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Sample records for publication bias conclusion

  1. Publication bias in epidemiological studies.

    Science.gov (United States)

    Siddiqi, Nazish

    2011-06-01

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

  2. Editorial bias in scientific publications.

    Science.gov (United States)

    Matías-Guiu, J; García-Ramos, R

    2011-01-01

    Many authors believe that there are biases in scientific publications. Editorial biases include publication bias; which refers to those situations where the results influence the editor's decision, and editorial bias refers to those situations where factors related with authors or their environment influence the decision. This paper includes an analysis of the situation of editorial biases. One bias is where mainly articles with positive results are accepted, as opposed to those with negative results. Another is latent bias, where positive results are published before those with negative results. In order to examine editorial bias, this paper analyses the influence of where the article originated; the country or continent, academic centre of origin, belonging to cooperative groups, and the maternal language of the authors. The article analyses biases in the editorial process in the publication of funded clinical trials. Editorial biases exists. Authors, when submitting their manuscript, should analyse different journals and decide where their article will receive adequate treatment. Copyright © 2010 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

  3. Adolescents with Autism Spectrum Disorder Show a Circumspect Reasoning Bias Rather than "Jumping-to-Conclusions"

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    Brosnan, Mark; Chapman, Emma; Ashwin, Chris

    2014-01-01

    People with autism spectrum disorders (ASD) often take longer to make decisions. The Autism-Psychosis Model proposes that people with autism and psychosis show the opposite pattern of results on cognitive tasks. As those with psychosis show a jump-to-conclusions reasoning bias, those with ASD should show a circumspect reasoning bias.…

  4. Systematic review of the empirical evidence of study publication bias and outcome reporting bias.

    Directory of Open Access Journals (Sweden)

    Kerry Dwan

    Full Text Available BACKGROUND: The increased use of meta-analysis in systematic reviews of healthcare interventions has highlighted several types of bias that can arise during the completion of a randomised controlled trial. Study publication bias has been recognised as a potential threat to the validity of meta-analysis and can make the readily available evidence unreliable for decision making. Until recently, outcome reporting bias has received less attention. METHODOLOGY/PRINCIPAL FINDINGS: We review and summarise the evidence from a series of cohort studies that have assessed study publication bias and outcome reporting bias in randomised controlled trials. Sixteen studies were eligible of which only two followed the cohort all the way through from protocol approval to information regarding publication of outcomes. Eleven of the studies investigated study publication bias and five investigated outcome reporting bias. Three studies have found that statistically significant outcomes had a higher odds of being fully reported compared to non-significant outcomes (range of odds ratios: 2.2 to 4.7. In comparing trial publications to protocols, we found that 40-62% of studies had at least one primary outcome that was changed, introduced, or omitted. We decided not to undertake meta-analysis due to the differences between studies. CONCLUSIONS: Recent work provides direct empirical evidence for the existence of study publication bias and outcome reporting bias. There is strong evidence of an association between significant results and publication; studies that report positive or significant results are more likely to be published and outcomes that are statistically significant have higher odds of being fully reported. Publications have been found to be inconsistent with their protocols. Researchers need to be aware of the problems of both types of bias and efforts should be concentrated on improving the reporting of trials.

  5. Is there evidence of publication biases in JDM research?

    Directory of Open Access Journals (Sweden)

    Frank Renkewitz

    2011-12-01

    Full Text Available It is a long known problem that the preferential publication of statistically significant results (publication bias may lead to incorrect estimates of the true effects being investigated. Even though other research areas (e.g., medicine, biology are aware of the problem, and have identified strong publication biases, researchers in judgment and decision making (JDM largely ignore it. We reanalyzed two current meta-analyses in this area. Both showed evidence of publication biases that may have led to a substantial overestimation of the true effects they investigated. A review of additional JDM meta-analyses shows that most meta-analyses conducted no or insufficient analyses of publication bias. However, given our results and the rareness of non-significant effects in the literature, we suspect that biases occur quite often. These findings suggest that (a conclusions based on meta-analyses without reported tests of publication bias should be interpreted with caution and (b publication policies and standard research practices should be revised to overcome the problem.

  6. A fine-grained analysis of the jumping-to-conclusions bias in schizophrenia

    Directory of Open Access Journals (Sweden)

    Steffen Moritz

    2009-12-01

    Full Text Available Impaired decision behavior has been repeatedly observed in schizophrenia patients. We investigated several cognitive mechanisms that might contribute to the jumping-to-conclusions bias (JTC seen in schizophrenia patients: biases in information-gathering, information weighting and integration, and overconfidence, using the process tracing paradigm Mouselab. Mouselab allows for an in-depth exploration of various decision-making processes in a structured information environment. A total of 37 schizophrenia patients and 30 healthy controls participated in the experiment. Although showing less focused and systematic information search, schizophrenia patients practically considered all pieces of information and showed no JTC in the sense of collecting less pieces of evidence. Choices of patients and controls both approximated a rational solution quite well, but patients showed more extreme confidence ratings. Both groups mainly used weighted additive decision strategies for information integration and only a small proportion relied on simple heuristics. Under high stress induced by affective valence plus time pressure, however, schizophrenia patients switched to equal weighting strategies: less valid cues and more valid ones were weighted equally.

  7. An investigation of the "jumping to conclusions" data-gathering bias and paranoid thoughts in Asperger syndrome.

    Science.gov (United States)

    Jänsch, Claire; Hare, Dougal Julian

    2014-01-01

    The existence of a data-gathering bias, in the form of jumping to conclusions, and links to paranoid ideation was investigated in Asperger syndrome (AS). People with AS (N = 30) were compared to a neurotypical control group (N = 30) on the Reading the Mind in the Eyes and the Beads tasks, with self-report measures of depression, general anxiety, social anxiety, self-consciousness and paranoid ideation. The AS group performed less well than the control group on the Reading the Mind in the Eyes Task with regard to accuracy but responded more quickly and tended to make decisions on the basis of less evidence on the Beads Task with 50 % demonstrating a clear 'jumping to conclusions bias', whereas none of the control group showed such a bias. Depression and general anxiety were associated with paranoid ideation but not data-gathering style, which was contrary to expectation.

  8. Evaluation of the 'Jumping to conclusions' bias in different subgroups of the at-risk mental state

    DEFF Research Database (Denmark)

    Rausch, F; Eisenacher, S; Elkin, H

    2016-01-01

    BACKGROUND: Patients with psychosis display the so-called 'Jumping to Conclusions' bias (JTC) - a tendency for hasty decision-making in probabilistic reasoning tasks. So far, only a few studies have evaluated the JTC bias in 'at-risk mental state' (ARMS) patients, specifically in ARMS samples...... symptoms (BS). Similar data were available for 30 healthy control participants matched for age, gender, education and premorbid verbal intelligence. ARMS patients were identified by the Structured Interview for Prodromal Symptoms (SIPS) and the Schizophrenia Proneness Instrument - Adult Version (SPI...

  9. An Investigation of the "Jumping to Conclusions" Data-Gathering Bias and Paranoid Thoughts in Asperger Syndrome

    Science.gov (United States)

    Jänsch, Claire; Hare, Dougal Julian

    2014-01-01

    The existence of a data-gathering bias, in the form of jumping to conclusions, and links to paranoid ideation was investigated in Asperger syndrome (AS). People with AS (N = 30) were compared to a neurotypical control group (N = 30) on the Reading the Mind in the Eyes and the Beads tasks, with self-report measures of depression, general anxiety,…

  10. Neurocognitive deficits are relevant for the jumping-to-conclusions bias, but not for delusions: A longitudinal study

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    Christina Andreou

    2015-03-01

    Full Text Available Patients with delusions exhibit an increased tendency to arrive at decisions based on very limited evidence (jumping-to-conclusions; JTC, making this reasoning bias relevant for the treatment of delusions. Neurocognitive deficits contribute to JTC, but it is not known whether this has any bearing on the clinical syndrome of delusions. We addressed this question by reanalyzing data from an efficacy study of non-pharmacological interventions as adjunctive treatments in schizophrenia. We investigated the longitudinal associations of cognitive functioning, JTC and delusions in patients with psychotic disorders receiving either a metacognitive intervention addressing reasoning biases (n = 59, or cognitive remediation (n = 58. Both interventions improved JTC; in the cognitive remediation group, tentative evidence suggested that better neurocognitive performance contributed to this improvement. However, JTC gains were associated with delusion improvement only in the metacognitive intervention group, suggesting a content-specific mechanism of action.

  11. Publication Bias The "File-Drawer Problem" in Scientific Inference

    CERN Document Server

    Scargle, J D

    1999-01-01

    Publication bias arises whenever the probability that a study is published depends on the statistical significance of its results. This bias, often called the file-drawer effect since the unpublished results are imagined to be tucked away in researchers' file cabinets, is potentially a severe impediment to combining the statistical results of studies collected from the literature. With almost any reasonable quantitative model for publication bias, only a small number of studies lost in the file-drawer will produce a significant bias. This result contradicts the well known Fail Safe File Drawer (FSFD) method for setting limits on the potential harm of publication bias, widely used in social, medical and psychic research. This method incorrectly treats the file drawer as unbiased, and almost always misestimates the seriousness of publication bias. A large body of not only psychic research, but medical and social science studies, has mistakenly relied on this method to validate claimed discoveries. Statistical c...

  12. Publication bias in dermatology systematic reviews and meta-analyses.

    Science.gov (United States)

    Atakpo, Paul; Vassar, Matt

    2016-05-01

    Systematic reviews and meta-analyses in dermatology provide high-level evidence for clinicians and policy makers that influence clinical decision making and treatment guidelines. One methodological problem with systematic reviews is the under representation of unpublished studies. This problem is due in part to publication bias. Omission of statistically non-significant data from meta-analyses may result in overestimation of treatment effect sizes which may lead to clinical consequences. Our goal was to assess whether systematic reviewers in dermatology evaluate and report publication bias. Further, we wanted to conduct our own evaluation of publication bias on meta-analyses that failed to do so. Our study considered systematic reviews and meta-analyses from ten dermatology journals from 2006 to 2016. A PubMed search was conducted, and all full-text articles that met our inclusion criteria were retrieved and coded by the primary author. 293 articles were included in our analysis. Additionally, we formally evaluated publication bias in meta-analyses that failed to do so using trim and fill and cumulative meta-analysis by precision methods. Publication bias was mentioned in 107 articles (36.5%) and was formally evaluated in 64 articles (21.8%). Visual inspection of a funnel plot was the most common method of evaluating publication bias. Publication bias was present in 45 articles (15.3%), not present in 57 articles (19.5%) and not determined in 191 articles (65.2%). Using the trim and fill method, 7 meta-analyses (33.33%) showed evidence of publication bias. Although the trim and fill method only found evidence of publication bias in 7 meta-analyses, the cumulative meta-analysis by precision method found evidence of publication bias in 15 meta-analyses (71.4%). Many of the reviews in our study did not mention or evaluate publication bias. Further, of the 42 articles that stated following PRISMA reporting guidelines, 19 (45.2%) evaluated for publication bias. In

  13. Publication bias and the failure of replication in experimental psychology.

    Science.gov (United States)

    Francis, Gregory

    2012-12-01

    Replication of empirical findings plays a fundamental role in science. Among experimental psychologists, successful replication enhances belief in a finding, while a failure to replicate is often interpreted to mean that one of the experiments is flawed. This view is wrong. Because experimental psychology uses statistics, empirical findings should appear with predictable probabilities. In a misguided effort to demonstrate successful replication of empirical findings and avoid failures to replicate, experimental psychologists sometimes report too many positive results. Rather than strengthen confidence in an effect, too much successful replication actually indicates publication bias, which invalidates entire sets of experimental findings. Researchers cannot judge the validity of a set of biased experiments because the experiment set may consist entirely of type I errors. This article shows how an investigation of the effect sizes from reported experiments can test for publication bias by looking for too much successful replication. Simulated experiments demonstrate that the publication bias test is able to discriminate biased experiment sets from unbiased experiment sets, but it is conservative about reporting bias. The test is then applied to several studies of prominent phenomena that highlight how publication bias contaminates some findings in experimental psychology. Additional simulated experiments demonstrate that using Bayesian methods of data analysis can reduce (and in some cases, eliminate) the occurrence of publication bias. Such methods should be part of a systematic process to remove publication bias from experimental psychology and reinstate the important role of replication as a final arbiter of scientific findings.

  14. 'Jumping to conclusions' data-gathering bias in psychosis and other psychiatric disorders - Two meta-analyses of comparisons between patients and healthy individuals.

    Science.gov (United States)

    So, Suzanne Ho-Wai; Siu, Nicolson Yat-Fan; Wong, Hau-Lam; Chan, Wai; Garety, Philippa Anne

    2016-06-01

    There has been an increase in attention to studying shared mechanisms underlying psychiatric disorders. The 'Jumping to conclusions' (JTC(1)) bias, a tendency to make decisions with certainty based on insufficient information, has been reported in patients with psychosis, and process-based treatment protocols targeting this bias have recently been developed. This review aimed to investigate to what extent the JTC bias, measured by various tasks, is associated with psychotic disorders and other psychiatric disorders using a meta-analytic approach. We examined 6864 articles published between 1990 and 2015, and meta-analysed 46 studies. The first meta-analysis included 40 effect sizes comparing patients with schizophrenia spectrum or other psychotic disorders and healthy controls. There was a hastier data-gathering style in patients with psychosis than healthy individuals, with a moderate aggregated effect size. The second meta-analysis included 18 effect sizes comparing patients with non-psychotic disorders and healthy controls. There was marked heterogeneity in effect sizes and evidence for publication bias. After removal of outliers, the aggregated effect size for JTC was not statistically significant. A planned subgroup analysis showed no significant effect of JTC in depression. Other diagnostic subgroups yielded small non-significant results. Therefore, our findings do not support the suggestion that JTC is a transdiagnostic phenomenon beyond psychosis.

  15. A Bayesian approach to mitigation of publication bias.

    Science.gov (United States)

    Guan, Maime; Vandekerckhove, Joachim

    2016-02-01

    The reliability of published research findings in psychology has been a topic of rising concern. Publication bias, or treating positive findings differently from negative findings, is a contributing factor to this "crisis of confidence," in that it likely inflates the number of false-positive effects in the literature. We demonstrate a Bayesian model averaging approach that takes into account the possibility of publication bias and allows for a better estimate of true underlying effect size. Accounting for the possibility of bias leads to a more conservative interpretation of published studies as well as meta-analyses. We provide mathematical details of the method and examples.

  16. Highlights and conclusions from the Eastern Mediterranean Public Health Network (EMPHNET) conference 2011.

    Science.gov (United States)

    Al Nsour, M; Kaiser, R; Abd Elkreem, E; Walke, H; Kandeel, A; Bloland, R

    2012-02-01

    As a follow up of a short communication that the Eastern Mediterranean Health journal published in December 2011, this article reports on highlights and conclusions from scientific abstracts, methodology workshops and plenary sessions that were presented as part of the Eastern Mediterranean Public Health Network (EMPHNET) conference held from 6 to 9 December 2011 in Sharm Al Sheikh, Egypt.

