secondary data sources for comparative effectiveness analysis and provides methodological recommendations to help mitigate these biases. The task force report provides recommendations and tools for researchers to mitigate threats to validity from bias and confounding in measurement of exposure and outcome. Recommendations on design of study included: the need for data analysis plan with causal diagrams; detailed attention to classification bias in definition of exposure and clinical outcome; careful and appropriate use of restriction; extreme care to identify and control for confounding factors, including time-dependent confounding. Design of nonrandomized studies of comparative effectiveness face several daunting issues, including measurement of exposure and outcome challenged by misclassification and confounding. Use of causal diagrams and restriction are two techniques that can improve the theoretical basis for analyzing treatment effects in study populations of more homogeneity, with reduced loss of generalizability.

  9. A narrative review of manual muscle testing and implications for muscle testing research.

    Science.gov (United States)

    Conable, Katharine M; Rosner, Anthony L

    2011-09-01

    Manual muscle testing (MMT) is used for a variety of purposes in health care by medical, osteopathic, chiropractic, physical therapy, rehabilitation, and athletic training professionals. The purpose of this study is to provide a narrative review of variations in techniques, durations, and forces used in MMT putting applied kinesiology (AK) muscle testing in context and highlighting aspects of muscle testing important to report in MMT research. PubMed, the Collected Papers of the International College of Applied Kinesiology-USA, and related texts were searched on the subjects of MMT, maximum voluntary isometric contraction testing, and make/break testing. Force parameters (magnitude, duration, timing of application), testing variations of MMT, and normative data were collected and evaluated. "Break" tests aim to evaluate the muscle's ability to resist a gradually increasing pressure and may test different aspects of neuromuscular control than tests against fixed resistances. Applied kinesiologists use submaximal manual break tests and a binary grading scale to test short-term changes in muscle function in response to challenges. Many of the studies reviewed were not consistent in reporting parameters for testing. To increase the chances for replication, studies using MMT should specify parameters of the tests used, such as exact procedures and instrumentation, duration of test, peak force, and timing of application of force. Copyright © 2011 National University of Health Sciences. Published by Elsevier Inc. All rights reserved.

  10. THE BIAS (BULLYING IN SICILIAN SCHOOL PILOT STUDY: INVESTIGATING THE PREVALENCE OF BULLYING IN SCHOOL OF PALERMO CITY. A RESEARCH STUDY PROTOCOL.

    Directory of Open Access Journals (Sweden)

    Claudio Costantino

    2017-12-01

    Full Text Available Bullying in school, being a serious threat to physical and emotional health of children and adolescents all over the world, represents an important public health issue. In Italy, since 2007, the Italian Ministry of Education promotes activities to fight against and to prevent bullying in schools of all levels and, at the same time, also Health Authorities are trying to implement effective social-health responses. However, to date, the lack of consistent data, from national to local level, that could help in describing the problem in a proper manner, does not allow a systematic bullying surveillance and so also measuring the effectiveness of the public health strategy that could be implemented. The Bias pilot study’s aim is to evaluate the prevalence of bullying in a sample of schools in the city of Palermo, the largest in Sicily, and to investigate its characteristics in relation to different types of school. Finally, the Bias study aim to evaluate the feasibility of alternative methods for the detection of the prevalence of bullying phenomenon in schools. Here we present the research protocol and the questionnaires that will be used.

  11. Affective Biases in Humans and Animals.

    Science.gov (United States)

    Robinson, E S J; Roiser, J P

    Depression is one of the most common but poorly understood psychiatric conditions. Although drug treatments and psychological therapies are effective in some patients, many do not achieve full remission and some patients receive no apparent benefit. Developing new improved treatments requires a better understanding of the aetiology of symptoms and evaluation of novel therapeutic targets in pre-clinical studies. Recent developments in our understanding of the basic cognitive processes that may contribute to the development of depression and its treatment offer new opportunities for both clinical and pre-clinical research. This chapter discusses the clinical evidence supporting a cognitive neuropsychological model of depression and antidepressant efficacy, and how this information may be usefully translated to pre-clinical investigation. Studies using neuropsychological tests in depressed patients and at risk populations have revealed basic negative emotional biases and disrupted reward and punishment processing, which may also impact on non-affective cognition. These affective biases are sensitive to antidepressant treatments with early onset effects observed, suggesting an important role in recovery. This clinical work into affective biases has also facilitated back-translation to animals and the development of assays to study affective biases in rodents. These animal studies suggest that, similar to humans, rodents in putative negative affective states exhibit negative affective biases on decision-making and memory tasks. Antidepressant treatments also induce positive biases in these rodent tasks, supporting the translational validity of this approach. Although still in the early stages of development and validation, affective biases in depression have the potential to offer new insights into the clinical condition, as well as facilitating the development of more translational approaches for pre-clinical studies.

  12. What is the ARM Climate Research Facility: Is Global Warming a Real Bias or a Statistical Anomaly?

    Energy Technology Data Exchange (ETDEWEB)

    Egami, Takeshi [U of Tennessee and ORNL; Sisterson, Douglas L.

    2010-03-10

    The Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) is a U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research national user facility. With multi-laboratory management of distributed facilities worldwide, the ACRF does not fit the mold of a traditional user facility located at a national laboratory. The ACRF provides the world's most comprehensive 24/7 observational capabilities for obtaining atmospheric data specifically for climate change research. Serving nearly 5,000 registered users from 15 federal and state agencies, 375 universities, and 67 countries, the ACRF Data Archive collects and delivers over 5 terabytes of data per month to its users. The ACRF users provide critical information about cloud formation processes, water vapor, and aerosols, and their influence on radiative transfer in the atmosphere. This information is used to improve global climate model predictions of climate change.

  13. Small Radioisotope Power System Testing at NASA Glenn Research Center

    Science.gov (United States)

    Dugala, Gina; Bell, Mark; Oriti, Salvatore; Fraeman, Martin; Frankford, David; Duven, Dennis

    2013-01-01

    In April 2009, NASA Glenn Research Center (GRC) formed an integrated product team (IPT) to develop a Small Radioisotope Power System (SRPS) utilizing a single Advanced Stirling Convertor (ASC) with passive balancer. A single ASC produces approximately 80 We making this system advantageous for small distributed lunar science stations. The IPT consists of Sunpower, Inc., to provide the single ASC with a passive balancer, The Johns Hopkins University Applied Physics Laboratory (JHUAPL) to design an engineering model Single Convertor Controller (SCC) for an ASC with a passive balancer, and NASA GRC to provide technical support to these tasks and to develop a simulated lunar lander test stand. The single ASC with a passive balancer, simulated lunar lander test stand, and SCC were delivered to GRC and were tested as a system. The testing sequence at GRC included SCC fault tolerance, integration, electromagnetic interference (EMI), vibration, and extended operation testing. The SCC fault tolerance test characterized the SCCs ability to handle various fault conditions, including high or low bus power consumption, total open load or short circuit, and replacing a failed SCC card while the backup maintains control of the ASC. The integrated test characterized the behavior of the system across a range of operating conditions, including variations in cold-end temperature and piston amplitude, including the emitted vibration to both the sensors on the lunar lander and the lunar surface. The EMI test characterized the AC and DC magnetic and electric fields emitted by the SCC and single ASC. The vibration test confirms the SCCs ability to control the single ASC during launch. The extended operation test allows data to be collected over a period of thousands of hours to obtain long term performance data of the ASC with a passive balancer and the SCC. This paper will discuss the results of each of these tests.

  14. PREPARE: guidelines for planning animal research and testing.

    Science.gov (United States)

    Smith, Adrian J; Clutton, R Eddie; Lilley, Elliot; Hansen, Kristine E Aa; Brattelid, Trond

    2018-04-01

    There is widespread concern about the quality, reproducibility and translatability of studies involving research animals. Although there are a number of reporting guidelines available, there is very little overarching guidance on how to plan animal experiments, despite the fact that this is the logical place to start ensuring quality. In this paper we present the PREPARE guidelines: Planning Research and Experimental Procedures on Animals: Recommendations for Excellence. PREPARE covers the three broad areas which determine the quality of the preparation for animal studies: formulation, dialogue between scientists and the animal facility, and quality control of the various components in the study. Some topics overlap and the PREPARE checklist should be adapted to suit specific needs, for example in field research. Advice on use of the checklist is available on the Norecopa website, with links to guidelines for animal research and testing, at https://norecopa.no/PREPARE .

  15. [Development of a microenvironment test chamber for airborne microbe research].

    Science.gov (United States)

    Zhan, Ningbo; Chen, Feng; Du, Yaohua; Cheng, Zhi; Li, Chenyu; Wu, Jinlong; Wu, Taihu

    2017-10-01

    One of the most important environmental cleanliness indicators is airborne microbe. However, the particularity of clean operating environment and controlled experimental environment often leads to the limitation of the airborne microbe research. This paper designed and implemented a microenvironment test chamber for airborne microbe research in normal test conditions. Numerical simulation by Fluent showed that airborne microbes were evenly dispersed in the upper part of test chamber, and had a bottom-up concentration growth distribution. According to the simulation results, the verification experiment was carried out by selecting 5 sampling points in different space positions in the test chamber. Experimental results showed that average particle concentrations of all sampling points reached 10 7 counts/m 3 after 5 minutes' distributing of Staphylococcus aureus , and all sampling points showed the accordant mapping of concentration distribution. The concentration of airborne microbe in the upper chamber was slightly higher than that in the middle chamber, and that was also slightly higher than that in the bottom chamber. It is consistent with the results of numerical simulation, and it proves that the system can be well used for airborne microbe research.

  16. A shift from significance test to hypothesis test through power analysis in medical research.

    Science.gov (United States)

    Singh, G

    2006-01-01

    Medical research literature until recently, exhibited substantial dominance of the Fisher's significance test approach of statistical inference concentrating more on probability of type I error over Neyman-Pearson's hypothesis test considering both probability of type I and II error. Fisher's approach dichotomises results into significant or not significant results with a P value. The Neyman-Pearson's approach talks of acceptance or rejection of null hypothesis. Based on the same theory these two approaches deal with same objective and conclude in their own way. The advancement in computing techniques and availability of statistical software have resulted in increasing application of power calculations in medical research and thereby reporting the result of significance tests in the light of power of the test also. Significance test approach, when it incorporates power analysis contains the essence of hypothesis test approach. It may be safely argued that rising application of power analysis in medical research may have initiated a shift from Fisher's significance test to Neyman-Pearson's hypothesis test procedure.

  17. A shift from significance test to hypothesis test through power analysis in medical research

    Directory of Open Access Journals (Sweden)

    Singh Girish

    2006-01-01

    Full Text Available Medical research literature until recently, exhibited substantial dominance of the Fisher′s significance test approach of statistical inference concentrating more on probability of type I error over Neyman-Pearson′s hypothesis test considering both probability of type I and II error. Fisher′s approach dichotomises results into significant or not significant results with a P value. The Neyman-Pearson′s approach talks of acceptance or rejection of null hypothesis. Based on the same theory these two approaches deal with same objective and conclude in their own way. The advancement in computing techniques and availability of statistical software have resulted in increasing application of power calculations in medical research and thereby reporting the result of significance tests in the light of power of the test also. Significance test approach, when it incorporates power analysis contains the essence of hypothesis test approach. It may be safely argued that rising application of power analysis in medical research may have initiated a shift from Fisher′s significance test to Neyman-Pearson′s hypothesis test procedure.

  18. Continued research, development and test of SOFC Technology. Final report

    Energy Technology Data Exchange (ETDEWEB)

    2008-09-15

    The aim of the project was to further develop the SOFC cell and stack technology and drive down manufacturing costs in order to accomplish the performance and economic targets set forward in the SOFC road map, which has been developed in collaboration with the national Danish SOFC Strategy group. The project was divided into four parts. Part 1, Continued cell development covered the successful development of larger cells with a 500 cm2 footprint. Part 2, Cell manufacturing covered the production of 9.859 equivalents (12x12 cm2 standard cells) that were used in the stacks for demonstration projects (EFP 33033-0050)and for in-house research, development and testing in this project. Part 3, Continued stack development covered the successful test of a 3 kW{sub e} stack as well as the planning of a >8.000 hours stack test with new stack technology. The >8.000 hours test that started after the end date for this project will last for 12 months and be reported in the PSO 2008-1-010049 project. Part 4, Stack manufacturing covered a number of small stacks for in-house research, development and testing. (auther)

  19. Deep Borehole Field Test Research Activities at LBNL

    Energy Technology Data Exchange (ETDEWEB)

    Dobson, Patrick [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Tsang, Chin-Fu [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Kneafsey, Timothy [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Borglin, Sharon [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Piceno, Yvette [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Andersen, Gary [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Nakagawa, Seiji [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Nihei, Kurt [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Rutqvist, Jonny [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Doughty, Christine [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Reagan, Matthew [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2016-08-19

    The goal of the U.S. Department of Energy Used Fuel Disposition’s (UFD) Deep Borehole Field Test is to drill two 5 km large-diameter boreholes: a characterization borehole with a bottom-hole diameter of 8.5 inches and a field test borehole with a bottom-hole diameter of 17 inches. These boreholes will be used to demonstrate the ability to drill such holes in crystalline rocks, effectively characterize the bedrock repository system using geophysical, geochemical, and hydrological techniques, and emplace and retrieve test waste packages. These studies will be used to test the deep borehole disposal concept, which requires a hydrologically isolated environment characterized by low permeability, stable fluid density, reducing fluid chemistry conditions, and an effective borehole seal. During FY16, Lawrence Berkeley National Laboratory scientists conducted a number of research studies to support the UFD Deep Borehole Field Test effort. This work included providing supporting data for the Los Alamos National Laboratory geologic framework model for the proposed deep borehole site, conducting an analog study using an extensive suite of geoscience data and samples from a deep (2.5 km) research borehole in Sweden, conducting laboratory experiments and coupled process modeling related to borehole seals, and developing a suite of potential techniques that could be applied to the characterization and monitoring of the deep borehole environment. The results of these studies are presented in this report.

  20. What does social research say about high-stakes tests?

    Directory of Open Access Journals (Sweden)

    Rafael Feito Alonso

    2017-03-01

    Full Text Available High-stake tests, which students need to pass in order to gain a Secondary education certificate, have aroused a lot of controversy whenever they have been implemented. Especially in the USA these tests have produced a dramatic shrinking of school knowledge as they have been focused into questions posed by the very tests. At the same time, there has been a critical modification of the learning processes due to the fact that these tests encourage students to pay more attention to factual knowledge, which is far away from hands-on learning, debating in class or working in teams. In spite of certain discrepancies, by and large, research casts serious doubts about whether these tests are conductive to better academic performance. Nevertheless, the dropout rate is on the rise. More often than not, school principals have been found preventing struggling students to sit the exams. A review of the research into this matter allows us to put into context the debate surrounding external exams posed by the current education law (LOMCE: Law for the Improvement of Educational Quality passed by the parliamentary majority of the Popular Party in Spain in 2013.

  1. Deep Borehole Field Test Research Activities at LBNL

    International Nuclear Information System (INIS)

    Dobson, Patrick; Tsang, Chin-Fu; Kneafsey, Timothy; Borglin, Sharon; Piceno, Yvette; Andersen, Gary; Nakagawa, Seiji; Nihei, Kurt; Rutqvist, Jonny; Doughty, Christine; Reagan, Matthew

    2016-01-01

    The goal of the U.S. Department of Energy Used Fuel Disposition's (UFD) Deep Borehole Field Test is to drill two 5 km large-diameter boreholes: a characterization borehole with a bottom-hole diameter of 8.5 inches and a field test borehole with a bottom-hole diameter of 17 inches. These boreholes will be used to demonstrate the ability to drill such holes in crystalline rocks, effectively characterize the bedrock repository system using geophysical, geochemical, and hydrological techniques, and emplace and retrieve test waste packages. These studies will be used to test the deep borehole disposal concept, which requires a hydrologically isolated environment characterized by low permeability, stable fluid density, reducing fluid chemistry conditions, and an effective borehole seal. During FY16, Lawrence Berkeley National Laboratory scientists conducted a number of research studies to support the UFD Deep Borehole Field Test effort. This work included providing supporting data for the Los Alamos National Laboratory geologic framework model for the proposed deep borehole site, conducting an analog study using an extensive suite of geoscience data and samples from a deep (2.5 km) research borehole in Sweden, conducting laboratory experiments and coupled process modeling related to borehole seals, and developing a suite of potential techniques that could be applied to the characterization and monitoring of the deep borehole environment. The results of these studies are presented in this report.

  2. Administrative bias in South Africa

    Directory of Open Access Journals (Sweden)

    E S Nwauche

    2005-01-01

    Full Text Available This article reviews the interpretation of section 6(2(aii of the Promotion of Administrative Justice Act which makes an administrator “biased or reasonably suspected of bias” a ground of judicial review. In this regard, the paper reviews the determination of administrative bias in South Africa especially highlighting the concept of institutional bias. The paper notes that inspite of the formulation of the bias ground of review the test for administrative bias is the reasonable apprehension test laid down in the case of President of South Africa v South African Rugby Football Union(2 which on close examination is not the same thing. Accordingly the paper urges an alternative interpretation that is based on the reasonable suspicion test enunciated in BTR Industries South Africa (Pty Ltd v Metal and Allied Workers Union and R v Roberts. Within this context, the paper constructs a model for interpreting the bias ground of review that combines the reasonable suspicion test as interpreted in BTR Industries and R v Roberts, the possibility of the waiver of administrative bias, the curative mechanism of administrative appeal as well as some level of judicial review exemplified by the jurisprudence of article 6(1 of the European Convention of Human Rights, especially in the light of the contemplation of the South African Magistrate Court as a jurisdictional route of judicial review.

  3. Homogenisation in project management for large German research projects in the Earth system sciences: overcoming the institutional coordination bias

    Science.gov (United States)

    Rauser, Florian; Vamborg, Freja

    2016-04-01

    The interdisciplinary project on High Definition Clouds and Precipitation for advancing climate prediction HD(CP)2 (hdcp2.eu) is an example for the trend in fundamental research in Europe to increasingly focus on large national and international research programs that require strong scientific coordination. The current system has traditionally been host-based: project coordination activities and funding is placed at the host institute of the central lead PI of the project. This approach is simple and has the advantage of strong collaboration between project coordinator and lead PI, while exhibiting a list of strong, inherent disadvantages that are also mentioned in this session's description: no community best practice development, lack of integration between similar projects, inefficient methodology development and usage, and finally poor career development opportunities for the coordinators. Project coordinators often leave the project before it is finalized, leaving some of the fundamentally important closing processes to the PIs. This systematically prevents the creation of professional science management expertise within academia, which leads to an automatic imbalance that hinders the outcome of large research programs to help future funding decisions. Project coordinators in academia often do not work in a professional project office environment that could distribute activities and use professional tools and methods between different projects. Instead, every new project manager has to focus on methodological work anew (communication infrastructure, meetings, reporting), even though the technological needs of large research projects are similar. This decreases the efficiency of the coordination and leads to funding that is effectively misallocated. We propose to challenge this system by creating a permanent, virtual "Centre for Earth System Science Management CESSMA" (cessma.com), and changing the approach from host- based to centre-based. This should

  4. Fuels for research and test reactors, status review: July 1982

    International Nuclear Information System (INIS)

    Stahl, D.

    1982-12-01

    A thorough review is provided on nuclear fuels for steady-state thermal research and test reactors. The review was conducted to provide a documented data base in support of recent advances in research and test reactor fuel development, manufacture, and demonstration in response to current US policy on availability of enriched uranium. The review covers current fabrication practice, fabrication development efforts, irradiation performance, and properties affecting fuel utilization, including thermal conductivity, specific heat, density, thermal expansion, corrosion, phase stability, mechanical properties, and fission-product release. The emphasis is on US activities, but major work in Europe and elsewhere is included. The standard fuel types discussed are the U-Al alloy, UZrH/sub x/, and UO 2 rod fuels. Among new fuels, those given major emphasis include H 3 Si-Al dispersion and UO 2 caramel plate fuels

  5. Federal laboratory nondestructive testing research and development applicable to industry

    Energy Technology Data Exchange (ETDEWEB)

    Smith, S.A.; Moore, N.L.

    1987-02-01

    This document presents the results of a survey of nondestructive testing (NDT) and related sensor technology research and development (R and D) at selected federal laboratories. Objective was to identify and characterize NDT activities that could be applied to improving energy efficiency and overall productivity in US manufacturing. Numerous federally supported R and D programs were identified in areas such as acoustic emissions, eddy current, radiography, computer tomography and ultrasonics. A Preliminary Findings Report was sent to industry representatives, which generated considerable interest.

  6. Situation of test and research reactors' spent fuels

    International Nuclear Information System (INIS)

    Shimizu, Kenichi; Uchiyama, Junzo; Sato, Hiroshi

    1996-01-01

    The U.S. DOE decided a renewal Off-Site Fuel Policy for stopping to spread a highly enriched uranium which was originally enriched at the U.S., the policy declared that to receive all HEU spent fuels from Test and Research reactors in all the world. In Japan, under bilateral agreement of cooperation between the government of the United States and the government of Japan concerning peaceful uses of nuclear energy, the highly enriched uranium of Test and Research Reactors' fuels was purchased from the U.S. and the fuels had been manufactured in Japan, America, Germany and France. On the other hand, a former president of the U.S. J. Carter proposed that to convert the fuels from HEU to LEU concerning a nonproliferation of nuclear materials in 1978, and Japan absolutely supported this policy. Under this condition, the U.S. stopped to receive the spent fuels from the other countries concerning legal action to the Off-Site Fuels Policy. As a result, the spent fuels are increasing, and to cross to each reactor's storage capacity, and if this policy start, a faced crisis of Test and Research Reactors will be avoided. (author)

  7. Cognitive bias in action: evidence for a reciprocal relation between confirmation bias and fear in children.

    Science.gov (United States)

    Remmerswaal, Danielle; Huijding, Jorg; Bouwmeester, Samantha; Brouwer, Marlies; Muris, Peter

    2014-03-01

    Some cognitive models propose that information processing biases and fear are reciprocally related. This idea has never been formally tested. Therefore, this study investigated the existence of a vicious circle by which confirmation bias and fear exacerbate each other. One-hundred-and-seventy-one school children (8-13 years) were first provided with threatening, ambiguous, or positive information about an unknown animal. Then they completed a computerized information search task during which they could collect additional (negative, positive, or neutral) information about the novel animal. Because fear levels were repeatedly assessed during the task, it was possible to examine the reciprocal relationship between confirmation bias and fear. A reciprocal relation of mutual reinforcement was found between confirmation bias and fear over the course of the experiment: increases in fear predicted subsequent increases in the search for negative information, and increases in the search for negative information further enhanced fear on a later point-in-time. In addition, the initial information given about the animals successfully induced diverging fear levels in the children, and determined their first inclination to search for additional information. As this study employed a community sample of primary school children, future research should test whether these results can be generalized to clinically anxious youth. These findings provide first support for the notion that fearful individuals may become trapped in a vicious circle in which fear and a fear-related confirmation bias mutually strengthen each other, thereby maintaining the anxiety pathology. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Microgrids research: A review of experimental microgrids and test systems

    Energy Technology Data Exchange (ETDEWEB)

    Lidula, N.W.A.; Rajapakse, A.D. [Department of Electrical and Computer Engineering, 75A Chancellor' s Circle, University of Manitoba, Winnipeg, Manitoba R3T 5V6 (Canada)

    2011-01-15

    A microgrid is particularly a portion of the power distribution system that comprises distributed generation, energy storage and loads. To be capable of operating in parallel to the grid, as an autonomous power island and in transition modes, microgrids must be robust in controlling the local voltage and frequency, and protecting the network and equipment connected to the microgrid. It also needs to facilitate demand side management and resynchronization. This paper presents a review of existing microgrid test networks around the world (North America, Europe and Asia) and some significantly different microgrid simulation networks present in the literature. Paper is focused on the test systems and available microgrid control options. A summary table comparing and contrasting the existing test systems is presented. The paper is concluded highlighting the worthy findings and possible areas of research that would enhance practical use of microgrid facilities. (author)

  9. Research and test facilities required in nuclear science and technology

    International Nuclear Information System (INIS)

    2009-01-01

    Experimental facilities are essential research tools both for the development of nuclear science and technology and for testing systems and materials which are currently being used or will be used in the future. As a result of economic pressures and the closure of older facilities, there are concerns that the ability to undertake the research necessary to maintain and to develop nuclear science and technology may be in jeopardy. An NEA expert group with representation from ten member countries, the International Atomic Energy Agency and the European Commission has reviewed the status of those research and test facilities of interest to the NEA Nuclear Science Committee. They include facilities relating to nuclear data measurement, reactor development, neutron scattering, neutron radiography, accelerator-driven systems, transmutation, nuclear fuel, materials, safety, radiochemistry, partitioning and nuclear process heat for hydrogen production. This report contains the expert group's detailed assessment of the current status of these nuclear research facilities and makes recommendations on how future developments in the field can be secured through the provision of high-quality, modern facilities. It also describes the online database which has been established by the expert group which includes more than 700 facilities. (authors)

  10. Reduced enrichment for research and test reactors: Proceedings

    International Nuclear Information System (INIS)

    1988-05-01

    The international effort to develop new research reactor fuel materials and designs based on the use of low-enriched uranium, instead of highly-enriched uranium, has made much progress during the eight years since its inception. To foster direct communication and exchange of ideas among the specialist in this area, the Reduced Enrichment Research and Test Reactor (RERTR) Program, at the Argonne National Laboratory, sponsored this meeting as the ninth of a series which began in 1978. All previous meetings of this series are listed on the facing page. The focus of this meeting was on the LEU fuel demonstration which was in progress at the Oak Ridge Research (ORR) reactor, not far from where the meeting was held. The visit to the ORR, where a silicide LEU fuel with 4.8 g A/cm 3 was by then in routine use, illustrated how far work has progressed

  11. Reduced enrichment for research and test reactors: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    1988-05-01

    The international effort to develop new research reactor fuel materials and designs based on the use of low-enriched uranium, instead of highly-enriched uranium, has made much progress during the eight years since its inception. To foster direct communication and exchange of ideas among the specialist in this area, the Reduced Enrichment Research and Test Reactor (RERTR) Program, at the Argonne National Laboratory, sponsored this meeting as the ninth of a series which began in 1978. All previous meetings of this series are listed on the facing page. The focus of this meeting was on the LEU fuel demonstration which was in progress at the Oak Ridge Research (ORR) reactor, not far from where the meeting was held. The visit to the ORR, where a silicide LEU fuel with 4.8 g A/cm/sup 3/ was by then in routine use, illustrated how far work has progressed.

  12. Strengthening forensic DNA decision making through a better understanding of the influence of cognitive bias.

    Science.gov (United States)

    Jeanguenat, Amy M; Budowle, Bruce; Dror, Itiel E

    2017-11-01

    Cognitive bias may influence process flows and decision making steps in forensic DNA analyses and interpretation. Currently, seven sources of bias have been identified that may affect forensic decision making with roots in human nature; environment, culture, and experience; and case specific information. Most of the literature and research on cognitive bias in forensic science has focused on patterned evidence; however, forensic DNA testing is not immune to bias, especially when subjective interpretation is involved. DNA testing can be strengthened by recognizing the existence of bias, evaluating where it influences decision making, and, when applicable, implementing practices to reduce or control its effects. Elements that may improve forensic decision making regarding bias include cognitively informed education and training, quality assurance procedures, review processes, analysis and interpretation, and context management of irrelevant information. Although bias exists, reliable results often can be (and have been) produced. However, at times bias can (and has) impacted the interpretation of DNA results negatively. Therefore, being aware of the dangers of bias and implementing measures to control its potential impact should be considered. Measures and procedures that handicap the workings of the crime laboratory or add little value to improving the operation are not advocated, but simple yet effective measures are suggested. This article is meant to raise awareness of cognitive bias contamination in forensic DNA testing and to give laboratories possible pathways to make sound decisions to address its influences. Copyright © 2017 The Chartered Society of Forensic Sciences. Published by Elsevier B.V. All rights reserved.

  13. Research process of nondestructive testing pitting corrosion in metal material

    Directory of Open Access Journals (Sweden)

    Bo ZHANG

    2017-12-01

    Full Text Available Pitting corrosion directly affects the usability and service life of metal material, so the effective nondestructive testing and evaluation on pitting corrosion is of great significance for fatigue life prediction because of data supporting. The features of pitting corrosion are elaborated, and the relation between the pitting corrosion parameters and fatigue performance is pointed out. Through introducing the fundamental principles of pitting corrosion including mainly magnetic flux leakage inspection, pulsed eddy current and guided waves, the research status of nondestructive testing technology for pitting corrosion is summarized, and the key steps of nondestructive testing technologies are compared and analyzed from the theoretical model, signal processing to industrial applications. Based on the analysis of the signal processing specificity of different nondestructive testing technologies in detecting pitting corrosion, the visualization combined with image processing and signal analysis are indicated as the critical problems of accurate extraction of pitting defect information and quantitative characterization for pitting corrosion. The study on non-contact nondestructive testing technologies is important for improving the detection precision and its application in industries.

  14. Materials Science Research Rack-1 Fire Suppressant Distribution Test Report

    Science.gov (United States)

    Wieland, P. O.

    2002-01-01

    Fire suppressant distribution testing was performed on the Materials Science Research Rack-1 (MSRR-1), a furnace facility payload that will be installed in the U.S. Lab module of the International Space Station. Unlike racks that were tested previously, the MSRR-1 uses the Active Rack Isolation System (ARIS) to reduce vibration on experiments, so the effects of ARIS on fire suppressant distribution were unknown. Two tests were performed to map the distribution of CO2 fire suppressant throughout a mockup of the MSRR-1 designed to have the same component volumes and flowpath restrictions as the flight rack. For the first test, the average maximum CO2 concentration for the rack was 60 percent, achieved within 45 s of discharge initiation, meeting the requirement to reach 50 percent throughout the rack within 1 min. For the second test, one of the experiment mockups was removed to provide a worst-case configuration, and the average maximum CO2 concentration for the rack was 58 percent. Comparing the results of this testing with results from previous testing leads to several general conclusions that can be used to evaluate future racks. The MSRR-1 will meet the requirements for fire suppressant distribution. Primary factors that affect the ability to meet the CO2 distribution requirements are the free air volume in the rack and the total area and distribution of openings in the rack shell. The length of the suppressant flowpath and degree of tortuousness has little correlation with CO2 concentration. The total area of holes in the rack shell could be significantly increased. The free air volume could be significantly increased. To ensure the highest maximum CO2 concentration, the PFE nozzle should be inserted to the stop on the nozzle.