  17. Inadequate use and regulation of interventions against publication bias decreases their effectiveness: a systematic review

    Science.gov (United States)

    Thaler, Kylie; Kien, Christina; Nussbaumer, Barbara; Van Noord, Megan G.; Griebler, Ursula; Klerings, Irma; Gartlehner, Gerald

    2015-01-01

    Objectives To determine the effectiveness of interventions designed to prevent or reduce publication and related biases. Study Design and Setting We searched multiple databases and performed manual searches using terms related to publication bias and known interventions against publication bias. We dually reviewed citations and assessed risk of bias. We synthesized results by intervention and outcomes measured and graded the quality of the evidence (QoE). Results We located 38 eligible studies. The use of prospective trial registries (PTR) has increased since 2005 (seven studies, moderate QoE); however, positive outcome-reporting bias is prevalent (14 studies, low QoE), and information in nonmandatory fields is vague (10 studies, low QoE). Disclosure of financial conflict of interest (CoI) is inadequate (five studies, low QoE). Blinding peer reviewers may reduce geographical bias (two studies, very low QoE), and open-access publishing does not discriminate against authors from low-income countries (two studies, very low QoE). Conclusion The use of PTR and CoI disclosures is increasing; however, the adequacy of their use requires improvement. The effect of open-access publication and blinding of peer reviewers on publication bias is unclear, as is the effect of other interventions such as electronic publication and authors' rights to publish their results. PMID:25835490

  18. Publication Bias ( The "File-Drawer Problem") in Scientific Inference

    Science.gov (United States)

    Scargle, Jeffrey D.; DeVincenzi, Donald (Technical Monitor)

    1999-01-01

    Publication bias arises whenever the probability that a study is published depends on the statistical significance of its results. This bias, often called the file-drawer effect since the unpublished results are imagined to be tucked away in researchers' file cabinets, is potentially a severe impediment to combining the statistical results of studies collected from the literature. With almost any reasonable quantitative model for publication bias, only a small number of studies lost in the file-drawer will produce a significant bias. This result contradicts the well known Fail Safe File Drawer (FSFD) method for setting limits on the potential harm of publication bias, widely used in social, medical and psychic research. This method incorrectly treats the file drawer as unbiased, and almost always miss-estimates the seriousness of publication bias. A large body of not only psychic research, but medical and social science studies, has mistakenly relied on this method to validate claimed discoveries. Statistical combination can be trusted only if it is known with certainty that all studies that have been carried out are included. Such certainty is virtually impossible to achieve in literature surveys.

  19. Publication Bias ( The "File-Drawer Problem") in Scientific Inference

    Science.gov (United States)

    Scargle, Jeffrey D.; DeVincenzi, Donald (Technical Monitor)

    1999-01-01

    Publication bias arises whenever the probability that a study is published depends on the statistical significance of its results. This bias, often called the file-drawer effect since the unpublished results are imagined to be tucked away in researchers' file cabinets, is potentially a severe impediment to combining the statistical results of studies collected from the literature. With almost any reasonable quantitative model for publication bias, only a small number of studies lost in the file-drawer will produce a significant bias. This result contradicts the well known Fail Safe File Drawer (FSFD) method for setting limits on the potential harm of publication bias, widely used in social, medical and psychic research. This method incorrectly treats the file drawer as unbiased, and almost always miss-estimates the seriousness of publication bias. A large body of not only psychic research, but medical and social science studies, has mistakenly relied on this method to validate claimed discoveries. Statistical combination can be trusted only if it is known with certainty that all studies that have been carried out are included. Such certainty is virtually impossible to achieve in literature surveys.

  20. Capture-recapture method for assessing publication bias

    Directory of Open Access Journals (Sweden)

    Jalal Poorolajal

    2010-01-01

    not statistically significant and trill and fill approach made no change in pooled effect.

    Conclusions: Capture recapture method may be a useful practical approach for estimating the number of missing studies which are not usually detected by search strategy, although assumptions of this method may limit its general application in systematic reviews. In addition, capture recapture method may be considered as an alternative approach for estimating the extent of publication bias based on overlapping information rather than mirror image of extreme values on funnel plot.

  1. Detecting and correcting for publication bias in meta-analysis - A truncated normal distribution approach.

    Science.gov (United States)

    Zhu, Qiaohao; Carriere, K C

    2016-01-01

    Publication bias can significantly limit the validity of meta-analysis when trying to draw conclusion about a research question from independent studies. Most research on detection and correction for publication bias in meta-analysis focus mainly on funnel plot-based methodologies or selection models. In this paper, we formulate publication bias as a truncated distribution problem, and propose new parametric solutions. We develop methodologies of estimating the underlying overall effect size and the severity of publication bias. We distinguish the two major situations, in which publication bias may be induced by: (1) small effect size or (2) large p-value. We consider both fixed and random effects models, and derive estimators for the overall mean and the truncation proportion. These estimators will be obtained using maximum likelihood estimation and method of moments under fixed- and random-effects models, respectively. We carried out extensive simulation studies to evaluate the performance of our methodology, and to compare with the non-parametric Trim and Fill method based on funnel plot. We find that our methods based on truncated normal distribution perform consistently well, both in detecting and correcting publication bias under various situations.

  2. Publication bias in clinical trials of electronic health records.

    Science.gov (United States)

    Vawdrey, David K; Hripcsak, George

    2013-02-01

    To measure the rate of non-publication and assess possible publication bias in clinical trials of electronic health records. We searched ClinicalTrials.gov to identify registered clinical trials of electronic health records and searched the biomedical literature and contacted trial investigators to determine whether the results of the trials were published. Publications were judged as positive, negative, or neutral according to the primary outcome. Seventy-six percent of trials had publications describing trial results; of these, 74% were positive, 21% were neutral, and 4% were negative (harmful). Of unpublished studies for which the investigator responded, 43% were positive, 57% were neutral, and none were negative; the lower rate of positive results was significant (pelectronic health record studies is similar to that in other biomedical studies. There appears to be a bias toward publication of positive trials in this domain. Copyright © 2012 Elsevier Inc. All rights reserved.

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

    NARCIS (Netherlands)

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

    2012-01-01

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

  4. Will publication bias vanish in the age of online journals?

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    Berlin, J A

    1992-07-08

    A major advantage of online journals, in contrast to printed journals, is that lack of space is not an obstacle. One obvious benefit of this is the ability to include material that might help clarify or emphasize important points, but that might not be considered essential in the context of the limited space available in a printed journal. A more important benefit of removing space constraints is the potential to eliminate publication bias. This bias occurs when a study is not published because it fails to find any statistically significant differences or associations. While authors play a major role in generating this bias, their belief that publication depends on statistical significance has some foundation in the existing printed literature. Nevertheless, realizing the potential to eliminate publication bias depends largely on the willingness of authors to submit their work. The Online Journal of Current Clinical Trials will judge papers on the quality of the work and the importance of the findings, not on the level of statistical significance achieved in any comparisons made. Valuable papers need no longer be turned away simply because of lack of space.

  5. Recommendations for a uniform assessment of publication bias related to funding source.

    Science.gov (United States)

    van Lent, Marlies; Overbeke, John; Out, Henk J

    2013-09-30

    Numerous studies on publication bias in clinical drug research have been undertaken, particularly on the association between sponsorship and favourable outcomes. However, no standardized methodology for the classification of outcomes and sponsorship has been described. Dissimilarities and ambiguities in this assessment impede the ability to compare and summarize results of studies on publication bias. To guide authors undertaking such studies, this paper provides recommendations for a uniform assessment of publication bias related to funding source. As part of ongoing research into publication bias, 472 manuscripts on randomised controlled trials (RCTs) with drugs, submitted to eight medical journals from January 2010 through April 2012, were reviewed. Information on trial results and sponsorship was extracted from manuscripts. During the start of this evaluation, several problems related to the classification of outcomes, inclusion of post-hoc analyses and follow-up studies of RCTs in the study sample, and assessment of the role of the funding source were encountered. A comprehensive list of recommendations addressing these problems was composed. To assess internal validity, reliability and usability of these recommendations were tested through evaluation of manuscripts submitted to journals included in our study. The proposed recommendations represent a first step towards a uniform method of classifying trial outcomes and sponsorship. This is essential to draw valid conclusions on the role of the funding source in publication bias and will ensure consistency across future studies.

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

    Directory of Open Access Journals (Sweden)

    Gerben ter Riet

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

  7. Cognitive advantage in bilingualism: an example of publication bias?

    Science.gov (United States)

    de Bruin, Angela; Treccani, Barbara; Della Sala, Sergio

    2015-01-01

    It is a widely held belief that bilinguals have an advantage over monolinguals in executive-control tasks, but is this what all studies actually demonstrate? The idea of a bilingual advantage may result from a publication bias favoring studies with positive results over studies with null or negative effects. To test this hypothesis, we looked at conference abstracts from 1999 to 2012 on the topic of bilingualism and executive control. We then determined which of the studies they reported were subsequently published. Studies with results fully supporting the bilingual-advantage theory were most likely to be published, followed by studies with mixed results. Studies challenging the bilingual advantage were published the least. This discrepancy was not due to differences in sample size, tests used, or statistical power. A test for funnel-plot asymmetry provided further evidence for the existence of a publication bias.

  8. Publication bias and the canonization of false facts

    CERN Document Server

    Nissen, Silas B; Gross, Kevin; Bergstrom, Carl T

    2016-01-01

    In the process of scientific inquiry, certain claims accumulate enough support to be established as facts. Unfortunately, not every claim accorded the status of fact turns out to be true. In this paper, we model the dynamic process by which claims are canonized as fact through repeated experimental confirmation. The community's confidence in a claim constitutes a Markov process: each successive published result shifts the degree of belief, until sufficient evidence accumulates to accept the claim as fact or to reject it as false. In our model, publication bias --- in which positive results are published preferentially over negative ones --- influences the distribution of published results. We find that when readers do not know the degree of publication bias and thus cannot condition on it, false claims often can be canonized as facts. Unless a sufficient fraction of negative results are published, the scientific process will do a poor job at discriminating false from true claims. This problem is exacerbated w...

  9. Measuring the effects of publication bias in political science

    Directory of Open Access Journals (Sweden)

    Justin Esarey

    2016-09-01

    Full Text Available Prior research finds that statistically significant results are overrepresented in scientific publications. If significant results are consistently favored in the review process, published results could systematically overstate the magnitude of their findings even under ideal conditions. In this paper, we measure the impact of this publication bias on political science using a new data set of published quantitative results. Although any measurement of publication bias depends on the prior distribution of empirical relationships, we determine that published estimates in political science are on average substantially larger than their true value under a variety of reasonable choices for this prior. We also find that many published estimates have a false positive probability substantially greater than the conventional α = 0.05 threshold for statistical significance if the prior probability of a null relationship exceeds 50%. Finally, although the proportion of published false positives would be reduced if significance tests used a smaller α, this change would not solve the problem of upward bias in the magnitude of published results.

  10. Publication bias in reports of animal stroke studies leads to major overstatement of efficacy.

    Directory of Open Access Journals (Sweden)

    Emily S Sena

    2010-03-01

    Full Text Available The consolidation of scientific knowledge proceeds through the interpretation and then distillation of data presented in research reports, first in review articles and then in textbooks and undergraduate courses, until truths become accepted as such both amongst "experts" and in the public understanding. Where data are collected but remain unpublished, they cannot contribute to this distillation of knowledge. If these unpublished data differ substantially from published work, conclusions may not reflect adequately the underlying biological effects being described. The existence and any impact of such "publication bias" in the laboratory sciences have not been described. Using the CAMARADES (Collaborative Approach to Meta-analysis and Review of Animal Data in Experimental Studies database we identified 16 systematic reviews of interventions tested in animal studies of acute ischaemic stroke involving 525 unique publications. Only ten publications (2% reported no significant effects on infarct volume and only six (1.2% did not report at least one significant finding. Egger regression and trim-and-fill analysis suggested that publication bias was highly prevalent (present in the literature for 16 and ten interventions, respectively in animal studies modelling stroke. Trim-and-fill analysis suggested that publication bias might account for around one-third of the efficacy reported in systematic reviews, with reported efficacy falling from 31.3% to 23.8% after adjustment for publication bias. We estimate that a further 214 experiments (in addition to the 1,359 identified through rigorous systematic review; non publication rate 14% have been conducted but not reported. It is probable that publication bias has an important impact in other animal disease models, and more broadly in the life sciences.

  11. Conclusion: How to operate strategic narratives. Interweaving war, politics, and the public

    DEFF Research Database (Denmark)

    Jakobsen, Peter Viggo; Ringsmose, Jens

    2015-01-01

    conditions for success from these literatures that governments must be able to meet in order to mobilize and sustain public support for military operations and demonstrate empirically that these conditions apply in the Danish case. The secret Danish recipe for maintaining support for the Afghan war thus came...... down to the government’s ability to craft a strategic narrative that met the conditions for success stipulated by our framework....

  12. Conclusion: How to operate strategic narratives. Interweaving war, politics, and the public

    DEFF Research Database (Denmark)

    Jakobsen, Peter Viggo; Ringsmose, Jens

    2015-01-01

    conditions for success from these literatures that governments must be able to meet in order to mobilize and sustain public support for military operations and demonstrate empirically that these conditions apply in the Danish case. The secret Danish recipe for maintaining support for the Afghan war thus came...... down to the government’s ability to craft a strategic narrative that met the conditions for success stipulated by our framework....

  13. Considerations for rice fortification in public health: conclusions of a technical consultation.

    Science.gov (United States)

    De-Regil, Luz M; Peña-Rosas, Juan Pablo; Laillou, Arnaud; Moench-Pfanner, Regina

    2014-09-01

    Fortification of staple foods and commonly used condiments with vitamins and minerals has been considered one of the most cost-effective interventions to prevent and control micronutrient deficiencies. Because of its wide local consumption, acceptability, reach, and quantum of consumption, rice (Oryza sativa) far exceeds the requirements of a staple food vehicle that can be considered for fortification purposes at a population-level intervention. The World Health Organization (WHO) has the mandate to develop evidence-informed guidelines for the fortification of staple foods as a public health intervention, including rice fortification with micronutrients. The WHO, in collaboration with the Global Alliance for Improved Nutrition (GAIN), convened a consultation on "Technical Considerations for Rice Fortification in Public Health" in Geneva, Switzerland on October 9-10, 2012 to provide technical inputs to the guideline development process, particularly with reference to feasibility and implementability. The industrial and regulatory technical considerations in rice fortification, as well as the considerations for implementing it as a public health strategy and assuring equitable access and universal coverage, were reviewed in this consultation. This paper summarizes the discussions and priority research areas for the forthcoming years.