  15. The Intradermal Tuberculin Test as a Research Tool

    African Journals Online (AJOL)

    1973-01-27

    Jan 27, 1973 ... to attend school in the second case, are a few of the factors which can bias the results.) The scientist must ensure that all steps are taken to avoid any .... A random permutation of the 4 digits was matched with the sequential list of numbers. A 'mother list' of. 180 random permutations was easily obtained, ...

  16. A critique of statistical hypothesis testing in clinical research

    Directory of Open Access Journals (Sweden)

    Somik Raha

    2011-01-01

    Full Text Available Many have documented the difficulty of using the current paradigm of Randomized Controlled Trials (RCTs to test and validate the effectiveness of alternative medical systems such as Ayurveda. This paper critiques the applicability of RCTs for all clinical knowledge-seeking endeavors, of which Ayurveda research is a part. This is done by examining statistical hypothesis testing, the underlying foundation of RCTs, from a practical and philosophical perspective. In the philosophical critique, the two main worldviews of probability are that of the Bayesian and the frequentist. The frequentist worldview is a special case of the Bayesian worldview requiring the unrealistic assumptions of knowing nothing about the universe and believing that all observations are unrelated to each other. Many have claimed that the first belief is necessary for science, and this claim is debunked by comparing variations in learning with different prior beliefs. Moving beyond the Bayesian and frequentist worldviews, the notion of hypothesis testing itself is challenged on the grounds that a hypothesis is an unclear distinction, and assigning a probability on an unclear distinction is an exercise that does not lead to clarity of action. This critique is of the theory itself and not any particular application of statistical hypothesis testing. A decision-making frame is proposed as a way of both addressing this critique and transcending ideological debates on probability. An example of a Bayesian decision-making approach is shown as an alternative to statistical hypothesis testing, utilizing data from a past clinical trial that studied the effect of Aspirin on heart attacks in a sample population of doctors. As a big reason for the prevalence of RCTs in academia is legislation requiring it, the ethics of legislating the use of statistical methods for clinical research is also examined.

  17. Aircraft Engine Noise Research and Testing at the NASA Glenn Research Center

    Science.gov (United States)

    Elliott, Dave

    2015-01-01

    The presentation will begin with a brief introduction to the NASA Glenn Research Center as well as an overview of how aircraft engine noise research fits within the organization. Some of the NASA programs and projects with noise content will be covered along with the associated goals of aircraft noise reduction. Topics covered within the noise research being presented will include noise prediction versus experimental results, along with engine fan, jet, and core noise. Details of the acoustic research conducted at NASA Glenn will include the test facilities available, recent test hardware, and data acquisition and analysis methods. Lastly some of the actual noise reduction methods investigated along with their results will be shown.

  18. Cognitive Bias in Systems Verification

    Science.gov (United States)

    Larson, Steve

    2012-01-01

    Working definition of cognitive bias: Patterns by which information is sought and interpreted that can lead to systematic errors in decisions. Cognitive bias is used in diverse fields: Economics, Politics, Intelligence, Marketing, to name a few. Attempts to ground cognitive science in physical characteristics of the cognitive apparatus exceed our knowledge. Studies based on correlations; strict cause and effect is difficult to pinpoint. Effects cited in the paper and discussed here have been replicated many times over, and appear sound. Many biases have been described, but it is still unclear whether they are all distinct. There may only be a handful of fundamental biases, which manifest in various ways. Bias can effect system verification in many ways . Overconfidence -> Questionable decisions to deploy. Availability -> Inability to conceive critical tests. Representativeness -> Overinterpretation of results. Positive Test Strategies -> Confirmation bias. Debiasing at individual level very difficult. The potential effect of bias on the verification process can be managed, but not eliminated. Worth considering at key points in the process.

  19. Simulating Neutronic Core Parameters in a Research and Test Reactor

    International Nuclear Information System (INIS)

    Selim, H.K.; Amin, E.A.; Koutb, M.E.

    2011-01-01

    The present study proposes an Artificial Neural Network (ANN) modeling technique that predicts the control rods positions in a nuclear research reactor. The neutron, flux in the core of the reactor is used as the training data for the neural network model. The data used to train and validate the network are obtained by modeling the reactor core with the neutronic calculation code: CITVAP. The type of the network used in this study is the feed forward multilayer neural network with the backpropagation algorithm. The results show that the proposed ANN has good generalization capability to estimate the control rods positions knowing neutron flux for a research and test reactor. This method can be used to predict critical control rods positions to be used for reactor operation after reload

  20. Operation, test, research and development of the high temperature engineering test reactor (HTTR). FY2003

    International Nuclear Information System (INIS)

    2005-03-01

    The High Temperature Engineering Test Reactor (HTTR) constructed at the Oarai Research Establishment of The Japan Atomic Energy Research Institute (JAERI) is the first high-temperature gas-cooled reactor (HTGR) in Japan, which is a graphite-moderated and helium gas-cooled reactor with 30MW of thermal power. Coolant of helium-gas circulates under the pressure of about 4Mpa, and the reactor inlet and outlet temperature are 395degC and 950degC (maximum), respectively coated particle fuel is used as fuel, and the HTTR core is composed of graphite prismatic blocks. The full power operation of 30MW was attained in December, 2001, and then JAERI received the commissioning license for the HTTR in March, 2002. Since 2002, we have been carrying out rated power operation, safety demonstration tests and several R and Ds, etc., and conducted the high-temperature test operation of 950degC in April, 2004. This report summarizes activities and test results on HTTR operation and maintenance as well as safety demonstration tests and several R and Ds, which were carried out in the fiscal year of 2003 before the high temperature test operation of 950degC. (author)

  1. MAFF sponsored research: detection tests for irradiated food

    International Nuclear Information System (INIS)

    Blackburn, C.M.; Holley, P.A.; Pryke, D.C.

    1993-01-01

    In their 1986 report on the safety and wholesomeness of irradiated food the UK Advisory Committee on Irradiated and Novel Foods (ACINF) recognised that a generally applicable test to determine if a food had been irradiated was not available. The committee considered that, although not a pre-requisite, the existence of a detection test would be a useful supplement to a control system and do much to reassure consumers; with this in mind ACINF recommended that detection methods should be kept under review. As a consequence, in 1987 the Ministry initiated a comprehensive R and D detection test programme. Over fifty papers have been published to date as a result of this programme. MAFF (Ministry Of Agriculture Fisheries and Food) has also been involved in other research associated with irradiation and food safety, some of which is described in this paper. This paper aims to give an overview of recent work funded under the food irradiation programme. Twelve projects have been supported over the last two years, ten of which involved the development of detection tests for irradiated food. A summary of these projects is presented: - Thermoluminescence; - Electron Spin Resonance; - 2-alkylcyclobutanones; -Determination Of Hydrogen; - Differential Scanning Calorimetry; - Limulus Amoebocyte Lysate; - DNA; - Pesticide Breakdown; - Neutron Irradiation; -Future Plans. (orig./vhe)

  2. Reduced enrichment for research and test reactors: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    1993-08-01

    November 9--10, 1978, marked the first of what has become an annual event--the International Meeting on Reduced Enrichment for Research and Test Reactors (RERTR). The meeting brought together for the first time many people who became major program participants in later years. This first meeting emphasized fuel development, and it established the basis for all later meetings. Believing that the proceedings of this first meeting are important as a historical record of the beginning of the international RERTR effort. This report provides presentations and discussions of this original meeting. Individual papers have been cataloged separately.

  3. Improving the proliferation resistance of research and test reactors

    International Nuclear Information System (INIS)

    Lewis, R.A.

    1978-01-01

    Elimination, or substantial reduction, of the trade in unirradiated highly-enriched fuel elements for research and test reactors would significantly reduce the proliferation risk associated with the current potential for diversion of these materials. To this end, it is the long-term goal of U.S. policy to fuel all new and existing research and test reactors with uranium of less-than-20% enrichment (but substantially greater than natural) excepting, perhaps, only a small number of high-power, high-performance, reactors. The U.S. development program for enrichment reduction in research and test reactor designs currently using 90-93% enriched uranium is based on the practical criterion that enrichment reduction should not cause significant flux performance (flux per unit power) or burnup performance degradation relative to the unmodified reactor design. To first order, this implies the requirement that the 235 U loading in the reduced-enrichment fuel elements be the same as the 235 U loading in the 90-93% enriched fuel elements. This can be accomplished by substitution of higher uranium density fuel technology for currently-used fuel technology in the fuel meat volume of the current fuel element design and/or by increasing the usable fuel meat volume. For research and test reactors of power greater than 5-10 megawatts, fuel technology does not currently exist that would permit enrichment reductions to below 20% utilizing this criterion. A program is now beginning in the U.S. to develop the necessary fuel technology. Currently-proven fuel technology is capable, however, of accommodating enrichment reductions to the 30-45% range (from 90-93%) for many reactors in the 5-50MW range. Accordingly the U.S. is proposing to convert existing reactors (and new designs) in the 5-50MW range from the use of highly-enriched fuel to the use of 30-45% enriched fuel, and reactors of less that about 5MW to less-than-20% enrichment, wherever this can be done without significant

  4. Reduced enrichment for research and test reactors: Proceedings

    International Nuclear Information System (INIS)

    1993-08-01

    November 9--10, 1978, marked the first of what has become an annual event--the International Meeting on Reduced Enrichment for Research and Test Reactors (RERTR). The meeting brought together for the first time many people who became major program participants in later years. This first meeting emphasized fuel development, and it established the basis for all later meetings. Believing that the proceedings of this first meeting are important as a historical record of the beginning of the international RERTR effort. This report provides presentations and discussions of this original meeting. Individual papers have been cataloged separately

  5. A review of cognitive biases in youth depression: attention, interpretation and memory.

    Science.gov (United States)

    Platt, Belinda; Waters, Allison M; Schulte-Koerne, Gerd; Engelmann, Lina; Salemink, Elske

    2017-04-01

    Depression is one of the most common mental health problems in childhood and adolescence. Although data consistently show it is associated with self-reported negative cognitive styles, less is known about the mechanisms underlying this relationship. Cognitive biases in attention, interpretation and memory represent plausible mechanisms and are known to characterise adult depression. We provide the first structured review of studies investigating the nature and causal role of cognitive biases in youth depression. Key questions are (i) do cognitive biases characterise youth depression? (ii) are cognitive biases a vulnerability factor for youth depression? and (iii) do cognitive biases play a causal role in youth depression? We find consistent evidence for positive associations between attention and interpretation biases and youth depression. Stronger biases in youth with an elevated risk of depression support cognitive-vulnerability models. Preliminary evidence from cognitive bias modification paradigms supports a causal role of attention and interpretation biases in youth depression but these paradigms require testing in clinical samples before they can be considered treatment tools. Studies of memory biases in youth samples have produced mixed findings and none have investigated the causal role of memory bias. We identify numerous areas for future research in this emerging field.

  6. Faculty Rank System, Research Motivation, and Faculty Research Productivity: Measure Refinement and Theory Testing.

    Science.gov (United States)

    Tien, Flora F.; Blackburn, Robert T.

    1996-01-01

    A study explored the relationship between the traditional system of college faculty rank and faculty research productivity from the perspectives of behavioral reinforcement theory and selection function. Six hypotheses were generated and tested, using data from a 1989 national faculty survey. Results failed to support completely either the…

  7. UAV Research, Operations, and Flight Test at the NASA Dryden Flight Research Center

    Science.gov (United States)

    Cosentino, Gary B.

    2009-01-01

    This slide presentation reviews some of the projects that have extended NASA Dryden's capabilities in designing, testing, and using Unmanned Aerial Vehicles (UAV's). Some of the UAV's have been for Science and experimental applications, some have been for flight research and demonstration purposes, and some have been small UAV's for other customers.

  8. Publishing nutrition research: validity, reliability, and diagnostic test assessment in nutrition-related research.

    Science.gov (United States)

    Gleason, Philip M; Harris, Jeffrey; Sheean, Patricia M; Boushey, Carol J; Bruemmer, Barbara

    2010-03-01

    This is the sixth in a series of monographs on research design and analysis. The purpose of this article is to describe and discuss several concepts related to the measurement of nutrition-related characteristics and outcomes, including validity, reliability, and diagnostic tests. The article reviews the methodologic issues related to capturing the various aspects of a given nutrition measure's reliability, including test-retest, inter-item, and interobserver or inter-rater reliability. Similarly, it covers content validity, indicators of absolute vs relative validity, and internal vs external validity. With respect to diagnostic assessment, the article summarizes the concepts of sensitivity and specificity. The hope is that dietetics practitioners will be able to both use high-quality measures of nutrition concepts in their research and recognize these measures in research completed by others. Copyright 2010 American Dietetic Association. Published by Elsevier Inc. All rights reserved.

  9. Non-animal methodologies within biomedical research and toxicity testing.

    Science.gov (United States)

    Knight, Andrew

    2008-01-01

    Laboratory animal models are limited by scientific constraints on human applicability, and increasing regulatory restrictions, driven by social concerns. Reliance on laboratory animals also incurs marked - and in some cases, prohibitive - logistical challenges, within high-throughput chemical testing programmes, such as those currently underway within Europe and the US. However, a range of non-animal methodologies is available within biomedical research and toxicity testing. These include: mechanisms to enhance the sharing and assessment of existing data prior to conducting further studies, and physicochemical evaluation and computerised modelling, including the use of structure-activity relationships and expert systems. Minimally-sentient animals from lower phylogenetic orders or early developmental vertebral stages may be used, as well as microorganisms and higher plants. A variety of tissue cultures, including immortalised cell lines, embryonic and adult stem cells, and organotypic cultures, are also available. In vitro assays utilising bacterial, yeast, protozoal, mammalian or human cell cultures exist for a wide range of toxic and other endpoints. These may be static or perfused, and may be used individually, or combined within test batteries. Human hepatocyte cultures and metabolic activation systems offer potential assessment of metabolite activity and organ-organ interaction. Microarray technology may allow genetic expression profiling, increasing the speed of toxin detection, well prior to more invasive endpoints. Enhanced human clinical trials utilising micro- dosing, staggered dosing, and more representative study populations and durations, as well as surrogate human tissues, advanced imaging modalities and human epidemiological, sociological and psycho- logical studies, may increase our understanding of illness aetiology and pathogenesis, and facilitate the development of safe and effective pharmacologic interventions. Particularly when human tissues

  10. Bias Within

    Directory of Open Access Journals (Sweden)

    Marla B. Hall

    2015-03-01

    Full Text Available Breast cancer mortality has affected African American women at a disproportionate rate. The purpose of this research was to assess how health professionals’ cultural competence contributes to African American women’s barriers to and receipt of mammograms. Sixty-one African American women residing in Harris County, Texas, shared their views within a series of focus groups. Theoretical propositions from the PEN-3 model were used to understand mammography adherence at the interpersonal level. Participants noted various perceived factors associated with mammography incompliance. Lack of professionalism of clinicians and clerical staff contributed to a decrease in health care services utilization. In addition, cultural insensitivity and discriminatory behavior enabled an attitude of medical mistrust. Improving patient–provider communication, through culturally appropriate centered educational efforts, is a beneficial strategy for breast health programs among underserved populations.

  11. Research on the Test of Transmission Line Galloping

    Science.gov (United States)

    Zhang, Lichun; Li, Qing; lv, Zhongbin; Ji, Kunpeng; Liu, Bin

    2018-03-01

    The load of iced transmission line and the load generated by galloping after the conductor are covered by ice all may cause severe circuit faults, such as tripping, conductor breaking, armor clamp damage and even tower collapse, thus severely threatening running safety of power system. The generation and development processes of galloping of power transmission line is very complicated, and numerous factors may influence the galloping excitation, such as environmental factors, terrain factors and structural parameters of power transmission line; in which, the ice covering of conductor is one of necessary factors causing galloping. Therefore, researches on ice covering increasing test of different types of conductors under different meteorological conditions have been conducted in large-sized multi-functional phytotron, thus obtaining the relation curve of ice covering increasing of conductor along with time under different conditions, and analyzing factors influencing increasing of ice covering. The research result shows that under the same ice covering conditions, the increasing of ice covering of conductor with small diameter is relatively rapid; both environmental temperature and wind speed have obvious influence on increasing of ice covering of conductor, and the environmental temperature will decide the type of ice covering of conductor surface. Meanwhile, after wind tunnel tests targeting conductors with different ice covering shapes, pneumatic stability loss characteristics of conductors with different ice shapes have been obtained. Research results have important scientific reference value for revealing the mechanism of galloping of iced power transmission line, and have relatively high engineering practicability value for promoting realization of early warning system for galloping of iced power transmission line.

  12. Room 209 excavation response test in the underground research laboratory

    International Nuclear Information System (INIS)

    Lang, P.A.

    1989-01-01

    An in situ excavation response test was conducted at the Canadian Underground Research Laboratory (URL) in conjunction with excavation of a tunnel (Room 209) through a near-vertical water-bearing fracture oriented perpendicular to the tunnel axis. Encountering a fracture with such desirable characteristics provided a unique opportunity during construction of the URL to try out instrumentation and analytical methods for use in the Excavation Response Experiment (ERE) planned as one of the major URL experiments. The test has produced a valuable data set for validating numerical models. Four modelling groups predicted the response that would be monitored by the instruments. The predictions of the mechanical response were generally good. However, the predictions of the permeability and hydraulic pressure changes in the fracture, and the water flows into the tunnel, were poor. It is concluded that we may not understand the mechanisms that occur in the fracture in response to excavation. Laboratory testing, and development of a contracting joint code, has been initiated to further investigate this phenomenon. Preliminary results indicate that the excavation damaged zone in the walls and crown is less than 0.5 m thick and has relatively low permeability. The damaged zone in the floor is at least 1 m thick and has relatively high permeability. The damage in the floor could be reduced in future excavations by using controlled blasting methods similar to those used for the walls and crown

  13. Nevada Test Site-Directed Research, Development, and Demonstration

    International Nuclear Information System (INIS)

    Will Lewis, Compiler

    2006-01-01

    The Nevada Test Site-Directed Research, Development, and Demonstration (SDRD) program completed a very successful year of research and development activities in FY 2005. Fifty new projects were selected for funding this year, and five FY 2004 projects were brought to conclusion. The total funds expended by the SDRD program were $5.4 million, for an average per project cost of just under $100,000. Two external audits of SDRD accounting practices were conducted in FY 2005. Both audits found the program's accounting practices consistent with the requirements of DOE Order 413.2A, and one included the observation that the NTS contractor ''did an exceptional job in planning and executing year-start activities.'' Highlights for the year included: the filing of 18 invention disclosures for intellectual property generated by FY 2005 projects; programmatic adoption of 17 FY 2004 SDRD-developed technologies; participation in the tri-lab Laboratory Directed Research and Development (LDRD) and SDRD program review that was broadly attended by NTS, NNSA, LDRD, and U.S. Department of Homeland Security representatives; peer reviews of all FY 2005 projects; and the successful completion of 55 R and D projects, as presented in this report

  14. Operation, test, research and development of the high temperature engineering test reactor (HTTR). (FY2005)

    International Nuclear Information System (INIS)

    2007-03-01

    The High Temperature Engineering Test Reactor (HTTR) constructed at the Oarai Research and Development Center of the Japan Atomic Energy Agency (JAEA) is the first high-temperature gas-cooled reactor (HTGR) in Japan, which is a graphite-moderated and helium gas-cooled reactor with 30 MW of thermal power. The full power operation of 30 MW was attained in December, 2001, and then JAERI (JAEA) received the commissioning license for the HTTR in March, 2002. Since 2002, we have been carrying out rated power operation, safety demonstration tests and several R and Ds, etc., and conducted the high-temperature test operation of 950degC in April, 2004. In fiscal 2005 year, periodical inspection and overhaul of reactivity control system were conducted, and safety demonstration tests were promoted. This report summarizes activities and test results on HTTR operation and maintenance as well as safety demonstration tests and several R and Ds, which were carried out in the fiscal year of 2005. (author)

  15. Transportable Heavy Duty Emissions Testing Laboratory and Research Program

    Energy Technology Data Exchange (ETDEWEB)

    David Lyons

    2008-03-31

    The objective of this program was to quantify the emissions from heavy-duty vehicles operating on alternative fuels or advanced fuel blends, often with novel engine technology or aftertreatment. In the first year of the program West Virginia University (WVU) researchers determined that a transportable chassis dynamometer emissions measurement approach was required so that fleets of trucks and buses did not need to be ferried across the nation to a fixed facility. A Transportable Heavy-Duty Vehicle Emissions Testing Laboratory (Translab) was designed, constructed and verified. This laboratory consisted of a chassis dynamometer semi-trailer and an analytic trailer housing a full scale exhaust dilution tunnel and sampling system which mimicked closely the system described in the Code of Federal Regulations for engine certification. The Translab was first used to quantify emissions from natural gas and methanol fueled transit buses, and a second Translab unit was constructed to satisfy research demand. Subsequent emissions measurement was performed on trucks and buses using ethanol, Fischer-Tropsch fuel, and biodiesel. A medium-duty chassis dynamometer was also designed and constructed to facilitate research on delivery vehicles in the 10,000 to 20,000lb range. The Translab participated in major programs to evaluate low-sulfur diesel in conjunction with passively regenerating exhaust particulate filtration technology, and substantial reductions in particulate matter were recorded. The researchers also participated in programs to evaluate emissions from advanced natural gas engines with closed loop feedback control. These natural gas engines showed substantially reduced levels of oxides of nitrogen. For all of the trucks and buses characterized, the levels of carbon monoxide, oxides of nitrogen, hydrocarbons, carbon dioxide and particulate matter were quantified, and in many cases non-regulated species such as aldehydes were also sampled. Particle size was also

  16. New biological research and understanding of Papanicolaou's test.

    Science.gov (United States)

    Smith, Elizabeth R; George, Sophia H; Kobetz, Erin; Xu, Xiang-Xi

    2018-06-01

    The development of the Papanicolaou smear test by Dr. George Nicholas Papanicolaou (1883-1962) is one of the most significant achievements in screening for disease and cancer prevention in history. The Papanicolaou smear has been used for screening of cervical cancer since the 1950s. The test is technically straightforward and practical and based on a simple scientific observation: malignant cells have an aberrant nuclear morphology that can be distinguished from benign cells. Here, we review the scientific understanding that has been achieved and continues to be made on the causes and consequences of abnormal nuclear morphology, the basis of Dr. Papanicolaou's invention. The deformed nuclear shape is caused by the loss of lamina and nuclear envelope structural proteins. The consequences of a nuclear envelope defect include chromosomal numerical instability, altered chromatin organization and gene expression, and increased cell mobility because of a malleable nuclear envelope. HPV (Human Papilloma Virus) infection is recognized as the key etiology in the development of cervical cancer. Persistent HPV infection causes disruption of the nuclear lamina, which presents as a change in nuclear morphology detectable by a Papanicolaou smear. Thus, the causes and consequences of nuclear deformation are now linked to the mechanisms of viral carcinogenesis, and are still undergoing active investigation to reveal the details. Recently a statue was installed in front of the Papanicolaou's Cancer Research Building to honor the inventor. Remarkably, the invention nearly 60 years ago by Dr. Papanicolaou still exerts clinical impacts and inspires scientific inquiries. © 2018 Wiley Periodicals, Inc.

  17. Brookhaven National Laboratory's Accelerator Test Facility: research highlights and plans

    Science.gov (United States)

    Pogorelsky, I. V.; Ben-Zvi, I.

    2014-08-01

    The Accelerator Test Facility (ATF) at Brookhaven National Laboratory has served as a user facility for accelerator science for over a quarter of a century. In fulfilling this mission, the ATF offers the unique combination of a high-brightness 80 MeV electron beam that is synchronized to a 1 TW picosecond CO2 laser. We unveil herein our plan to considerably expand the ATF's floor space with an upgrade of the electron beam's energy to 300 MeV and the CO2 laser's peak power to 100 TW. This upgrade will propel the ATF even further to the forefront of research on advanced accelerators and radiation sources, supporting the most innovative ideas in this field. We discuss emerging opportunities for scientific breakthroughs, including the following: plasma wakefield acceleration studies in research directions already active at the ATF; laser wakefield acceleration (LWFA), where the longer laser wavelengths are expected to engender a proportional increase in the beam's charge while our linac will assure, for the first time, the opportunity to undertake detailed studies of seeding and staging of the LWFA; proton acceleration to the 100-200 MeV level, which is essential for medical applications; and others.

  18. 27 CFR 25.196 - Removals for research, development or testing.

    Science.gov (United States)

    2010-04-01

    ... Analysis, Research, Development Or Testing § 25.196 Removals for research, development or testing. (a) A brewer may remove beer, without payment of tax, for use in research, development, or testing (other than... or brewery operations. Beer may be removed for research, development or testing in packages or in...

  19. Allen Newell's Program of Research: The Video-Game Test.

    Science.gov (United States)

    Gobet, Fernand

    2017-04-01

    Newell (1973) argued that progress in psychology was slow because research focused on experiments trying to answer binary questions, such as serial versus parallel processing. In addition, not enough attention was paid to the strategies used by participants, and there was a lack of theories implemented as computer models offering sufficient precision for being tested rigorously. He proposed a three-headed research program: to develop computational models able to carry out the task they aimed to explain; to study one complex task in detail, such as chess; and to build computational models that can account for multiple tasks. This article assesses the extent to which the papers in this issue advance Newell's program. While half of the papers devote much attention to strategies, several papers still average across them, a capital sin according to Newell. The three courses of action he proposed were not popular in these papers: Only two papers used computational models, with no model being both able to carry out the task and to account for human data; there was no systematic analysis of a specific video game; and no paper proposed a computational model accounting for human data in several tasks. It is concluded that, while they use sophisticated methods of analysis and discuss interesting results, overall these papers contribute only little to Newell's program of research. In this respect, they reflect the current state of psychology and cognitive science. This is a shame, as Newell's ideas might help address the current crisis of lack of replication and fraud in psychology. Copyright © 2017 The Author. Topics in Cognitive Science published by Wiley Periodicals, Inc. on behalf of Cognitive Science Society.

  20. Basic research on high-uranium density fuels for research and test reactors

    International Nuclear Information System (INIS)

    Ugajin, M.; Itoh, A.; Akabori, M.

    1992-01-01

    High-uranium density fuels, uranium silicides (U 3 Si 2 , U 3 Si) and U 6 Me-type uranium alloys (Me = Fe, Mn, Ni), were prepared and examined metallurgically as low-enriched uranium (LEU) fuels for research and test reactors. Miniature aluminum-dispersion plate-type fuel (miniplate) and aluminum-clad disk-type fuel specimens were fabricated and subjected to the neutron irradiation in JMTR (Japan Materials Testing Reactor). Fuel-aluminum compatibility tests were conducted to elucidate the extent of reaction and to identify reaction products. The relative stability of the fuels in an aluminum matrix was established at 350degC or above. Experiments were also performed to predict the chemical form of the solid fission-products in the uranium silicide (U 3 Si 2 ) simulating a high burnup anticipated for reactor service. (author)

  1. Bias During the Evaluation of Animal Studies?

    Science.gov (United States)

    Knight, Andrew

    2012-02-23

    My recent book entitled The Costs and Benefits of Animal Experiments seeks to answer a key question within animal ethics, namely: is animal experimentation ethically justifiable? Or, more precisely, is it justifiable within the utilitarian cost:benefit framework that fundamentally underpins most regulations governing animal experimentation? To answer this question I reviewed more than 500 scientific publications describing animal studies, animal welfare impacts, and alternative research, toxicity testing and educational methodologies. To minimise bias I focused primarily on large-scale systematic reviews that had examined the human clinical and toxicological utility of animal studies. Despite this, Dr. Susanne Prankel recently reviewed my book in this journal, essentially accusing me of bias. However, she failed to provide any substantive evidence to refute my conclusions, let alone evidence of similar weight to that on which they are based. Those conclusions are, in fact, firmly based on utilitarian ethical reasoning, informed by scientific evidence of considerable strength, and I believe they are robust.

  2. An inclusive taxonomy of behavioral biases

    Directory of Open Access Journals (Sweden)

    David Peón

    2017-07-01

    Full Text Available This paper overviews the theoretical and empirical research on behavioral biases and their influence in the literature. To provide a systematic exposition, we present a unified framework that takes the reader through an original taxonomy, based on the reviews of relevant authors in the field. In particular, we establish three broad categories that may be distinguished: heuristics and biases; choices, values and frames; and social factors. We then describe the main biases within each category, and revise the main theoretical and empirical developments, linking each bias with other biases and anomalies that are related to them, according to the literature.

  3. Obesity, the endocannabinoid system, and bias arising from pharmaceutical sponsorship.

    Directory of Open Access Journals (Sweden)

    John M McPartland

    Full Text Available Previous research has shown that academic physicians conflicted by funding from the pharmaceutical industry have corrupted evidence based medicine and helped enlarge the market for drugs. Physicians made pharmaceutical-friendly statements, engaged in disease mongering, and signed biased review articles ghost-authored by corporate employees. This paper tested the hypothesis that bias affects review articles regarding rimonabant, an anti-obesity drug that blocks the central cannabinoid receptor.A MEDLINE search was performed for rimonabant review articles, limited to articles authored by USA physicians who served as consultants for the company that manufactures rimonabant. Extracted articles were examined for industry-friendly bias, identified by three methods: analysis with a validated instrument for monitoring bias in continuing medical education (CME; analysis for bias defined as statements that ran contrary to external evidence; and a tally of misrepresentations about the endocannabinoid system. Eight review articles were identified, but only three disclosed authors' financial conflicts of interest, despite easily accessible information to the contrary. The Takhar CME bias instrument demonstrated statistically significant bias in all the review articles. Biased statements that were nearly identical reappeared in the articles, including disease mongering, exaggerating rimonabant's efficacy and safety, lack of criticisms regarding rimonabant clinical trials, and speculations about surrogate markers stated as facts. Distinctive and identical misrepresentations regarding the endocannabinoid system also reappeared in articles by different authors.The findings are characteristic of bias that arises from financial conflicts of interest, and suggestive of ghostwriting by a common author. Resolutions for this scenario are proposed.

  4. Forecaster Behaviour and Bias in Macroeconomic Forecasts

    OpenAIRE

    Roy Batchelor

    2007-01-01

    This paper documents the presence of systematic bias in the real GDP and inflation forecasts of private sector forecasters in the G7 economies in the years 1990–2005. The data come from the monthly Consensus Economics forecasting service, and bias is measured and tested for significance using parametric fixed effect panel regressions and nonparametric tests on accuracy ranks. We examine patterns across countries and forecasters to establish whether the bias reflects the inefficient use of i...

  5. Operation, test, research and development of the High Temperature Engineering Test Reactor (HTTR). FY2013

    International Nuclear Information System (INIS)

    2014-12-01

    The High Temperature Engineering Test Reactor (HTTR), a graphite-moderated and helium gas-cooled reactor with 30MW of thermal power, constructed at the Oarai Research and Development Center of the Japan Atomic Energy Agency (JAEA) is the first high-temperature gas-cooled reactor (HTGR) in Japan. The HTTR was attained at the full power operation of 30MW in December 2001 and achieved the 950degC of outlet coolant temperature at the outside the reactor pressure vessel in June 2004. To establish and upgrade basic technologies for HTGRs, we have obtained demonstration test data necessary for several R and Ds, and accumulated operation and maintenance experience of HTGRs throughout the HTTR's operation such as rated power operations, safety demonstration tests and long-term high temperature operations, and so on. In fiscal year 2013, we started to prepare the application document of reactor installation license for the HTTR to prove conformity with the new research reactor's safety regulatory requirements taken effect from December 2013. We had been making effort to restart the HTTR which was stopped since the 2011 when the Pacific coast of Tohoku Earthquake (2011.3.11) occurred. This report summarizes activities and results of HTTR operation, maintenance, and several R and Ds, which were carried out in the fiscal year 2013. (author)

  6. Operation, test, research and development of the High Temperature Engineering Test Reactor (HTTR). FY2014

    International Nuclear Information System (INIS)

    2016-02-01

    The High Temperature Engineering Test Reactor (HTTR), a graphite-moderated and helium gas-cooled reactor with 30 MW of thermal power, constructed at the Oarai Research and Development Center of the Japan Atomic Energy Agency is the first high-temperature gas-cooled reactor (HTGR) in Japan. The HTTR was attained at the full power operation of 30 MW in December 2001 and achieved the 950degC of coolant outlet temperature at outside of the reactor pressure vessel in June 2004. To establish and upgrade basic technologies for HTGRs, we have obtained demonstration test data necessary for several R and Ds, and accumulated operation and maintenance experience of HTGRs throughout the HTTR's operation such as rated power operations, safety demonstration tests and long-term high temperature operations, and so on. In fiscal year 2014, we started to apply the application document of reactor installation license for the HTTR to prove conformity with the new research reactor's safety regulatory requirements taken effect from December 2013. We had been making effort to restart the HTTR which was stopped since the 2011 by the Pacific coast of Tohoku Earthquake. This report summarizes activities and results of HTTR operation, maintenance, and several R and Ds, which were carried out in the fiscal year 2014. (author)

  7. Material test reactor fuel research at the BR2 reactor

    Energy Technology Data Exchange (ETDEWEB)

    Dyck, Steven Van; Koonen, Edgar; Berghe, Sven van den [Institute for Nuclear Materials Science, SCK-CEN, Boeretang, Mol (Belgium)

    2012-03-15

    The construction of new, high performance material test reactor or the conversion of such reactors' core from high enriched uranium (HEU) to low enriched uranium (LEU) based fuel requires several fuel qualification steps. For the conversion of high performance reactors, high density dispersion or monolithic fuel types are being developed. The Uranium-Molybdenum fuel system has been selected as reference system for the qualification of LEU fuels. For reactors with lower performance characteristics, or as medium enriched fuel for high performance reactors, uranium silicide dispersion fuel is applied. However, on the longer term, the U-Mo based fuel types may offer a more efficient fuel alternative and-or an easier back-end solution with respect to the silicide based fuels. At the BR2 reactor of the Belgian nuclear research center, SCK-CEN in Mol, several types of fuel testing opportunities are present to contribute to such qualification process. A generic validation test for a selected fuel system is the irradiation of flat plates with representative dimensions for a fuel element. By flexible positioning and core loading, bounding irradiation conditions for fuel elements can be performed in a standard device in the BR2. For fuel element designs with curved plates, the element fabrication method compatibility of the fuel type can be addressed by incorporating a set of prototype fuel plates in a mixed driver fuel element of the BR2 reactor. These generic types of tests are performed directly in the primary coolant flow conditions of the BR2 reactor. The experiment control and interpretation is supported by detailed neutronic and thermal-hydraulic modeling of the experiments. Finally, the BR2 reactor offers the flexibility for irradiation of full size prototype fuel elements, as 200mm diameter irradiation channels are available. These channels allow the accommodation of various types of prototype fuel elements, eventually using a dedicated cooling loop to provide the

  8. Fuel tank integrity research : fuel tank analyses and test plans

    Science.gov (United States)

    2013-04-15

    The Federal Railroad Administrations Office of Research : and Development is conducting research into fuel tank : crashworthiness. Fuel tank research is being performed to : determine strategies for increasing the fuel tank impact : resistance to ...

  9. Outline of the results of test and research at expense of entrusting research on atomic energy peaceful utilization, 1980

    International Nuclear Information System (INIS)

    1982-03-01

    The test research on the substances promoting the recovery from radiation injuries, the research on the security of the facilities using radioisotopes in earthquakes, the test research on the distribution and behavior of radioactive nuclides in environment for the evaluation of exposure dose, the test research on the rate of scattering of RIs, the measurement and dose evaluation of gaseous radioactive nuclides, the research on the measuring techniques for medium and high concentration gaseous tritium, the test research on the evaluation of the effect of low dose radiation on living things, the epidemiological research on low dose effect, the research on the genetic safety of irradiated foods, the test research on the development of radiation sensitizers to cancer cells, the research on the automation and acceleration of the production of short life RI-labeled compounds, the test research on the safety of high performance air filters for nuclear fuel facilities, the test research on the evaluation of the impact properties of nuclear fuel-transporting casks loaded on vehicles, the research on the application of improved security measures to large scale reprocessing facilities, and the test research on the protection capability of countercollision structures for nuclear ships are outlined. (Kako, I.)

  10. Combination of biased forecasts: Bias correction or bias based weights?

    OpenAIRE

    Wenzel, Thomas

    1999-01-01

    Most of the literature on combination of forecasts deals with the assumption of unbiased individual forecasts. Here, we consider the case of biased forecasts and discuss two different combination techniques resulting in an unbiased forecast. On the one hand we correct the individual forecasts, and on the other we calculate bias based weights. A simulation study gives some insight in the situations where we should use the different methods.

  11. When Left Means Right: An Explanation of the Left Cradling Bias in Terms of Right Hemisphere Specializations

    Science.gov (United States)

    Bourne, Victoria J.; Todd, Brenda K.

    2004-01-01

    Previous research has indicated that 70-85% of women and girls show a bias to hold infants, or dolls, to the left side of their body. This bias is not matched in males (e.g. deChateau, Holmberg & Winberg, 1978; Todd, 1995). This study tests an explanation of cradling preferences in terms of hemispheric specialization for the perception of facial…

  12. Safety analysis calculations for research and test reactors

    Energy Technology Data Exchange (ETDEWEB)

    Chen, S Y; MacDonald, R; MacFarlane, D [Argonne National Laboratory, Argonne, IL (United States)

    1983-08-01

    The goal of the RERTR (Reduced Enrichment in Research and Test Reactor) Program at ANL is to provide technical means for conversion of research and test reactors from HEU (High-Enrichment Uranium) to LEU (Low-Enrichment Uranium) fuels. In exploring the feasibility of conversion, safety considerations are a prime concern; therefore, safety analyses must be performed for reactors undergoing the conversion. This requires thorough knowledge of the important safety parameters for different types of reactors for both HEU and LEU fuel. Appropriate computer codes are needed to predict transient reactor behavior under postulated accident conditions. In this discussion, safety issues for the two general types of reactors i.e., the plate-type (MTR-type) reactor and the rod-type (TRIGA-type) reactor, resulting from the changes associated with LEU vs. HEU fuels, are explored. The plate-type fuels are typically uranium aluminide (UAl{sub x}) compounds dispersed in aluminum and clad with aluminum. Moderation is provided by the water coolant. Self shut-down reactivity coefficients with EU fuel are entirely a result of coolant heating, whereas with LEU fuel there is an additional shut down contribution provided by the direct heating of the fuel due to the Doppler coefficient. In contrast, the rod-type (TRIGA) fuels are mixtures of zirconium hydride, uranium, and erbium. This fuel mixture is formed into rods ( {approx} 1 cm diameter) and clad with stainless steel or Incoloy. In the TRIGA fuel the self-shutdown reactivity is more complex, depending on heating of the fuel rather than the coolant. The two most important mechanisms in providing this feedback are: spectral hardening due to neutron interaction with the ZrH moderator as it is heated and Doppler broadening of resonances in erbium and U-238. Since these phenomena result directly from heating of the fuel, and do not depend on heat transfer to the moderator/coolant, the coefficients are prompt acting. Results of transient

  13. The RERTR [Reduced Enrichment Research and Test Reactor] program:

    International Nuclear Information System (INIS)

    Travelli, A.

    1987-01-01

    The progress of the Reduced Enrichment Research and Test Reactor (RERTR) program is described. After a brief summary of the results which the RERTR program, in collaboration with its many international partners, had achieved by the end of 1986, the activities, results and new developments which ocurred in 1987 are reviewed. Irradiation of the second miniplate series, concentrating on U 3 Si 2 -Al and U 3 Si-Al fuels was completed and postirradiation examinations were performed on many of its miniplates. The whole-core ORR demonstration with U 3 Si 2 -Al fuel at 4.8 g U/cm 3 was completed at the end of March with excellent results and with 29 elements estimated to have reached at least 40 % average burnup. Good progress was made in the area of LEU usage for the production of fission 99 Mo, and in the coordination of safety evaluations related to LEU conversions of U.S. university reactors. Planned activities include testing and demonstrating advanced fuels intended to allow use of reduced enrichment uranium in very-high-performance reactors. Two candidate fuels are U 3 Si-Al with 19.75 % enrichment and U 3 Si 2 -Al with 45 % enrichment. Demonstration of these fuels will include irradiation of full-size elements and, possibly, a full-core demonstration. Achievement of the final program goals is still projected for 1990. This progress could not have been possible without the close international cooperation which has existed from the beginning, and which is essential to the ultimate success of the RERTR program. (Author)

  14. Safety re-assessment of AECL test and research reactors

    International Nuclear Information System (INIS)

    Winfield, D.J.

    1990-01-01

    Atomic Energy of Canada Limited currently has four operating engineering test/research reactors of various sizes and ages; a new isotope-production reactor Maple-X10, under construction at Chalk River Nuclear Laboratories (CRNL), and a heating demonstration reactor, SDR, undergoing high-power commissioning at Whiteshell Nuclear Research Establishment (WNRE). The company is also performing design studies of small reactors for hot water and electricity production. The older reactors are ZED-2, PTR, NRX, and NRU; these range in age from 42 years (NRX) to 29 years (ZED-2). Since 1984, limited-scope safety re-assessments have been underway on three of these reactors (ZED-2, NRX AND NRU). ZED-2 and PTR are operated by the Reactor Physics Branch; all other reactors are operated by the respective site Reactor Operations Branches. For the older reactors the original safety reports produced were entirely deterministic in nature and based on the design-basis accident concept. The limited scope safety re-assessments for these older reactors, carried out over the past 5 years, have comprised both quantitative probabilistic safety-assessment techniques, such as event tree and fault analysis, and/or qualitative techniques, such as failure mode and effect analysis. The technique used for an individual assessment was dependent upon the specific scope required. This paper discusses the types of analyses carried out, specific insights/recommendations resulting from the analysis, and the plan for future analysis. In addition, during the last four years safety assessments have been carried out on the new isotope-, heat-, and electricity-producing reactors, as part of the safety design review, commissioning and licensing activities

  15. The use of human cells in biomedical research and testing.

    Science.gov (United States)

    Combes, Robert D

    2004-06-01

    The ability to use human cells in biomedical research and testing has the obvious advantage over the use of laboratory animals that the need for species extrapolation is obviated, due to the presence of more-relevant morphological, physiological and biochemical properties, including receptors. Moreover, human cells exhibit the same advantages as animal cells in culture in that different cell types can be used, from different tissues, with a wide range of techniques, to investigate a wide variety of biological phenomena in tissue culture. Human cells can also be grown as organotypic cultures to facilitate the extrapolation from cells to whole organisms. Human cell lines have been available for many years on an ad hoc basis from individual researchers, and also from recognised sources, such as the European Collection of Animal Cell Cultures (ECACC) and, in the USA, the Human Cell Culture Centre (HCCC). Such cells have usually been derived from tumours and this has restricted the variety of types of cells available. This problem has been addressed by using primary human cells that can be obtained from a variety of sources, such as cadavers, diseased tissue, skin strips, peripheral blood, buccal cavity smears, hair follicles and surgical waste from biopsy material that is unsuitable for transplantation purposes. However, primary human cells need to be obtained, processed, distributed and handled in a safe and ethical manner. They also have to be made available at the correct time to researchers very shortly after they become available. It is only comparatively recently that the safe and controlled acquisition of surgical waste and non-transplantable human tissues has become feasible with the establishment of several human tissue banks. Recently, the formation of a UK and European centralised network for human tissue supply has been initiated. The problems of short longevity and loss of specialisation in culture are being approached by: a) cell immortalisation to

  16. Alternatives to animal testing: research, trends, validation, regulatory acceptance.

    Science.gov (United States)

    Huggins, Jane

    2003-01-01

    Current trends and issues in the development of alternatives to the use of animals in biomedical experimentation are discussed in this position paper. Eight topics are considered and include refinement of acute toxicity assays; eye corrosion/irritation alternatives; skin corrosion/irritation alternatives; contact sensitization alternatives; developmental/reproductive testing alternatives; genetic engineering (transgenic) assays; toxicogenomics; and validation of alternative methods. The discussion of refinement of acute toxicity assays is focused primarily on developments with regard to reduction of the number of animals used in the LD(50) assay. However, the substitution of humane endpoints such as clinical signs of toxicity for lethality in these assays is also evaluated. Alternative assays for eye corrosion/irritation as well as those for skin corrosion/irritation are described with particular attention paid to the outcomes, both successful and unsuccessful, of several validation efforts. Alternative assays for contact sensitization and developmental/reproductive toxicity are presented as examples of methods designed for the examination of interactions between toxins and somewhat more complex physiological systems. Moreover, genetic engineering and toxicogenomics are discussed with an eye toward the future of biological experimentation in general. The implications of gene manipulation for research animals, specifically, are also examined. Finally, validation methods are investigated as to their effectiveness, or lack thereof, and suggestions for their standardization and improvement, as well as implementation are reviewed.

  17. Research of the ultrasonic testing parts reconditioned by welding

    Directory of Open Access Journals (Sweden)

    C. Petriceanu

    2016-07-01

    Full Text Available The paper presents the results obtained following the nondestructive ultrasonic testing of crankpin shaft of a crankshaft that were reconditioned by welding. After the ultrasonic testing, the reconditioned samples were cut and subjected to visual testing and microstructure examination. When the results obtained following the nondestructive tests were analyzed, it was observed that the ultrasonic nondestructive testing method is an efficient way to determine the conformity of the areas that were reconditioned by welding.

  18. Mapping species distributions with MAXENT using a geographically biased sample of presence data: a performance assessment of methods for correcting sampling bias.

    Science.gov (United States)

    Fourcade, Yoan; Engler, Jan O; Rödder, Dennis; Secondi, Jean

    2014-01-01

    MAXENT is now a common species distribution modeling (SDM) tool used by conservation practitioners for predicting the distribution of a species from a set of records and environmental predictors. However, datasets of species occurrence used to train the model are often biased in the geographical space because of unequal sampling effort across the study area. This bias may be a source of strong inaccuracy in the resulting model and could lead to incorrect predictions. Although a number of sampling bias correction methods have been proposed, there is no consensual guideline to account for it. We compared here the performance of five methods of bias correction on three datasets of species occurrence: one "virtual" derived from a land cover map, and two actual datasets for a turtle (Chrysemys picta) and a salamander (Plethodon cylindraceus). We subjected these datasets to four types of sampling biases corresponding to potential types of empirical biases. We applied five correction methods to the biased samples and compared the outputs of distribution models to unbiased datasets to assess the overall correction performance of each method. The results revealed that the ability of methods to correct the initial sampling bias varied greatly depending on bias type, bias intensity and species. However, the simple systematic sampling of records consistently ranked among the best performing across the range of conditions tested, whereas other methods performed more poorly in most cases. The strong effect of initial conditions on correction performance highlights the need for further research to develop a step-by-step guideline to account for sampling bias. However, this method seems to be the most efficient in correcting sampling bias and should be advised in most cases.

  19. 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, H.; van Goor, A.

    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

  20. Examining Event-Related Potential (ERP) correlates of decision bias in recognition memory judgments.

    Science.gov (United States)

    Hill, Holger; Windmann, Sabine

    2014-01-01

    Memory judgments can be based on accurate memory information or on decision bias (the tendency to report that an event is part of episodic memory when one is in fact unsure). Event related potentials (ERP) correlates are important research tools for elucidating the dynamics underlying memory judgments but so far have been established only for investigations of accurate old/new discrimination. To identify the ERP correlates of bias, and observe how these interact with ERP correlates of memory, we conducted three experiments that manipulated decision bias within participants via instructions during recognition memory tests while their ERPs were recorded. In Experiment 1, the bias manipulation was performed between blocks of trials (automatized bias) and compared to trial-by-trial shifts of bias in accord with an external cue (flexibly controlled bias). In Experiment 2, the bias manipulation was performed at two different levels of accurate old/new discrimination as the memory strength of old (studied) items was varied. In Experiment 3, the bias manipulation was added to another, bottom-up driven manipulation of bias induced via familiarity. In the first two Experiments, and in the low familiarity condition of Experiment 3, we found evidence of an early frontocentral ERP component at 320 ms poststimulus (the FN320) that was sensitive to the manipulation of bias via instruction, with more negative amplitudes indexing more liberal bias. By contrast, later during the trial (500-700 ms poststimulus), bias effects interacted with old/new effects across all three experiments. Results suggest that the decision criterion is typically activated early during recognition memory trials, and is integrated with retrieved memory signals and task-specific processing demands later during the trial. More generally, the findings demonstrate how ERPs can help to specify the dynamics of recognition memory processes under top-down and bottom-up controlled retrieval conditions.

  1. Examining Event-Related Potential (ERP) Correlates of Decision Bias in Recognition Memory Judgments

    Science.gov (United States)

    Hill, Holger; Windmann, Sabine

    2014-01-01

    Memory judgments can be based on accurate memory information or on decision bias (the tendency to report that an event is part of episodic memory when one is in fact unsure). Event related potentials (ERP) correlates are important research tools for elucidating the dynamics underlying memory judgments but so far have been established only for investigations of accurate old/new discrimination. To identify the ERP correlates of bias, and observe how these interact with ERP correlates of memory, we conducted three experiments that manipulated decision bias within participants via instructions during recognition memory tests while their ERPs were recorded. In Experiment 1, the bias manipulation was performed between blocks of trials (automatized bias) and compared to trial-by-trial shifts of bias in accord with an external cue (flexibly controlled bias). In Experiment 2, the bias manipulation was performed at two different levels of accurate old/new discrimination as the memory strength of old (studied) items was varied. In Experiment 3, the bias manipulation was added to another, bottom-up driven manipulation of bias induced via familiarity. In the first two Experiments, and in the low familiarity condition of Experiment 3, we found evidence of an early frontocentral ERP component at 320 ms poststimulus (the FN320) that was sensitive to the manipulation of bias via instruction, with more negative amplitudes indexing more liberal bias. By contrast, later during the trial (500–700 ms poststimulus), bias effects interacted with old/new effects across all three experiments. Results suggest that the decision criterion is typically activated early during recognition memory trials, and is integrated with retrieved memory signals and task-specific processing demands later during the trial. More generally, the findings demonstrate how ERPs can help to specify the dynamics of recognition memory processes under top-down and bottom-up controlled retrieval conditions. PMID

  2. Examining Event-Related Potential (ERP correlates of decision bias in recognition memory judgments.

    Directory of Open Access Journals (Sweden)

    Holger Hill

    Full Text Available Memory judgments can be based on accurate memory information or on decision bias (the tendency to report that an event is part of episodic memory when one is in fact unsure. Event related potentials (ERP correlates are important research tools for elucidating the dynamics underlying memory judgments but so far have been established only for investigations of accurate old/new discrimination. To identify the ERP correlates of bias, and observe how these interact with ERP correlates of memory, we conducted three experiments that manipulated decision bias within participants via instructions during recognition memory tests while their ERPs were recorded. In Experiment 1, the bias manipulation was performed between blocks of trials (automatized bias and compared to trial-by-trial shifts of bias in accord with an external cue (flexibly controlled bias. In Experiment 2, the bias manipulation was performed at two different levels of accurate old/new discrimination as the memory strength of old (studied items was varied. In Experiment 3, the bias manipulation was added to another, bottom-up driven manipulation of bias induced via familiarity. In the first two Experiments, and in the low familiarity condition of Experiment 3, we found evidence of an early frontocentral ERP component at 320 ms poststimulus (the FN320 that was sensitive to the manipulation of bias via instruction, with more negative amplitudes indexing more liberal bias. By contrast, later during the trial (500-700 ms poststimulus, bias effects interacted with old/new effects across all three experiments. Results suggest that the decision criterion is typically activated early during recognition memory trials, and is integrated with retrieved memory signals and task-specific processing demands later during the trial. More generally, the findings demonstrate how ERPs can help to specify the dynamics of recognition memory processes under top-down and bottom-up controlled retrieval conditions.

  3. Research on the Reliability Testing of Electrical Automation Control Equipment

    OpenAIRE

    Yongjie Luo

    2014-01-01

    According to the author’s many years’ work experience, this paper first discusses the concepts of electrical automation control equipment reliability testing, and then analyzes the test method of electrical automation control equipment reliability testing, finally, on this basis, this article discusses how to determine the reliability test method of electrical automation control equipment. Results of this study will provide a useful reference for electrical automation control equipment reliab...

  4. Boise Hydrogeophysical Research Site: Control Volume/Test Cell and Community Research Asset

    Science.gov (United States)

    Barrash, W.; Bradford, J.; Malama, B.

    2008-12-01

    The Boise Hydrogeophysical Research Site (BHRS) is a research wellfield or field-scale test facility developed in a shallow, coarse, fluvial aquifer with the objectives of supporting: (a) development of cost- effective, non- or minimally-invasive quantitative characterization and imaging methods in heterogeneous aquifers using hydrologic and geophysical techniques; (b) examination of fundamental relationships and processes at multiple scales; (c) testing theories and models for groundwater flow and solute transport; and (d) educating and training of students in multidisciplinary subsurface science and engineering. The design of the wells and the wellfield support modular use and reoccupation of wells for a wide range of single-well, cross-hole, multiwell and multilevel hydrologic, geophysical, and combined hydrologic-geophysical experiments. Efforts to date by Boise State researchers and collaborators have been largely focused on: (a) establishing the 3D distributions of geologic, hydrologic, and geophysical parameters which can then be used as the basis for jointly inverting hard and soft data to return the 3D K distribution and (b) developing subsurface measurement and imaging methods including tomographic characterization and imaging methods. At this point the hydrostratigraphic framework of the BHRS is known to be a hierarchical multi-scale system which includes layers and lenses that are recognized with geologic, hydrologic, radar, seismic, and EM methods; details are now emerging which may allow 3D deterministic characterization of zones and/or material variations at the meter scale in the central wellfield. Also the site design and subsurface framework have supported a variety of testing configurations for joint hydrologic and geophysical experiments. Going forward we recognize the opportunity to increase the R&D returns from use of the BHRS with additional infrastructure (especially for monitoring the vadose zone and surface water-groundwater interactions

  5. Nondestructive testing and evaluation of wood : a worldwide research update

    Science.gov (United States)

    Brian K. Brashaw; Voichita Bucur; Ferenc Divos; Raquel Goncalves; Jianxiong Lu; Roger Meder; Roy F. Pellerin; Simon Potter; Robert J Ross; Xiping Wang; Yafang. Yin

    2009-01-01

    The international forest products research community is responding to these driving forces by conducting NDT/NDE research to provide the technologies needed to address these challenges. This article presents a sample of the on-going NDT/NDE research efforts being conducted in several areas of the world.

  6. Good practices for quantitative bias analysis.

    Science.gov (United States)

    Lash, Timothy L; Fox, Matthew P; MacLehose, Richard F; Maldonado, George; McCandless, Lawrence C; Greenland, Sander

    2014-12-01

    Quantitative bias analysis serves several objectives in epidemiological research. First, it provides a quantitative estimate of the direction, magnitude and uncertainty arising from systematic errors. Second, the acts of identifying sources of systematic error, writing down models to quantify them, assigning values to the bias parameters and interpreting the results combat the human tendency towards overconfidence in research results, syntheses and critiques and the inferences that rest upon them. Finally, by suggesting aspects that dominate uncertainty in a particular research result or topic area, bias analysis can guide efficient allocation of sparse research resources. The fundamental methods of bias analyses have been known for decades, and there have been calls for more widespread use for nearly as long. There was a time when some believed that bias analyses were rarely undertaken because the methods were not widely known and because automated computing tools were not readily available to implement the methods. These shortcomings have been largely resolved. We must, therefore, contemplate other barriers to implementation. One possibility is that practitioners avoid the analyses because they lack confidence in the practice of bias analysis. The purpose of this paper is therefore to describe what we view as good practices for applying quantitative bias analysis to epidemiological data, directed towards those familiar with the methods. We focus on answering questions often posed to those of us who advocate incorporation of bias analysis methods into teaching and research. These include the following. When is bias analysis practical and productive? How does one select the biases that ought to be addressed? How does one select a method to model biases? How does one assign values to the parameters of a bias model? How does one present and interpret a bias analysis?. We hope that our guide to good practices for conducting and presenting bias analyses will encourage

  7. Symmetry as Bias: Rediscovering Special Relativity

    Science.gov (United States)

    Lowry, Michael R.

    1992-01-01

    This paper describes a rational reconstruction of Einstein's discovery of special relativity, validated through an implementation: the Erlanger program. Einstein's discovery of special relativity revolutionized both the content of physics and the research strategy used by theoretical physicists. This research strategy entails a mutual bootstrapping process between a hypothesis space for biases, defined through different postulated symmetries of the universe, and a hypothesis space for physical theories. The invariance principle mutually constrains these two spaces. The invariance principle enables detecting when an evolving physical theory becomes inconsistent with its bias, and also when the biases for theories describing different phenomena are inconsistent. Structural properties of the invariance principle facilitate generating a new bias when an inconsistency is detected. After a new bias is generated. this principle facilitates reformulating the old, inconsistent theory by treating the latter as a limiting approximation. The structural properties of the invariance principle can be suitably generalized to other types of biases to enable primal-dual learning.

  8. Visual search attentional bias modification reduced social phobia in adolescents.

    Science.gov (United States)

    De Voogd, E L; Wiers, R W; Prins, P J M; Salemink, E

    2014-06-01

    An attentional bias for negative information plays an important role in the development and maintenance of (social) anxiety and depression, which are highly prevalent in adolescence. Attention Bias Modification (ABM) might be an interesting tool in the prevention of emotional disorders. The current study investigated whether visual search ABM might affect attentional bias and emotional functioning in adolescents. A visual search task was used as a training paradigm; participants (n = 16 adolescents, aged 13-16) had to repeatedly identify the only smiling face in a 4 × 4 matrix of negative emotional faces, while participants in the control condition (n = 16) were randomly allocated to one of three placebo training versions. An assessment version of the task was developed to directly test whether attentional bias changed due to the training. Self-reported anxiety and depressive symptoms and self-esteem were measured pre- and post-training. After two sessions of training, the ABM group showed a significant decrease in attentional bias for negative information and self-reported social phobia, while the control group did not. There were no effects of training on depressive mood or self-esteem. No correlation between attentional bias and social phobia was found, which raises questions about the validity of the attentional bias assessment task. Also, the small sample size precludes strong conclusions. Visual search ABM might be beneficial in changing attentional bias and social phobia in adolescents, but further research with larger sample sizes and longer follow-up is needed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. An inclusive taxonomy of behavioral biases

    OpenAIRE

    David Peón; Manel Antelo; Anxo Calvo-Silvosa

    2017-01-01

    This paper overviews the theoretical and empirical research on behavioral biases and their influence in the literature. To provide a systematic exposition, we present a unified framework that takes the reader through an original taxonomy, based on the reviews of relevant authors in the field. In particular, we establish three broad categories that may be distinguished: heuristics and biases; choices, values and frames; and social factors. We then describe the main biases within each category,...