  14. Misunderstanding publication bias: editors are not blameless after all.

    Science.gov (United States)

    Senn, Stephen

    2012-01-01

    In analysing whether there is an editorial bias in favour of positive studies, researchers have made implicit assumptions that are implausible. In particular, to justify the conclusion that there is no bias because observed editorial acceptance rates do not favour positive studies, the assumption that the decision to submit an article is based solely on quality would be required. If, on the other hand, submission were based on perceived probability of acceptance, negative and positive studies would not differ in terms of acceptance rates, but in terms of quality. It is shown, using a simple graphical model, how similar underlying situations as regards the relationship between quality and probability of acceptance on the one hand and study outcome (positive or negative) and probability of acceptance on the other could produce dramatically different results depending on the behaviour of authors. Furthermore, there is, in fact, some evidence that submitted negative studies are, on average, of higher quality than positive ones. This calls into question the standard interpretation of the studies examining editorial bias. It would appear that despite similar probabilities of acceptance for negative and positive studies, editors could be discriminating against negative studies.

  15. The LIFE Project “Monitoring of insects with public participation” (MIPP: aims, methods and conclusions

    Directory of Open Access Journals (Sweden)

    Giuseppe Maria Carpaneto

    2017-08-01

    Full Text Available The Life Project “Monitoring of insects with public participation” (LIFE11 NAT/IT/000252 had as the main objective to develop and test methods for the monitoring of five beetle species listed in the Annexes of the Habitats Directive (92/43/EEC: Osmoderma eremita (hermit beetle, Scarabaeidae, Lucanus cervus (European stag beetle, Lucanidae, Cerambyx cerdo (great capricorn beetle, Cerambycidae, Rosalia alpina (rosalia longicorn, Cerambycidae and Morimus asper/funereus (morimus longicorn, Cerambycidae. The data gathered represent an important contribution to the monitoring of these target species in Italy. The methods developed for monitoring of the target species are intended for use by the local management authorities and staff of protected areas. These developed methods are the result of extensive fieldwork and ensure scientific validity, ease of execution and limited labour costs. The detailed description of methods and the results for each species are published in separate articles of this special issue of Nature Conservation. A second objective of the project was to gather faunistic data with a Citizen Science approach, using the web and a mobile application software (app specifically built for mobile devices. The validation of the records collected by the citizens was carried out by experts, based on photographs, which were obligatory for all records. Dissemination activities represented the principal way to contact and engage citizens for the data collection and also offered the possibility of providing information on topics such as Natura 2000, the Habitats Directive, the role of monitoring in nature conservation, the importance of forest ecosystems and the ecological role of the saproxylic insects. An innovative method tested during the project was the training of a dog for searching and monitoring the elusive hermit beetle; the trained dog also added a “curiosity” factor to attract public attention towards this rare insect and

  16. Non-publication and publication bias in reproductive medicine: a cohort analysis.

    Science.gov (United States)

    Lensen, S; Jordan, V; Showell, M; Showell, E; Shen, V; Venetis, C; Farquhar, C

    2017-08-01

    Does publication bias or non-publication exist in fertility trials presented as conference abstracts? This study did not detect any publication bias; however, it did identify a high level of non-publication, with only 49% of abstracts reaching full-text publication four or more years after abstract presentation. Systematic reviews of randomized controlled trials (RCTs) are the foundation of evidence based medicine. Non-publication or publication deficit refer to the failure to publish trial results. A publication bias exists when there is any tendency on the parts of the investigators or editors to fail to publish study results on the basis or strength of the study findings. Both present a serious problem for researchers, clinicians and policymakers alike, and ultimately impact on patient care. A retrospective cohort study identified 337 fertility RCTs presented as conference abstracts between 2007 and 2010, as captured by an electronic search of the Cochrane Gynaecology and Fertility Database. After excluding ineligible trials and duplicates, 224 abstracts remained. A search for the full-text papers of each abstract was undertaken in Pubmed, MEDLINE, Embase, CINAHL and Google in May 2015 using a probabilistic approach. Trial authors were contacted to query the publication status of abstracts when no full-text was identified. The association between individual variables and the probability of publication, and time to publication, was assessed using logistic regression and Cox regression, respectively. Of the 224 included abstracts, only 110 (49%; 95% CI: 42.6, 55.6) were found to be published as full-text articles. Publication bias was not identified in this cohort; studies with positive results had a similar probability of reaching full-text publication 52/113 (46%; 95% CI: 37.0, 55.3) as studies with non-positive (negative or null) results 58/111 (52%; 95% CI: 17.8, 33.9) (adjusted odds ratio (AOR): 1.02; 95% CI: 0.53, 1.97). Similarly, the time from abstract

  17. Galvanizing action: conclusions and next steps for mainstreaming zinc interventions in public health programs.

    Science.gov (United States)

    Brown, Kenneth H; Baker, Shawn K

    2009-03-01

    This paper summarizes the results of the foregoing reviews of the impact of different intervention strategies designed to enhance zinc nutrition, including supplementation, fortification, and dietary diversification or modification. Current evidence indicates a beneficial impact of such interventions on zinc status and zinc-related functional outcomes. Preventive zinc supplementation reduces the incidence of diarrhea and acute lower respiratory tract infection among young children, decreases mortality of children over 12 months of age, and increases growth velocity. Therapeutic zinc supplementation during episodes of diarrhea reduces the duration and severity of illness. Zinc fortification increases zinc intake and total absorbed zinc, and recent studies are beginning to confirm a positive impact of zinc fortification on indicators of population zinc status. To assist with the development of zinc intervention programs, more information is needed on the prevalence of zinc deficiency in different countries, and rigorous evaluations of the effectiveness of large-scale zinc intervention programs should be planned. Recommended steps for scaling up zinc intervention programs, with or without other micronutrients, are described. In summary, there is now clear evidence of the benefit of selected interventions to reduce the risk of zinc deficiency, and a global commitment is urgently needed to conduct systematic assessments of population zinc status and to develop interventions to control zinc deficiency in the context of existing public health and nutrition programs.

  18. Publication bias and the canonization of false facts.

    Science.gov (United States)

    Nissen, Silas Boye; Magidson, Tali; Gross, Kevin; Bergstrom, Carl T

    2016-12-20

    Science is facing a "replication crisis" in which many experimental findings cannot be replicated and are likely to be false. Does this imply that many scientific facts are false as well? To find out, we explore the process by which a claim becomes fact. We model the community's confidence in a claim as a Markov process with successive published results shifting the degree of belief. Publication bias in favor of positive findings influences the distribution of published results. We find that unless a sufficient fraction of negative results are published, false claims frequently can become canonized as fact. Data-dredging, p-hacking, and similar behaviors exacerbate the problem. Should negative results become easier to publish as a claim approaches acceptance as a fact, however, true and false claims would be more readily distinguished. To the degree that the model reflects the real world, there may be serious concerns about the validity of purported facts in some disciplines.

  19. Investment, managerial capacity, and bias in public health preparedness.

    Science.gov (United States)

    Langabeer, James R; DelliFraine, Jami L; Tyson, Sandra; Emert, Jamie M; Herbold, John

    2009-01-01

    Nearly $7 billion has been invested through national cooperative funding since 2002 to strengthen state and local response capacity. Yet, very little outcome evidence exists to analyze funding effectiveness. The objective of this research is to analyze the relationship between investment (funding) and capacity (readiness) for public health preparedness (PHP). The aim of the authors is to use a management framework to evaluate capacity, and to explore the "immediacy bias" impact on investment stability. This study employs a longitudinal study design, incorporating survey research of the entire population of 68 health departments in the state of Texas. The authors assessed the investment-capacity relationship through several statistical methods. The authors created a structural measure of managerial capacity through principal components analysis, factorizing 10 independent variables and augment this with a perceived readiness level reported from PHP managers. The authors then employ analysis of variance, correlation analyses, and other descriptive statistics. There has been a 539 percent coefficient of variation in funding at the local level between the years 2004 and 2008, and a 63 percent reduction in total resources since the peak of funding, using paired sample data. Results suggest that investment is positively associated with readiness and managerial capacity in local health departments. The authors also find that investment was related to greater community collaboration, higher adoption of Incident Command System (ICS) structure, and more frequent operational drills and exercises. Greater investment is associated with higher levels of capacity and readiness. The authors conclude from this that investment should be stabilized and continued, and not be influenced by historical cognitive biases.

  20. Publication Bias in Psychology: A Diagnosis Based on the Correlation between Effect Size and Sample Size

    Science.gov (United States)

    Kühberger, Anton; Fritz, Astrid; Scherndl, Thomas

    2014-01-01

    Background The p value obtained from a significance test provides no information about the magnitude or importance of the underlying phenomenon. Therefore, additional reporting of effect size is often recommended. Effect sizes are theoretically independent from sample size. Yet this may not hold true empirically: non-independence could indicate publication bias. Methods We investigate whether effect size is independent from sample size in psychological research. We randomly sampled 1,000 psychological articles from all areas of psychological research. We extracted p values, effect sizes, and sample sizes of all empirical papers, and calculated the correlation between effect size and sample size, and investigated the distribution of p values. Results We found a negative correlation of r = −.45 [95% CI: −.53; −.35] between effect size and sample size. In addition, we found an inordinately high number of p values just passing the boundary of significance. Additional data showed that neither implicit nor explicit power analysis could account for this pattern of findings. Conclusion The negative correlation between effect size and samples size, and the biased distribution of p values indicate pervasive publication bias in the entire field of psychology. PMID:25192357

  1. Publication Bias in Meta-Analyses of the Efficacy of Psychotherapeutic Interventions for Depression

    Science.gov (United States)

    Niemeyer, Helen; Musch, Jochen; Pietrowsky, Reinhard

    2013-01-01

    Objective: The aim of this study was to assess whether systematic reviews investigating psychotherapeutic interventions for depression are affected by publication bias. Only homogeneous data sets were included, as heterogeneous data sets can distort statistical tests of publication bias. Method: We applied Begg and Mazumdar's adjusted rank…

  2. Too good to be true: publication bias in two prominent studies from experimental psychology.

    Science.gov (United States)

    Francis, Gregory

    2012-04-01

    Empirical replication has long been considered the final arbiter of phenomena in science, but replication is undermined when there is evidence for publication bias. Evidence for publication bias in a set of experiments can be found when the observed number of rejections of the null hypothesis exceeds the expected number of rejections. Application of this test reveals evidence of publication bias in two prominent investigations from experimental psychology that have purported to reveal evidence of extrasensory perception and to indicate severe limitations of the scientific method. The presence of publication bias suggests that those investigations cannot be taken as proper scientific studies of such phenomena, because critical data are not available to the field. Publication bias could partly be avoided if experimental psychologists started using Bayesian data analysis techniques.

  3. Publication and other reporting biases in cognitive sciences: detection, prevalence, and prevention.

    Science.gov (United States)

    Ioannidis, John P A; Munafò, Marcus R; Fusar-Poli, Paolo; Nosek, Brian A; David, Sean P

    2014-05-01

    Recent systematic reviews and empirical evaluations of the cognitive sciences literature suggest that publication and other reporting biases are prevalent across diverse domains of cognitive science. In this review, we summarize the various forms of publication and reporting biases and other questionable research practices, and overview the available methods for probing into their existence. We discuss the available empirical evidence for the presence of such biases across the neuroimaging, animal, other preclinical, psychological, clinical trials, and genetics literature in the cognitive sciences. We also highlight emerging solutions (from study design to data analyses and reporting) to prevent bias and improve the fidelity in the field of cognitive science research.

  4. GENDER BIAS IN THE PUBLIC RELATIONS INDUSTRY IN MALAYSIA: COMPARING PUBLIC RELATIONS PRACTITIONERS’ JOB FUNCTIONS, INCOMES, AND CAREER PROSPECTS

    OpenAIRE

    Yesuselvi Manickam; Tan Soon Chin; Suffian Hadi Ayub

    2016-01-01

    Today, there is an increase in women working outside their home to sustain themselves economically and socially, but the working experiences can be problematic for women when gender discrimination exists in the workplace. In the early 1960s, women were entering the public relations industry at a rate faster than their male counterparts, but gender bias was a sore issue in the industry. Numerous studies have been conducted on gender bias, and the findings indicate that female public relations ...

  5. 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 hypothes

  6. Sweet Conclusion

    Science.gov (United States)

    Shirley, Britt M.; Wooldridge, Barbara Ross; Camp, Kerri M.

    2012-01-01

    Jen Harrington is the owner and pastry chef of Sweet Conclusion, a bakery in Tampa, Florida. Most of Harrington's business comes from baking wedding cakes, but she has been attempting to attract customers to her retail bakery, where she sells cupcakes, pies, ice cream, and coffee. Nearly four years she opened Sweet Conclusion, the retail part of…

  7. GENDER BIAS IN THE PUBLIC RELATIONS INDUSTRY IN MALAYSIA: COMPARING PUBLIC RELATIONS PRACTITIONERS’ JOB FUNCTIONS, INCOMES, AND CAREER PROSPECTS

    Directory of Open Access Journals (Sweden)

    Yesuselvi Manickam

    2016-12-01

    Full Text Available Today, there is an increase in women working outside their home to sustain themselves economically and socially, but the working experiences can be problematic for women when gender discrimination exists in the workplace. In the early 1960s, women were entering the public relations industry at a rate faster than their male counterparts, but gender bias was a sore issue in the industry. Numerous studies have been conducted on gender bias, and the findings indicate that female public relations practitioners receive unequal treatment in their organisation. For that reason, this study investigated whether gender bias exists in the public relations industry in Klang Valley, Malaysia, and if so, what the impact was on the practitioners’ work performance. The study used an in-depth interview with five public relations practitioners from public relations agencies and corporate companies. Feminist Standpoint Theory served as a framework for this study. Results revealed that in Malaysia, gender bias is not prevalent because of cultural diversity and company policies. The priorities of these public relations agencies and organisations favor employee’s performance and competence over gender. The results also indicated that public relations practitioners are treated fairly in areas of career prospects, job functions, and remuneration.

  8. Dominant Personality Types in Public Accounting: Selection Bias or Indoctrinated?

    Science.gov (United States)

    Burton, Hughlene; Daugherty, Brian; Dickins, Denise; Schisler, Dan

    2016-01-01

    Prior studies concerning the personality type and preferences of accountants generally draw conclusions based upon the reports of either practicing accountants, or accounting students, at a single point in time. So while much is known about the personality type of accountants in general, left unexplored is the question of whether public…

  9. Social science. Publication bias in the social sciences: unlocking the file drawer.

    Science.gov (United States)

    Franco, Annie; Malhotra, Neil; Simonovits, Gabor

    2014-09-19

    We studied publication bias in the social sciences by analyzing a known population of conducted studies--221 in total--in which there is a full accounting of what is published and unpublished. We leveraged Time-sharing Experiments in the Social Sciences (TESS), a National Science Foundation-sponsored program in which researchers propose survey-based experiments to be run on representative samples of American adults. Because TESS proposals undergo rigorous peer review, the studies in the sample all exceed a substantial quality threshold. Strong results are 40 percentage points more likely to be published than are null results and 60 percentage points more likely to be written up. We provide direct evidence of publication bias and identify the stage of research production at which publication bias occurs: Authors do not write up and submit null findings.

  10. Publication Bias and Nonreporting Found in Majority of Systematic Reviews and Meta-analyses in Anesthesiology Journals.

    Science.gov (United States)

    Hedin, Riley J; Umberham, Blake A; Detweiler, Byron N; Kollmorgen, Lauren; Vassar, Matt

    2016-10-01

    Systematic reviews and meta-analyses are used by clinicians to derive treatment guidelines and make resource allocation decisions in anesthesiology. One cause for concern with such reviews is the possibility that results from unpublished trials are not represented in the review findings or data synthesis. This problem, known as publication bias, results when studies reporting statistically nonsignificant findings are left unpublished and, therefore, not included in meta-analyses when estimating a pooled treatment effect. In turn, publication bias may lead to skewed results with overestimated effect sizes. The primary objective of this study is to determine the extent to which evaluations for publication bias are conducted by systematic reviewers in highly ranked anesthesiology journals and which practices reviewers use to mitigate publication bias. The secondary objective of this study is to conduct publication bias analyses on the meta-analyses that did not perform these assessments and examine the adjusted pooled effect estimates after accounting for publication bias. This study considered meta-analyses and systematic reviews from 5 peer-reviewed anesthesia journals from 2007 through 2015. A PubMed search was conducted, and full-text systematic reviews that fit inclusion criteria were downloaded and coded independently by 2 authors. Coding was then validated, and disagreements were settled by consensus. In total, 207 systematic reviews were included for analysis. In addition, publication bias evaluation was performed for 25 systematic reviews that did not do so originally. We used Egger regression, Duval and Tweedie trim and fill, and funnel plots for these analyses. Fifty-five percent (n = 114) of the reviews discussed publication bias, and 43% (n = 89) of the reviews evaluated publication bias. Funnel plots and Egger regression were the most common methods for evaluating publication bias. Publication bias was reported in 34 reviews (16%). Thirty-six of the 45

  11. When are statins cost-effective in cardiovascular prevention? A systematic review of sponsorship bias and conclusions in economic evaluations of statins.

    Directory of Open Access Journals (Sweden)

    Ferrán Catalá-López

    Full Text Available BACKGROUND: We examined sponsorship of published cost-effectiveness analyses of statin use for cardiovascular (CV prevention, and determined whether the funding source is associated with study conclusions. METHODS AND FINDINGS: We searched PubMed/MEDLINE (up to June 2011 to identify cost-effectiveness analyses of statin use for CV prevention reporting outcomes as incremental costs per quality-adjusted life years (QALY and/or life years gained (LYG. We examined relationships between the funding source and the study conclusions by means of tests of differences between proportions. Seventy-five studies were included. Forty-eight studies (64.0% were industry-sponsored. Fifty-two (69.3% articles compared statins versus non-active alternatives. Secondary CV prevention represented 42.7% of articles, followed by primary CV prevention (38.7% and both (18.7%. Overall, industry-sponsored studies were much less likely to report unfavourable or neutral conclusions (0% versus 37.1%; p<0.001. For primary CV prevention, the proportion with unfavourable or neutral conclusions was 0% for industry-sponsored studies versus 57.9% for non-sponsored studies (p<0.001. Conversely, no statistically significant differences were identified for studies evaluating secondary CV prevention (0% versus 12.5%; p=0.222. Incremental costs per QALY/LYG estimates reported in industry-sponsored studies were generally more likely to fall below a hypothetical willingness-to-pay threshold of US $50,000. CONCLUSIONS: Our systematic analysis suggests that pharmaceutical industry sponsored economic evaluations of statins have generally favored the cost-effectiveness profile of their products particularly in primary CV prevention.

  12. Students' Race and Teachers' Social Support Affect the Positive Feedback Bias in Public Schools

    Science.gov (United States)

    Harber, Kent D.; Gorman, Jamie L.; Gengaro, Frank P.; Butisingh, Samantha; Tsang, William; Ouellette, Rebecca

    2012-01-01

    This research tested whether public school teachers display the positive feedback bias, wherein Whites give more praise and less criticism to minorities than to fellow Whites for equivalent work. It also tested whether teachers lacking in school-based social support (i.e., support from fellow teachers and school administrators) are more likely to…

  13. What happened to Popperian falsification? Publishing neutral and negative findings : Moving away from biased publication practices

    NARCIS (Netherlands)

    van Witteloostuijn, Arjen

    2016-01-01

    Purpose – Current publication practices in the scholarly (International) Business and Management community are overwhelmingly anti-Popperian, which fundamentally frustrates the production of scientific progress. This is the result of at least five related biases: the verification, novelty, normal sc

  14. What happened to Popperian falsification? Publishing neutral and negative findings : Moving away from biased publication practices

    NARCIS (Netherlands)

    van Witteloostuijn, Arjen

    2016-01-01

    Purpose – Current publication practices in the scholarly (International) Business and Management community are overwhelmingly anti-Popperian, which fundamentally frustrates the production of scientific progress. This is the result of at least five related biases: the verification, novelty, normal sc

  15. Is grey literature essential for a better control of publication bias in psychiatry? An example from three meta-analyses of schizophrenia.

    Science.gov (United States)

    Martin, José Luis R; Pérez, Víctor; Sacristán, Montse; Alvarez, Enric

    2005-12-01

    Systematic reviews in mental health have become useful tools for health professionals in view of the massive amount and heterogeneous nature of biomedical information available today. In order to determine the risk of bias in the studies evaluated and to avoid bias in generalizing conclusions from the reviews it is therefore important to use a very strict methodology in systematic reviews. One bias which may affect the generalization of results is publication bias, which is determined by the nature and direction of the study results. To control or minimize this type of bias, the authors of systematic reviews undertake comprehensive searches of medical databases and expand on the findings, often undertaking searches of grey literature (material which is not formally published). This paper attempts to show the consequences (and risk) of generalizing the implications of grey literature in the control of publication bias, as was proposed in a recent systematic work. By repeating the analyses for the same outcome from three different systematic reviews that included both published and grey literature our results showed that confusion between grey literature and publication bias may affect the results of a concrete meta-analysis.

  16. Publication bias in "Red, rank, and romance in women viewing men," by Elliot et al. (2010).

    Science.gov (United States)

    Francis, Gregory

    2013-02-01

    Elliot et al. (2010) reported multiple experimental findings that the color red modified women's ratings of attractiveness, sexual desirability, and status of a photographed man. An analysis of the reported statistics of these studies indicates that the experiments lack sufficient power to support these claims. Given the power of the experiments, the probability that the observed 12 findings would all reject the null hypothesis is only .005. Thus, the proper interpretation of the findings is that the studies are contaminated with publication bias. Either some experiments with null findings were not reported or the reported experiments were run improperly in a way that inflated the likelihood of rejecting the null hypothesis. Because of the presence of publication bias, the findings in Elliot et al. (2010) should be considered nonscientific or anecdotal. It remains an open question whether the color red influences women's ratings of men's attributes. 2013 APA, all rights reserved

  17. Exercise as a treatment for depression: A meta-analysis adjusting for publication bias.

    Science.gov (United States)

    Schuch, Felipe B; Vancampfort, Davy; Richards, Justin; Rosenbaum, Simon; Ward, Philip B; Stubbs, Brendon

    2016-06-01

    The effects of exercise on depression have been a source of contentious debate. Meta-analyses have demonstrated a range of effect sizes. Both inclusion criteria and heterogeneity may influence the effect sizes reported. The extent and influence of publication bias is also unknown. Randomized controlled trials (RCTs) were identified from a recent Cochrane review and searches of major electronic databases from 01/2013 to 08/2015. We included RCTs of exercise interventions in people with depression (including those with a diagnosis of major depressive disorder (MDD) or ratings on depressive symptoms), comparing exercise versus control conditions. A random effects meta-analysis calculating the standardized mean difference (SMD, 95% confidence interval; CI), meta-regressions, trim and fill and fail-safe n analyses were conducted. Twenty-five RCTs were included comparing exercise versus control comparison groups, including 9 examining participants with MDD. Overall, exercise had a large and significant effect on depression (SMD adjusted for publication bias = 1.11 (95% CI 0.79-1.43)) with a fail-safe number of 1057. Most adjusted analyses suggested publication bias led to an underestimated SMD. Larger effects were found for interventions in MDD, utilising aerobic exercise, at moderate and vigorous intensities, in a supervised and unsupervised format. In MDD, larger effects were found for moderate intensity, aerobic exercise, and interventions supervised by exercise professionals. Exercise has a large and significant antidepressant effect in people with depression (including MDD). Previous meta-analyses may have underestimated the benefits of exercise due to publication bias. Our data strongly support the claim that exercise is an evidence-based treatment for depression.

  18. Bias analysis applied to Agricultural Health Study publications to estimate non-random sources of uncertainty

    Directory of Open Access Journals (Sweden)

    Lash Timothy L

    2007-11-01

    Full Text Available Abstract Background The associations of pesticide exposure with disease outcomes are estimated without the benefit of a randomized design. For this reason and others, these studies are susceptible to systematic errors. I analyzed studies of the associations between alachlor and glyphosate exposure and cancer incidence, both derived from the Agricultural Health Study cohort, to quantify the bias and uncertainty potentially attributable to systematic error. Methods For each study, I identified the prominent result and important sources of systematic error that might affect it. I assigned probability distributions to the bias parameters that allow quantification of the bias, drew a value at random from each assigned distribution, and calculated the estimate of effect adjusted for the biases. By repeating the draw and adjustment process over multiple iterations, I generated a frequency distribution of adjusted results, from which I obtained a point estimate and simulation interval. These methods were applied without access to the primary record-level dataset. Results The conventional estimates of effect associating alachlor and glyphosate exposure with cancer incidence were likely biased away from the null and understated the uncertainty by quantifying only random error. For example, the conventional p-value for a test of trend in the alachlor study equaled 0.02, whereas fewer than 20% of the bias analysis iterations yielded a p-value of 0.02 or lower. Similarly, the conventional fully-adjusted result associating glyphosate exposure with multiple myleoma equaled 2.6 with 95% confidence interval of 0.7 to 9.4. The frequency distribution generated by the bias analysis yielded a median hazard ratio equal to 1.5 with 95% simulation interval of 0.4 to 8.9, which was 66% wider than the conventional interval. Conclusion Bias analysis provides a more complete picture of true uncertainty than conventional frequentist statistical analysis accompanied by a

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

    Science.gov (United States)

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

    2016-10-01

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

  20. A selection model for accounting for publication bias in a full network meta-analysis.

    Science.gov (United States)

    Mavridis, Dimitris; Welton, Nicky J; Sutton, Alex; Salanti, Georgia

    2014-12-30

    Copas and Shi suggested a selection model to explore the potential impact of publication bias via sensitivity analysis based on assumptions for the probability of publication of trials conditional on the precision of their results. Chootrakool et al. extended this model to three-arm trials but did not fully account for the implications of the consistency assumption, and their model is difficult to generalize for complex network structures with more than three treatments. Fitting these selection models within a frequentist setting requires maximization of a complex likelihood function, and identification problems are common. We have previously presented a Bayesian implementation of the selection model when multiple treatments are compared with a common reference treatment. We now present a general model suitable for complex, full network meta-analysis that accounts for consistency when adjusting results for publication bias. We developed a design-by-treatment selection model to describe the mechanism by which studies with different designs (sets of treatments compared in a trial) and precision may be selected for publication. We fit the model in a Bayesian setting because it avoids the numerical problems encountered in the frequentist setting, it is generalizable with respect to the number of treatments and study arms, and it provides a flexible framework for sensitivity analysis using external knowledge. Our model accounts for the additional uncertainty arising from publication bias more successfully compared to the standard Copas model or its previous extensions. We illustrate the methodology using a published triangular network for the failure of vascular graft or arterial patency.

  1. Publication bias in psychology: a diagnosis based on the correlation between effect size and sample size.

    Directory of Open Access Journals (Sweden)

    Anton Kühberger

    Full Text Available The p value obtained from a significance test provides no information about the magnitude or importance of the underlying phenomenon. Therefore, additional reporting of effect size is often recommended. Effect sizes are theoretically independent from sample size. Yet this may not hold true empirically: non-independence could indicate publication bias.We investigate whether effect size is independent from sample size in psychological research. We randomly sampled 1,000 psychological articles from all areas of psychological research. We extracted p values, effect sizes, and sample sizes of all empirical papers, and calculated the correlation between effect size and sample size, and investigated the distribution of p values.We found a negative correlation of r = -.45 [95% CI: -.53; -.35] between effect size and sample size. In addition, we found an inordinately high number of p values just passing the boundary of significance. Additional data showed that neither implicit nor explicit power analysis could account for this pattern of findings.The negative correlation between effect size and samples size, and the biased distribution of p values indicate pervasive publication bias in the entire field of psychology.

  2. Exposure reduces negative bias in self-rated performance in public speaking fearful participants.

    Science.gov (United States)

    Cheng, Joyce; Niles, Andrea N; Craske, Michelle G

    2017-03-01

    Individuals with public speaking anxiety (PSA) under-rate their performance compared to objective observers. The present study examined whether exposure reduces the discrepancy between self and observer performance ratings and improved observer-rated performance in individuals with PSA. PSA participants gave a speech in front of a small audience and rated their performance using a questionnaire before and after completing repeated exposures to public speaking. Non-anxious control participants gave a speech and completed the questionnaire one time only. Objective observers watched videos of the speeches and rated performance using the same questionnaire. PSA participants underrated their performance to a greater degree than did controls prior to exposure, but also performed significantly more poorly than did controls when rated objectively. Bias significantly decreased and objective-rated performance significantly increased following completion of exposure in PSA participants, and on one performance measure, anxious participants no longer showed a greater discrepancy between self and observer performance ratings compared to controls. The study employed non-clinical student sample, but the results should be replicated in clinical anxiety samples. These findings indicate that exposure alone significantly reduces negative performance bias among PSA individuals, but additional exposure or additional interventions may be necessary to fully correct bias and performance deficits. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Exercise for depression in older adults: a meta-analysis of randomized controlled trials adjusting for publication bias

    Directory of Open Access Journals (Sweden)

    Felipe B. Schuch

    Full Text Available Objective: To evaluate the antidepressant effects of exercise in older adults, using randomized controlled trial (RCT data. Methods: We conducted a meta-analysis of exercise in older adults, addressing limitations of previous works. RCTs of exercise interventions in older people with depression (≥ 60 years comparing exercise vs. control were eligible. A random-effects meta-analysis calculating the standardized mean difference (SMD (95% confidence interval [95%CI], meta-regressions, and trim, fill, and fail-safe number analyses were conducted. Results: Eight RCTs were included, representing 138 participants in exercise arms and 129 controls. Exercise had a large and significant effect on depression (SMD = -0.90 [95%CI -0.29 to -1.51], with a fail-safe number of 71 studies. Significant effects were found for 1 mixed aerobic and anaerobic interventions, 2 at moderate intensity, 3 that were group-based, 4 that utilized mixed supervised and unsupervised formats, and 5 in people without other clinical comorbidities. Conclusion: Adjusting for publication bias increased the beneficial effects of exercise in three subgroup analysis, suggesting that previous meta-analyses have underestimated the benefits of exercise due to publication bias. We advocate that exercise be considered as a routine component of the management of depression in older adults.