  10. Testing day: The effects of processing bias induced by Navon stimuli on the strength of the Müller-Lyer illusion.

    Science.gov (United States)

    Mundy, Matthew E

    2014-01-01

    Explanations for the cognitive basis of the Müller-Lyer illusion are still frustratingly mixed. To date, Day's (1989) theory of perceptual compromise has received little empirical attention. In this study, we examine the merit of Day's hypothesis for the Müller-Lyer illusion by biasing participants toward global or local visual processing through exposure to Navon (1977) stimuli, which are known to alter processing level preference for a short time. Participants (N = 306) were randomly allocated to global, local, or control conditions. Those in global or local conditions were exposed to Navon stimuli for 5 min and participants were required to report on the global or local stimulus features, respectively. Subsequently, participants completed a computerized Müller-Lyer experiment where they adjusted the length of a line to match an illusory-figure. The illusion was significantly stronger for participants with a global bias, and significantly weaker for those with a local bias, compared with the control condition. These findings provide empirical support for Day's "conflicting cues" theory of perceptual compromise in the Müller-Lyer illusion.

  11. Borehole heater test at KAERI Underground Research Tunnel

    International Nuclear Information System (INIS)

    Kwon, S. K.; Cho, W. J.; Jeon, S. W.

    2009-09-01

    At HLW repository, the temperature change due to the decay heat in near field can affect the hydraulic, mechanical, and chemical behaviors and influence on the repository safety. Therefore, the understanding of the thermal behavior in near field is essential for the site selection, design, as well as operation of the repository. In this study, various studies for the in situ heater test, which is for the investigation of the thermo-mechanical behavior in rock mass, were carried out. At first, similar in situ tests at foreign URLs were reviewed and summarized the major conclusions from the tests. After then an adequate design of heater, observation sensors, and data logging system were developed and installed with a consideration of the site condition and test purposes. In order to minimize the effect of hydraulic phenomenon, a relatively day zone was chosen for the in situ test. Joint distribution and characteristics in the zone were surveyed and the rock mass properties were determined with various laboratory tests. In this study, an adequate location for an in situ borehole heater test was chosen. Also a heater for the test was designed and manufactured and the sensors for measuring the rock behavior were installed. It was possible to observe that stiff joints are developed overwhelmingly in the test area from the joint survey at the tunnel wall. The major rock and rock mass properties at the test site could be determined from the thermo-mechanical laboratory tests using the rock cores retrieved from the site. The measured data were implemented in the three-dimensional computer simulation. From the modeling using FLAC3D code, it was possible to find that the heat convection through the tunnel wall can influence on temperature distribution in rock. Because of that it was necessary to installed a blocking wall to minimize the effect of ventilation system on the heater test, which is carrying out nearby the tunnel wall. The in situ borehole heater test is the first

  12. Feasibility of using Ohmsett for dispersant testing and research

    International Nuclear Information System (INIS)

    Ross, S.L.; Buist, I.A.; Potter, S.G.; Belore, R.C.

    2000-01-01

    Laboratory dispersant testing proved to be of limited value for the prediction of actual dispersant effectiveness in spill situations. Variables such as oil type, weathered state, dispersant type, dispersant-to-oil ratio application method etc. were difficult to reproduce. A feasibility study was conducted at the Ohmsett facility in Leonardo, New Jersey to determine if the site was suitable for dispersant effectiveness testing. The study consisted of four phases: (1) interfacial tension laboratory tests, (2) turbidity tests, (3) the determination of the efficiency of filtering materials at the facility and alternative filtering materials, and (3) full-scale testing. Results indicated that dispersant in the water after the tests affected the interfacial tension of oils used in other tests following this one. Noticeable dispersion of floating oil occurred only after the concentration of dispersant in the water reached 400 ppm, making it possible to conduct consecutive experiments without having to worry about residual dispersant in the tank. The filtering of water to remove the dispersed oil was only required after several experiments had taken place on a given day. Evidently, it was only possible to have an underwater view of the dispersant testing during the first test of a series. The use of cellulose to aid the filtering at the facility removed most of the dispersed oil. The use of activated carbon resulted in a high degree of efficiency for the removal of dissolved dispersant. The testing of dispersant at Ohmsett proved possible as long as the design and implementation phases of the testing program respected the limitations stipulated above. 3 refs., 3 tabs., 3 figs

  13. CERDA: testing and research center of Delle-Alsthom

    Energy Technology Data Exchange (ETDEWEB)

    Maury, E; Lavaut, M; Vigreux, J

    1960-03-01

    Features of a new testing plant and detailed descriptions of machinery used, including two 12-kV 2500 Mva alternators, transformers to step up voltage to 496 kV, h-v apparatus to produce voltages up to 750 kV and impulse voltages up to 4 x 10/sup 6/ v, and methods of testing and measurement are discussed.

  14. Rotor blade full-scale fatigue testing technology and research

    DEFF Research Database (Denmark)

    Nielsen, Per Hørlyk; Berring, Peter; Pavese, Christian

    was started in the beginning of the 1980´s and has been further developed since then. Structures in composite materials are generally difficult and time consuming to test for fatigue resistance. Therefore, several methods for testing of blades have been developed and exist today. These methods...

  15. Negativity Bias in Dangerous Drivers.

    Directory of Open Access Journals (Sweden)

    Jing Chai

    Full Text Available The behavioral and cognitive characteristics of dangerous drivers differ significantly from those of safe drivers. However, differences in emotional information processing have seldom been investigated. Previous studies have revealed that drivers with higher anger/anxiety trait scores are more likely to be involved in crashes and that individuals with higher anger traits exhibit stronger negativity biases when processing emotions compared with control groups. However, researchers have not explored the relationship between emotional information processing and driving behavior. In this study, we examined the emotional information processing differences between dangerous drivers and safe drivers. Thirty-eight non-professional drivers were divided into two groups according to the penalty points that they had accrued for traffic violations: 15 drivers with 6 or more points were included in the dangerous driver group, and 23 drivers with 3 or fewer points were included in the safe driver group. The emotional Stroop task was used to measure negativity biases, and both behavioral and electroencephalograph data were recorded. The behavioral results revealed stronger negativity biases in the dangerous drivers than in the safe drivers. The bias score was correlated with self-reported dangerous driving behavior. Drivers with strong negativity biases reported having been involved in mores crashes compared with the less-biased drivers. The event-related potentials (ERPs revealed that the dangerous drivers exhibited reduced P3 components when responding to negative stimuli, suggesting decreased inhibitory control of information that is task-irrelevant but emotionally salient. The influence of negativity bias provides one possible explanation of the effects of individual differences on dangerous driving behavior and traffic crashes.

  16. News Consumption and Media Bias

    OpenAIRE

    Yi Xiang; Miklos Sarvary

    2007-01-01

    Bias in the market for news is well-documented. Recent research in economics explains the phenomenon by assuming that consumers want to read (watch) news that is consistent with their tastes or prior beliefs rather than the truth. The present paper builds on this idea but recognizes that (i) besides “biased” consumers, there are also “conscientious” consumers whose sole interest is in discovering the truth, and (ii) consistent with reality, media bias is constrained by the truth. These two fa...

  17. Exchange bias theory

    International Nuclear Information System (INIS)

    Kiwi, Miguel

    2001-01-01

    Research on the exchange bias (EB) phenomenon has witnessed a flurry of activity during recent years, which stems from its use in magnetic sensors and as stabilizers in magnetic reading heads. EB was discovered in 1956 but it attracted only limited attention until these applications, closely related to giant magnetoresistance, were developed during the last decade. In this review, I initially give a short introduction, listing the most salient experimental results and what is required from an EB theory. Next, I indicate some of the obstacles in the road towards a satisfactory understanding of the phenomenon. The main body of the text reviews and critically discusses the activity that has flourished, mainly during the last 5 years, in the theoretical front. Finally, an evaluation of the progress made, and a critical assessment as to where we stand nowadays along the road to a satisfactory theory, is presented

  18. Nuclear fuels technologies fiscal year 1996 research and research development test results

    International Nuclear Information System (INIS)

    Beard, C.A.; Blair, H.T.; Buksa, J.J.; Butt, D.P.

    1996-01-01

    During fiscal year 1996, the Department of Energy's Office of Fissile Materials Disposition (OFMD) funded Los Alamos National Laboratory (LANL) to investigate issues associated with the fabrication of plutonium from dismantled weapons into mixed-oxide (MOX) nuclear fuel for disposition in nuclear power reactors. These issues can be divided into two main categories: issues associated with the fact that the plutonium from dismantled weapons contains gallium, and issues associated with the unique characteristics of the PuO 2 produced by the dry conversion process that OFMD is proposing to convert the weapons material. Initial descriptions of the experimental work performed in fiscal year 1996 to address these issues can be found in Nuclear Fuels Technologies Fiscal Year 1996 Research and Development Test Matrices'. However, in some instances the change in programmatic emphasis towards the Parallex program either altered the manner in which some of these experiments were performed (i.e., the work was done as part of the Parallex fabrication development and not as individual separate-effects tests as originally envisioned) or delayed the experiments into Fiscal Year 1997. This report reviews the experiments that were conducted and presents the results. 7 figs., 14 tabs

  19. Impact of Participatory Health Research: A Test of the Community-Based Participatory Research Conceptual Model

    Directory of Open Access Journals (Sweden)

    John G. Oetzel

    2018-01-01

    Full Text Available Objectives. A key challenge in evaluating the impact of community-based participatory research (CBPR is identifying what mechanisms and pathways are critical for health equity outcomes. Our purpose is to provide an empirical test of the CBPR conceptual model to address this challenge. Methods. A three-stage quantitative survey was completed: (1 294 US CBPR projects with US federal funding were identified; (2 200 principal investigators completed a questionnaire about project-level details; and (3 450 community or academic partners and principal investigators completed a questionnaire about perceived contextual, process, and outcome variables. Seven in-depth qualitative case studies were conducted to explore elements of the model not captured in the survey; one is presented due to space limitations. Results. We demonstrated support for multiple mechanisms illustrated by the conceptual model using a latent structural equation model. Significant pathways were identified, showing the positive association of context with partnership structures and dynamics. Partnership structures and dynamics showed similar associations with partnership synergy and community involvement in research; both of these had positive associations with intermediate community changes and distal health outcomes. The case study complemented and extended understandings of the mechanisms of how partnerships can improve community conditions. Conclusions. The CBPR conceptual model is well suited to explain key relational and structural pathways for impact on health equity outcomes.

  20. 15N-ammonium test in clinical research

    International Nuclear Information System (INIS)

    Jung, K.; Metzner, C.; Teichmann, B.; Leipzig Univ.

    1989-01-01

    By use of the 15 N-ammonium test the liver function is investigated under influence of hormonal contraceptives in women and in liver diseases in children. With the described noninvasive nonradioactive isotope test the ammonia detoxification capability and the urea synthesis capacity of the liver is determined by measuring of the 15 N excretion in ammonia and urea in urine after oral administering of 15 N-ammonium chloride. The 15 N-ammonium test shows a significant influence of the hormonal contraceptives on the liver function and gives diagnostic evidence for liver diseases in children. (author)

  1. Numerical value biases sound localization.

    Science.gov (United States)

    Golob, Edward J; Lewald, Jörg; Getzmann, Stephan; Mock, Jeffrey R

    2017-12-08

    Speech recognition starts with representations of basic acoustic perceptual features and ends by categorizing the sound based on long-term memory for word meaning. However, little is known about whether the reverse pattern of lexical influences on basic perception can occur. We tested for a lexical influence on auditory spatial perception by having subjects make spatial judgments of number stimuli. Four experiments used pointing or left/right 2-alternative forced choice tasks to examine perceptual judgments of sound location as a function of digit magnitude (1-9). The main finding was that for stimuli presented near the median plane there was a linear left-to-right bias for localizing smaller-to-larger numbers. At lateral locations there was a central-eccentric location bias in the pointing task, and either a bias restricted to the smaller numbers (left side) or no significant number bias (right side). Prior number location also biased subsequent number judgments towards the opposite side. Findings support a lexical influence on auditory spatial perception, with a linear mapping near midline and more complex relations at lateral locations. Results may reflect coding of dedicated spatial channels, with two representing lateral positions in each hemispace, and the midline area represented by either their overlap or a separate third channel.

  2. Cognitive testing of pigs (Sus scrofa) in translational biobehavioral research

    DEFF Research Database (Denmark)

    Kornum, Birgitte R; Knudsen, Gitte M

    2011-01-01

    Within neuroscience and biobehavioral research, the pig (Sus scrofus) is increasingly being acknowledged as a valuable large animal species. Compared to the rodent brain, the pig brain more closely resembles the human brain in terms of both anatomy and biochemistry, which associates the pig...... of farm animal welfare researchers, but it has only recently received interest in the wider neuroscience community. Several behavioral tasks have successfully been adapted to the pig, and valuable results have been produced. However, most tasks have only been established at a single research facility...

  3. Space shuttle pilot-induced-oscillation research testing

    Science.gov (United States)

    Powers, B. G.

    1984-01-01

    The simulation requirements for investigation of pilot-induced-oscillation (PIO) characteristics during the landing phase are discussed. Orbiters simulations and F-8 digital fly-by-wire aircraft tests are addressed.

  4. Field Testing Research at the NWTC (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2015-02-01

    The National Wind Technology Center (NWTC) at the National Renewable Laboratory (NREL) has extensive field testing capabilities that have been used in collaboration with the wind industry to accelerate wind technology development and deployment for more than 30 years.

  5. Direct sunlight facility for testing and research in HCPV

    International Nuclear Information System (INIS)

    Sciortino, Luisa; Agnello, Simonpietro; Bonsignore, Gaetano; Cannas, Marco; Gelardi, Franco Mario; Napoli, Gianluca; Spallino, Luisa; Barbera, Marco; Buscemi, Alessandro; Montagnino, Fabio Maria; Paredes, Filippo; Candia, Roberto; Collura, Alfonso; Di Cicca, Gaspare; Cicero, Ugo Lo; Varisco, Salvo

    2014-01-01

    A facility for testing different components for HCPV application has been developed in the framework of 'Fotovoltaico ad Alta Efficienza' (FAE) project funded by the Sicilian Regional Authority (PO FESR Sicilia 2007/2013 4.1.1.1). The testing facility is equipped with an heliostat providing a wide solar beam inside the lab, an optical bench for mounting and aligning the HCPV components, electronic equipments to characterize the I-V curves of multijunction cells operated up to 2000 suns, a system to circulate a fluid in the heat sink at controlled temperature and flow-rate, a data logging system with sensors to measure temperatures in several locations and fluid pressures at the inlet and outlet of the heat sink, and a climatic chamber with large test volume to test assembled HCPV modules

  6. Correlation of geotextile puncture test methods : research brief.

    Science.gov (United States)

    2017-05-01

    Geotextiles are commonly used in pavements, earth retaining structures, landfills and other geotechnical contexts. Various tests are conducted to evaluate and classify geotextiles to determine their suitability for each of these applications. The AST...

  7. Effects of interpretation training on hostile attribution bias and reactivity to interpersonal insult.

    Science.gov (United States)

    Hawkins, Kirsten A; Cougle, Jesse R

    2013-09-01

    Research suggests that individuals high in anger have a bias for attributing hostile intentions to ambiguous situations. The current study tested whether this interpretation bias can be altered to influence anger reactivity to an interpersonal insult using a single-session cognitive bias modification program. One hundred thirty-five undergraduate students were randomized to receive positive training, negative training, or a control condition. Anger reactivity to insult was then assessed. Positive training led to significantly greater increases in positive interpretation bias relative to the negative group, though these increases were only marginally greater than the control group. Negative training led to increased negative interpretation bias relative to other groups. During the insult, participants in the positive condition reported less anger than those in the control condition. Observers rated participants in the positive condition as less irritated than those in the negative condition and more amused than the other two conditions. Though mediation of effects via bias modification was not demonstrated, among the positive condition posttraining interpretation bias was correlated with self-reported anger, suggesting that positive training reduced anger reactivity by influencing interpretation biases. Findings suggest that positive interpretation training may be a promising treatment for reducing anger. However, the current study was conducted with a non-treatment-seeking student sample; further research with a treatment-seeking sample with problematic anger is necessary. Copyright © 2013. Published by Elsevier Ltd.

  8. [Clinical research IV. Relevancy of the statistical test chosen].

    Science.gov (United States)

    Talavera, Juan O; Rivas-Ruiz, Rodolfo

    2011-01-01

    When we look at the difference between two therapies or the association of a risk factor or prognostic indicator with its outcome, we need to evaluate the accuracy of the result. This assessment is based on a judgment that uses information about the study design and statistical management of the information. This paper specifically mentions the relevance of the statistical test selected. Statistical tests are chosen mainly from two characteristics: the objective of the study and type of variables. The objective can be divided into three test groups: a) those in which you want to show differences between groups or inside a group before and after a maneuver, b) those that seek to show the relationship (correlation) between variables, and c) those that aim to predict an outcome. The types of variables are divided in two: quantitative (continuous and discontinuous) and qualitative (ordinal and dichotomous). For example, if we seek to demonstrate differences in age (quantitative variable) among patients with systemic lupus erythematosus (SLE) with and without neurological disease (two groups), the appropriate test is the "Student t test for independent samples." But if the comparison is about the frequency of females (binomial variable), then the appropriate statistical test is the χ(2).

  9. A comparator-hypothesis account of biased contingency detection.

    Science.gov (United States)

    Vadillo, Miguel A; Barberia, Itxaso

    2018-02-12

    Our ability to detect statistical dependencies between different events in the environment is strongly biased by the number of coincidences between them. Even when there is no true covariation between a cue and an outcome, if the marginal probability of either of them is high, people tend to perceive some degree of statistical contingency between both events. The present paper explores the ability of the Comparator Hypothesis to explain the general pattern of results observed in this literature. Our simulations show that this model can account for the biasing effects of the marginal probabilities of cues and outcomes. Furthermore, the overall fit of the Comparator Hypothesis to a sample of experimental conditions from previous studies is comparable to that of the popular Rescorla-Wagner model. These results should encourage researchers to further explore and put to the test the predictions of the Comparator Hypothesis in the domain of biased contingency detection. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Global-local visual biases correspond with visual-spatial orientation.

    Science.gov (United States)

    Basso, Michael R; Lowery, Natasha

    2004-02-01

    Within the past decade, numerous investigations have demonstrated reliable associations of global-local visual processing biases with right and left hemisphere function, respectively (cf. Van Kleeck, 1989). Yet the relevance of these biases to other cognitive functions is not well understood. Towards this end, the present research examined the relationship between global-local visual biases and perception of visual-spatial orientation. Twenty-six women and 23 men completed a global-local judgment task (Kimchi and Palmer, 1982) and the Judgment of Line Orientation Test (JLO; Benton, Sivan, Hamsher, Varney, and Spreen, 1994), a measure of visual-spatial orientation. As expected, men had better performance on JLO. Extending previous findings, global biases were related to better visual-spatial acuity on JLO. The findings suggest that global-local biases and visual-spatial orientation may share underlying cerebral mechanisms. Implications of these findings for other visually mediated cognitive outcomes are discussed.

  11. Gender bias in leader evaluations: merging implicit theories and role congruity perspectives.

    Science.gov (United States)

    Hoyt, Crystal L; Burnette, Jeni L

    2013-10-01

    This research extends our understanding of gender bias in leader evaluations by merging role congruity and implicit theory perspectives. We tested and found support for the prediction that the link between people's attitudes regarding women in authority and their subsequent gender-biased leader evaluations is significantly stronger for entity theorists (those who believe attributes are fixed) relative to incremental theorists (those who believe attributes are malleable). In Study 1, 147 participants evaluated male and female gubernatorial candidates. Results supported predictions, demonstrating that traditional attitudes toward women in authority significantly predicted a pro-male gender bias in leader evaluations (and progressive attitudes predicted a pro-female gender bias) with an especially strong effect for those with more entity-oriented, relative to incrementally oriented person theories. Study 2 (119 participants) replicated these findings and demonstrated the mediating role of these attitudes in linking gender stereotypes and leader role expectations to biased evaluations.

  12. Measuring Values in Environmental Research: A Test of an Environmental Portrait Value Questionnaire

    Science.gov (United States)

    Bouman, Thijs; Steg, Linda; Kiers, Henk A. L.

    2018-01-01

    Four human values are considered to underlie individuals’ environmental beliefs and behaviors: biospheric (i.e., concern for environment), altruistic (i.e., concern for others), egoistic (i.e., concern for personal resources) and hedonic values (i.e., concern for pleasure and comfort). These values are typically measured with an adapted and shortened version of the Schwartz Value Survey (SVS), to which we refer as the Environmental-SVS (E-SVS). Despite being well-validated, recent research has indicated some concerns about the SVS methodology (e.g., comprehensibility, self-presentation biases) and suggested an alternative method of measuring human values: The Portrait Value Questionnaire (PVQ). However, the PVQ has not yet been adapted and applied to measure values most relevant to understand environmental beliefs and behaviors. Therefore, we tested the Environmental-PVQ (E-PVQ) – a PVQ variant of E-SVS –and compared it with the E-SVS in two studies. Our findings provide strong support for the validity and reliability of both the E-SVS and E-PVQ. In addition, we find that respondents slightly preferred the E-PVQ over the E-SVS (Study 1). In general, both scales correlate similarly to environmental self-identity (Study 1), energy behaviors (Studies 1 and 2), pro-environmental personal norms, climate change beliefs and policy support (Study 2). Accordingly, both methodologies show highly similar results and seem well-suited for measuring human values underlying environmental behaviors and beliefs. PMID:29743874

  13. The Audiovisual Vocational Preferences Test: A Research Note on Test Development.

    Science.gov (United States)

    Wilgosh, Lorraine

    1992-01-01

    This paper reports on the development of the Audiovisual Vocational Preferences Test to facilitate career planning for adolescents and young adults with mild to moderate intellectual impairments. The strategies involved in test construction, data on initial use of the test, and improvements in format and content after pilot testing are discussed.…

  14. Distinctive Characteristics of Sexual Orientation Bias Crimes

    Science.gov (United States)

    Stacey, Michele

    2011-01-01

    Despite increased attention in the area of hate crime research in the past 20 years, sexual orientation bias crimes have rarely been singled out for study. When these types of crimes are looked at, the studies are typically descriptive in nature. This article seeks to increase our knowledge of sexual orientation bias by answering the question:…

  15. The Battle over Studies of Faculty Bias

    Science.gov (United States)

    Gravois, John

    2007-01-01

    The American Federation of Teachers (AFT) recently commissioned a study to review the research that finds liberal bias run amok in academe. Believing that the AFT is not a dispassionate observer of this debate, this article provides "The Chronicle of Higher Education's" survey of the genre. The studies reviewed include: (1) "Political Bias in the…

  16. Research on Test-bench for Sonic Logging Tool

    Directory of Open Access Journals (Sweden)

    Xianping Liu

    2016-01-01

    Full Text Available In this paper, the test-bench for sonic logging tool is proposed and designed to realize automatic calibration and testing of the sonic logging tool. The test-bench System consists of Host Computer, Embedded Controlling Board, and functional boards. The Host Computer serves as the Human Machine Interface (HMI and processes uploaded data. The software running on Host Computer is designed on VC++, which is developed based on multithreading, Dynamic Linkable Library (DLL and Multiple Document Interface (MDI techniques. The Embedded Controlling Board uses ARM7 as the microcontroller and communicates with Host Computer via Ethernet. The Embedded Controlling Board software is realized based on embedded uclinux operating system with a layered architecture. The functional boards are designed based on Field Programmable Gate Array (FPGA and provide test interfaces for the logging tool. The functional board software is divided into independent sub-modules that can repeatedly be used by various functional boards and then integrated those sub-modules in the top layer. With the layered architecture and modularized design, the software system is highly reliable and extensible. With the help of designed system, a test has been conducted quickly and successfully on the electronic receiving cabin of the sonic logging tool. It demonstrated that the system could greatly improve the production efficiency of the sonic logging tool.

  17. Research on the Testing Methods for IBIS-S System

    International Nuclear Information System (INIS)

    Xing, C; Zhou, X; Wang, P; Yu, Z Q

    2014-01-01

    The basic theoretical principles and key techniques of the IBIS-S system, which is a micro-deformation monitoring system based on the techniques of GB-InSAR, are introduced. The accuracy of IBIS-S is much higher than that of traditional deformation monitoring devices, so it is necessary to test the accuracy and reliability of the system. Some comparison experiments are designed for testing the parameters provided by the manufacturer, and these tests verify the accuracy and resolution of IBIS-S. A Leica TCRP 1201 total station (with an accuracy of 1mm + 1ppm) and a stepping motor (with an accuracy of 0.001mm) are used for testing the monitoring accuracy of IBIS-S. The results from different tests show that the monitoring data of IBIS-S is very accurate and higher than the traditional total station. The results also indicate that IBIS-S can be applied in the micro-deformation projects of high-rise buildings, bridges and some other objects with a high accuracy

  18. Research on the design of fixture for motor vibration test

    Science.gov (United States)

    Shen, W. X.; Ma, W. S.; Zhang, L. W.

    2018-03-01

    The vibration reliability of the new energy automobile motor plays a very important role in driving safety, so it is very important to test the vibration durability of the motor. In the vibration test process, the fixture is very important, simulated road spectrum signal vibration can be transmitted without distortion to the motor through the fixture, fixture design directly affect the result of vibration endurance test. On the basis of new energy electric vehicle motor concrete structure, Two fixture design and fixture installation schemes for lateral cantilever type and base bearing type are put forward in this article, the selection of material, weighting process, middle alignment process and manufacturing process are summarized.The modal analysis and frequency response calculation of the fixture are carried out in this design, combine with influence caused by fixture height and structure profile on response frequency, the response frequency of each order of the fixture is calculated, then ultimately achieve the purpose of guiding the design.

  19. Lightning Tests on the WC-130 Research Aircraft.

    Science.gov (United States)

    1982-12-01

    in the WC-136 tests at various times.) E- Feild Fiber Optic Test Article Sensor Transmitter (Typ)WiePr Indtuced Voltag Sensor"" *Fiber I"=Current optic...well-characterized. 5.1 Skin Current Measurements Skin current vectors were measured at five fuselage locations on the left side of the WC-130 at a...MGL-S7) which were mounted so that they sampled two orthogonal components of the skin current vector . The measured responses were then inte- grated

  20. 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.

  1. Product Aggregation Bias as a Specification Error in Demand Systems

    OpenAIRE

    George C. Davis

    1997-01-01

    Inherent in all demand studies is some form of product aggregation which can lead to product aggregation bias. This article develops a simple procedure for incorporating product aggregation bias in demand systems that permits testing of product aggregation bias with a standard likelihood ratio test. An empirical illustration of the procedure demonstrates the importance of proper product aggregation. Copyright 1997, Oxford University Press.

  2. Supervisory Presentation for Research, Information, Integration and Testing (SPRINT)

    Science.gov (United States)

    2015-03-29

    in Microsoft Visual Studio and several third party developer libraries (See Figure 4). All distributed laboratory sites have similar hardware...Testing (SPRINT). 15. SUBJECT TERMS Supervisory Control, Multi-Modal Interfaces, Scalable Interfaces, Advanced Visualization , Augmented Symbology 16...23 Figure 9. Fusion Visual Framework Components

  3. Profiles of facilities used for HTR research and testing

    International Nuclear Information System (INIS)

    1980-05-01

    This report contains a current description of facilities supporting HTR research and development submitted by countries participating in the IWGFR. It has the purpose of providing an overview of the facilities available for use and of the types of experiments that can be conducted therein

  4. Accelerated ultrasonic fatigue testing applications and research trends

    Energy Technology Data Exchange (ETDEWEB)

    Cho, In Sik; Shin, Choongshig; Kim, Jong Yup; Jeon, Yongho [Ajou Univ., Gyeonggi (Somalia)

    2012-06-15

    Very high cycle fatigue (VHCF) behavior of aerospace components has emerged much attention due to their long service life. In this study, a piezoelectric ultrasonic fatigue testing (UFT) system has been developed by Mbrosiatec Co., Ltd. to study the high cycle fatigue (HCF) strength of Ti 6Al 4V alloy. Hourglass shaped specimens have been investigated in the range from 10'6' to 10'9' cycles at room temperature under completely reversed R=-1 loading conditions, Scanning electron microscopy (SEM) analysis revealed that failures occurred in the entire range up to the gigacycle regime, and the fractures have been found to be initiated from the surface, unlike in steels. However, it was found from the SEM microgprahs that microcracks transformed into intergranular fractures. Thus, it can be concluded from according to the results that this test method can be applicable to commercialized automotive and railroad parts that require high cycle fatigue strength.

  5. Accelerated ultrasonic fatigue testing applications and research trends

    International Nuclear Information System (INIS)

    Cho, In Sik; Shin, Choongshig; Kim, Jong Yup; Jeon, Yongho

    2012-01-01

    Very high cycle fatigue (VHCF) behavior of aerospace components has emerged much attention due to their long service life. In this study, a piezoelectric ultrasonic fatigue testing (UFT) system has been developed by Mbrosiatec Co., Ltd. to study the high cycle fatigue (HCF) strength of Ti 6Al 4V alloy. Hourglass shaped specimens have been investigated in the range from 10'6' to 10'9' cycles at room temperature under completely reversed R=-1 loading conditions, Scanning electron microscopy (SEM) analysis revealed that failures occurred in the entire range up to the gigacycle regime, and the fractures have been found to be initiated from the surface, unlike in steels. However, it was found from the SEM microgprahs that microcracks transformed into intergranular fractures. Thus, it can be concluded from according to the results that this test method can be applicable to commercialized automotive and railroad parts that require high cycle fatigue strength

  6. Research on Multichannel Test Device of Missile Fuze

    Directory of Open Access Journals (Sweden)

    Guoyong Zhen

    2014-05-01

    Full Text Available This paper introduces the design of multichannel acquisition circuit based on FPGA which samples and records the Doppler signals, ignition signal and the working condition of fuze security enforcement agencies of missile fuze in real-time in the test of high speed dynamic intersection. Furthermore, for the problem of increasing number of sample channel which causes the complexity of the multiplexer control, a general programmable channel switching method is proposed based on FPGA. In the method, FPGA is the control core, and using the internal ROM resource effectively simplifies the complexity of channel switch in the multichannel acquisition system. This paper analyzes the acquisition system design, and describes the design of hardware circuit and analog switch address coding in detail. The test result shows that the acquisition circuit meets the design requirements with high sampling precision and application value.