  4. Bias in research.

    Science.gov (United States)

    Simundić, Ana-Maria

    2013-01-01

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

  5. Randomly biased investments and the evolution of public goods on interdependent networks

    Science.gov (United States)

    Chen, Wei; Wu, Te; Li, Zhiwu; Wang, Long

    2017-08-01

    Deciding how to allocate resources between interdependent systems is significant to optimize efficiency. We study the effects of heterogeneous contribution, induced by such interdependency, on the evolution of cooperation, through implementing the public goods games on two-layer networks. The corresponding players on different layers try to share a fixed amount of resources as the initial investment properly. The symmetry breaking of investments between players located on different layers is able to either prevent investments from, or extract them out of the deadlock. Results show that a moderate investment heterogeneity is best favorable for the evolution of cooperation, and random allocation of investment bias suppresses the cooperators at a wide range of the investment bias and the enhancement effect. Further studies on time evolution with different initial strategy configurations show that the non-interdependent cooperators along the interface of interdependent cooperators also are an indispensable factor in facilitating cooperative behavior. Our main results are qualitatively unchanged even diversifying investment bias that is subject to uniform distribution. Our study may shed light on the understanding of the origin of cooperative behavior on interdependent networks.

  6. Role of Editorial and Peer Review Processes in Publication Bias: Analysis of Drug Trials Submitted to Eight Medical Journals

    Science.gov (United States)

    van Lent, Marlies; Overbeke, John; Out, Henk Jan

    2014-01-01

    Background Publication bias is generally ascribed to authors and sponsors failing to submit studies with negative results, but may also occur after submission. We evaluated whether submitted manuscripts on randomized controlled trials (RCTs) with drugs are more likely to be accepted if they report positive results. Methods Manuscripts submitted from January 2010 through April 2012 to one general medical journal (BMJ) and seven specialty journals (Annals of the Rheumatic Diseases, British Journal of Ophthalmology, Gut, Heart, Thorax, Diabetologia, and Journal of Hepatology) were included, if at least one study arm assessed the efficacy or safety of a drug and a statistical test was used to evaluate treatment effects. Publication status was retrospectively retrieved from submission systems or provided by journals. Sponsorship and trial results were extracted from manuscripts and classified according to predefined criteria. Main outcome measure was acceptance for publication. Results Of 15,972 manuscripts submitted, 472 (3.0%) were drug RCTs, of which 98 (20.8%) were published. Among submitted drug RCTs, 287 (60.8%) had positive and 185 (39.2%) negative results. Of these, 60 (20.9%) and 38 (20.5%), respectively, were published. Manuscripts on non-industry trials (n = 213) reported positive results in 138 (64.8%) manuscripts, compared to 71 (47.7%) on industry-supported trials (n = 149), and 78 (70.9%) on industry-sponsored trials (n = 110). Twenty-seven (12.7%) non-industry trials were published, compared to 27 (18.1%) industry-supported and 44 (40.0%) industry-sponsored trials. After adjustment for other trial characteristics, manuscripts reporting positive results were not more likely to be published (OR, 1.00; 95% CI, 0.61 to 1.66). Submission to specialty journals, sample size, multicentre status, journal impact factor, and corresponding authors from Europe or US were significantly associated with publication. Conclusions For the selected journals

  7. How evidence-based medicine is failing due to biased trials and selective publication.

    Science.gov (United States)

    Every-Palmer, Susanna; Howick, Jeremy

    2014-12-01

    Evidence-based medicine (EBM) was announced in the early 1990s as a 'new paradigm' for improving patient care. Yet there is currently little evidence that EBM has achieved its aim. Since its introduction, health care costs have increased while there remains a lack of high-quality evidence suggesting EBM has resulted in substantial population-level health gains. In this paper we suggest that EBM's potential for improving patients' health care has been thwarted by bias in the choice of hypotheses tested, manipulation of study design and selective publication. Evidence for these flaws is clearest in industry-funded studies. We argue EBM's indiscriminate acceptance of industry-generated 'evidence' is akin to letting politicians count their own votes. Given that most intervention studies are industry funded, this is a serious problem for the overall evidence base. Clinical decisions based on such evidence are likely to be misinformed, with patients given less effective, harmful or more expensive treatments. More investment in independent research is urgently required. Independent bodies, informed democratically, need to set research priorities. We also propose that evidence rating schemes are formally modified so research with conflict of interest bias is explicitly downgraded in value. © 2014 John Wiley & Sons, Ltd.

  8. 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

  9. Clustering of Local Group distances: publication bias or correlated measurements? I. The Large Magellanic Cloud

    CERN Document Server

    de Grijs, Richard; Bono, Giuseppe

    2014-01-01

    The distance to the Large Magellanic Cloud (LMC) represents a key local rung of the extragalactic distance ladder. Yet, the galaxy's distance modulus has long been an issue of contention, in particular in view of claims that most newly determined distance moduli cluster tightly - and with a small spread - around the "canonical" distance modulus, (m-M)_0 = 18.50 mag. We compiled 233 separate LMC distance determinations published between 1990 and 2013. Our analysis of the individual distance moduli, as well as of their two-year means and standard deviations resulting from this largest data set of LMC distance moduli available to date, focuses specifically on Cepheid and RR Lyrae variable-star tracer populations, as well as on distance estimates based on features in the observational Hertzsprung-Russell diagram. We conclude that strong publication bias is unlikely to have been the main driver of the majority of published LMC distance moduli. However, for a given distance tracer, the body of publications leading ...

  10. Estimates of the average strength of natural selection are not inflated by sampling error or publication bias.

    Science.gov (United States)

    Knapczyk, Frances N; Conner, Jeffrey K

    2007-10-01

    Kingsolver et al.'s review of phenotypic selection gradients from natural populations provided a glimpse of the form and strength of selection in nature and how selection on different organisms and traits varies. Because this review's underlying database could be a key tool for answering fundamental questions concerning natural selection, it has spawned discussion of potential biases inherent in the review process. Here, we explicitly test for two commonly discussed sources of bias: sampling error and publication bias. We model the relationship between variance among selection gradients and sample size that sampling error produces by subsampling large empirical data sets containing measurements of traits and fitness. We find that this relationship was not mimicked by the review data set and therefore conclude that sampling error does not bias estimations of the average strength of selection. Using graphical tests, we find evidence for bias against publishing weak estimates of selection only among very small studies (N<38). However, this evidence is counteracted by excess weak estimates in larger studies. Thus, estimates of average strength of selection from the review are less biased than is often assumed. Devising and conducting straightforward tests for different biases allows concern to be focused on the most troublesome factors.

  11. Estimating and modelling bias of the hierarchical partitioning public-domain software: implications in environmental management and conservation.

    Directory of Open Access Journals (Sweden)

    Pedro P Olea

    Full Text Available BACKGROUND: Hierarchical partitioning (HP is an analytical method of multiple regression that identifies the most likely causal factors while alleviating multicollinearity problems. Its use is increasing in ecology and conservation by its usefulness for complementing multiple regression analysis. A public-domain software "hier.part package" has been developed for running HP in R software. Its authors highlight a "minor rounding error" for hierarchies constructed from >9 variables, however potential bias by using this module has not yet been examined. Knowing this bias is pivotal because, for example, the ranking obtained in HP is being used as a criterion for establishing priorities of conservation. METHODOLOGY/PRINCIPAL FINDINGS: Using numerical simulations and two real examples, we assessed the robustness of this HP module in relation to the order the variables have in the analysis. Results indicated a considerable effect of the variable order on the amount of independent variance explained by predictors for models with >9 explanatory variables. For these models the nominal ranking of importance of the predictors changed with variable order, i.e. predictors declared important by its contribution in explaining the response variable frequently changed to be either most or less important with other variable orders. The probability of changing position of a variable was best explained by the difference in independent explanatory power between that variable and the previous one in the nominal ranking of importance. The lesser is this difference, the more likely is the change of position. CONCLUSIONS/SIGNIFICANCE: HP should be applied with caution when more than 9 explanatory variables are used to know ranking of covariate importance. The explained variance is not a useful parameter to use in models with more than 9 independent variables. The inconsistency in the results obtained by HP should be considered in future studies as well as in those

  12. Clustering of local group distances: Publication bias or correlated measurements? II. M31 and beyond

    Energy Technology Data Exchange (ETDEWEB)

    De Grijs, Richard [Kavli Institute for Astronomy and Astrophysics, Peking University, Yi He Yuan Lu 5, Hai Dian District, Beijing 100871 (China); Bono, Giuseppe [Dipartimento di Fisica, Università di Roma Tor Vergata, via Della Ricerca Scientifica 1, I-00133, Roma (Italy)

    2014-07-01

    The accuracy of extragalactic distance measurements ultimately depends on robust, high-precision determinations of the distances to the galaxies in the local volume. Following our detailed study addressing possible publication bias in the published distance determinations to the Large Magellanic Cloud (LMC), here we extend our distance range of interest to include published distance moduli to M31 and M33, as well as to a number of their well-known dwarf galaxy companions. We aim at reaching consensus on the best, most homogeneous, and internally most consistent set of Local Group distance moduli to adopt for future, more general use based on the largest set of distance determinations to individual Local Group galaxies available to date. Based on a careful, statistically weighted combination of the main stellar population tracers (Cepheids, RR Lyrae variables, and the magnitude of the tip of the red-giant branch), we derive a recommended distance modulus to M31 of (m−M){sub 0}{sup M31}=24.46±0.10 mag—adopting as our calibration an LMC distance modulus of (m−M){sub 0}{sup LMC}=18.50 mag—and a fully internally consistent set of benchmark distances to key galaxies in the local volume, enabling us to establish a robust and unbiased, near-field extragalactic distance ladder.

  13. Quantitative evaluation of gender bias in astronomical publications from citation counts

    Science.gov (United States)

    Caplar, Neven; Tacchella, Sandro; Birrer, Simon

    2017-06-01

    Numerous studies across different research fields have shown that both male and female referees consistently give higher scores to work done by men than to identical work done by women 1,2,3 . In addition, women are under-represented in prestigious publications and authorship positions 4,5 and women receive ~10% fewer citations 6,7 . In astronomy, similar biases have been measured in conference participation 8,9 and success rates for telescope proposals 10,11 . Even though the number of doctorate degrees awarded to women is constantly increasing, women still tend to be under-represented in faculty positions 12 . Spurred by these findings, we measure the role of gender in the number of citations that papers receive in astronomy. To account for the fact that the properties of papers written by men and women differ intrinsically, we use a random forest algorithm to control for the non-gender-specific properties of these papers. Here we show that papers authored by women receive 10.4 ± 0.9% fewer citations than would be expected if the papers with the same non-gender-specific properties were written by men.

  14. Clustering of Local Group distances: publication bias or correlated measurements? IV. The Galactic Center

    CERN Document Server

    de Grijs, Richard

    2016-01-01

    Aiming at deriving a statistically well-justified Galactic Center distance, $R_0$, and reducing any occurrence of publication bias, we compiled the most comprehensive and most complete database of Galactic Center distances available to date, containing 273 new or revised $R_0$ estimates published since records began in October 1918 until June 2016. We separate our $R_0$ compilation into direct and indirect distance measurements. The latter include a large body of estimates that rely on centroid determinations for a range of tracer populations as well as measurements based on kinematic observations of objects at the solar circle, combined with a mass and/or rotational model of the Milky Way. Careful assessment of the Galactic Center distances resulting from orbital modeling and statistical parallax measurements in the Galactic nucleus yields our final Galactic Center distance recommendation of $R_0 = 8.3 \\pm 0.2 \\mbox{ (statistical)} \\pm 0.4 \\mbox{ (systematic)}$ kpc. The centroid-based distances are in good a...

  15. Clustering of Local Group distances: publication bias or correlated measurements? II. M31 and beyond

    CERN Document Server

    de Grijs, Richard

    2014-01-01

    The accuracy of extragalactic distance measurements ultimately depends on robust, high-precision determinations of the distances to the galaxies in the local volume. Following our detailed study addressing possible publication bias in the published distance determinations to the Large Magellanic Cloud (LMC), here we extend our distance range of interest to include published distance moduli to M31 and M33, as well as to a number of their well-known dwarf galaxy companions. We aim at reaching consensus on the best, most homogeneous, and internally most consistent set of Local Group distance moduli to adopt for future, more general use based on the largest set of distance determinations to individual Local Group galaxies available to date. Based on a careful, statistically weighted combination of the main stellar population tracers (Cepheids, RR Lyrae variables, and the magnitude of the tip of the red-giant branch), we derive a recommended distance modulus to M31 of $(m-M)_0^{\\rm M31} = 24.46 \\pm 0.10$ mag---ado...

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

    Science.gov (United States)

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

    2015-07-01

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

  17. Harmonic allocation of authorship credit: source-level correction of bibliometric bias assures accurate publication and citation analysis.

    Directory of Open Access Journals (Sweden)

    Nils T Hagen

    Full Text Available Authorship credit for multi-authored scientific publications is routinely allocated either by issuing full publication credit repeatedly to all coauthors, or by dividing one credit equally among all coauthors. The ensuing inflationary and equalizing biases distort derived bibliometric measures of merit by systematically benefiting secondary authors at the expense of primary authors. Here I show how harmonic counting, which allocates credit according to authorship rank and the number of coauthors, provides simultaneous source-level correction for both biases as well as accommodating further decoding of byline information. I also demonstrate large and erratic effects of counting bias on the original h-index, and show how the harmonic version of the h-index provides unbiased bibliometric ranking of scientific merit while retaining the original's essential simplicity, transparency and intended fairness. Harmonic decoding of byline information resolves the conundrum of authorship credit allocation by providing a simple recipe for source-level correction of inflationary and equalizing bias. Harmonic counting could also offer unrivalled accuracy in automated assessments of scientific productivity, impact and achievement.

  18. Estimating the price elasticity of beer: meta-analysis of data with heterogeneity, dependence, and publication bias.

    Science.gov (United States)

    Nelson, Jon P

    2014-01-01

    Precise estimates of price elasticities are important for alcohol tax policy. Using meta-analysis, this paper corrects average beer elasticities for heterogeneity, dependence, and publication selection bias. A sample of 191 estimates is obtained from 114 primary studies. Simple and weighted means are reported. Dependence is addressed by restricting number of estimates per study, author-restricted samples, and author-specific variables. Publication bias is addressed using funnel graph, trim-and-fill, and Egger's intercept model. Heterogeneity and selection bias are examined jointly in meta-regressions containing moderator variables for econometric methodology, primary data, and precision of estimates. Results for fixed- and random-effects regressions are reported. Country-specific effects and sample time periods are unimportant, but several methodology variables help explain the dispersion of estimates. In models that correct for selection bias and heterogeneity, the average beer price elasticity is about -0.20, which is less elastic by 50% compared to values commonly used in alcohol tax policy simulations.

  19. Homocysteine and coronary heart disease: meta-analysis of MTHFR case-control studies, avoiding publication bias.

    Directory of Open Access Journals (Sweden)

    Robert Clarke

    2012-02-01

    Full Text Available BACKGROUND: Moderately elevated blood levels of homocysteine are weakly correlated with coronary heart disease (CHD risk, but causality remains uncertain. When folate levels are low, the TT genotype of the common C677T polymorphism (rs1801133 of the methylene tetrahydrofolate reductase gene (MTHFR appreciably increases homocysteine levels, so "Mendelian randomization" studies using this variant as an instrumental variable could help test causality. METHODS AND FINDINGS: Nineteen unpublished datasets were obtained (total 48,175 CHD cases and 67,961 controls in which multiple genetic variants had been measured, including MTHFR C677T. These datasets did not include measurements of blood homocysteine, but homocysteine levels would be expected to be about 20% higher with TT than with CC genotype in the populations studied. In meta-analyses of these unpublished datasets, the case-control CHD odds ratio (OR and 95% CI comparing TT versus CC homozygotes was 1.02 (0.98-1.07; p = 0.28 overall, and 1.01 (0.95-1.07 in unsupplemented low-folate populations. By contrast, in a slightly updated meta-analysis of the 86 published studies (28,617 CHD cases and 41,857 controls, the OR was 1.15 (1.09-1.21, significantly discrepant (p = 0.001 with the OR in the unpublished datasets. Within the meta-analysis of published studies, the OR was 1.12 (1.04-1.21 in the 14 larger studies (those with variance of log OR<0.05; total 13,119 cases and 1.18 (1.09-1.28 in the 72 smaller ones (total 15,498 cases. CONCLUSIONS: The CI for the overall result from large unpublished datasets shows lifelong moderate homocysteine elevation has little or no effect on CHD. The discrepant overall result from previously published studies reflects publication bias or methodological problems.

  20. Corrigendum to: “Publication bias and time-trend bias in meta-analysis of bicycle helmet efficacy: a re-analysis of Attewell, Glase and McFadden, 2001” [Accid. Anal. Prev. 43 (2011) 1245–1251].

    Science.gov (United States)

    Elvik, Rune

    2013-11-01

    This paper is a corrigendum to the previously published paper: “Publication bias and time-trend bias in meta-analysis of bicycle helmet efficacy: A re-analysis of Attewell, Glase and McFadden, 2001” [Accid. Anal. Prev. (2011) 1245–1251]. This corrigendum was prepared to correct errors in data and analysis in the previously published paper. Like the previously published paper, this paper confirms that the meta-analysis of bicycle helmet efficacy reported by Attewell, Glase and McFadden (Accident Analysis and Prevention, 2001, 345–352) was influenced by publication bias and time-trend bias that was not controlled for. As a result, the analysis reported inflated estimates of the effects of bicycle helmets. This paper presents a re-analysis of the study. The re-analysis included: (1) Ensuring the inclusion of all published studies by means of continuity corrections of estimates of effect relying on zero counts; (2) detecting and adjusting for publication bias by means of the trim-and-fill method; (3) detecting and trying to account for a time-trend bias in estimates of the effects of bicycle helmets; (4) updating the study by including recently published studies evaluating the effects of bicycle helmets. The re-analysis shows smaller safety benefits associated with the use of bicycle helmets than the original study.

  1. Publication bias and the limited strength model of self-control: has the evidence for ego depletion been overestimated?

    Science.gov (United States)

    Carter, Evan C; McCullough, Michael E

    2014-01-01

    Few models of self-control have generated as much scientific interest as has the limited strength model. One of the entailments of this model, the depletion effect, is the expectation that acts of self-control will be less effective when they follow prior acts of self-control. Results from a previous meta-analysis concluded that the depletion effect is robust and medium in magnitude (d = 0.62). However, when we applied methods for estimating and correcting for small-study effects (such as publication bias) to the data from this previous meta-analysis effort, we found very strong signals of publication bias, along with an indication that the depletion effect is actually no different from zero. We conclude that until greater certainty about the size of the depletion effect can be established, circumspection about the existence of this phenomenon is warranted, and that rather than elaborating on the model, research efforts should focus on establishing whether the basic effect exists. We argue that the evidence for the depletion effect is a useful case study for illustrating the dangers of small-study effects as well as some of the possible tools for mitigating their influence in psychological science.

  2. Publication Bias in Reports of Animal Stroke Studies Leads to Major Overstatement of Efficacy

    NARCIS (Netherlands)

    Sena, Emily S.; van der Worp, H. Bart; Bath, Philip M. W.; Howells, David W.; Macleod, Malcolm R.

    2010-01-01

    The consolidation of scientific knowledge proceeds through the interpretation and then distillation of data presented in research reports, first in review articles and then in textbooks and undergraduate courses, until truths become accepted as such both amongst "experts'' and in the public understa

  3. Role of editorial and peer review processes in publication bias: analysis of drug trials submitted to eight medical journals.

    Directory of Open Access Journals (Sweden)

    Marlies van Lent

    Full Text Available Publication bias is generally ascribed to authors and sponsors failing to submit studies with negative results, but may also occur after submission. We evaluated whether submitted manuscripts on randomized controlled trials (RCTs with drugs are more likely to be accepted if they report positive results.Manuscripts submitted from January 2010 through April 2012 to one general medical journal (BMJ and seven specialty journals (Annals of the Rheumatic Diseases, British Journal of Ophthalmology, Gut, Heart, Thorax, Diabetologia, and Journal of Hepatology were included, if at least one study arm assessed the efficacy or safety of a drug and a statistical test was used to evaluate treatment effects. Publication status was retrospectively retrieved from submission systems or provided by journals. Sponsorship and trial results were extracted from manuscripts and classified according to predefined criteria. Main outcome measure was acceptance for publication.Of 15,972 manuscripts submitted, 472 (3.0% were drug RCTs, of which 98 (20.8% were published. Among submitted drug RCTs, 287 (60.8% had positive and 185 (39.2% negative results. Of these, 60 (20.9% and 38 (20.5%, respectively, were published. Manuscripts on non-industry trials (n = 213 reported positive results in 138 (64.8% manuscripts, compared to 71 (47.7% on industry-supported trials (n = 149, and 78 (70.9% on industry-sponsored trials (n = 110. Twenty-seven (12.7% non-industry trials were published, compared to 27 (18.1% industry-supported and 44 (40.0% industry-sponsored trials. After adjustment for other trial characteristics, manuscripts reporting positive results were not more likely to be published (OR, 1.00; 95% CI, 0.61 to 1.66. Submission to specialty journals, sample size, multicentre status, journal impact factor, and corresponding authors from Europe or US were significantly associated with publication.For the selected journals, there was no tendency to preferably publish

  4. Sample-Size Planning for More Accurate Statistical Power: A Method Adjusting Sample Effect Sizes for Publication Bias and Uncertainty.

    Science.gov (United States)

    Anderson, Samantha F; Kelley, Ken; Maxwell, Scott E

    2017-09-01

    The sample size necessary to obtain a desired level of statistical power depends in part on the population value of the effect size, which is, by definition, unknown. A common approach to sample-size planning uses the sample effect size from a prior study as an estimate of the population value of the effect to be detected in the future study. Although this strategy is intuitively appealing, effect-size estimates, taken at face value, are typically not accurate estimates of the population effect size because of publication bias and uncertainty. We show that the use of this approach often results in underpowered studies, sometimes to an alarming degree. We present an alternative approach that adjusts sample effect sizes for bias and uncertainty, and we demonstrate its effectiveness for several experimental designs. Furthermore, we discuss an open-source R package, BUCSS, and user-friendly Web applications that we have made available to researchers so that they can easily implement our suggested methods.

  5. Predictors of Biased Self-perception in Individuals with High Social Anxiety: The Effect of Self-consciousness in the Private and Public Self Domains.

    Science.gov (United States)

    Nordahl, Henrik; Plummer, Alice; Wells, Adrian

    2017-01-01

    "Biased self-perception," the tendency to perceive one's social performance as more negative than observers do, is characteristic of socially anxious individuals. Self-attention processes are hypothesised to underlie biased self-perception, however, different models emphasise different aspects of self-attention, with attention to the public aspects of the self being prominent. The current study aimed to investigate the relative contribution of two types of dispositional self-attention; public- and private self-consciousness to biased self-perception in a high (n = 48) versus a low (n = 48) social anxiety group undergoing an interaction task. The main finding was that private self-consciousness explained substantial and unique variance in biased negative self-perception in individuals with high social anxiety, while public self-consciousness did not. This relationship was independent of increments in state anxiety. Private self-consciousness appeared to have a specific association with bias related to overestimation of negative social performance rather than underestimation of positive social performance. The implication of this finding is that current treatment models of Social anxiety disorder might include broader aspects of self-focused attention, especially in the context of formulating self-evaluation biases.

  6. Predictors of Biased Self-perception in Individuals with High Social Anxiety: The Effect of Self-consciousness in the Private and Public Self Domains

    Directory of Open Access Journals (Sweden)

    Henrik Nordahl

    2017-07-01

    Full Text Available “Biased self-perception,” the tendency to perceive one’s social performance as more negative than observers do, is characteristic of socially anxious individuals. Self-attention processes are hypothesised to underlie biased self-perception, however, different models emphasise different aspects of self-attention, with attention to the public aspects of the self being prominent. The current study aimed to investigate the relative contribution of two types of dispositional self-attention; public- and private self-consciousness to biased self-perception in a high (n = 48 versus a low (n = 48 social anxiety group undergoing an interaction task. The main finding was that private self-consciousness explained substantial and unique variance in biased negative self-perception in individuals with high social anxiety, while public self-consciousness did not. This relationship was independent of increments in state anxiety. Private self-consciousness appeared to have a specific association with bias related to overestimation of negative social performance rather than underestimation of positive social performance. The implication of this finding is that current treatment models of Social anxiety disorder might include broader aspects of self-focused attention, especially in the context of formulating self-evaluation biases.

  7. Quantitative Evaluation of Gender Bias in Astronomical Publications from Citation Counts

    CERN Document Server

    Caplar, Neven; Birrer, Simon

    2016-01-01

    We analyze the role of first (leading) author gender on the number of citations that a paper receives, on the publishing frequency and on the self-citing tendency. We consider a complete sample of over 200,000 publications from 1950 to 2015 from five major astronomy journals. We determine the gender of the first author for over 70% of all publications. The fraction of papers which have a female first author has increased from less than 5% in the 1960s to about 25% today. We find that the increase of the fraction of papers authored by females is slowest in the most prestigious journals such as Science and Nature. Furthermore, female authors write 19$\\pm$7% fewer papers in seven years following their first paper than their male colleagues. At all times papers with male first authors receive more citations than papers with female first authors. This difference has been decreasing with time and amounts to $\\sim$6% measured over the last 30 years. To account for the fact that the properties of female and male firs...

  8. No publication bias in industry funded clinical trials of degenerative diseases of the spine.

    Science.gov (United States)

    Son, Colin; Tavakoli, Samon; Bartanusz, Viktor

    2016-03-01

    Industry sponsorship of clinical research of degenerative diseases of the spine has been associated with excessive positive published results as compared to research carried out without industry funding. We sought the rates of publication of clinical trials of degenerative diseases of the spine based on funding source as a possible explanation for this phenomenon. We reviewed all clinical trials registered at clinicaltrials.gov relating to degenerative diseases of the spine as categorized under six medical subject heading terms (spinal stenosis, spondylolisthesis, spondylolysis, spondylosis, failed back surgery syndrome, intervertebral disc degeneration) and with statuses of completed or terminated. These collected studies were categorized as having, or not having, industry funding. Published results for these studies were then sought within the clinicaltrials.gov database itself, PubMed and Google Scholar. One hundred sixty-one clinical trials met these criteria. One hundred nineteen of these trials had industry funding and 42 did not. Of those with industry funding, 45 (37.8%) had identifiable results. Of those without industry funding, 17 (40.5%) had identifiable results. There was no difference in the rates of publication of results from clinical trials of degenerative diseases of the spine no matter the funding source.

  9. Physics teaching in a public school: an ethnographic case study with an epistemological bias

    Directory of Open Access Journals (Sweden)

    Neusa T. Massoni

    2012-04-01

    Full Text Available This paper is a classroom ethnography. Ethnography in a research strategy that attempts to comprehensively describe a culture, in this case the culture of a physics classroom in the 12th grade of a public high school in Porto Alegre, Brazil. This study is part of a larger scope study designed to investigate the contributions of contemporary views of the nature of science to the improvement of physics teaching. It is in sense that this paper assumes an epistemological perspective. The physics teacher that was observed had conceptions partially aligned to those epistemological views, however, although our initial intention was to search for relationships between her conceptions an her teaching practices we ended up with a detailed interpretative description of the classroom reality that revealed relevant aspects to the comprehension of such a culture and to the teaching and learning process in physics. This interpretative description is what we present here.

  10. The M235T polymorphism in the AGT gene and CHD risk: evidence of a Hardy-Weinberg equilibrium violation and publication bias in a meta-analysis.

    Directory of Open Access Journals (Sweden)

    Mohammad Hadi Zafarmand

    Full Text Available BACKGROUND: The M235T polymorphism in the AGT gene has been related to an increased risk of hypertension. This finding may also suggest an increased risk of coronary heart disease (CHD. METHODOLOGY/PRINCIPAL FINDINGS: A case-cohort study was conducted in 1,732 unrelated middle-age women (210 CHD cases and 1,522 controls from a prospective cohort of 15,236 initially healthy Dutch women. We applied a Cox proportional hazards model to study the association of the polymorphism with acute myocardial infarction (AMI (n = 71 and CHD. In the case-cohort study, no increased risk for CHD was found under the additive genetic model (hazard ratio [HR] = 1.20; 95% confidence interval [CI], 0.86 to 1.68; P = 0.28. This result was not changed by adjustment (HR = 1.17; 95% CI, 0.83 to 1.64; P = 0.38 nor by using dominant, recessive and pairwise genetic models. Analyses for AMI risk under the additive genetic model also did not show any statistically significant association (crude HR = 1.14; 95% CI, 0.93 to 1.39; P = 0.20. To evaluate the association, a comprehensive systematic review and meta-analysis were undertaken of all studies published up to February 2007 (searched through PubMed/MEDLINE, Web of Science and EMBASE. The meta-analysis (38 studies with 13284 cases and 18722 controls showed a per-allele odds ratio (OR of 1.08 (95% CI, 1.01 to 1.15; P = 0.02. Moderate to large levels of heterogeneity were identified between studies. Hardy-Weinberg equilibrium (HWE violation and the mean age of cases were statistically significant sources of the observed variation. In a stratum of non-HWE violation studies, there was no effect. An asymmetric funnel plot, the Egger's test (P = 0.066, and the Begg-Mazumdar test (P = 0.074 were all suggestive of the presence of publication bias. CONCLUSIONS/SIGNIFICANCE: The pooled OR of the present meta-analysis, including our own data, presented evidence that there is an increase in the risk of CHD conferred by the M235T variant

  11. Implementation of a publication strategy in the context of reporting biases. A case study based on new documents from Neurontin® litigation

    Directory of Open Access Journals (Sweden)

    Vedula S

    2012-08-01

    Full Text Available Abstract Background Previous studies have documented strategies to promote off-label use of drugs using journal publications and other means. Few studies have presented internal company communications that discussed financial reasons for manipulating the scholarly record related to off-label indications. The objective of this study was to build on previous studies to illustrate implementation of a publication strategy by the drug manufacturer for four off-label uses of gabapentin (Neurontin®, Pfizer, Inc.: migraine prophylaxis, treatment of bipolar disorders, neuropathic pain, and nociceptive pain. Methods We included in this study internal company documents, email correspondence, memoranda, study protocols and reports that were made publicly available in 2008 as part of litigation brought by consumers and health insurers against Pfizer for fraudulent sales practices in its marketing of gabapentin (see http://pacer.mad.uscourts.gov/dc/cgi-bin/recentops.pl?filename=saris/pdf/ucl%20opinion.pdf for the Court’s findings. We reviewed documents pertaining to 20 clinical trials, 12 of which were published. We categorized our observations related to reporting biases and linked them with topics covered in internal documents, that is, deciding what should and should not be published and how to spin the study findings (re-framing study results to explain away unfavorable findings or to emphasize favorable findings; and where and when findings should be published and by whom. Results We present extracts from internal company marketing assessments recommending that Pfizer and Parke-Davis (Pfizer acquired Parke-Davis in 2000 adopt a publication strategy to conduct trials and disseminate trial findings for unapproved uses rather than an indication strategy to obtain regulatory approval. We show internal company email correspondence and documents revealing how publication content was influenced and spin was applied; how the company selected where trial

  12. Conclusions

    DEFF Research Database (Denmark)

    Franklin, Mark; Nielsen, Julie Hassing

    2016-01-01

    Drawing on the findings of the previous chapters, we assess whether it continues to be helpful for European Parliament (EP) elections to be termed “second order” and/or “second rate”. The 2014 EP elections were indeed still second rate and also predominantly second order. Being “about Europe”, wh...... EP elections is likely to be reflected in later national elections and the circumstances in which those results could lead to substantial policy and/or membership changes in the European Union (EU)....