  7. Women and Educational Testing: A Selective Review of the Research Literature and Testing Practices.

    Science.gov (United States)

    Tittle, Carol Kehr; And Others

    This report provides an exploratory survey of several aspects of educational testing, with a view toward identifying discrimination against women. Two major ways in which discrimination can occur are examined in educational testing: reinforcement of sex-role stereotypes and restriction of individual choice. Major educational achievement tests are…

  8. Cognitive testing of pigs (Sus scrofa) in translational biobehavioral research

    DEFF Research Database (Denmark)

    Kornum, Birgitte R; Knudsen, Gitte M

    2011-01-01

    with a higher translational value. Several brain disorders have been fully or partially modeled in the pig and this has further spurred an interest in having access to behavioral tasks for pigs, and in particular to cognitive tasks. Cognitive testing of pigs has been conducted for several years by a small group......, and would benefit from further validation. This review presents the cognitive tasks that have been developed for pigs, their validation, and their current use....

  9. Research and developments on nondestructive testing in fabrications of fast breeder reactor structural components in Japan

    International Nuclear Information System (INIS)

    Ebata, M.; Ooka, K.; Miyoshi, S.; Senda, T.

    1985-01-01

    Research and developments (R and D) have been conducted on the nondestructive testing techniques necessary for the construction of fast breeder reactor (FBR). Radiographic tests have been made on tube-tube plate welds and small-diameter tube welds, etc. Ultrasonic tests have been conducted on austenitic stainless steel welds. In the penetrant tests and magnetic particle tests, the investigations have been performed on the effects of various test factors on the test results

  10. Report of test and research results on atomic energy obtained in national institutes in fiscal 1982

    International Nuclear Information System (INIS)

    1983-01-01

    As for the test and research on the utilization of atomic energy by national organizations, the budget was appropriated for the first time in fiscal year 1956. Since then, many valuable results of research have been produced in the diverse fields of nuclear fusion, safety research, food irradiation, medicine and others, in this way, the test and research have played large roles in the promotion of the utilization of atomic energy in Japan. This is the 23rd report, in which the results of the test and research on the utilization of atomic energy carried out in fiscal year 1982 by national organizations are summarized. 5 researches on nuclear fusion, 12 researches on engineering safety, 5 researches on environmental radioactivity safety, 3 researches on food irradiation, 5 researches on the countermeasures to cancer, 8 researches on soil fertilization, 4 researches on quality improvement, 7 researches on crop protection, 5 researches on the improvement of breeding, 8 researches on diagnosis and treatment, 8 researches on pharmaceuticals, 10 researches on the application to pathology, 6 researches on mining and industry, 6 researches on power reactors and nuclear ships, 1 research on underground water, 6 researches on activation analysis and 3 researches on injury prevention are reported. (Kako, I.)

  11. Present status and future perspective of research and test reactors in JAERI

    International Nuclear Information System (INIS)

    Baba, Osamu; Kaieda, Keisuke

    1999-01-01

    Since 1957, Japan Atomic Energy Research Institute (JAERI) has constructed several research and test reactors to fulfil a major role in the study of nuclear energy and fundamental research. At present, four reactors, the Japan Research Reactor No. 3 and No. 4 (JRR-3M and JRR-4 respectively), the Japan Materials Testing Reactor (JMTR) and the Nuclear Safety Research Reactor (NSRR), are in operation, and a new High Temperature Engineering Test Reactor (HTTR) has reached first criticality and is waiting for the power-up test. This paper introduce these reactors and describe their present operational status. The recent tendency of utilization and future perspectives are also reported. (author)

  12. Present status and future perspective of research and test reactors in JAERI

    Energy Technology Data Exchange (ETDEWEB)

    Baba, Osamu [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment; Kaieda, Keisuke

    1999-08-01

    Since 1957, Japan Atomic Energy Research Institute (JAERI) has constructed several research and test reactors to fulfil a major role in the study of nuclear energy and fundamental research. At present, four reactors, the Japan Research Reactor No. 3 and No. 4 (JRR-3M and JRR-4 respectively), the Japan Materials Testing Reactor (JMTR) and the Nuclear Safety Research Reactor (NSRR), are in operation, and a new High Temperature Engineering Test Reactor (HTTR) has reached first criticality and is waiting for the power-up test. This paper introduce these reactors and describe their present operational status. The recent tendency of utilization and future perspectives are also reported. (author)

  13. Photovoltaic Bias Generator

    Science.gov (United States)

    2018-02-01

    Department of the Army position unless so designated by other authorized documents. Citation of manufacturer’s or trade names does not constitute an... Interior view of the photovoltaic bias generator showing wrapped-wire side of circuit board...3 Fig. 4 Interior view of the photovoltaic bias generator showing component side of circuit board

  14. 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

  15. Attentional bias for positive emotional stimuli: A meta-analytic investigation.

    Science.gov (United States)

    Pool, Eva; Brosch, Tobias; Delplanque, Sylvain; Sander, David

    2016-01-01

    Despite an initial focus on negative threatening stimuli, researchers have more recently expanded the investigation of attentional biases toward positive rewarding stimuli. The present meta-analysis systematically compared attentional bias for positive compared with neutral visual stimuli across 243 studies (N = 9,120 healthy participants) that used different types of attentional paradigms and positive stimuli. Factors were tested that, as postulated by several attentional models derived from theories of emotion, might modulate this bias. Overall, results showed a significant, albeit modest (Hedges' g = .258), attentional bias for positive as compared with neutral stimuli. Moderator analyses revealed that the magnitude of this attentional bias varied as a function of arousal and that this bias was significantly larger when the emotional stimulus was relevant to specific concerns (e.g., hunger) of the participants compared with other positive stimuli that were less relevant to the participants' concerns. Moreover, the moderator analyses showed that attentional bias for positive stimuli was larger in paradigms that measure early, rather than late, attentional processing, suggesting that attentional bias for positive stimuli occurs rapidly and involuntarily. Implications for theories of emotion and attention are discussed. (c) 2015 APA, all rights reserved).

  16. Approximate Bias Correction in Econometrics

    OpenAIRE

    James G. MacKinnon; Anthony A. Smith Jr.

    1995-01-01

    This paper discusses ways to reduce the bias of consistent estimators that are biased in finite samples. It is necessary that the bias function, which relates parameter values to bias, should be estimable by computer simulation or by some other method. If so, bias can be reduced or, in some cases that may not be unrealistic, even eliminated. In general, several evaluations of the bias function will be required to do this. Unfortunately, reducing bias may increase the variance, or even the mea...

  17. Estimates of bias and uncertainty in recorded external dose

    International Nuclear Information System (INIS)

    Fix, J.J.; Gilbert, E.S.; Baumgartner, W.V.

    1994-10-01

    A study is underway to develop an approach to quantify bias and uncertainty in recorded dose estimates for workers at the Hanford Site based on personnel dosimeter results. This paper focuses on selected experimental studies conducted to better define response characteristics of Hanford dosimeters. The study is more extensive than the experimental studies presented in this paper and includes detailed consideration and evaluation of other sources of bias and uncertainty. Hanford worker dose estimates are used in epidemiologic studies of nuclear workers. A major objective of these studies is to provide a direct assessment of the carcinogenic risk of exposure to ionizing radiation at low doses and dose rates. Considerations of bias and uncertainty in the recorded dose estimates are important in the conduct of this work. The method developed for use with Hanford workers can be considered an elaboration of the approach used to quantify bias and uncertainty in estimated doses for personnel exposed to radiation as a result of atmospheric testing of nuclear weapons between 1945 and 1962. This approach was first developed by a National Research Council (NRC) committee examining uncertainty in recorded film badge doses during atmospheric tests (NRC 1989). It involved quantifying both bias and uncertainty from three sources (i.e., laboratory, radiological, and environmental) and then combining them to obtain an overall assessment. Sources of uncertainty have been evaluated for each of three specific Hanford dosimetry systems (i.e., the Hanford two-element film dosimeter, 1944-1956; the Hanford multi-element film dosimeter, 1957-1971; and the Hanford multi-element TLD, 1972-1993) used to estimate personnel dose throughout the history of Hanford operations. Laboratory, radiological, and environmental sources of bias and uncertainty have been estimated based on historical documentation and, for angular response, on selected laboratory measurements

  18. [Experimental research of gaits based on young plantar pressure test].

    Science.gov (United States)

    Meng, Qingyun; Tan, Shili; Yu, Hongliu; Shen, Lixing; Zhuang, Jianhai; Wang, Jinwu

    2014-10-01

    The present paper is to study the center line of the plantar pressure of normal young people, and to find the relation between center line of the plantar pressure and gait stability and balance. The paper gives the testing principle and calculating methods for geometric center of plantar pressure distribution and the center of pressure due to the techniques of footprint frame. The calculating formulas in both x direction and y direction are also deduced in the paper. In the experiments carried out in our laboratory, the gait parameters of 131 young subjects walking as usual speed were acquired, and 14 young subjects of the total were specially analyzed. We then provided reference data for the walking gait database of young people, including time parameters, space parameters and plantar pressure parameters. We also obtained the line of geometry center and pressure center under the foot. We found that the differences existed in normal people's geometric center line and the pressure center line. The center of pressure trajectory revealed foot movement stability. The length and lateral changes of the center line of the plantar pressure could be applied to analysis of the plantar pressure of all kinds of people. The results in this paper are useful in clinical foot disease diagnosis and evaluation of surgical effect.

  19. Efficacy testing and market research for the pork industry

    Science.gov (United States)

    Sivinski, Jacek S.

    Low dose (less than 30 krad) gamma irradiation of Trichinella spiralis infected pork renders the parasites sexually sterile and blocks maturation of the ingested larvae in the host gut. Irradiation of freshly slaughtered, market weight hog carcasses indicate that larvae throughout the carcass have essentially identical sensitivities to radiation. The research data indicate that 30 krad of 0.66 MeV gammas can be delivered to market weight, split carcasses with acceptable uniformity, and that such a dose can provide a substantial margin of safety for human consumption of even heavily infected meat. Feasibility studies of pork irradiation in commercial operations have shown the process to be technically, economically, and financially feasible. Treatment during the first four years of operation in a 2,000 hog per day plant will cost about 0.0034 dollars per pound and 0.0011 dollars per pound thereafter. Social and political feasibility are addressed in a 1,000-family consumer survey completed in the first quarter of 1984.

  20. Biosensors for GMO Testing: Nearly 25 Years of Research.

    Science.gov (United States)

    Sánchez-Paniagua López, Marta; Manzanares-Palenzuela, Carmen Lorena; López-Ruiz, Beatriz

    2018-09-03

    In the nearly two decades since genetically modified organisms (GMOs) were first commercialized, genetically engineered crops have gained ground on their conventional counterparts, reaching 185 million hectares worldwide in 2016. The technology has bestowed most of its benefits on enhancing crop productivity with two main traits currently dominating the market: insect-resistant and herbicide-tolerant crops. Despite their rapid and vast adoption by farmers worldwide, GMOs have generated heated debates, especially in European countries (EU), driven mostly by consumers concerned about safety of transgenic foods and about the potential impact on the environment. The need to monitor and to verify the presence and the amount of GMOs in agricultural crops and in food products has generated interest in analytical methods for sensitive, accurate, rapid, and cheap detection of these products. DNA biosensors have been envisioned as a novel DNA-detection technology that would one day substitute current amplification-based methods, providing hand-held, quick, and ultrasensitive gene-level detection. This review summarizes the contributions made in nearly 20 years of research regarding the application of genosensing technology for the qualitative and quantitative determination of transgenic traits.

  1. Efficacy testing and market research for the pork industry

    International Nuclear Information System (INIS)

    Sivinski, J.S.

    1985-01-01

    Low dose (less than 30 krad) gamma irradiation of Trichinella spiralis infected pork renders the parasites sexually sterile and blocks maturation of the ingested larvae in the host gut. Irradiation of freshly slaughtered, market weight hog carcasses indicate that larvae throughout the carcass have essentially identical sensitivities to radiation. The research data indicate that 30 krad of 0.66 MeV gammas can be delivered to market weight, split carcasses with acceptable uniformity, and that such a dose can provide a substantial margin of safety for human consumption of even heavily infected meat. Feasibility studies of pork irradiation in commercial operations have shown the process to be technically, economically, and financially feasible. Treatment during the first four years of operation in a 2,000 hog per day plant will cost about 0.0034 dollars per pound and 0.0011 dollars per pound thereafter. Social and political feasibility are addressed in a 1,000-family consumer survey completed in the first quarter of 1984. (author)

  2. Refurbish research and test reactors corresponding to global age of nuclear energy

    International Nuclear Information System (INIS)

    Mishima, Kaichiro; Oyama, Yukio; Okamoto, Koji; Yamana, Hajime; Yamaguchi, Akira

    2011-01-01

    This special article featured arguments for refurbishment of research and test reactors corresponding to global age of nuclear energy, based on the report: 'Investigation of research facilities necessary for future joint usage' issued by the special committee of Atomic Energy Society of Japan (AESJ) in September 2010. It consisted of six papers titled as 'Introduction-establishment of AESJ special committee for investigation', 'State of research and test reactors in Japan', 'State of overseas research and test reactors', 'Needs analysis for research and test reactors', 'Proposal of AESJ special committee' and 'Summary and future issues'. In order to develop human resources and promote research and development needed in global age of nuclear energy, research and test reactors would be refurbished as an Asian regional center of excellence. (T. Tanaka)

  3. Red Blood Cell Mechanical Fragility Test for Clinical Research Applications.

    Science.gov (United States)

    Ziegler, Luke A; Olia, Salim E; Kameneva, Marina V

    2017-07-01

    Red blood cell (RBC) susceptibility to mechanically induced hemolysis, or RBC mechanical fragility (MF), is an important parameter in the characterization of erythrocyte membrane health. The rocker bead test (RBT) and associated calculated mechanical fragility index (MFI) is a simple method for the assessment of RBC MF. Requiring a minimum of 15.5 mL of blood and necessitating adjustment of hematocrit (Ht) to a "standard" value (40%), the current RBT is not suitable for use in most studies involving human subjects. To address these limitations, we propose a 6.5 mL reduced volume RBT and corresponding modified MFI (MMFI) that does not require prior Ht adjustment. This new method was assessed for i) correlation to the existing text, ii) to quantify the effect of Ht on MFI, and iii) validation by reexamining the protective effect of plasma proteins on RBC MF. The reduced volume RBT strongly correlated (r = 0.941) with the established large volume RBT at matched Hts, and an equation was developed to calculate MMFI: a numerical estimation (R 2  = 0.923) of MFI if performed with the reduced volume RBT at "standard" (40%) Ht. An inversely proportional relationship was found between plasma protein concentration and RBC MF using the MMFI-reduced volume method, supporting previous literature findings. The new reduced volume RBT and modified MFI will allow for the measurement of RBC MF in clinical and preclinical studies involving humans or small animals. © 2017 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  4. Supply Inventory Management: Property Accountability at Research , Development, Test, and Evaluation Installations

    National Research Council Canada - National Science Library

    2002-01-01

    .... This report evaluates the Military Departments' improvement in maintaining property accountability over personal property at research, development, test, and evaluation installations, Personal...

  5. Trends in hypothesis testing and related variables in nursing research: a retrospective exploratory study.

    Science.gov (United States)

    Lash, Ayhan Aytekin; Plonczynski, Donna J; Sehdev, Amikar

    2011-01-01

    To compare the inclusion and the influences of selected variables on hypothesis testing during the 1980s and 1990s. In spite of the emphasis on conducting inquiry consistent with the tenets of logical positivism, there have been no studies investigating the frequency and patterns of hypothesis testing in nursing research The sample was obtained from the journal Nursing Research which was the research journal with the highest circulation during the study period under study. All quantitative studies published during the two decades including briefs and historical studies were included in the analyses A retrospective design was used to select the sample. Five years from the 1980s and 1990s each were randomly selected from the journal, Nursing Research. Of the 582 studies, 517 met inclusion criteria. Findings suggest that there has been a decline in the use of hypothesis testing in the last decades of the 20th century. Further research is needed to identify the factors that influence the conduction of research with hypothesis testing. Hypothesis testing in nursing research showed a steady decline from the 1980s to 1990s. Research purposes of explanation, and prediction/ control increased the likelihood of hypothesis testing. Hypothesis testing strengthens the quality of the quantitative studies, increases the generality of findings and provides dependable knowledge. This is particularly true for quantitative studies that aim to explore, explain and predict/control phenomena and/or test theories. The findings also have implications for doctoral programmes, research preparation of nurse-investigators, and theory testing.

  6. Comparison of Parametric and Nonparametric Methods for Analyzing the Bias of a Numerical Model

    Directory of Open Access Journals (Sweden)

    Isaac Mugume

    2016-01-01

    Full Text Available Numerical models are presently applied in many fields for simulation and prediction, operation, or research. The output from these models normally has both systematic and random errors. The study compared January 2015 temperature data for Uganda as simulated using the Weather Research and Forecast model with actual observed station temperature data to analyze the bias using parametric (the root mean square error (RMSE, the mean absolute error (MAE, mean error (ME, skewness, and the bias easy estimate (BES and nonparametric (the sign test, STM methods. The RMSE normally overestimates the error compared to MAE. The RMSE and MAE are not sensitive to direction of bias. The ME gives both direction and magnitude of bias but can be distorted by extreme values while the BES is insensitive to extreme values. The STM is robust for giving the direction of bias; it is not sensitive to extreme values but it does not give the magnitude of bias. The graphical tools (such as time series and cumulative curves show the performance of the model with time. It is recommended to integrate parametric and nonparametric methods along with graphical methods for a comprehensive analysis of bias of a numerical model.

  7. Using Multiple Control Groups and Matching to Address Unobserved Biases in Comparative Effectiveness Research: An Observational Study of the Effectiveness of Mental Health Parity.

    Science.gov (United States)

    Yoon, Frank B; Huskamp, Haiden A; Busch, Alisa B; Normand, Sharon-Lise T

    2011-06-21

    Studies of large policy interventions typically do not involve randomization. Adjustments, such as matching, can remove the bias due to observed covariates, but residual confounding remains a concern. In this paper we introduce two analytical strategies to bolster inferences of the effectiveness of policy interventions based on observational data. First, we identify how study groups may differ and then select a second comparison group on this source of difference. Second, we match subjects using a strategy that finely balances the distributions of key categorical covariates and stochastically balances on other covariates. An observational study of the effect of parity on the severely ill subjects enrolled in the Federal Employees Health Benefits (FEHB) Program illustrates our methods.

  8. Network Structure and Biased Variance Estimation in Respondent Driven Sampling.

    Science.gov (United States)

    Verdery, Ashton M; Mouw, Ted; Bauldry, Shawn; Mucha, Peter J

    2015-01-01

    This paper explores bias in the estimation of sampling variance in Respondent Driven Sampling (RDS). Prior methodological work on RDS has focused on its problematic assumptions and the biases and inefficiencies of its estimators of the population mean. Nonetheless, researchers have given only slight attention to the topic of estimating sampling variance in RDS, despite the importance of variance estimation for the construction of confidence intervals and hypothesis tests. In this paper, we show that the estimators of RDS sampling variance rely on a critical assumption that the network is First Order Markov (FOM) with respect to the dependent variable of interest. We demonstrate, through intuitive examples, mathematical generalizations, and computational experiments that current RDS variance estimators will always underestimate the population sampling variance of RDS in empirical networks that do not conform to the FOM assumption. Analysis of 215 observed university and school networks from Facebook and Add Health indicates that the FOM assumption is violated in every empirical network we analyze, and that these violations lead to substantially biased RDS estimators of sampling variance. We propose and test two alternative variance estimators that show some promise for reducing biases, but which also illustrate the limits of estimating sampling variance with only partial information on the underlying population social network.

  9. Research Problems Associated with Limiting the Applied Force in Vibration Tests and Conducting Base-Drive Modal Vibration Tests

    Science.gov (United States)

    Scharton, Terry D.

    1995-01-01

    The intent of this paper is to make a case for developing and conducting vibration tests which are both realistic and practical (a question of tailoring versus standards). Tests are essential for finding things overlooked in the analyses. The best test is often the most realistic test which can be conducted within the cost and budget constraints. Some standards are essential, but the author believes more in the individual's ingenuity to solve a specific problem than in the application of standards which reduce problems (and technology) to their lowest common denominator. Force limited vibration tests and base-drive modal tests are two examples of realistic, but practical testing approaches. Since both of these approaches are relatively new, a number of interesting research problems exist, and these are emphasized herein.

  10. Dwalingen in de methodologie. II. Bias door vragenlijsten

    DEFF Research Database (Denmark)

    Pouwer, F; Van Der Ploeg, Henk M; Bramsen, I

    1998-01-01

    Some characteristics of self-report questionnaires can result in bias in responding. When a test item or a questionnaire is biased, the observed scores form an imprecise measurement of reality as a consequence of systematic errors of measurement. Causes of such bias are: unclear instructions, vague...

  11. Stakeholder integrated research (STIR): a new approach tested in climate change adaptation research

    NARCIS (Netherlands)

    Gramberger, M.; Zellmer, K.; Kok, K.; Metzger, M.J.

    2015-01-01

    Ensuring active participation of stakeholders in scientific projects faces many challenges. These range from adequately selecting stakeholders, overcoming stakeholder fatigue, and dealing with the limited time available for stakeholder engagement, to interacting with, and integrating, the research

  12. Bias aware Kalman filters

    DEFF Research Database (Denmark)

    Drecourt, J.-P.; Madsen, H.; Rosbjerg, Dan

    2006-01-01

    This paper reviews two different approaches that have been proposed to tackle the problems of model bias with the Kalman filter: the use of a colored noise model and the implementation of a separate bias filter. Both filters are implemented with and without feedback of the bias into the model state....... The colored noise filter formulation is extended to correct both time correlated and uncorrelated model error components. A more stable version of the separate filter without feedback is presented. The filters are implemented in an ensemble framework using Latin hypercube sampling. The techniques...... are illustrated on a simple one-dimensional groundwater problem. The results show that the presented filters outperform the standard Kalman filter and that the implementations with bias feedback work in more general conditions than the implementations without feedback. 2005 Elsevier Ltd. All rights reserved....

  13. 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.

  14. Imaging the neural effects of cognitive bias modification training

    NARCIS (Netherlands)

    Wiers, C.E.; Wiers, R.W.

    Cognitive bias modification (CBM) was first developed as an experimental tool to examine the causal role of cognitive biases, and later developed into complementary interventions in experimental psychopathology research. CBM involves the "re-training" of implicit biases by means of multiple trials

  15. A Principal Components Analysis of Dynamic Spatial Memory Biases

    Science.gov (United States)

    Motes, Michael A.; Hubbard, Timothy L.; Courtney, Jon R.; Rypma, Bart

    2008-01-01

    Research has shown that spatial memory for moving targets is often biased in the direction of implied momentum and implied gravity, suggesting that representations of the subjective experiences of these physical principles contribute to such biases. The present study examined the association between these spatial memory biases. Observers viewed…

  16. The Analysis of a Teacher Test Preparation Tutorial to Learner Test Scores: An Action Research Study

    Science.gov (United States)

    Mild, Toni L. Hittle

    2014-01-01

    Many Pennsylvania colleges and universities require that teacher candidates pass a standardized assessment in order to gain formal entry in to their education programs. Standardized tests are also required for Level I teacher certification within Pennsylvania. The initial assessment required of all Pennsylvania preservice teachers for…

  17. Stochastic order in dichotomous item response models for fixed tests, research adaptive tests, or multiple abilities

    NARCIS (Netherlands)

    van der Linden, Willem J.

    1995-01-01

    Dichotomous item response theory (IRT) models can be viewed as families of stochastically ordered distributions of responses to test items. This paper explores several properties of such distributiom. The focus is on the conditions under which stochastic order in families of conditional

  18. Basophil activation test: food challenge in a test tube or specialist research tool?

    Science.gov (United States)

    Santos, Alexandra F; Lack, Gideon

    2016-01-01

    Oral food challenge (OFC) is the gold-standard to diagnose food allergy; however, it is a labour and resource-intensive procedure with the risk of causing an acute allergic reaction, which is potentially severe. Therefore, OFC are reserved for cases where the clinical history and the results of skin prick test and/or specific IgE do not confirm or exclude the diagnosis of food allergy. This is a significant proportion of patients seen in Allergy clinics and results in a high demand for OFC. The basophil activation test (BAT) has emerged as a new diagnostic test for food allergy. With high diagnostic accuracy, it can be particularly helpful in the cases where skin prick test and specific IgE are equivocal and may allow reducing the need for OFC. BAT has high specificity, which confers a high degree of certainty in confirming the diagnosis of food allergy and allows deferring the performance of OFC in patients with a positive BAT. The diagnostic utility of BAT is allergen-specific and needs to be validated for different allergens and in specific patient populations. Standardisation of the laboratory methodology and of the data analyses would help to enable a wider clinical application of BAT.

  19. Australia's Bond Home Bias

    OpenAIRE

    Anil V. Mishra; Umaru B. Conteh

    2014-01-01

    This paper constructs the float adjusted measure of home bias and explores the determinants of bond home bias by employing the International Monetary Fund's high quality dataset (2001 to 2009) on cross-border bond investment. The paper finds that Australian investors' prefer investing in countries with higher economic development and more developed bond markets. Exchange rate volatility appears to be an impediment for cross-border bond investment. Investors prefer investing in countries with ...

  20. Report of test and research results on atomic energy obtained in national institutes in fiscal 1983

    International Nuclear Information System (INIS)

    1984-01-01

    As for the test and research on the utilization of atomic energy by national organizations, the budget was appropriated for the first time in fiscal year 1956. Since then, many valuable results of research have been produced in the diverse fields of nuclear fusion, safety research, food irradiation, medicine and others, in this way, the test and research have played large roles in the promotion of the utilization of atomic energy in Japan. This is the 24th report, in which the results of the test and research on the utilization of atomic energy carried out in fiscal year 1983 by national organizations are summarized. 5 researches on nuclear fusion, 19 researches on engineering safety and environmental radioactivity safety, 3 researches on food irradiation, 6 researches on the countermeasures to cancer, 19 researches on agriculture, forestry and fishery, 30 researches on medicine, pharmaceuticals and environmental hygiene, 6 researches on mining and industry, 6 researches on power reactors and nuclear ships, 1 research on agricultural water, 7 researches on activation analysis and 4 researches on injury prevention are reported. (Kako, I.)

  1. 48 CFR 225.7016 - Restriction on Ballistic Missile Defense research, development, test, and evaluation.

    Science.gov (United States)

    2010-10-01

    ... Missile Defense research, development, test, and evaluation. 225.7016 Section 225.7016 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE SOCIOECONOMIC PROGRAMS... Acquisition 225.7016 Restriction on Ballistic Missile Defense research, development, test, and evaluation. [68...

  2. 78 FR 63971 - Notice of Availability of Record of Decision for Outdoor Research, Development, Test and...

    Science.gov (United States)

    2013-10-25

    ... DEPARTMENT OF DEFENSE Department of the Navy Notice of Availability of Record of Decision for Outdoor Research, Development, Test and Evaluation Activities at Naval Surface Warfare Center, Dahlgren... (NSWCDD) outdoor research, development, test and evaluation (RDT&E) activities within the Potomac River...

  3. On the Borders of Harmful and Helpful Beauty Biases

    OpenAIRE

    Maria Agthe; Maria Strobel; Matthias Spörrle; Michaela Pfundmair; Jon K. Maner

    2016-01-01

    Research with European Caucasian samples demonstrates that attractiveness-based biases in social evaluation depend on the constellation of the sex of the evaluator and the sex of the target: Whereas people generally show positive biases toward attractive opposite-sex persons, they show less positive or even negative biases toward attractive same-sex persons. By examining these biases both within and between different ethnicities, the current studies provide new evidence for both the generaliz...

  4. Effectiveness of Item Response Theory (IRT) Proficiency Estimation Methods under Adaptive Multistage Testing. Research Report. ETS RR-15-11

    Science.gov (United States)

    Kim, Sooyeon; Moses, Tim; Yoo, Hanwook Henry

    2015-01-01

    The purpose of this inquiry was to investigate the effectiveness of item response theory (IRT) proficiency estimators in terms of estimation bias and error under multistage testing (MST). We chose a 2-stage MST design in which 1 adaptation to the examinees' ability levels takes place. It includes 4 modules (1 at Stage 1, 3 at Stage 2) and 3 paths…

  5. Configuration management issues and objectives for a real-time research flight test support facility

    Science.gov (United States)

    Yergensen, Stephen; Rhea, Donald C.

    1988-01-01

    Presented are some of the critical issues and objectives pertaining to configuration management for the NASA Western Aeronautical Test Range (WATR) of Ames Research Center. The primary mission of the WATR is to provide a capability for the conduct of aeronautical research flight test through real-time processing and display, tracking, and communications systems. In providing this capability, the WATR must maintain and enforce a configuration management plan which is independent of, but complimentary to, various research flight test project configuration management systems. A primary WATR objective is the continued development of generic research flight test project support capability, wherein the reliability of WATR support provided to all project users is a constant priority. Therefore, the processing of configuration change requests for specific research flight test project requirements must be evaluated within a perspective that maintains this primary objective.