  13. Conclusion

    OpenAIRE

    Dubasque, François

    2015-01-01

    Lorsque Jean Hennessy entre en politique, rien ne laisse présager un parcours si complexe et déroutant ! Les étapes marquantes d’un itinéraire politique Issu de la grande bourgeoisie négociante, il bénéficie d’un capital d’influence politique, économique et social légué par sa famille. Or, le processus de démocratisation du recrutement du personnel politique dans la première moitié du xxe siècle aboutit à la marginalisation progressive de ceux pour qui le moyen d’accéder aux échelons du pouvo...

  14. Conclusion

    OpenAIRE

    Guibet-Lafaye, Caroline

    2013-01-01

    L’ensemble de ces analyses a permis de montrer que « le bonheur n’est ni une course effrénée au toujours plus et toujours tournée vers l’avenir, ni l’unique nostalgie du passé » (Proust) pas plus qu’il n’est la simple somme des plaisirs de la vie à laquelle seraient soustraits les maux subis. Le bonheur est bien plutôt un état – c’est-à-dire pas seulement un sentiment – de bien-être dépendant d’une pluralité de facteurs. Selon la perspective à partir de laquelle on l’appréhende (la psychologi...

  15. Conclusion

    OpenAIRE

    Le Bart, Christian

    2015-01-01

    Résumons notre démonstration : La découverte des Beatles rend possibles des expériences intimes de plongée en soi. Le passionné a le sentiment de se découvrir au contact de la musique. Cette passion, à ce stade discrète, le singularise par rapport à son environnement immédiat (famille, amis…). On parlera de stratégie de différenciation. Cette stratégie peut conduire au sentiment d’une certaine incompréhension, d’une certaine solitude. La rencontre d’autres passionnés rassure dans un premier t...

  16. Conclusion

    OpenAIRE

    Félix, Joël

    2013-01-01

    La politique économique et financière de L’Averdy s’est fortement inspirée des réflexions de l’administration et des idées des économistes du milieu du xviiie siècle. Sa principale ambition fut d’améliorer les réformes financières de Machault d’Arnouville pour justifier, d’abord, le principe de l’imposition des rentes et doter, ensuite, la monarchie d’une structure d’amortissement de ses dettes pour greffer le financement des dépenses publiques sur la croissance économique. Les contraintes fi...

  17. Conclusion

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    @@ ASEAN has become one of the centers in India's foreign policies, strategic concerns and economic interest, and also an outpost for India to go east to the Asia Pacific Area.19 The first phase of India's "Look East" policy is to fully restore its engagement with ASEAN and concentrate on forging trade and investment ties with the ASEAN countries, this task has already been fulfilled.

  18. Conclusion

    Science.gov (United States)

    Arnold, Steven M.; Wong, Terry T.

    2011-01-01

    This compilation of papers in this book represents approximately half of the works discussed at the MS&T 2010 symposium entitled Tools, Models, Databases, and Simulation Tools Developed and Needed to Realize the Vision of Integrated Computational Materials Engineering at Materials Science & Technology wherein five sessions comprised of 33 presentations was organized. The goal of the symposium was two fold To provide a forum in which current state-of-the-art methods for ICME (e.g., information informatics, experimentation, and modeling) could be openly discussed and critiqued by not only materials scientist but also structural engineers/researchers, component designers, industrial leaders and government program managers. To leave the symposium and in particular the panel discussion with a clear idea of the gaps and barriers (both technical, cultural and economical) that must be addressed in order for ICME to fully succeed. The organizers felt that these goals were met, as particularly evident by the standing room only attendance during a lively panel discussion session at the end of the Symposium. However it is the firm belief of the editors of this book that this symposium was merely a start in the right direction, and that subsequent conferences/symposium (e.g., First World Congress on Integrated Computational Materials Engineering to be held July 10-14, 2011 at Seven Springs Mountain Resort in Pennsylvania) must work hard to ensure that a truly diverse, multidisciplinary, community of researchers and practitioners are present and have ample opportunity for interaction. This will ensure that a proper balance between push and pull disciplines and technologies is maintained so that this emerging focus area, Integrated Computational Materials Engineering (ICME), has the greatest potential for success and impact on "system-level" payoffs. Similarly, a pro-active approach is required to reform historical modes of operation in industry, government and the academic sectors so as to facilitate multidisciplinary collaboration and to clearly articulate the vision and scope of ICME.

  19. Conclusion

    DEFF Research Database (Denmark)

    Jørgensen, Christian Helms; Wallo, Andreas; Toiviainen, Hanna;

    2015-01-01

    production and knowledge-work offer growing learning opportunities to people throughout their active working life. In contrast to the stable and standardised modes of Fordist production, modern working life is characterised by rapid changes and employees interacting across globally distributed professional...... and spatial production networks. Based on continuous relationships of mutual exchange and knowledge building between customers, suppliers and producers, these kinds of learning environments are essentially different from those offered in a school setting. More research is needed to explore the opportunities...

  20. Conclusion

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    @@ One of the major contributions of economic integration to European unification lies in its transformation of traditional European balance concepts and structures. This unification model shows that mere economic and trade ties cannot basically change state relations.

  1. Conclusion

    DEFF Research Database (Denmark)

    Sandøy, Helge; Kristiansen, Tore

    2010-01-01

    1. Comparing empirical findings with the “mountain peak model” In the introduction to this volume, we presented a “mountain peak model” of Nordic purism based on evidence showing that language scholars and lay people are very much in agreement as to where we find the more purist languages and com...

  2. Conclusion

    DEFF Research Database (Denmark)

    Sandøy, Helge; Kristiansen, Tore

    2010-01-01

    1. Comparing empirical findings with the “mountain peak model” In the introduction to this volume, we presented a “mountain peak model” of Nordic purism based on evidence showing that language scholars and lay people are very much in agreement as to where we find the more purist languages...

  3. Conclusion

    Directory of Open Access Journals (Sweden)

    Miquel Strubell

    2004-04-01

    Full Text Available In this brief document, the director of the UOC's Humanities degree, Miquel Strubell, concludes the Dossier focusing on the subject that acted as the catalyst for the 1st Conference on "Humanities Professions in the Knowledge Society", highlighting those areas for debate that, from his point of view, are most interesting and attractive in terms of setting limits and facing up to the problems the degree has at this time of the coming together to form a European university space.

  4. Does Publication Bias Inflate the Apparent Efficacy of Psychological Treatment for Major Depressive Disorder? A Systematic Review and Meta-Analysis of US National Institutes of Health-Funded Trials

    Science.gov (United States)

    Driessen, Ellen; Hollon, Steven D.; Bockting, Claudi L. H.; Cuijpers, Pim; Turner, Erick H.

    2015-01-01

    Background The efficacy of antidepressant medication has been shown empirically to be overestimated due to publication bias, but this has only been inferred statistically with regard to psychological treatment for depression. We assessed directly the extent of study publication bias in trials examining the efficacy of psychological treatment for depression. Methods and Findings We identified US National Institutes of Health grants awarded to fund randomized clinical trials comparing psychological treatment to control conditions or other treatments in patients diagnosed with major depressive disorder for the period 1972–2008, and we determined whether those grants led to publications. For studies that were not published, data were requested from investigators and included in the meta-analyses. Thirteen (23.6%) of the 55 funded grants that began trials did not result in publications, and two others never started. Among comparisons to control conditions, adding unpublished studies (Hedges’ g = 0.20; CI95% -0.11~0.51; k = 6) to published studies (g = 0.52; 0.37~0.68; k = 20) reduced the psychotherapy effect size point estimate (g = 0.39; 0.08~0.70) by 25%. Moreover, these findings may overestimate the "true" effect of psychological treatment for depression as outcome reporting bias could not be examined quantitatively. Conclusion The efficacy of psychological interventions for depression has been overestimated in the published literature, just as it has been for pharmacotherapy. Both are efficacious but not to the extent that the published literature would suggest. Funding agencies and journals should archive both original protocols and raw data from treatment trials to allow the detection and correction of outcome reporting bias. Clinicians, guidelines developers, and decision makers should be aware that the published literature overestimates the effects of the predominant treatments for depression. PMID:26422604

  5. There may not be a cultural life script for public events, but there is a youth bias: Response to Janssen (2014)

    DEFF Research Database (Denmark)

    Koppel, Jonathan Mark; Berntsen, Dorthe

    2015-01-01

    Janssen asserts that, in a recent paper, we introduced the concept of a cultural life script for public events, in the form of the youth bias. Moreover, he contends that we claimed to have found evidence for such a life script. Correspondingly, he frames his own failure to find evidence for a lif...

  6. Evaluating Public Health Interventions: 3. The Two-Stage Design for Confounding Bias Reduction-Having Your Cake and Eating It Two.

    Science.gov (United States)

    Spiegelman, Donna; Rivera-Rodriguez, Claudia L; Haneuse, Sebastien

    2016-07-01

    In public health evaluations, confounding bias in the estimate of the intervention effect will typically threaten the validity of the findings. It is a common misperception that the only way to avoid this bias is to measure detailed, high-quality data on potential confounders for every intervention participant, but this strategy for adjusting for confounding bias is often infeasible. Rather than ignoring confounding altogether, the two-phase design and analysis-in which detailed high-quality confounding data are obtained among a small subsample-can be considered. We describe the two-stage design and analysis approach, and illustrate its use in the evaluation of an intervention conducted in Dar es Salaam, Tanzania, of an enhanced community health worker program to improve antenatal care uptake.

  7. The Regressive Research of Bias Least Square Method of Public Financial Capability of China%我国财政能力的偏最小二乘回归研究

    Institute of Scientific and Technical Information of China (English)

    周子康; 崔斌

    2003-01-01

    Based on the adjustment of public financial revenue and expenditure of China according to the international comparable scope, the authors project and research the condition of public financial revenue and expenditure in China by using bias least square method. After the analysis, the authors think that the real public financial capability of China is not as weak as people estimate in advance.

  8. Media Bias

    OpenAIRE

    Sendhil Mullainathan; Andrei Shleifer

    2002-01-01

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

  9. [SENTIERI Project: discussion and conclusions].

    Science.gov (United States)

    Pirastu, Roberta; Ricci, Paolo; Comba, Pietro; Bianchi, Fabrizio; Biggeri, Annibale; Conti, Susanna; Fazzo, Lucia; Forastiere, Francesco; Iavarone, Ivano; Martuzzi, Marco; Musmeci, Loredana; Pasetto, Roberto; Zona, Amerigo; Crocetti, Emanuele

    2014-01-01

    The SENTIERI Project represents the first comprehensive analysis of the health impact of residence in National Priority Contaminated Sites (NPCSs). For the first time, it considers three distinct health outcomes: mortality (2003-2010), cancer incidence (1996- 2005) and hospital discharges (2005-2010). The Report includes a commentary explaining methodology and approach, as well as remarks on the causal association between environmental exposures and investigated health outcomes based on the a priori assessments of the epidemiological evidence; the main implications for public health and scientific research priorities are also presented. The approach put forward by SENTIERI was among those sanctioned by the World Health Organization to conduct an initial description of the health status of residents of contaminated sites. Results relating to individual diseases that can be traced back to a single agent, such as asbestiform fibres, can be easily analysed. The Biancavilla NPCS (where the fluoro-edenite asbestiform fibre was found) displays excesses of pleural mesothelioma and its proxy, malignant pleural tumours, as does Priolo, where asbestos coexists with other pollutants. Increased risk was also recorded in NPCSs adjacent to the coast hosting harbour areas (such as Trieste, Taranto and Venice) or comprising industrial areas specialising in the production of chemicals (Laguna di Grado e Marano, Priolo and Venezia) and steel (Taranto, Terni, Trieste). Increases of pathologies, such as cancer and respiratory diseases, connected to more than one agent, in industrial sites with multiple and diverse sources of exposures, prove harder to interpret. There are also more complex cases in which results do not appear consistent in the three databases or by gender (such as lung cancer in Venice, where mortality and hospital discharges have only increased among women). In order to adequately examine these we must consider factors such as the appropriateness of the health outcome

  10. Misunderstanding publication bias: editors are not blameless after all [v1; ref status: indexed, http://f1000r.es/YvAwwD

    Directory of Open Access Journals (Sweden)

    Stephen Senn

    2012-12-01

    Full Text Available In analysing whether there is an editorial bias in favour of positive studies, researchers have made implicit assumptions that are implausible. In particular, to justify the conclusion that there is no bias because observed editorial acceptance rates do not favour positive studies, the assumption that the decision to submit an article is based solely on quality would be required. If, on the other hand, submission were based on perceived probability of acceptance, negative and positive studies would not differ in terms of acceptance rates, but in terms of quality. It is shown, using a simple graphical model, how similar underlying situations as regards the relationship between quality and probability of acceptance on the one hand and study outcome (positive or negative and probability of acceptance on the other could produce dramatically different results depending on the behaviour of authors. Furthermore, there is, in fact, some evidence that submitted negative studies are, on average, of higher quality than positive ones. This calls into question the standard interpretation of the studies examining editorial bias. It would appear that despite similar probabilities of acceptance for negative and positive studies, editors could be discriminating against negative studies.