  6. An investigation of tropical Atlantic bias in a high-resolution coupled regional climate model

    Energy Technology Data Exchange (ETDEWEB)

    Patricola, Christina M.; Saravanan, R.; Hsieh, Jen-Shan [Texas A and M University, Department of Atmospheric Sciences, College Station, TX (United States); Li, Mingkui; Xu, Zhao [Texas A and M University, Department of Oceanography, College Station, TX (United States); Ocean University of China, Key Laboratory of Physical Oceanography of Ministry of Education, Qingdao (China); Chang, Ping [Texas A and M University, Department of Oceanography, College Station, TX (United States); Ocean University of China, Key Laboratory of Physical Oceanography of Ministry of Education, Qingdao (China); Second Institute of Oceanography, State Key Laboratory of Satellite Ocean Environment Dynamics, Hangzhou, Zhejiang (China)

    2012-11-15

    Coupled atmosphere-ocean general circulation models (AOGCMs) commonly fail to simulate the eastern equatorial Atlantic boreal summer cold tongue and produce a westerly equatorial trade wind bias. This tropical Atlantic bias problem is investigated with a high-resolution (27-km atmosphere represented by the Weather Research and Forecasting Model, 9-km ocean represented by the Regional Ocean Modeling System) coupled regional climate model. Uncoupled atmospheric simulations test climate sensitivity to cumulus, land-surface, planetary boundary layer, microphysics, and radiation parameterizations and reveal that the radiation scheme has a pronounced impact in the tropical Atlantic. The CAM radiation simulates a dry precipitation (up to -90%) and cold land-surface temperature (up to -8 K) bias over the Amazon related to an over-representation of low-level clouds and almost basin-wide westerly trade wind bias. The Rapid Radiative Transfer Model and Goddard radiation simulates doubled Amazon and Congo Basin precipitation rates and a weak eastern Atlantic trade wind bias. Season-long high-resolution coupled regional model experiments indicate that the initiation of the warm eastern equatorial Atlantic sea surface temperature (SST) bias is more sensitive to the local rather than basin-wide trade wind bias and to a wet Congo Basin instead of dry Amazon - which differs from AOGCM simulations. Comparisons between coupled and uncoupled simulations suggest a regional Bjerknes feedback confined to the eastern equatorial Atlantic amplifies the initial SST, wind, and deepened thermocline bias, while barrier layer feedbacks are relatively unimportant. The SST bias in some CRCM simulations resembles the typical AOGCM bias indicating that increasing resolution is unlikely a simple solution to this problem. (orig.)

  7. Reducing status quo bias in choice experiments

    DEFF Research Database (Denmark)

    Bonnichsen, Ole; Ladenburg, Jacob

    In stated preference literature, the tendency to choose the alternative representing the status quo situation seems to exceed real life status quo effects. Accordingly, status quo bias can be a problem. In Choice Experiments, status quo bias is found to be strongly correlated with protest attitudes...... toward the cost attribute. If economic values are to be elicited, this problem is difficult to remedy. In a split sample framework we test a novel ex-ante entreaty aimed specifically at the cost attribute and find that it effectively reduces status quo bias and improves the internal validity...

  8. Recent Advances in Attention Bias Modification for Substance Addictions

    Directory of Open Access Journals (Sweden)

    Melvyn Weibin Zhang

    2018-04-01

    Full Text Available Research on attentional bias modification has increased since 2014. A recent meta-analysis demonstrates evidence for bias modification for substance disorders, including alcohol and tobacco use disorders. Several pharmacological trials have shown that pharmacological agents can attenuate and modify such attentional bias. The pharmacological trials that have appeared to date have produced mixed results, which has clinical implications. Developments in Internet and mobile technologies have transformed how attention bias modification is currently being achieved. There remains great potential for further research that examines the efficacy of technology-aided attention bias interventions.

  9. Bias During the Evaluation of Animal Studies?

    Directory of Open Access Journals (Sweden)

    Andrew Knight

    2012-02-01

    Full Text Available My recent book entitled The Costs and Benefits of Animal Experiments seeks to answer a key question within animal ethics, namely: is animal experimentation ethically justifiable? Or, more precisely, is it justifiable within the utilitarian cost:benefit framework that fundamentally underpins most regulations governing animal experimentation? To answer this question I reviewed more than 500 scientific publications describing animal studies, animal welfare impacts, and alternative research, toxicity testing and educational methodologies. To minimise bias I focused primarily on large-scale systematic reviews that had examined the human clinical and toxicological utility of animal studies. Despite this, Dr. Susanne Prankel recently reviewed my book in this journal, essentially accusing me of bias. However, she failed to provide any substantive evidence to refute my conclusions, let alone evidence of similar weight to that on which they are based. Those conclusions are, in fact, firmly based on utilitarian ethical reasoning, informed by scientific evidence of considerable strength, and I believe they are robust.

  10. Does neurocognitive function affect cognitive bias toward an emotional stimulus? Association between general attentional ability and attentional bias toward threat

    OpenAIRE

    Hakamata, Yuko; Matsui, Mie; Tagaya, Hirokuni

    2014-01-01

    Background: Although poorer cognitive performance has been found to be associated with anxiety, it remains unclear whether neurocognitive function affects biased cognitive processing toward emotional information. We investigated whether general cognitive function evaluated with a standard neuropsychological test predicts biased cognition, focusing on attentional bias toward threat. Methods: One hundred and five healthy young adults completed a dot-probe task measuring attentional bias and ...

  11. Research on the improvement of nuclear safety -Thermal hydraulic tests for reactor safety system-

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Moon Kee; Park, Choon Kyung; Yang, Sun Kyoo; Chun, Se Yung; Song, Chul Hwa; Jun, Hyung Kil; Jung, Heung Joon; Won, Soon Yun; Cho, Yung Roh; Min, Kyung Hoh; Jung, Jang Hwan; Jang, Suk Kyoo; Kim, Bok Deuk; Kim, Wooi Kyung; Huh, Jin; Kim, Sook Kwan; Moon, Sang Kee; Lee, Sang Il [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1995-06-01

    The present research aims at the development of the thermal hydraulic verification test technology for the safety system of the conventional and advanced nuclear power plant and the development of the advanced thermal hydraulic measuring techniques. In this research, test facilities simulating the primary coolant system and safety system are being constructed for the design verification tests of the existing and advanced nuclear power plant. 97 figs, 14 tabs, 65 refs. (Author).

  12. Testing painted wood : past practices at the Forest Products Laboratory and recommendations for future research

    Science.gov (United States)

    R. Sam Williams

    2009-01-01

    A brief history of paint research at the Forest Products Laboratory (FPL) in Madison, Wisconsin, sets the stage for a discussion of testing paint on wood and wood products. Tests include laboratory and outdoor tests, and I discuss them in terms of several degradation mechanisms (loss of gloss and fading, mildew growth, extractives bleed, and cracking, flaking, and...

  13. Results of single borehole hydraulic testing in the Mizunami Underground Research Laboratory project. Phase 2

    International Nuclear Information System (INIS)

    Daimaru, Shuji; Takeuchi, Ryuji; Onoe, Hironori; Saegusa, Hiromitsu

    2012-09-01

    This report summarize the results of the single borehole hydraulic tests of 79 sections conducted as part of the Construction phase (Phase 2) in the Mizunami Underground Research Laboratory (MIU) Project. The details of each test (test interval depth, geology, etc.) as well as the interpreted hydraulic parameters and analytical method used are presented in this report. (author)

  14. FJ44 Turbofan Engine Test at NASA Glenn Research Center's Aero-Acoustic Propulsion Laboratory

    Science.gov (United States)

    Lauer, Joel T.; McAllister, Joseph; Loew, Raymond A.; Sutliff, Daniel L.; Harley, Thomas C.

    2009-01-01

    A Williams International FJ44-3A 3000-lb thrust class turbofan engine was tested in the NASA Glenn Research Center s Aero-Acoustic Propulsion Laboratory. This report presents the test set-up and documents the test conditions. Farfield directivity, in-duct unsteady pressures, duct mode data, and phased-array data were taken and are reported separately.

  15. Test Anxiety Research: Students with Vision Impairments and Students with Mild Intellectual Disabilities

    Science.gov (United States)

    Datta, Poulomee

    2014-01-01

    There is an absence of research on test anxiety in students with disabilities although such testing is taken for granted among students without disabilities. This study investigated the test anxiety of the students in each of the two disability groups, those with vision impairments and those with intellectual disabilities who are placed in…

  16. Students' gender bias in teaching evaluations

    Directory of Open Access Journals (Sweden)

    Narissra Punyanunt-Carter

    2015-09-01

    Full Text Available The goal of this study was to investigate if there is gender bias in student evaluations. Researchers administered a modified version of the teacher evaluation forms to 58 students (male=30; female=28 in a basic introductory communications class. Half the class was instructed to fill out the survey about a male professor, and the other half a female professor. Researchers broke down the evaluation results question by question in order to give a detailed account of the findings. Results revealed that there is certainly some gender bias at work when students evaluate their instructors. It was also found that gender bias does not significantly affect the evaluations. The results align with other findings in the available literature, which point to some sort of pattern regarding gender bias in evaluations, but it still seems to be inconsequential.  DOI: 10.18870/hlrc.v5i3.234

  17. Initial Flight Test of the Production Support Flight Control Computers at NASA Dryden Flight Research Center

    Science.gov (United States)

    Carter, John; Stephenson, Mark

    1999-01-01

    The NASA Dryden Flight Research Center has completed the initial flight test of a modified set of F/A-18 flight control computers that gives the aircraft a research control law capability. The production support flight control computers (PSFCC) provide an increased capability for flight research in the control law, handling qualities, and flight systems areas. The PSFCC feature a research flight control processor that is "piggybacked" onto the baseline F/A-18 flight control system. This research processor allows for pilot selection of research control law operation in flight. To validate flight operation, a replication of a standard F/A-18 control law was programmed into the research processor and flight-tested over a limited envelope. This paper provides a brief description of the system, summarizes the initial flight test of the PSFCC, and describes future experiments for the PSFCC.

  18. Assistance in MSD Research and Development: Part 1, Small scale research, development and testing: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Worsey, P.N.; Canon, C.

    1988-03-01

    The development and testing of a simple mechanical stemming aid is described. The aid comprises a solid unit placed in the stemming above the explosive column and is designed to improve blasting efficiency and reduce drilling and blasting costs. It is designed to work with back filled drill cuttings or any other suitable stemming material. To date it has consisted of the testing of the aid in small diameter (1.5 and 1.625 inch) holes in Jefferson City Dolomite for both bench and crater blasting configurations. Full scale field trials are being conducted nearby in similar rock in an aggregate quarry. The data acquisition equipment used in Phase 1 included both a Spin Physics SP2000 high speed video motion analysis system and acoustic and seismic monitoring units. Measurements for each test included peak air over pressure, ground surface ppv, stemming displacement and velocity and face movement and extent. The results illustrate that the concept is sound and that its successful application to production blasting at full scale will be a function of manufacturing cost, the development of suitable insertion techniques for large diameter boreholes and the selection of a suitable low cost material for the aid. 17 refs., 20 figs.

  19. Cognitive bias modification and CBT as early interventions for adolescent social and test anxiety : Two-year follow-up of a randomized controlled trial

    NARCIS (Netherlands)

    de Hullu, Eva; Sportel, B. Esther; Nauta, Maaike H.; de Jong, Peter J.

    Background and Objectives: This two-year follow-up study evaluated the long-term outcomes of two early interventions that aimed at reducing social and test anxiety in young adolescents at risk for developing social anxiety disorder. Methods: In this RCP, moderately socially anxious adolescents

  20. Attentional bias in snus users: an experimental study.

    Directory of Open Access Journals (Sweden)

    Rune Aune Mentzoni

    Full Text Available The use of nicotine in the form of "snus" is substantial and increasing in some geographic areas, in particular among young people. It has previously been suggested that addictions may operate through a mechanism of attentional bias, in which stimuli representative of the dependent substance increase in salience, thus increasing the addictive behavior. However, this hypothesis has not been tested for the case of snus. The current experiment used a modified Stroop task and a dot-probe task to investigate whether 40 snus users show an attentional bias towards snus-relevant stimuli, compared to 40 non-snus users. There were no significant differences between the two groups on reaction times or accuracy on either Stroop or dot-probe task, thus failing to show an attentional bias towards snus-relevant stimuli for snus users. This could imply that other mechanisms may contribute to maintenance of snus use than for other addictions. However, this is the first experimental study investigating attentional bias in snus users, and more research is warranted.

  1. Influential Cognitive Processes on Framing Biases in Aging

    Directory of Open Access Journals (Sweden)

    Alison M. Perez

    2018-05-01

    Full Text Available Factors that contribute to overcoming decision-making biases in later life pose an important investigational question given the increasing older adult population. Limited empirical evidence exists and the literature remains equivocal of whether increasing age is associated with elevated susceptibility to decision-making biases such as framing effects. Research into the individual differences contributing to decision-making ability may offer better understanding of the influence of age in decision-making ability. Changes in cognition underlying decision-making have been shown with increased age and may contribute to individual variability in decision-making abilities. This study had three aims; (1 to understand the influence of age on susceptibility to decision-making biases as measured by framing effects across a large, continuous age range; (2 to examine influence of cognitive abilities that change with age; and (3 to understand the influence of individual factors such as gender and education on susceptibility to framing effects. 200 individuals (28–79 years of age were tested on a large battery of cognitive measures in the domains of executive function, memory and complex attention. Findings from this study demonstrated that cognitive abilities such as strategic control and delayed memory better predicted susceptibility to framing biases than age. The current findings demonstrate that age may not be as influential a factor in decision-making as cognitive ability and cognitive reserve. These findings motivate future studies to better characterize cognitive ability to determine decision-making susceptibilities in aging populations.

  2. Influential Cognitive Processes on Framing Biases in Aging.

    Science.gov (United States)

    Perez, Alison M; Spence, Jeffrey Scott; Kiel, L D; Venza, Erin E; Chapman, Sandra B

    2018-01-01

    Factors that contribute to overcoming decision-making biases in later life pose an important investigational question given the increasing older adult population. Limited empirical evidence exists and the literature remains equivocal of whether increasing age is associated with elevated susceptibility to decision-making biases such as framing effects. Research into the individual differences contributing to decision-making ability may offer better understanding of the influence of age in decision-making ability. Changes in cognition underlying decision-making have been shown with increased age and may contribute to individual variability in decision-making abilities. This study had three aims; (1) to understand the influence of age on susceptibility to decision-making biases as measured by framing effects across a large, continuous age range; (2) to examine influence of cognitive abilities that change with age; and (3) to understand the influence of individual factors such as gender and education on susceptibility to framing effects. 200 individuals (28-79 years of age) were tested on a large battery of cognitive measures in the domains of executive function, memory and complex attention. Findings from this study demonstrated that cognitive abilities such as strategic control and delayed memory better predicted susceptibility to framing biases than age. The current findings demonstrate that age may not be as influential a factor in decision-making as cognitive ability and cognitive reserve. These findings motivate future studies to better characterize cognitive ability to determine decision-making susceptibilities in aging populations.

  3. Influential Cognitive Processes on Framing Biases in Aging

    Science.gov (United States)

    Perez, Alison M.; Spence, Jeffrey Scott; Kiel, L. D.; Venza, Erin E.; Chapman, Sandra B.

    2018-01-01

    Factors that contribute to overcoming decision-making biases in later life pose an important investigational question given the increasing older adult population. Limited empirical evidence exists and the literature remains equivocal of whether increasing age is associated with elevated susceptibility to decision-making biases such as framing effects. Research into the individual differences contributing to decision-making ability may offer better understanding of the influence of age in decision-making ability. Changes in cognition underlying decision-making have been shown with increased age and may contribute to individual variability in decision-making abilities. This study had three aims; (1) to understand the influence of age on susceptibility to decision-making biases as measured by framing effects across a large, continuous age range; (2) to examine influence of cognitive abilities that change with age; and (3) to understand the influence of individual factors such as gender and education on susceptibility to framing effects. 200 individuals (28–79 years of age) were tested on a large battery of cognitive measures in the domains of executive function, memory and complex attention. Findings from this study demonstrated that cognitive abilities such as strategic control and delayed memory better predicted susceptibility to framing biases than age. The current findings demonstrate that age may not be as influential a factor in decision-making as cognitive ability and cognitive reserve. These findings motivate future studies to better characterize cognitive ability to determine decision-making susceptibilities in aging populations. PMID:29867641

  4. Present status and future perspectives of research and test reactor in Japan

    International Nuclear Information System (INIS)

    Kaneko, Yoshihiko; Kaieda, Keisuke

    2000-01-01

    Since 1957, Japan Atomic Energy Research Institute (JAERI) has constructed several research and test reactors to fulfill a major role in the study of nuclear energy and fundamental research. At present four reactors, the Japan Research Reactor No. 3 and No. 4 (JRR-3M and JRR-4 respectively), the Japan Materials Testing Reactor (JMTR) and the Nuclear Safety Research Reactor (NSRR) are in operation, and a new High Temperature Engineering Test Reactor (HTTR) has recently reached first criticality and now in the power up test. In 1966, the Kyoto University built the Kyoto University Reactor (KUR) and started its operation for joint use program of the Japanese universities. This paper introduces these reactors and describes their present operational status and also efforts for aging management. The recent tendency of utilization and future perspectives is also reported. (author)

  5. Present status and future perspectives of research and test reactor in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Kaneko, Yoshihiko [Atomic Energy Research Laboratory, Musashi Institute of Technology, Kawasaki, Kanagawa (Japan); Kaieda, Keisuke [Department of Research Reactor, Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan)

    2000-10-01

    Since 1957, Japan Atomic Energy Research Institute (JAERI) has constructed several research and test reactors to fulfill a major role in the study of nuclear energy and fundamental research. At present four reactors, the Japan Research Reactor No. 3 and No. 4 (JRR-3M and JRR-4 respectively), the Japan Materials Testing Reactor (JMTR) and the Nuclear Safety Research Reactor (NSRR) are in operation, and a new High Temperature Engineering Test Reactor (HTTR) has recently reached first criticality and now in the power up test. In 1966, the Kyoto University built the Kyoto University Reactor (KUR) and started its operation for joint use program of the Japanese universities. This paper introduces these reactors and describes their present operational status and also efforts for aging management. The recent tendency of utilization and future perspectives is also reported. (author)

  6. Study for improvement of performance of the test and research reactors

    Energy Technology Data Exchange (ETDEWEB)

    Sakurai, Fumio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1999-03-01

    Current utilization needs for the test and research reactors become more advanced and diversified along with the advance of nuclear science and technology. Besides, the requested safety for the research and test reactors grows strictly every year as well as a case of the power reactors. Under this circumstance, every effort to improve reactor performance including its safety is necessary to be sustained for allowing more effective utilization of the test and research reactors as experimental apparatus for advanced researches. In this study, the following three themes i.e., JMTR high-performance fuel element, evaluation method of fast neutron irradiation dose in the JMTR, evaluation method of performance of siphon break valve as core covering system for water-cooled test and research reactors, were investigated respectively from the views of improvement of core performance as a neutron source, utilization performance as an experimental apparatus, and safety as a reactor plant. (author)

  7. Opinion dynamics with confirmation bias.

    Directory of Open Access Journals (Sweden)

    Armen E Allahverdyan

    Full Text Available Confirmation bias is the tendency to acquire or evaluate new information in a way that is consistent with one's preexisting beliefs. It is omnipresent in psychology, economics, and even scientific practices. Prior theoretical research of this phenomenon has mainly focused on its economic implications possibly missing its potential connections with broader notions of cognitive science.We formulate a (non-Bayesian model for revising subjective probabilistic opinion of a confirmationally-biased agent in the light of a persuasive opinion. The revision rule ensures that the agent does not react to persuasion that is either far from his current opinion or coincides with it. We demonstrate that the model accounts for the basic phenomenology of the social judgment theory, and allows to study various phenomena such as cognitive dissonance and boomerang effect. The model also displays the order of presentation effect-when consecutively exposed to two opinions, the preference is given to the last opinion (recency or the first opinion (primacy -and relates recency to confirmation bias. Finally, we study the model in the case of repeated persuasion and analyze its convergence properties.The standard Bayesian approach to probabilistic opinion revision is inadequate for describing the observed phenomenology of persuasion process. The simple non-Bayesian model proposed here does agree with this phenomenology and is capable of reproducing a spectrum of effects observed in psychology: primacy-recency phenomenon, boomerang effect and cognitive dissonance. We point out several limitations of the model that should motivate its future development.

  8. Measuring Agricultural Bias

    DEFF Research Database (Denmark)

    Jensen, Henning Tarp; Robinson, Sherman; Tarp, Finn

    The measurement issue is the key issue in the literature on trade policy-induced agri-cultural price incentive bias. This paper introduces a general equilibrium effective rate of protection (GE-ERP) measure, which extends and generalizes earlier partial equilibrium nominal protection measures...... 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....... 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...

  9. Cylindrical core reflood test facility (CCTF) and slab core reflood test facility (SCTF) for Japan Atomic Energy Research Institute (JAERI)

    International Nuclear Information System (INIS)

    1981-01-01

    IHI has designed and constructed the CCTF at JAERI to be used in the safety analysis research on the loss of coolant accident in a PWR plant. This test facility is planned so that reflood phenomenon in the PWR plant (a phenomenon is that the bared and overheated core is reflooded by the emergency core cooling system when the coolant loss accident occurred) is simulated under various test conditions. The CCTF is the largest-scale test plant in the world, composed of approximately 2000 simulated fuel rods (electric heaters), 1 simulated pressure vessel, 4 primary cooling loops, 2 simulated steam generators, emergency core cooling system, and so on. The test conditions are controlled, and the test steps are sequentially progressed by the computing system, and test data are collected by the data acquisition system. Furthermore, IHI is now designing and constructing the SCTF in accordance with the JAERI research plan. The SCTF is similar to the CCTF in scale. Main feature of the SCTF is the form of the simulated core and the simulated pressure vessel, which is of slab construction to be representative of the radial section of the PWR reactor. Reliable and various data for safety analysis are expected by the CCTF and the SCTF. (author)

  10. The Testing Behind The Test Facility: The Acoustic Design of the NASA Glenn Research Center's World-Class Reverberant Acoustic Test Facility

    Science.gov (United States)

    Hozman, Aron D.; Hughes, William O.; McNelis, Mark E.; McNelis, Anne M.

    2011-01-01

    The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) is leading the design and build of the new world-class vibroacoustic test capabilities at the NASA GRC's Plum Brook Station in Sandusky, Ohio, USA. Benham Companies, LLC is currently constructing modal, base-shake sine and reverberant acoustic test facilities to support the future testing needs of NASA's space exploration program. The large Reverberant Acoustic Test Facility (RATF) will be approximately 101,000 cu ft in volume and capable of achieving an empty chamber acoustic overall sound pressure level (OASPL) of 163 dB. This combination of size and acoustic power is unprecedented amongst the world's known active reverberant acoustic test facilities. The key to achieving the expected acoustic test spectra for a range of many NASA space flight environments in the RATF is the knowledge gained from a series of ground acoustic tests. Data was obtained from several NASA-sponsored test programs, including testing performed at the National Research Council of Canada's acoustic test facility in Ottawa, Ontario, Canada, and at the Redstone Technical Test Center acoustic test facility in Huntsville, Alabama, USA. The majority of these tests were performed to characterize the acoustic performance of the modulators (noise generators) and representative horns that would be required to meet the desired spectra, as well as to evaluate possible supplemental gas jet noise sources. The knowledge obtained in each of these test programs enabled the design of the RATF sound generation system to confidently advance to its final acoustic design and subsequent on-going construction.

  11. The t-test: An Influential Inferential Tool in Chaplaincy and Other Healthcare Research.

    Science.gov (United States)

    Jankowski, Katherine R B; Flannelly, Kevin J; Flannelly, Laura T

    2018-01-01

    The t-test developed by William S. Gosset (also known as Student's t-test and the two-sample t-test) is commonly used to compare one sample mean on a measure with another sample mean on the same measure. The outcome of the t-test is used to draw inferences about how different the samples are from each other. It is probably one of the most frequently relied upon statistics in inferential research. It is easy to use: a researcher can calculate the statistic with three simple tools: paper, pen, and a calculator. A computer program can quickly calculate the t-test for large samples. The ease of use can result in the misuse of the t-test. This article discusses the development of the original t-test, basic principles of the t-test, two additional types of t-tests (the one-sample t-test and the paired t-test), and recommendations about what to consider when using the t-test to draw inferences in research.

  12. The laboratory test rig with miniature jet engine to research aviation fuels combustion process

    Directory of Open Access Journals (Sweden)

    Gawron Bartosz

    2015-12-01

    Full Text Available This article presents laboratory test rig with a miniature turbojet engine (MiniJETRig – Miniature Jet Engine Test Rig, that was built in the Air Force Institute of Technology. The test rig has been developed for research and development works aimed at modelling and investigating processes and phenomena occurring in full scale jet engines. In the article construction of a test rig is described, with a brief discussion on the functionality of each of its main components. Additionally examples of measurement results obtained during the realization of the initial tests have been included, presenting the capabilities of the test rig.

  13. Toward a synthesis of cognitive biases: how noisy information processing can bias human decision making.

    Science.gov (United States)

    Hilbert, Martin

    2012-03-01

    A single coherent framework is proposed to synthesize long-standing research on 8 seemingly unrelated cognitive decision-making biases. During the past 6 decades, hundreds of empirical studies have resulted in a variety of rules of thumb that specify how humans systematically deviate from what is normatively expected from their decisions. Several complementary generative mechanisms have been proposed to explain those cognitive biases. Here it is suggested that (at least) 8 of these empirically detected decision-making biases can be produced by simply assuming noisy deviations in the memory-based information processes that convert objective evidence (observations) into subjective estimates (decisions). An integrative framework is presented to show how similar noise-based mechanisms can lead to conservatism, the Bayesian likelihood bias, illusory correlations, biased self-other placement, subadditivity, exaggerated expectation, the confidence bias, and the hard-easy effect. Analytical tools from information theory are used to explore the nature and limitations that characterize such information processes for binary and multiary decision-making exercises. The ensuing synthesis offers formal mathematical definitions of the biases and their underlying generative mechanism, which permits a consolidated analysis of how they are related. This synthesis contributes to the larger goal of creating a coherent picture that explains the relations among the myriad of seemingly unrelated biases and their potential psychological generative mechanisms. Limitations and research questions are discussed.

  14. Selecting the most appropriate inferential statistical test for your quantitative research study.

    Science.gov (United States)

    Bettany-Saltikov, Josette; Whittaker, Victoria Jane

    2014-06-01

    To discuss the issues and processes relating to the selection of the most appropriate statistical test. A review of the basic research concepts together with a number of clinical scenarios is used to illustrate this. Quantitative nursing research generally features the use of empirical data which necessitates the selection of both descriptive and statistical tests. Different types of research questions can be answered by different types of research designs, which in turn need to be matched to a specific statistical test(s). Discursive paper. This paper discusses the issues relating to the selection of the most appropriate statistical test and makes some recommendations as to how these might be dealt with. When conducting empirical quantitative studies, a number of key issues need to be considered. Considerations for selecting the most appropriate statistical tests are discussed and flow charts provided to facilitate this process. When nursing clinicians and researchers conduct quantitative research studies, it is crucial that the most appropriate statistical test is selected to enable valid conclusions to be made. © 2013 John Wiley & Sons Ltd.

  15. [The research protocol VI: How to choose the appropriate statistical test. Inferential statistics].

    Science.gov (United States)

    Flores-Ruiz, Eric; Miranda-Novales, María Guadalupe; Villasís-Keever, Miguel Ángel

    2017-01-01

    The statistical analysis can be divided in two main components: descriptive analysis and inferential analysis. An inference is to elaborate conclusions from the tests performed with the data obtained from a sample of a population. Statistical tests are used in order to establish the probability that a conclusion obtained from a sample is applicable to the population from which it was obtained. However, choosing the appropriate statistical test in general poses a challenge for novice researchers. To choose the statistical test it is necessary to take into account three aspects: the research design, the number of measurements and the scale of measurement of the variables. Statistical tests are divided into two sets, parametric and nonparametric. Parametric tests can only be used if the data show a normal distribution. Choosing the right statistical test will make it easier for readers to understand and apply the results.

  16. Irradiation Tests Supporting LEU Conversion of Very High Power Research Reactors in the US

    Energy Technology Data Exchange (ETDEWEB)

    Woolstenhulme, N. E.; Cole, J. I.; Glagolenko, I.; Holdaway, K. K.; Housley, G. K.; Rabin, B. H.

    2016-10-01

    The US fuel development team is developing a high density uranium-molybdenum alloy monolithic fuel to enable conversion of five high-power research reactors. Previous irradiation tests have demonstrated promising behavior for this fuel design. A series of future irradiation tests will enable selection of final fuel fabrication process and provide data to qualify the fuel at moderately-high power conditions for use in three of these five reactors. The remaining two reactors, namely the Advanced Test Reactor and High Flux Isotope Reactor, require additional irradiation tests to develop and demonstrate the fuel’s performance with even higher power conditions, complex design features, and other unique conditions. This paper reviews the program’s current irradiation testing plans for these moderately-high irradiation conditions and presents conceptual testing strategies to illustrate how subsequent irradiation tests will build upon this initial data package to enable conversion of these two very-high power research reactors.

  17. The research protocol VI: How to choose the appropriate statistical test. Inferential statistics

    Directory of Open Access Journals (Sweden)

    Eric Flores-Ruiz

    2017-10-01

    Full Text Available The statistical analysis can be divided in two main components: descriptive analysis and inferential analysis. An inference is to elaborate conclusions from the tests performed with the data obtained from a sample of a population. Statistical tests are used in order to establish the probability that a conclusion obtained from a sample is applicable to the population from which it was obtained. However, choosing the appropriate statistical test in general poses a challenge for novice researchers. To choose the statistical test it is necessary to take into account three aspects: the research design, the number of measurements and the scale of measurement of the variables. Statistical tests are divided into two sets, parametric and nonparametric. Parametric tests can only be used if the data show a normal distribution. Choosing the right statistical test will make it easier for readers to understand and apply the results.

  18. Attachment insecurity, biased perceptions of romantic partners' negative emotions, and hostile relationship behavior.

    Science.gov (United States)

    Overall, Nickola C; Fletcher, Garth J O; Simpson, Jeffry A; Fillo, Jennifer

    2015-05-01

    In the current research, we tested the extent to which attachment insecurity produces inaccurate and biased perceptions of intimate partners' emotions and whether more negative perceptions of partners' emotions elicit the damaging behavior often associated with attachment insecurity. Perceptions of partners' emotions as well as partners' actual emotions were assessed multiple times in couples' conflict discussions (Study 1) and daily during a 3-week period in 2 independent samples (Study 2). Using partners' reports of their own emotional experiences as the accuracy benchmark, we simultaneously tested whether attachment insecurity was associated with the degree to which individuals (a) accurately detected shifts in their partners' negative emotions (tracking accuracy), and (b) perceived their partners were feeling more negative relationship-related emotions than they actually experienced (directional bias). Highly avoidant perceivers were equally accurate at tracking their partners' changing emotions compared to less avoidant individuals (tracking accuracy), but they overestimated the intensity of their partners' negative emotions to a greater extent than less avoidant individuals (directional bias). In addition, more negative perceptions of partners' emotions triggered more hostile and defensive behavior in highly avoidant perceivers both during conflict discussions (Study 1) and in daily life (Study 2). In contrast, attachment anxiety was not associated with tracking accuracy, directional bias, or hostile reactions to perceptions of their partners' negative emotions. These findings demonstrate the importance of assessing biased perceptions in actual relationship interactions and reveal that biased perceptions play an important role in activating the defenses of avoidantly attached people. (c) 2015 APA, all rights reserved).

  19. Positively Biased Self-Perceptions of Peer Acceptance and Subtypes of Aggression in Children

    Science.gov (United States)

    Lynch, Rebecca J.; Kistner, Janet A.; Stephens, Haley F.; David-Ferdon, Corinne

    2016-01-01

    There is a growing body of research linking children’s positively biased self-perceptions with higher levels of aggression. This study extended this area of research by examining prospective associations of positively biased self-perceptions of peer acceptance with overt and relational aggression. In addition, moderating effects of peer rejection were examined to test the “disputed overestimation hypothesis,” which posits that the link between bias and aggression is limited to children who are rejected by their peers. Using a two-wave longitudinal design, measures of peer-rated and self-perceived peer acceptance and peer-rated overt and relational aggression were obtained for 712 children in 3rd through 5th grades (386 girls and 326 boys). Positively biased perceptions led to increases in relational, but not overt, aggression. This pattern was observed even when the effects of gender, race, peer rejection, and overt aggression on relational aggression were controlled. Contrary to the disputed overestimation hypothesis, the prospective associations between bias and aggression did not vary as a function of children’s peer rejection status, thus supporting the view that positive bias predicts future aggressive behavior, regardless of social status. The results are discussed in terms of the comparability with previous findings and practical implications. PMID:26423823

  20. Development and pilot test of a process to identify research needs from a systematic review.

    Science.gov (United States)

    Saldanha, Ian J; Wilson, Lisa M; Bennett, Wendy L; Nicholson, Wanda K; Robinson, Karen A

    2013-05-01

    To ensure appropriate allocation of research funds, we need methods for identifying high-priority research needs. We developed and pilot tested a process to identify needs for primary clinical research using a systematic review in gestational diabetes mellitus. We conducted eight steps: abstract research gaps from a systematic review using the Population, Intervention, Comparison, Outcomes, and Settings (PICOS) framework; solicit feedback from the review authors; translate gaps into researchable questions using the PICOS framework; solicit feedback from multidisciplinary stakeholders at our institution; establish consensus among multidisciplinary external stakeholders on the importance of the research questions using the Delphi method; prioritize outcomes; develop conceptual models to highlight research needs; and evaluate the process. We identified 19 research questions. During the Delphi method, external stakeholders established consensus for 16 of these 19 questions (15 with "high" and 1 with "medium" clinical benefit/importance). We pilot tested an eight-step process to identify clinically important research needs. Before wider application of this process, it should be tested using systematic reviews of other diseases. Further evaluation should include assessment of the usefulness of the research needs generated using this process for primary researchers and funders. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. Context matters: volunteer bias, small sample size, and the value of comparison groups in the assessment of research-based undergraduate introductory biology lab courses.

    Science.gov (United States)

    Brownell, Sara E; Kloser, Matthew J; Fukami, Tadashi; Shavelson, Richard J

    2013-01-01

    The shift from cookbook to authentic research-based lab courses in undergraduate biology necessitates the need for evaluation and assessment of these novel courses. Although the biology education community has made progress in this area, it is important that we interpret the effectiveness of these courses with caution and remain mindful of inherent limitations to our study designs that may impact internal and external validity. The specific context of a research study can have a dramatic impact on the conclusions. We present a case study of our own three-year investigation of the impact of a research-based introductory lab course, highlighting how volunteer students, a lack of a comparison group, and small sample sizes can be limitations of a study design that can affect the interpretation of the effectiveness of a course.

  2. Context Matters: Volunteer Bias, Small Sample Size, and the Value of Comparison Groups in the Assessment of Research-Based Undergraduate Introductory Biology Lab Courses

    Directory of Open Access Journals (Sweden)

    Sara E. Brownell

    2013-08-01

    Full Text Available The shift from cookbook to authentic research-based lab courses in undergraduate biology necessitates the need for evaluation and assessment of these novel courses. Although the biology education community has made progress in this area, it is important that we interpret the effectiveness of these courses with caution and remain mindful of inherent limitations to our study designs that may impact internal and external validity. The specific context of a research study can have a dramatic impact on the conclusions. We present a case study of our own three-year investigation of the impact of a research-based introductory lab course, highlighting how volunteer students, a lack of a comparison group, and small sample sizes can be limitations of a study design that can affect the interpretation of the effectiveness of a course.

  3. Thermal hydraulic tests for reactor safety system -Research on the improvement of nuclear safety-

    International Nuclear Information System (INIS)

    Chung, Moon Ki; Park, Chun Kyeong; Yang, Seon Kyu; Chung, Chang Hwan; Chun, Shee Yeong; Song, Cheol Hwa; Chun, Hyeong Gil; Chang, Seok Kyu; Chung, Heung Joon; Won, Soon Yeon; Cho, Yeong Ro; Kim, Bok Deuk; Min, Kyeong Ho

    1994-07-01

    The present research aims at the development of the thermal hydraulic verification test technology for the reactor safety system of the conventional and advanced nuclear power plant and the development of the advanced thermal hydraulic measuring techniques. (Author)

  4. Static pile load tests on driven piles in Intermediate-Geo Materials : research brief.

    Science.gov (United States)

    2017-02-01

    Research Objectives: : Investigate the use of modified standard penetration tests (MSPT) : Compare field results with predictions made by the WisDOT driving formula, PDA and CAPWAP : Improve prediction of pile lengths and pile capacities ...

  5. Performance Test for Neutron Detector and Associated System using Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Seongwoo; Park, Sung Jae; Cho, Man Soon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Oh, Se Hyun [USERS, Daejeon (Korea, Republic of); Shin, Ho Cheol [KHNP CRI, Daejeon (Korea, Republic of)

    2016-10-15

    SPND (Self-Powered Neutron Detector) has been developed to extend its lifespan. ENFMS (Ex-Core Flux Monitoring System) of pressurized water reactor has been also improved. After the development and improvement, their performance must be verified under the neutron irradiation environment. We used a research reactor for the performance verification of neutron detector and associated system because the research reactor can meet the neutron flux level of commercial nuclear reactor. In this paper, we report the performance verification method and result for the SPND and ENFMS using the research reactor. The performance tests for the SPND and ENFMS were conducted using UCI TRIGA reactor. The test environment of commercial reactor’s neutron flux level must be required. However, it is difficult to perform the test in the commercial rector due to the constraint of time and space. The research reactor can be good alternative neutron source for the test of neutron detectors and associated system.

  6. 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...

  7. Stimulus-driven attention, threat bias, and sad bias in youth with a history of an anxiety disorder or depression

    Science.gov (United States)

    Sylvester, Chad M.; Hudziak, James J.; Gaffrey, Michael S.; Barch, Deanna M.; Luby, Joan L.

    2015-01-01

    Attention biases towards threatening and sad stimuli are associated with pediatric anxiety and depression, respectively. The basic cognitive mechanisms associated with attention biases in youth, however, remain unclear. Here, we tested the hypothesis that threat bias (selective attention for threatening versus neutral stimuli) but not sad bias relies on stimulus-driven attention. We collected measures of stimulus-driven attention, threat bias, sad bias, and current clinical symptoms in youth with a history of an anxiety disorder and/or depression (ANX/DEP; n=40) as well as healthy controls (HC; n=33). Stimulus-driven attention was measured with a non-emotional spatial orienting task, while threat bias and sad bias were measured at a short time interval (150 ms) with a spatial orienting task using emotional faces and at a longer time interval (500 ms) using a dot-probe task. In ANX/DEP but not HC, early attention bias towards threat was negatively correlated with later attention bias to threat, suggesting that early threat vigilance was associated with later threat avoidance. Across all subjects, stimulus-driven orienting was not correlated with early threat bias but was negatively correlated with later threat bias, indicating that rapid stimulus-driven orienting is linked to later threat avoidance. No parallel relationships were detected for sad bias. Current symptoms of depression but not anxiety were related to decreased stimulus-driven attention. Together, these results are consistent with the hypothesis that threat bias but not sad bias relies on stimulus-driven attention. These results inform the design of attention bias modification programs that aim to reverse threat biases and reduce symptoms associated with pediatric anxiety and depression. PMID:25702927

  8. Stimulus-Driven Attention, Threat Bias, and Sad Bias in Youth with a History of an Anxiety Disorder or Depression.

    Science.gov (United States)

    Sylvester, Chad M; Hudziak, James J; Gaffrey, Michael S; Barch, Deanna M; Luby, Joan L

    2016-02-01

    Attention biases towards threatening and sad stimuli are associated with pediatric anxiety and depression, respectively. The basic cognitive mechanisms associated with attention biases in youth, however, remain unclear. Here, we tested the hypothesis that threat bias (selective attention for threatening versus neutral stimuli) but not sad bias relies on stimulus-driven attention. We collected measures of stimulus-driven attention, threat bias, sad bias, and current clinical symptoms in youth with a history of an anxiety disorder and/or depression (ANX/DEP; n = 40) as well as healthy controls (HC; n = 33). Stimulus-driven attention was measured with a non-emotional spatial orienting task, while threat bias and sad bias were measured at a short time interval (150 ms) with a spatial orienting task using emotional faces and at a longer time interval (500 ms) using a dot-probe task. In ANX/DEP but not HC, early attention bias towards threat was negatively correlated with later attention bias to threat, suggesting that early threat vigilance was associated with later threat avoidance. Across all subjects, stimulus-driven orienting was not correlated with early threat bias but was negatively correlated with later threat bias, indicating that rapid stimulus-driven orienting is linked to later threat avoidance. No parallel relationships were detected for sad bias. Current symptoms of depression but not anxiety were related to decreased stimulus-driven attention. Together, these results are consistent with the hypothesis that threat bias but not sad bias relies on stimulus-driven attention. These results inform the design of attention bias modification programs that aim to reverse threat biases and reduce symptoms associated with pediatric anxiety and depression.

  9. Empirical Benchmarks of Hidden Bias in Educational Research: Implication for Assessing How well Propensity Score Methods Approximate Experiments and Conducting Sensitivity Analysis

    Science.gov (United States)

    Dong, Nianbo; Lipsey, Mark

    2014-01-01

    When randomized control trials (RCT) are not feasible, researchers seek other methods to make causal inference, e.g., propensity score methods. One of the underlined assumptions for the propensity score methods to obtain unbiased treatment effect estimates is the ignorability assumption, that is, conditional on the propensity score, treatment…

  10. Research ethics across the 49th parallel: the potential value of pilot testing "equivalent protections" in Canadian research institutions.

    Science.gov (United States)

    Lavery, James V; McDonald, Michael; Meslin, Eric M

    2005-01-01

    Canada and the United States share the world's largest trade partnership and an increasing concern about divergent regulatory approaches to common industries. Canadian research institutes receive more research funding from the U.S. National Institutes of Health than any other country, much of it to fund multi-centre and collaborative research between the two countries. Because of these close economic and research ties, and the extensive similarities between the two countries in the review and oversight of ethics in human subjects research, we propose that Canada would be an ideal country for a pilot-test of the feasibility of "equivalent protections," a U.S. regulation that permits comparison of protections for human subjects between institutions in the two countries. The "equivalent protections" has been advocated by various bodies in the United States as a potentially beneficial mechanism for improving oversight of foreign trials. As well, we argue that "equivalent protections" could prove to be valuable for Canada in five specific ways: (1) by potentially reducing administrative burden on Canadian research institutions administering U.S. federal research funding; (2) by creating symbolic value of an explicit recognition by the United States that procedures normally followed for the protection of human subjects in Canadian research institutions are at least equivalent to those provided by the U.S. regulations; (3) by lowering the opportunity cost of investing in research in Canada; (4) by affording Canada an opportunity to enhance its leadership role in international research by offering an alternative to the U.S. regulatory model for the protection of human subjects; and (5) by providing a model for how the idea of equivalent protections might be addressed for research funded by Canadian agencies but conducted in other countries.

  11. Examining Gender Bias in Studies of Innovation

    OpenAIRE

    Crowden, N.

    2003-01-01

    This paper examines the presence of a gender bias in studies of innovation. Using the Innovation Systems Research Network (ISRN) and its interview guide as a case study, this research project examines how accurately and completely such innovation studies present gender differences in the innovation process.

  12. Reward sensitivity, attentional bias, and executive control in early adolescent alcohol use.

    Science.gov (United States)

    van Hemel-Ruiter, Madelon E; de Jong, Peter J; Ostafin, Brian D; Wiers, Reinout W

    2015-01-01

    This study examined whether attentional bias for alcohol stimuli was associated with alcohol use in young adolescents, and whether the frequently demonstrated relationship between reward sensitivity and adolescent alcohol use would be partly mediated by attentional bias for alcohol cues. In addition, this study investigated the potential moderating role of executive control (EC), and tested whether the relationship between alcohol-related attentional bias and alcohol use was especially present in young adolescents with weak EC. Participants were 86 adolescents (mean age=14.86), who completed a Visual Probe Task (VPT) as an index of attentional bias, a flanker-task based Attention Network Task (ANT) as an index of EC, the sensitivity of punishment and sensitivity of reward questionnaire (SPSRQ) as an index of reward sensitivity, and an alcohol use questionnaire. High reward sensitivity, high alcohol-related attentional bias, and weak EC were all related to alcohol use. The relationship between reward sensitivity and alcohol use was not mediated by alcohol-related attentional bias. As hypothesized, attentional bias was only associated with alcohol use in participants with weak EC. Together, the present findings are consistent with the view that high reward sensitivity and low EC may be considered as risk factors for adolescent alcohol use. The independent contribution of reward sensitivity and attentional bias might suggest that adolescents who are highly reward sensitive and display an attentional bias for alcohol cues are at even higher risk for excessive alcohol use and developing alcohol abuse problems. Future research using a longitudinal approach would allow an examination of these risk factors on subsequent alcohol use. Treatment implications are discussed, including the importance of strengthening EC and reducing the rewarding value of alcohol use. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Cognitive Bias in the Verification and Validation of Space Flight Systems

    Science.gov (United States)

    Larson, Steve

    2012-01-01

    Cognitive bias is generally recognized as playing a significant role in virtually all domains of human decision making. Insight into this role is informally built into many of the system engineering practices employed in the aerospace industry. The review process, for example, typically has features that help to counteract the effect of bias. This paper presents a discussion of how commonly recognized biases may affect the verification and validation process. Verifying and validating a system is arguably more challenging than development, both technically and cognitively. Whereas there may be a relatively limited number of options available for the design of a particular aspect of a system, there is a virtually unlimited number of potential verification scenarios that may be explored. The probability of any particular scenario occurring in operations is typically very difficult to estimate, which increases reliance on judgment that may be affected by bias. Implementing a verification activity often presents technical challenges that, if they can be overcome at all, often result in a departure from actual flight conditions (e.g., 1-g testing, simulation, time compression, artificial fault injection) that may raise additional questions about the meaningfulness of the results, and create opportunities for the introduction of additional biases. In addition to mitigating the biases it can introduce directly, the verification and validation process must also overcome the cumulative effect of biases introduced during all previous stages of development. A variety of cognitive biases will be described, with research results for illustration. A handful of case studies will be presented that show how cognitive bias may have affected the verification and validation process on recent JPL flight projects, identify areas of strength and weakness, and identify potential changes or additions to commonly used techniques that could provide a more robust verification and validation of

  14. Present status of mechanical testing technology at the Research Hot Laboratory

    International Nuclear Information System (INIS)

    Kizaki, M.; Tobita, T.; Koya, T.; Kikuchi, T.

    1993-01-01

    Mechanical tests of irradiated metallic materials at the Research Hot Laboratory(RHL) have been carried out for 30 years to support material research in JAERI and to evaluate the irradiation integrity of pressure vessel steel in commercial power plant. Two tensile testing machines and one Charpy impact testing machine are available for the examinations. One of the tensile testing machines has 1000 kgf load capacity under the vacuum of ∼ 10 -7 torr at the temperature of 1300degC max.. The other one has 10 tonf load capacity, and is utilized for the multi-purpose tests such as tensile and compressive tests in air atmosphere at the temperature between -160 and 900degC. Examinations cover tensile test, bending test, J ic fracture toughness test, low cycle fatigue test and so on. Charpy impact testing machine with notched-bar specimen is instrumented with 30 kgf-m capacity in the temperature range of -140 - 240 degC. To support these mechanical tests in RHL, special jigs, devices and instruments have been developed. (author)

  15. Beyond attentional bias: a perceptual bias in a dot-probe task.

    Science.gov (United States)

    Bocanegra, Bruno R; Huijding, Jorg; Zeelenberg, René

    2012-12-01

    Previous dot-probe studies indicate that threat-related face cues induce a bias in spatial attention. Independently of spatial attention, a recent psychophysical study suggests that a bilateral fearful face cue improves low spatial-frequency perception (LSF) and impairs high spatial-frequency perception (HSF). Here, we combine these separate lines of research within a single dot-probe paradigm. We found that a bilateral fearful face cue, compared with a bilateral neutral face cue, speeded up responses to LSF targets and slowed down responses to HSF targets. This finding is important, as it shows that emotional cues in dot-probe tasks not only bias where information is preferentially processed (i.e., an attentional bias in spatial location), but also bias what type of information is preferentially processed (i.e., a perceptual bias in spatial frequency). PsycINFO Database Record (c) 2012 APA, all rights reserved.

  16. Power ramp testing method for PWR fuel rod at research reactor

    International Nuclear Information System (INIS)

    Zhou Yidong; Zhang Peisheng; Zhang Aimin; Gao Yongguang; Wang Huarong

    2003-01-01

    A tentative power ramp test for short PWR fuel rod has been conducted at the Heavy Water Research Reactor (HWRR) in China Institute of Atomic Energy (CIAE). The test fuel rod was cooled by the circulating water in the test loop. The power ramp was realized by moving solid neutron-absorbing screen around the fuel rod. The linear power of the fuel rod increased from 220 W/cm to 340 W/cm with a power ramp rate of 20 W/cm/min. The power of the fuel rod was monitored by both in-core thermal and nuclear measurement sensors in the test rig. This test provides experiences for further developing the power ramp test methods for PWR fuel rods at research reactor. (author)

  17. Genetic Testing and Its Implications: Human Genetics Researchers Grapple with Ethical Issues.

    Science.gov (United States)

    Rabino, Isaac

    2003-01-01

    Contributes systematic data on the attitudes of scientific experts who engage in human genetics research about the pros, cons, and ethical implications of genetic testing. Finds that they are highly supportive of voluntary testing and the right to know one's genetic heritage. Calls for greater genetic literacy. (Contains 87 references.) (Author/NB)

  18. Research Note The reliability of a field test kit for the detection and ...

    African Journals Online (AJOL)

    Research Note The reliability of a field test kit for the detection and the persistence of ... Open Access DOWNLOAD FULL TEXT ... The objectives were to test a field kit for practicality and reliability, to assess the spread of the bacteria among ...

  19. Use of "t"-Test and ANOVA in Career-Technical Education Research

    Science.gov (United States)

    Rojewski, Jay W.; Lee, In Heok; Gemici, Sinan

    2012-01-01

    Use of t-tests and analysis of variance (ANOVA) procedures in published research from three scholarly journals in career and technical education (CTE) during a recent 5-year period was examined. Information on post hoc analyses, reporting of effect size, alpha adjustments to account for multiple tests, power, and examination of assumptions…

  20. Framing and bias in CO2 capture and storage communication films: Reflections from a CO2 capture and storage research group.

    Science.gov (United States)

    Maynard, Carly M; Shackley, Simon

    2017-03-01

    There has been a growing trend towards incorporating short, educational films as part of research funding and project proposals. Researchers and developers in CO 2 capture and storage are using films to communicate outcomes, but such films can be influenced by experiences and values of the producers. We document the content and presentation of seven online CO 2 capture and storage films to determine how framing occurs and its influence on the tone of films. The core frame presents CO 2 capture and storage as a potential solution to an imminent crisis in climatic warming and lack of a sustainable energy supply. Three subsidiary frames represent CO 2 capture and storage as (1) the only option, (2) a partial option or (3) a scientific curiosity. The results demonstrate that an understanding of the nuanced explicit and implicit messages portrayed by films is essential both for effective framing according to one's intention and for wider public understanding of a field.

  1. New Tools for New Literacies Research: An Exploration of Usability Testing Software

    Science.gov (United States)

    Asselin, Marlene; Moayeri, Maryam

    2010-01-01

    Competency in the new literacies of the Internet is essential for participating in contemporary society. Researchers studying these new literacies are recognizing the limitations of traditional methodological tools and adapting new technologies and new media for use in research. This paper reports our exploration of usability testing software to…

  2. Performance test of ex-core high temperature and high pressure water loop test equipment (Contract research)

    International Nuclear Information System (INIS)

    Nakano, Hiroko; Uehara, Toshiaki; Takeuchi, Tomoaki; Shibata, Hiroshi; Nakamura, Jinichi; Matsui, Yoshinori; Tsuchiya, Kunihiko

    2016-03-01

    In Japan Atomic Energy Agency, we started research and development so as to monitor the situations in the Nuclear Plant Facilities during a severe accident, such as a radiation-resistant monitoring camera, a radiation-resistant transmission system for conveying the in-core information, and a heat-resistant signal cable. As a part of developments of the heat-resistant signal cable, we prepared ex-core high-temperature and high-pressure water loop test equipment, which can simulate the conditions of BWRs and PWRs, for evaluating reliability and properties of sheath materials of the cable. This equipment consists of autoclave, water conditioning tank, high-pressure metering pump, preheater, heat exchanger and water purification equipment, etc. This report describes the basic design and the performance test results of ex-core high-temperature and high-pressure water loop test equipment. (author)

  3. Testing a model of research intention among U.K. clinical psychologists: a logistic regression analysis.

    Science.gov (United States)

    Eke, Gemma; Holttum, Sue; Hayward, Mark

    2012-03-01

    Previous research highlights barriers to clinical psychologists conducting research, but has rarely examined U.K. clinical psychologists. The study investigated U.K. clinical psychologists' self-reported research output and tested part of a theoretical model of factors influencing their intention to conduct research. Questionnaires were mailed to 1,300 U.K. clinical psychologists. Three hundred and seventy-four questionnaires were returned (29% response-rate). This study replicated in a U.K. sample the finding that the modal number of publications was zero, highlighted in a number of U.K. and U.S. studies. Research intention was bimodally distributed, and logistic regression classified 78% of cases successfully. Outcome expectations, perceived behavioral control and normative beliefs mediated between research training environment and intention. Further research should explore how research is negotiated in clinical roles, and this issue should be incorporated into prequalification training. © 2012 Wiley Periodicals, Inc.

  4. 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.

  5. Developing a 'Research Test Bed' to introduce innovative Emission Testing Technology to improve New Zealand's Vehicle Emission Standards

    International Nuclear Information System (INIS)

    Cox, Stephen J

    2012-01-01

    Vehicle exhaust emissions arise from the combustion of the fuel and air mixture in the engine. Exhaust emission gases generally include carbon monoxide (CO), oxides of nitrogen (NOx), hydrocarbons (HC), particulates, and the greenhouse gas carbon dioxide (CO2). In New Zealand improvements have occurred in emissions standards over the past 20 years however significant health related issues are now being discovered in Auckland as a direct effect of high vehicle emission levels. Pollution in New Zealand, especially via vehicle emissions are an increasing concern and threatens New Zealand's 'clean and green' image. Unitec Institute of Technology proposes establishing a Vehicle Emissions Testing Facility, and with an understanding with Auckland University, National Institute of Water and Atmosphere Research Ltd (NIWA) this research group can work collaboratively on vehicle emissions testing. New Zealand research providers would support an application in the UK led by the University of Huddersfield to a range of European Union Structural Funds. New Zealand has an ideal 'vehicle emissions research environment' supported by significant expertise in vehicle emission control technology and associated protocols at the University of Auckland, and the effects of high vehicle emissions on health at the National Institutes of Water and Atmosphere (NIWA).

  6. No sex-biased dispersal in a primate with an uncommon social system—cooperative polyandry

    Directory of Open Access Journals (Sweden)

    Samuel L. Díaz-Muñoz

    2014-10-01

    Full Text Available An influential hypothesis proposed by Greenwood (1980 suggests that different mating systems result in female and male-biased dispersal, respectively, in birds and mammals. However, other aspects of social structure and behavior can also shape sex-biased dispersal. Although sex-specific patterns of kin cooperation are expected to affect the benefits of philopatry and dispersal patterns, empirical evidence is scarce. Unlike many mammals, Saguinus geoffroyi (Geoffroy’s tamarin has a breeding system in which typically multiple males mate with a single breeding female. Males typically form cooperative reproductive partnerships between relatives, whereas females generally compete for reproductive opportunities. This system of cooperative polyandry is predicted to result in female-biased dispersal, providing an opportunity to test the current hypotheses of sex-biased dispersal. Here we test for evidence of sex-biased dispersal in S. geoffroyi using demographic and genetic data from three populations. We find no sex bias in natal dispersal, contrary to the prediction based on the mating patterns. This pattern was consistent after controlling for the effects of historical population structure. Limited breeding opportunities within social groups likely drive both males and females to disperse, suggesting that dispersal is intimately related to the social context. The integration of genetic and field data revealed that tamarins are another exception to the presumed pattern of male-biased dispersal in mammals. A shift in focus from mating systems to social behavior, which plays a role in most all processes expected to influence sex-bias in dispersal, will be a fruitful target for research both within species and across taxa.

  7. Basic research into eddy current testing of austenetic weld joints and surface claddings

    International Nuclear Information System (INIS)

    Meier, W.

    1976-01-01

    The result of research work has shown that the eddy-current testing method can be used for austenetic steel up to 10 mm thick to detect cracks in the material. An exception to this are laminations if they are parallel to the surface. Cracks in the various geometrical positions in the test specimen produce different results in the x-y plot. They are influenced by the direction of the material cracks. Research into the influence the geometric parameters have on the indications shows that the eddy-current method provides clearer interpretations of material cracks than any other non-destructive test method known. (orig.) [de

  8. Voting with their mice: personal genome testing and the "participatory turn" in disease research.

    Science.gov (United States)

    Prainsack, Barbara

    2011-05-01

    While the availability of genome tests on the internet has given rise to heated debates about the likely impact on personal genome information on test-takers, on insurance, and on healthcare systems, in this article I argue that a more tangible effect of personal genomics is that it has started to change how participation in disease research is conceived and enacted. I examine three models of research participation that personal genomics customers are encouraged to engage in. I conclude with an evaluation of the pitfalls and benefits of "crowdsourcing" genetic disease research in the context of personal genomics.

  9. Reflexive intergroup bias in third-party punishment.

    Science.gov (United States)

    Yudkin, Daniel A; Rothmund, Tobias; Twardawski, Mathias; Thalla, Natasha; Van Bavel, Jay J

    2016-11-01

    Humans show a rare tendency to punish norm-violators who have not harmed them directly-a behavior known as third-party punishment. Research has found that third-party punishment is subject to intergroup bias, whereby people punish members of the out-group more severely than the in-group. Although the prevalence of this behavior is well-documented, the psychological processes underlying it remain largely unexplored. Some work suggests that it stems from people's inherent predisposition to form alliances with in-group members and aggress against out-group members. This implies that people will show reflexive intergroup bias in third-party punishment, favoring in-group over out-group members especially when their capacity for deliberation is impaired. Here we test this hypothesis directly, examining whether intergroup bias in third-party punishment emerges from reflexive, as opposed to deliberative, components of moral cognition. In 3 experiments, utilizing a simulated economic game, we varied participants' group relationship to a transgressor, measured or manipulated the extent to which they relied on reflexive or deliberative judgment, and observed people's punishment decisions. Across group-membership manipulations (American football teams, nationalities, and baseball teams) and 2 assessments of reflexive judgment (response time and cognitive load), reflexive judgment heightened intergroup bias, suggesting that such bias in punishment is inherent to human moral cognition. We discuss the implications of these studies for theories of punishment, cooperation, social behavior, and legal practice. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  10. Cognitive biases can affect moral intuitions about cognitive enhancement

    Directory of Open Access Journals (Sweden)

    Lucius eCaviola

    2014-10-01

    Full Text Available Research into cognitive biases that impair human judgment has mostly been applied to the area of economic decision-making. Ethical decision-making has been comparatively neglected. Since ethical decisions often involve very high individual as well as collective stakes, analyzing how cognitive biases affect them can be expected to yield important results. In this theoretical article, we consider the ethical debate about cognitive enhancement (CE and suggest a number of cognitive biases that are likely to affect moral intuitions and judgments about CE: status quo bias, loss aversion, risk aversion, omission bias, scope insensitivity, nature bias, and optimistic bias. We find that there are more well-documented biases that are likely to cause irrational aversion to CE than biases in the opposite direction. This suggests that common attitudes about CE are predominantly negatively biased. Within this new perspective, we hope that subsequent research will be able to elaborate this hypothesis and develop effective de-biasing techniques that can help increase the rationality of the public CE debate and thus improve our ethical decision-making.

  11. A European collaboration research programme to study and test large scale base isolated structures

    International Nuclear Information System (INIS)

    Renda, V.; Verzeletti, G.; Papa, L.

    1995-01-01

    The improvement of the technology of innovative anti-seismic mechanisms, as those for base isolation and energy dissipation, needs of testing capability for large scale models of structures integrated with these mechanisms. These kind experimental tests are of primary importance for the validation of design rules and the setting up of an advanced earthquake engineering for civil constructions of relevant interest. The Joint Research Centre of the European Commission offers the European Laboratory for Structural Assessment located at Ispra - Italy, as a focal point for an international european collaboration research programme to test large scale models of structure making use of innovative anti-seismic mechanisms. A collaboration contract, opened to other future contributions, has been signed with the national italian working group on seismic isolation (Gruppo di Lavoro sull's Isolamento Sismico GLIS) which includes the national research centre ENEA, the national electricity board ENEL, the industrial research centre ISMES and producer of isolators ALGA. (author). 3 figs

  12. Rotary Balance Wind Tunnel Testing for the FASER Flight Research Aircraft

    Science.gov (United States)

    Denham, Casey; Owens, D. Bruce

    2016-01-01

    Flight dynamics research was conducted to collect and analyze rotary balance wind tunnel test data in order to improve the aerodynamic simulation and modeling of a low-cost small unmanned aircraft called FASER (Free-flying Aircraft for Sub-scale Experimental Research). The impetus for using FASER was to provide risk and cost reduction for flight testing of more expensive aircraft and assist in the improvement of wind tunnel and flight test techniques, and control laws. The FASER research aircraft has the benefit of allowing wind tunnel and flight tests to be conducted on the same model, improving correlation between wind tunnel, flight, and simulation data. Prior wind tunnel tests include a static force and moment test, including power effects, and a roll and yaw damping forced oscillation test. Rotary balance testing allows for the calculation of aircraft rotary derivatives and the prediction of steady-state spins. The rotary balance wind tunnel test was conducted in the NASA Langley Research Center (LaRC) 20-Foot Vertical Spin Tunnel (VST). Rotary balance testing includes runs for a set of given angular rotation rates at a range of angles of attack and sideslip angles in order to fully characterize the aircraft rotary dynamics. Tests were performed at angles of attack from 0 to 50 degrees, sideslip angles of -5 to 10 degrees, and non-dimensional spin rates from -0.5 to 0.5. The effects of pro-spin elevator and rudder deflection and pro- and anti-spin elevator, rudder, and aileron deflection were examined. The data are presented to illustrate the functional dependence of the forces and moments on angle of attack, sideslip angle, and angular rate for the rotary contributions to the forces and moments. Further investigation is necessary to fully characterize the control effectors. The data were also used with a steady state spin prediction tool that did not predict an equilibrium spin mode.

  13. Report of test and research results on atomic energy obtained in national institutes in fiscal 1985

    International Nuclear Information System (INIS)

    1986-01-01

    As for the test and research on the utilization of atomic energy in national institutes, the budget was appropriated for the first time in fiscal year 1956, and since then, the many valuable results of research have been obtained so far in the diversified fields of nuclear fusion, safety research, the irradiation of foods, medicine and others, thus the test and research accomplished the large role for promoting the utilization of atomic energy in Japan. In this report, the gists of the results of the test and research on the utilization of atomic energy carried out by national institutes in fiscal year 1985 are collected. No.1 of this report was published in 1960, and this is No.26. It is desired to increase the understanding about the recent trend and the results of the test and research on atomic energy utilization with this book. The researches on nuclear fusion, engineering safety and environmental radioactivity safety, the irradiation of foods, the countermeasures against cancer, fertilized soil, the quality improvement of brewing and farm products, the protection of farm products and the improvement of breeding, diagnosis and medical treatment, pharmaceuticals, environmental hygiene, the application to physiology and pathology, radiochemistry, radiation measurement, process analysis, nuclear reactor materials, nuclear powered ships, civil engineering, radioactivation analysis and injury prevention are reported. (Kako, I.)

  14. Research reactor fuel bundle design review by means of hydrodynamic testing

    International Nuclear Information System (INIS)

    Pastorini, A.; Belinco, C.

    1997-01-01

    During the design steps of a fuel bundle for a nuclear reactor, some vibration tests are usually necessary to verify the prototype dynamical response characteristics and the structural integrity. To perform these tests, the known hydrodynamic loop facilities are used to evaluate the vibrational response of the bundle under the different flow conditions that may appear in the reactor. This paper describes the tests performed on a 19 plate fuel bundle prototype designed for a low power research reactor. The tests were done in order to know the dynamical characteristics of the plates and also of the whole bundle under different flow rate conditions. The paper includes a description of the test facilities and the results obtained during the dynamical characterization tests and some preliminary comments about the tests under flowing water are also presented. (author) [es

  15. Asset Analysis and Operational Concepts for Separation Assurance Flight Testing at Dryden Flight Research Center

    Science.gov (United States)

    Costa, Guillermo J.; Arteaga, Ricardo A.

    2011-01-01

    A preliminary survey of existing separation assurance and collision avoidance advancements, technologies, and efforts has been conducted in order to develop a concept of operations for flight testing autonomous separation assurance at Dryden Flight Research Center. This effort was part of the Unmanned Aerial Systems in the National Airspace System project. The survey focused primarily on separation assurance projects validated through flight testing (including lessons learned), however current forays into the field were also examined. Comparisons between current Dryden flight and range assets were conducted using House of Quality matrices in order to allow project management to make determinations regarding asset utilization for future flight tests. This was conducted in order to establish a body of knowledge of the current collision avoidance landscape, and thus focus Dryden s efforts more effectively towards the providing of assets and test ranges for future flight testing within this research field.

  16. Systematic biases in human heading estimation.

    Directory of Open Access Journals (Sweden)

    Luigi F Cuturi

    Full Text Available Heading estimation is vital to everyday navigation and locomotion. Despite extensive behavioral and physiological research on both visual and vestibular heading estimation over more than two decades, the accuracy of heading estimation has not yet been systematically evaluated. Therefore human visual and vestibular heading estimation was assessed in the horizontal plane using a motion platform and stereo visual display. Heading angle was overestimated during forward movements and underestimated during backward movements in response to both visual and vestibular stimuli, indicating an overall multimodal bias toward lateral directions. Lateral biases are consistent with the overrepresentation of lateral preferred directions observed in neural populations that carry visual and vestibular heading information, including MSTd and otolith afferent populations. Due to this overrepresentation, population vector decoding yields patterns of bias remarkably similar to those observed behaviorally. Lateral biases are inconsistent with standard bayesian accounts which predict that estimates should be biased toward the most common straight forward heading direction. Nevertheless, lateral biases may be functionally relevant. They effectively constitute a perceptual scale expansion around straight ahead which could allow for more precise estimation and provide a high gain feedback signal to facilitate maintenance of straight-forward heading during everyday navigation and locomotion.

  17. The Development of the Acoustic Design of NASA Glenn Research Center's New Reverberant Acoustic Test Facility

    Science.gov (United States)

    Hughes, William O.; McNelis, Mark E.; Hozman, Aron D.; McNelis, Anne M.

    2011-01-01

    The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) is leading the design and build of the new world-class vibroacoustic test capabilities at the NASA GRC s Plum Brook Station in Sandusky, Ohio. Benham Companies, LLC is currently constructing modal, base-shake sine and reverberant acoustic test facilities to support the future testing needs of NASA s space exploration program. The large Reverberant Acoustic Test Facility (RATF) will be approximately 101,000 ft3 in volume and capable of achieving an empty chamber acoustic overall sound pressure level (OASPL) of 163 dB. This combination of size and acoustic power is unprecedented amongst the world s known active reverberant acoustic test facilities. The key to achieving the expected acoustic test spectra for a range of many NASA space flight environments in the RATF is the knowledge gained from a series of ground acoustic tests. Data was obtained from several NASA-sponsored test programs, including testing performed at the National Research Council of Canada s acoustic test facility in Ottawa, Ontario, Canada, and at the Redstone Technical Test Center acoustic test facility in Huntsville, Alabama. The majority of these tests were performed to characterize the acoustic performance of the modulators (noise generators) and representative horns that would be required to meet the desired spectra, as well as to evaluate possible supplemental gas jet noise sources. The knowledge obtained in each of these test programs enabled the design of the RATF sound generation system to confidently advance to its final acoustic design and subsequent on-going construction.

  18. Estimation bias and bias correction in reduced rank autoregressions

    DEFF Research Database (Denmark)

    Nielsen, Heino Bohn

    2017-01-01

    This paper characterizes the finite-sample bias of the maximum likelihood estimator (MLE) in a reduced rank vector autoregression and suggests two simulation-based bias corrections. One is a simple bootstrap implementation that approximates the bias at the MLE. The other is an iterative root...

  19. Accelerators for Society - TIARA 2012 Test Infrastructure and Accelerator Research Area (in Polish)

    CERN Document Server

    Romaniuk, R S

    2013-01-01

    TIARA (Test Infrastructure and Accelerator Research Area - Preparatory Phae) is an European Collaboration of Accelerator Technology, which by running research projects, technical, networks and infrastructural has a duty to integrate the research and technical communities and infrastructures in the global scale of Europe. The Collaboration gathers all research centers with large accelerator infrastructures. Other ones, like universities, are affiliated as associate members. TIARA-PP (preparatory phase) is an European infrastructural project run by this Consortium and realized inside EU-FP7. The paper presents a general overview of TIARA activities, with an introduction containing a portrait of contemporary accelerator technology and a digest of its applications in modern society.

  20. Research program of the high temperature engineering test reactor for upgrading the HTGR technology

    International Nuclear Information System (INIS)

    Kunitomi, Kazuhiko; Tachibana, Yukio; Takeda, Takeshi; Saikusa, Akio; Sawa, Kazuhiro

    1997-07-01

    The High Temperature Engineering Test Reactor (HTTR) is a graphite-moderated and helium-cooled reactor with an outlet power of 30 MW and outlet coolant temperature of 950degC, and its first criticality will be attained at the end of 1997. In the HTTR, researches establishing and upgrading the technology basis necessary for an HTGR and innovative basic researches for a high temperature engineering will be conducted. A research program of the HTTR for upgrading the technology basis for the HTGR was determined considering realization of future generation commercial HTGRs. This paper describes a research program of the HTTR. (author)

  1. Rational Learning and Information Sampling: On the "Naivety" Assumption in Sampling Explanations of Judgment Biases

    Science.gov (United States)

    Le Mens, Gael; Denrell, Jerker

    2011-01-01

    Recent research has argued that several well-known judgment biases may be due to biases in the available information sample rather than to biased information processing. Most of these sample-based explanations assume that decision makers are "naive": They are not aware of the biases in the available information sample and do not correct for them.…

  2. Weight Bias: A Systematic Review of Characteristics and Psychometric Properties of Self-Report Questionnaires.

    Science.gov (United States)

    Lacroix, Emilie; Alberga, Angela; Russell-Mathew, Shelly; McLaren, Lindsay; von Ranson, Kristin

    2017-01-01

    People living with overweight and obesity often experience weight-based stigmatization. Investigations of the prevalence and correlates of weight bias and evaluation of weight bias reduction interventions depend upon psychometrically-sound measurement. Our paper is the first to comprehensively evaluate the psychometric properties, use of people-first language within items, and suitability for use with various populations of available self-report measures of weight bias. We searched five electronic databases to identify English-language self-report questionnaires of weight bias. We rated each questionnaire's psychometric properties based on initial validation reports and subsequent use, and examined item language. Our systematic review identified 40 original self-report questionnaires. Most questionnaires were brief, demonstrated adequate internal consistency, and tapped key cognitive and affective dimensions of weight bias such as stereotypes and blaming. Current psychometric evidence is incomplete for many questionnaires, particularly with regard to the properties of test-retest reliability, sensitivity to change as well as discriminant and structural validity. Most questionnaires were developed prior to debate surrounding terminology preferences, and do not employ people-first language in the items administered to participants. We provide information and recommendations for clinicians and researchers in selecting psychometrically sound measures of weight bias for various purposes and populations, and discuss future directions to improve measurement of this construct. © 2017 The Author(s) Published by S. Karger GmbH, Freiburg.

  3. Think leader, think White? Capturing and weakening an implicit pro-White leadership bias.

    Science.gov (United States)

    Gündemir, Seval; Homan, Astrid C; de Dreu, Carsten K W; van Vugt, Mark

    2014-01-01

    Across four studies, we found evidence for an implicit pro-White leadership bias that helps explain the underrepresentation of ethnic minorities in leadership positions. Both White-majority and ethnic minority participants reacted significantly faster when ethnically White names and leadership roles (e.g., manager; Study 1) or leadership traits (e.g., decisiveness; Study 2 & 3) were paired in an Implicit Association Test (IAT) rather than when ethnic minority names and leadership traits were paired. Moreover, the implicit pro-White leadership bias showed discriminant validity with the conventional implicit bias measures (Study 3). Importantly, results showed that the pro-White leadership bias can be weakened when situational cues increase the salience of a dual identity (Study 4). This, in turn, can diminish the explicit pro-White bias in promotion related decision making processes (Study 4). This research offers a new tool to measure the implicit psychological processes underlying the underrepresentation of ethnic minorities in leadership positions and proposes interventions to weaken such biases.

  4. Think Leader, Think White? Capturing and Weakening an Implicit Pro-White Leadership Bias

    Science.gov (United States)

    Gündemir, Seval; Homan, Astrid C.; de Dreu, Carsten K. W.; van Vugt, Mark

    2014-01-01

    Across four studies, we found evidence for an implicit pro-White leadership bias that helps explain the underrepresentation of ethnic minorities in leadership positions. Both White-majority and ethnic minority participants reacted significantly faster when ethnically White names and leadership roles (e.g., manager; Study 1) or leadership traits (e.g., decisiveness; Study 2 & 3) were paired in an Implicit Association Test (IAT) rather than when ethnic minority names and leadership traits were paired. Moreover, the implicit pro-White leadership bias showed discriminant validity with the conventional implicit bias measures (Study 3). Importantly, results showed that the pro-White leadership bias can be weakened when situational cues increase the salience of a dual identity (Study 4). This, in turn, can diminish the explicit pro-White bias in promotion related decision making processes (Study 4). This research offers a new tool to measure the implicit psychological processes underlying the underrepresentation of ethnic minorities in leadership positions and proposes interventions to weaken such biases. PMID:24416181

  5. Think leader, think White? Capturing and weakening an implicit pro-White leadership bias.

    Directory of Open Access Journals (Sweden)

    Seval Gündemir

    Full Text Available Across four studies, we found evidence for an implicit pro-White leadership bias that helps explain the underrepresentation of ethnic minorities in leadership positions. Both White-majority and ethnic minority participants reacted significantly faster when ethnically White names and leadership roles (e.g., manager; Study 1 or leadership traits (e.g., decisiveness; Study 2 & 3 were paired in an Implicit Association Test (IAT rather than when ethnic minority names and leadership traits were paired. Moreover, the implicit pro-White leadership bias showed discriminant validity with the conventional implicit bias measures (Study 3. Importantly, results showed that the pro-White leadership bias can be weakened when situational cues increase the salience of a dual identity (Study 4. This, in turn, can diminish the explicit pro-White bias in promotion related decision making processes (Study 4. This research offers a new tool to measure the implicit psychological processes underlying the underrepresentation of ethnic minorities in leadership positions and proposes interventions to weaken such biases.

  6. White Mountain Research Station: 25 years of high-altitude research. [organization and functions of test facility for high altitude research

    Science.gov (United States)

    Pace, N.

    1973-01-01

    The organization and functions of a test facility for conducting research projects at high altitudes are discussed. The projects conducted at the facility include the following: (1) bird physiology, (2) cardiorespiratory physiology, (3) endocrinological studies, (4) neurological studies, (5) metabolic studies, and (6) geological studies.

  7. Study on development of evaluation technique of in-situ tracer test in Horonobe Underground Research Laboratory project (Contract research)

    International Nuclear Information System (INIS)

    Yokota, Hideharu; Amano, Kenji; Maekawa, Keisuke; Kunimaru, Takanori; Naemura, Yumi; Ijiri, Yuji; Motoshima, Takayuki; Suzuki, Shunichi; Teshima, Kazufumi

    2013-06-01

    In the Horonobe Underground Research Laboratory Project, in-situ tracer tests are valuable and important as the investigations to obtain the mass transportation data of fractures in hostrock. However, it is difficult that the in-situ tests are executed under various conditions due to long test period and the tests results are evaluated about permeable heterogeneity in a fracture and/or scale effects. In this study, a number of tracer tests are simulated in a fictitious single plate fracture generated on computer. And the transport parameters are identified by fitting one- and two-dimensional models to the breakthrough curves obtained from the simulations in order to investigate the applicability of these models to the evaluation of in-situ tracer test. As a result, one-dimensional model yields larger longitudinal dispersion length than two-dimensional model in the both cases of homogeneous and heterogeneous hydraulic conductivity fields of the fictitious fracture. This is because that the effect of transverse dispersion has to be included in the longitudinal dispersion length parameter in the one-dimensional model. It is also found that the larger dipole ratio and the larger natural groundwater flow crossing the flow generated between two boreholes make the identified longitudinal dispersion length larger. And, the longitudinal dispersion length identified from a tracer test is smaller and/or larger than the macroscopic longitudinal dispersion length identified from whole fracture. It is clarified that these are occurred by shorter or longer distance between boreholes compare to the correlation length of geostatistical heterogeneity of fictitious fracture. (author)

  8. 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...

  9. Report of test and research results on atomic energy obtained in national institutes in fiscal 1987

    International Nuclear Information System (INIS)

    1989-01-01

    The test and research regarding the utilization of atomic energy carried out in national institutions have produced many valuable results in diverse fields so far, such as nuclear fusion, safety research, food irradiation and medicine, since the budget had been appropriated for the first time in 1956. It has accomplished large role in the promotion of atomic energy utilization in Japan. This report is volume 28, in which the results of the test and research on atomic energy utilization carried out by national institutions in fiscal year 1987 are summarized. It is hoped that the understanding about the recent trend and the results of the test and research on atomic energy utilization is further promoted by this report. The contents of this report are nuclear fusion; the research on engineering safety and environmental radioactivity safety; food irradiation; the countermeasures against cancer; fertilized soil, the improvement of quality, the protection of plants and the improvement of breeding in agriculture and fishery fields; diagnosis and medical treatment, pharmaceuticals, environmental hygiene and the application to physiology and pathology in medical field; radiation measurement and process analysis in mining and industry fields; nuclear reactor materials and nuclear-powered ships; civil engineering; radioactivation analysis; the research on the prevention of injuries; and the basic researches on materials and acessment and reduction of irradiation risk. (J.P.N.)

  10. Operation, test, research and development of the high temperature engineering test reactor (HTTR). FY1999-2001

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-05-01

    The HTTR (High Temperature Engineering Test Reactor) with the thermal power of 30 MW and the reactor outlet coolant temperature of 850/950 degC is the first high temperature gas-cooled reactor (HTGR) in Japan, which uses coated fuel particle, graphite for core components, and helium gas for primary coolant. The HTTR, which locates at the south-west area of 50,000 m{sup 2} in the Oarai Research Establishment, had been constructed since 1991 before accomplishing the first criticality on November 10, 1998. Rise to power tests of the HTTR started in September, 1999 and the rated thermal power of 30 MW and the reactor outlet coolant temperature of 850 degC was attained in December 2001. JAERI received the certificate of pre-operation test, that is, the commissioning license for the HTTR in March 2002. This report summarizes operation, tests, maintenance, radiation control, and construction of components and facilities for the HTTR as well as R and Ds on HTGRs from FY1999 to 2001. (author)

  11. Review of Evidence of Environmental Impacts of Animal Research and Testing

    Directory of Open Access Journals (Sweden)

    Katherine Groff

    2014-06-01

    Full Text Available Millions of animals are used in research and toxicity testing, including in drug, medical device, chemical, cosmetic, personal care, household, and other product sectors, but the environmental consequences are yet to be adequately addressed. Evidence suggests that their use and disposal, and the associated use of chemicals and supplies, contribute to pollution as well as adverse impacts on biodiversity and public health. The objective of this review is to examine such evidence. The review includes examinations of (1 resources used in animal research; (2 waste production in laboratories; (3 sources of pollution; (4 impacts on laboratory workers’ health; and (5 biodiversity impacts. The clear conclusion from the review is that the environmental implications of animal testing must be acknowledged, reported, and taken into account as another factor in addition to ethical and scientific reasons weighing heavily in favor of moving away from allowing and requiring animal use in research and testing.

  12. Effects of standard and explicit cognitive bias modification and computer-administered cognitive-behaviour therapy on cognitive biases and social anxiety.

    Science.gov (United States)

    Mobini, Sirous; Mackintosh, Bundy; Illingworth, Jo; Gega, Lina; Langdon, Peter; Hoppitt, Laura

    2014-06-01

    This study examines the effects of a single session of Cognitive Bias Modification to induce positive Interpretative bias (CBM-I) using standard or explicit instructions and an analogue of computer-administered CBT (c-CBT) program on modifying cognitive biases and social anxiety. A sample of 76 volunteers with social anxiety attended a research site. At both pre- and post-test, participants completed two computer-administered tests of interpretative and attentional biases and a self-report measure of social anxiety. Participants in the training conditions completed a single session of either standard or explicit CBM-I positive training and a c-CBT program. Participants in the Control (no training) condition completed a CBM-I neutral task matched the active CBM-I intervention in format and duration but did not encourage positive disambiguation of socially ambiguous or threatening scenarios. Participants in both CBM-I programs (either standard or explicit instructions) and the c-CBT condition exhibited more positive interpretations of ambiguous social scenarios at post-test and one-week follow-up as compared to the Control condition. Moreover, the results showed that CBM-I and c-CBT, to some extent, changed negative attention biases in a positive direction. Furthermore, the results showed that both CBM-I training conditions and c-CBT reduced social anxiety symptoms at one-week follow-up. This study used a single session of CBM-I training, however multi-sessions intervention might result in more endurable positive CBM-I changes. A computerised single session of CBM-I and an analogue of c-CBT program reduced negative interpretative biases and social anxiety. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Positioning of Weight Bias: Moving towards Social Justice.

    Science.gov (United States)

    Nutter, Sarah; Russell-Mayhew, Shelly; Alberga, Angela S; Arthur, Nancy; Kassan, Anusha; Lund, Darren E; Sesma-Vazquez, Monica; Williams, Emily

    2016-01-01

    Weight bias is a form of stigma with detrimental effects on the health and wellness of individuals with large bodies. Researchers from various disciplines have recognized weight bias as an important topic for public health and for professional practice. To date, researchers from various areas have approached weight bias from independent perspectives and from differing theoretical orientations. In this paper, we examined the similarities and differences between three perspectives (i.e., weight-centric, non-weight-centric (health-centric), and health at every size) used to understand weight bias and approach weight bias research with regard to (a) language about people with large bodies, (b) theoretical position, (c) identified consequences of weight bias, and (d) identified influences on weight-based social inequity. We suggest that, despite differences, each perspective acknowledges the negative influences that position weight as being within individual control and the negative consequences of weight bias. We call for recognition and discussion of weight bias as a social justice issue in order to change the discourse and professional practices extended towards individuals with large bodies. We advocate for an emphasis on social justice as a uniting framework for interdisciplinary research on weight bias.

  14. Problems studied within the state research project New Methods of Nondestructive Materials Testing Using Ionizing Radiation

    International Nuclear Information System (INIS)

    Mysak, F.; Strba, J.

    1979-01-01

    A state research project is described divided into ten subprojects, viz.: New trends of ionizing radiation detection using television technology in nondestructive testing; the application of accelerators for thick-walled product testing; the atlas of butt welds of medium thicknesses; the application of radioanalytical methods in testing the wear of gearboxes and other components of instrument parts; multielemental analyses of combustion engine wear using radionuclides; the application of radioisotope methods in research into wear of antifriction bearings of trucks and railway cars; the application of radionuclides in assessing corrosion resistance of steels and corrosion protection systems; the application of radionuclide methods in improving the quality of high-grade steel production; the selection and testing of radionuclide instruments for building production control, intermediate and acceptance checks; and radioisotope methods for building machine and equipment control. (M.S.)

  15. Gender Bias Affects Forests Worldwide

    Directory of Open Access Journals (Sweden)

    Marlène Elias

    2017-04-01

    Full Text Available Gender biases persist in forestry research and practice. These biases result in reduced scientific rigor and inequitable, ineffective, and less efficient policies, programs, and interventions. Drawing from a two-volume collection of current and classic analyses on gender in forests, we outline five persistent and inter-related themes: gendered governance, tree tenure, forest spaces, division of labor, and ecological knowledge. Each emerges across geographic regions in the northern and southern hemisphere and reflects inequities in women’s and men’s ability to make decisions about and benefit from trees, forests, and their products. Women’s ability to participate in community-based forest governance is typically less than men’s, causing concern for social equity and forest stewardship. Women’s access to trees and their products is commonly more limited than men’s, and mediated by their relationship with their male counterparts. Spatial patterns of forest use reflect gender norms and taboos, and men’s greater access to transportation. The division of labor results in gender specialization in the collection of forest products, with variations in gender roles across regions. All these gender differences result in ecological knowledge that is distinct but also complementary and shifting across the genders. The ways gender plays out in relation to each theme may vary across cultures and contexts, but the influence of gender, which intersects with other factors of social differentiation in shaping forest landscapes, is global.

  16. Subcritical Measurements Research Program for Fresh and Spent Materials Test Reactor Fuels

    International Nuclear Information System (INIS)

    Blanchard, A.

    1999-01-01

    'A series of subcritical noise measurements were performed on fresh and spent University of Missouri Research Reactor fuel assemblies. These experimental measurements were performed for the purposes of providing benchmark quality data for validating transport theory computer codes and nuclear cross-section data used to perform criticality safety analyses for highly enriched, uranium-aluminum Material Test Reactor fuel assemblies. A mechanical test rig was designed and built to hold up to four fuel assemblies and neutron detectors in a subcritical array. The rig provided researchers with the ability to evaluate the reactivity effects of variable fuel/detector spacing, fuel rotation, and insertion of metal reflector plates into the lattice.'

  17. The JRC Nanomaterials Repository: A unique facility providing representative test materials for nanoEHS research.

    Science.gov (United States)

    Totaro, Sara; Cotogno, Giulio; Rasmussen, Kirsten; Pianella, Francesca; Roncaglia, Marco; Olsson, Heidi; Riego Sintes, Juan M; Crutzen, Hugues P

    2016-11-01

    The European Commission has established a Nanomaterials Repository that hosts industrially manufactured nanomaterials that are distributed world-wide for safety testing of nanomaterials. In a first instance these materials were tested in the OECD Testing Programme. They have then also been tested in several EU funded research projects. The JRC Repository of Nanomaterials has thus developed into serving the global scientific community active in the nanoEHS (regulatory) research. The unique Repository facility is a state-of-the-art installation that allows customised sub-sampling under the safest possible conditions, with traceable final sample vials distributed world-wide for research purposes. This paper describes the design of the Repository to perform a semi-automated subsampling procedure, offering high degree of flexibility and precision in the preparation of NM vials for customers, while guaranteeing the safety of the operators, and environmental protection. The JRC nanomaterials are representative for part of the world NMs market. Their wide use world-wide facilitates the generation of comparable and reliable experimental results and datasets in (regulatory) research by the scientific community, ultimately supporting the further development of the OECD regulatory test guidelines. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  18. A Preliminary Analysis of Reactor Performance Test (LOEP) for a Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyeonil; Park, Su-Ki [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    The final phase of commissioning is reactor performance test, which is to prove the integrated performance and safety of the research reactor at full power with fuel loaded such as neutron power calibration, Control Absorber Rod/Second Shutdown Rod drop time, InC function test, Criticality, Rod worth, Core heat removal with natural mechanism, and so forth. The last test will be safety-related one to assure the result of the safety analysis of the research reactor is marginal enough to be sure about the nuclear safety by showing the reactor satisfies the acceptance criteria of the safety functions such as for reactivity control, maintenance of auxiliaries, reactor pool water inventory control, core heat removal, and confinement isolation. After all, the fuel integrity will be ensured by verifying there is no meaningful change in the radiation levels. To confirm the performance of safety equipment, loss of normal electric power (LOEP), possibly categorized as Anticipated Operational Occurrence (AOO), is selected as a key experiment to figure out how safe the research reactor is before turning over the research reactor to the owner. This paper presents a preliminary analysis of the reactor performance test (LOEP) for a research reactor. The results showed how different the transient between conservative estimate and best estimate will look. Preliminary analyses have shown all probable thermal-hydraulic transient behavior of importance as to opening of flap valve, minimum critical heat flux ratio, the change of flow direction, and important values of thermal-hydraulic parameters.

  19. Research of the possibility of using neural networks in the tests of locomotive hydraulic transmissions

    OpenAIRE

    КЛЮШНИК, І. А.

    2017-01-01

    The possibility of developing a self-diagnostics system of the diesel locomotives hydraulic transmissions information-measuring test system is researched. The use of neural networks and fuzzy logic for the development of a self-diagnostics system of the diesel locomotives hydraulic transmissions information-measuring tests system is proposed. As the initial stage of developing a diagnostic system using neural networks, a neural network is presented which predicts the rotational speed of the h...

  20. Biasing vector network analyzers using variable frequency and amplitude signals

    Science.gov (United States)

    Nobles, J. E.; Zagorodnii, V.; Hutchison, A.; Celinski, Z.

    2016-08-01

    We report the development of a test setup designed to provide a variable frequency biasing signal to a vector network analyzer (VNA). The test setup is currently used for the testing of liquid crystal (LC) based devices in the microwave region. The use of an AC bias for LC based devices minimizes the negative effects associated with ionic impurities in the media encountered with DC biasing. The test setup utilizes bias tees on the VNA test station to inject the bias signal. The square wave biasing signal is variable from 0.5 to 36.0 V peak-to-peak (VPP) with a frequency range of DC to 10 kHz. The test setup protects the VNA from transient processes, voltage spikes, and high-frequency leakage. Additionally, the signals to the VNA are fused to ½ amp and clipped to a maximum of 36 VPP based on bias tee limitations. This setup allows us to measure S-parameters as a function of both the voltage and the frequency of the applied bias signal.