  11. One metric does not tell the whole story of scientific production. III. Management and conclusions

    Directory of Open Access Journals (Sweden)

    Nieves GONZÁLEZ-FERNÁNDEZ-VILLAVICENCIO

    2016-09-01

    Full Text Available Introduction: There are different strategies for scientific publication that can be addressed from the perspective of management, ahead of the assessment by national agencies. Rising of alternative metrics, services and suppliers. Method: Narrative review. Results: the characteristic features of the evaluation criteria of scientific publications by Spanish agencies evaluation are presented and described altmetrics services. Conclusions: The need for national evaluation systems of scientific production to avoid the current bias and ignorance of the publishing sector which suffer WoS and Scopus arises. And also the need for other altmetric systems, complementary to traditional, to expand the type of scientific products and evaluate the scientific social impact.

  12. Intergroup bias.

    Science.gov (United States)

    Hewstone, Miles; Rubin, Mark; Willis, Hazel

    2002-01-01

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

  13. Bias neglect: a blind spot in the evaluation of scientific results.

    Science.gov (United States)

    Strickland, Brent; Mercier, Hugo

    2014-01-01

    Experimenter bias occurs when scientists' hypotheses influence their results, even if involuntarily. Meta-analyses have suggested that in some domains, such as psychology, up to a third of the studies could be unreliable due to such biases. A series of experiments demonstrates that while people are aware of the possibility that scientists can be more biased when the conclusions of their experiments fit their initial hypotheses, they robustly fail to appreciate that they should also be more sceptical of such results. This is true even when participants read descriptions of studies that have been shown to be biased. Moreover, participants take other sources of bias-such as financial incentives-into account, showing that this bias neglect may be specific to theory-driven hypothesis testing. In combination with a common style of scientific reporting, bias neglect could lead the public to accept premature conclusions.

  14. Racial bias in federal nutrition policy, Part I: The public health implications of variations in lactase persistence.

    Science.gov (United States)

    Bertron, P; Barnard, N D; Mills, M

    1999-03-01

    The Dietary Guidelines for Americans from the basis for all federal nutrition programs and incorporate the Food Guide Pyramid, a tool to educate consumers on putting the Guidelines into practice. The Pyramid recommends two to three daily servings of dairy products. However, research has shown that lactase nonpersistence, the loss of enzymes that digest the milk sugar lactose, occurs in a majority of African-, Asian-, Hispanic-, and Native-American individuals. Whites are less likely to develop lactase nonpersistence and less likely to have symptoms when it does occur. Calcium is available in other foods that do not contain lactose. Osteoporosis is less common among African Americans and Mexican Americans than among whites, and there is little evidence that dairy products have an effect on osteoporosis among racial minorities. Evidence suggests that a modification of federal nutrition policies, making dairy-product use optional in light of other calcium sources, may be a helpful public health measure.

  15. Implementation of a publication strategy in the context of reporting biases. A case study based on new documents from Neurontin litigation.

    Science.gov (United States)

    Vedula, S Swaroop; Goldman, Palko S; Rona, Ilyas J; Greene, Thomas M; Dickersin, Kay

    2012-08-13

    Previous studies have documented strategies to promote off-label use of drugs using journal publications and other means. Few studies have presented internal company communications that discussed financial reasons for manipulating the scholarly record related to off-label indications. The objective of this study was to build on previous studies to illustrate implementation of a publication strategy by the drug manufacturer for four off-label uses of gabapentin (Neurontin, Pfizer, Inc.): migraine prophylaxis, treatment of bipolar disorders, neuropathic pain, and nociceptive pain. We included in this study internal company documents, email correspondence, memoranda, study protocols and reports that were made publicly available in 2008 as part of litigation brought by consumers and health insurers against Pfizer for fraudulent sales practices in its marketing of gabapentin (see http://pacer.mad.uscourts.gov/dc/cgi-bin/recentops.pl?filename=saris/pdf/ucl%20opinion.pdf for the Court's findings).We reviewed documents pertaining to 20 clinical trials, 12 of which were published. We categorized our observations related to reporting biases and linked them with topics covered in internal documents, that is, deciding what should and should not be published and how to spin the study findings (re-framing study results to explain away unfavorable findings or to emphasize favorable findings); and where and when findings should be published and by whom. We present extracts from internal company marketing assessments recommending that Pfizer and Parke-Davis (Pfizer acquired Parke-Davis in 2000) adopt a publication strategy to conduct trials and disseminate trial findings for unapproved uses rather than an indication strategy to obtain regulatory approval. We show internal company email correspondence and documents revealing how publication content was influenced and spin was applied; how the company selected where trial findings would be presented or published; how publication of

  16. Bias During the Evaluation of Animal Studies?

    OpenAIRE

    Andrew Knight

    2012-01-01

    Simple Summary Animal experimentation evokes strong emotional responses in people on both sides of the debate surrounding its ethical status. However, the true level of its usefulness to society may only be discerned by careful examination of reliable scientific evidence. My recent book, The Costs and Benefits of Animal Experiments, reviewed more than 500 relevant scientific publications. Recently in this journal, however, a reviewer essentially accused me of bias. Yet the conclusions of my b...

  17. Collaborative Automation Reliably Remediating Erroneous Conclusion Threats (CARRECT)

    Science.gov (United States)

    Lansey, Jonathan C.; Picciano, Paul; Yohai, Ian; Grant, Fred; Gern, Robert

    2013-01-01

    Objective The objective of the CARRECT software is to make cutting edge statistical methods for reducing bias in epidemiological studies easy to use and useful for both novice and expert users. Introduction Analyses produced by epidemiologists and public health practitioners are susceptible to bias from a number of sources including missing data, confounding variables, and statistical model selection. It often requires a great deal of expertise to understand and apply the multitude of tests, corrections, and selection rules, and these tasks can be time-consuming and burdensome. To address this challenge, Aptima began development of CARRECT, the Collaborative Automation Reliably Remediating Erroneous Conclusion Threats system. When complete, CARRECT will provide an expert system that can be embedded in an analyst’s workflow. CARRECT will support statistical bias reduction and improved analyses and decision making by engaging the user in a collaborative process in which the technology is transparent to the analyst. Methods Older approaches to imputing missing data, including mean imputation and single imputation regression methods, have steadily given way to a class of methods known as “multiple imputation” (hereafter “MI”; Rubin 1987). Rather than making the restrictive assumption that the data are missing completely at random (MCAR), MI typically assumes the data are missing at random (MAR). There are two key innovations behind MI. First, the observed values can be useful in predicting the missing cells, and thus specifying a joint distribution of the data is the first step in implementing the models. Second, single imputation methods will likely fail not only because of the inherent uncertainty in the missing values but also because of the estimation uncertainty associated with generating the parameters in the imputation procedure itself. By contrast, drawing the missing values multiple times, thereby generating m complete datasets along with the

  18. Application and investigation of a bound for outcome reporting bias

    Directory of Open Access Journals (Sweden)

    Gamble Carrol

    2007-03-01

    Full Text Available Abstract Background Direct empirical evidence for the existence of outcome reporting bias is accumulating and this source of bias is recognised as a potential threat to the validity of meta-analysis of randomised clinical trials. Methods A method for calculating the maximum bias in a meta-analysis due to publication bias is adapted for the setting where within-study selective non-reporting of outcomes is suspected, and compared to the alternative approach of missing data imputation. The properties of both methods are investigated in realistic small sample situations. Results The results suggest that the adapted Copas and Jackson approach is the preferred method for reviewers to apply as an initial assessment of robustness to within-study selective non-reporting. Conclusion The Copas and Jackson approach is a useful method for systematic reviewers to apply to assess robustness to outcome reporting bias.

  19. Searching ClinicalTrials.gov did not change the conclusions of a systematic review.

    Science.gov (United States)

    Wilson, Lisa M; Sharma, Ritu; Dy, Sydney M; Waldfogel, Julie M; Robinson, Karen A

    2017-07-27

    We assessed the effect of searching ClinicalTrials.gov on the conclusions of a systematic review. We conducted this case study concurrently with a systematic review. We searched ClinicalTrials.gov on March 9, 2016, to identify trial records eligible for inclusion in the review. Two independent reviewers screened ClinicalTrials.gov records. We compared conclusions and strength of evidence grade with and without ClinicalTrials.gov records for 31 comparisons and 2 outcomes. We identified 106 trials (53 in the peer-reviewed literature only, 23 in ClinicalTrials.gov only, and 30 in both sources). For one comparison, the addition of results identified through ClinicalTrials.gov reduced the pooled effect size. We found evidence of selective outcome reporting for two comparisons and suspected publication bias for another two comparisons. For all other comparisons, searching ClinicalTrials.gov did not change conclusions or the strength of evidence grading for the two outcomes. Our search of ClinicalTrials.gov bolstered suspicions of reporting biases but did not change either the conclusions or the strength of evidence grading. Further research is needed to determine the effect of searching ClinicalTrials.gov on the conclusions of systematic reviews in different topic areas and as the new rules for registration of trial results take effect. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Using IRT Approach to Detect Gender Biased Items in Public Examinations: A Case Study from the Botswana Junior Certificate Examination in Mathematics

    Science.gov (United States)

    Adedoyin, O. O.

    2010-01-01

    This is a quantitative study, which attempted to detect gender bias test items from the Botswana Junior Certificate Examination in mathematics. To detect gender bias test items, a randomly selected sample of 4000 students responses to mathematics paper 1 of the Botswana Junior Certificate examination were selected from 36,000 students who sat for…

  1. Does Publication Bias Inflate the Apparent Efficacy of Psychological Treatment for Major Depressive Disorder? A Systematic Review and Meta-Analysis of US National Institutes of Health-Funded Trials.

    Directory of Open Access Journals (Sweden)

    Ellen Driessen

    Full Text Available The efficacy of antidepressant medication has been shown empirically to be overestimated due to publication bias, but this has only been inferred statistically with regard to psychological treatment for depression. We assessed directly the extent of study publication bias in trials examining the efficacy of psychological treatment for depression.We identified US National Institutes of Health grants awarded to fund randomized clinical trials comparing psychological treatment to control conditions or other treatments in patients diagnosed with major depressive disorder for the period 1972-2008, and we determined whether those grants led to publications. For studies that were not published, data were requested from investigators and included in the meta-analyses. Thirteen (23.6% of the 55 funded grants that began trials did not result in publications, and two others never started. Among comparisons to control conditions, adding unpublished studies (Hedges' g = 0.20; CI95% -0.11~0.51; k = 6 to published studies (g = 0.52; 0.37~0.68; k = 20 reduced the psychotherapy effect size point estimate (g = 0.39; 0.08~0.70 by 25%. Moreover, these findings may overestimate the "true" effect of psychological treatment for depression as outcome reporting bias could not be examined quantitatively.The efficacy of psychological interventions for depression has been overestimated in the published literature, just as it has been for pharmacotherapy. Both are efficacious but not to the extent that the published literature would suggest. Funding agencies and journals should archive both original protocols and raw data from treatment trials to allow the detection and correction of outcome reporting bias. Clinicians, guidelines developers, and decision makers should be aware that the published literature overestimates the effects of the predominant treatments for depression.

  2. 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...

  3. Associated Factors and Consequences of Risk of Bias in Randomized Controlled Trials of Yoga: A Systematic Review.

    Directory of Open Access Journals (Sweden)

    Holger Cramer

    Full Text Available Bias in randomized controlled trials (RCTs of complementary therapy interventions seems to be associated with specific factors and to potentially distort the studies' conclusions. This systematic review assessed associated factors of risk of bias and consequences for the studies' conclusions in RCTs of yoga as one of the most commonly used complementary therapies.Medline/PubMed, Scopus, IndMED and the Cochrane Library were searched through February 2014 for yoga RCTs. Risk of selection bias was assessed using the Cochrane tool and regressed to a publication year; b country of origin; c journal type; and d impact factor using multiple logistic regression analysis. Likewise, the authors' conclusions were regressed to risk of bias.A total of 312 RCTs were included. Impact factor ranged from 0.0 to 39.2 (median = 1.3; 60 RCT (19.2% had a low risk of selection bias, and 252 (80.8% had a high or unclear risk of selection bias. Only publication year and impact factor significantly predicted low risk of bias; RCTs published after 2001 (adjusted odds ratio (OR = 12.6; 95% confidence interval (CI = 1.7, 94.0; p<0.001 and those published in journals with impact factor (adjusted OR = 2.6; 95%CI = 1.4, 4.9; p = 0.004 were more likely to have low risk of bias. The authors' conclusions were not associated with risk of bias.Risk of selection bias was generally high in RCTs of yoga; although the situation has improved since the publication of the revised CONSORT statement 2001. Pre-CONSORT RCTs and those published in journals without impact factor should be handled with increased care; although risk of bias is unlikely to distort the RCTs' conclusions.

  4. Bias-Based Harassment in New York City Public Schools: A Report Card on the Department of Education's Implementation of Chancellor's Regulation A-832

    Science.gov (United States)

    Asian American Legal Defense and Education Fund, 2009

    2009-01-01

    On September 3, 2008, Mayor Michael Bloomberg and Schools Chancellor Joel Klein announced Chancellor's Regulation A-832, which established a procedure for addressing student-to-student bias-based harassment, intimidation, and bullying. Community groups and advocates stood with the Mayor and Department of Education (DOE) leadership in announcing…

  5. Only one simple conclusion about the climate

    Energy Technology Data Exchange (ETDEWEB)

    Jaremko, G.

    2000-07-24

    Findings concerning climate change, by a three-man team of scientists from the North Dakota Geological Survey, which were presented in a paper read at the Eight International Williston Basin Horizontal Well Workshop, are discussed. The survey by the three scientists covered more than 6,000 scholarly publications. It reported that while the rise in the Earth's temperature is beyond argument, there is anything but agreement as to the causes, or whether the trend is unusual enough to justify concerted and costly actions to change lifestyles. It is shown by direct instrumental measurements that the average temperature at the Earth's surface increased about 0.8 degree Celsius between 1866 and 1998. During that time the concentration of carbon dioxide in the atmosphere increased from 280 to 353 parts per million. While it is generally assumed that the global warming was caused by human activities, new techniques of measurement such as glacier ice coring, dendrochronology (tree-growth rings), lichenometry (measuring the diameter of lichens) and counting concentrations of oxygen 18 and 16 (isotopes whose presence in marine fossils varies depending on temperature) suggest that most of the global warming took place before the increase in carbon dioxide concentration occurred, raising the possibility that the increase in average temperature had causes other than the increase in greenhouse gases. Some of the studies reviewed by the group show that in Europe between ice ages during the Eemian period, some 135,000 to 110,000 years ago, temperature variations of seven degrees Celsius took place; they dropped from two degree Celsius warmer than today to five degree Celsius colder than today. Based on these findings the group's only firm conclusion was that climate is in a continual flux.

  6. Bias During the Evaluation of Animal Studies?

    Science.gov (United States)

    Knight, Andrew

    2012-01-01

    Simple Summary Animal experimentation evokes strong emotional responses in people on both sides of the debate surrounding its ethical status. However, the true level of its usefulness to society may only be discerned by careful examination of reliable scientific evidence. My recent book, The Costs and Benefits of Animal Experiments, reviewed more than 500 relevant scientific publications. Recently in this journal, however, a reviewer essentially accused me of bias. Yet the conclusions of my book are based on sound reasoning and strong evidence, and no critic has yet provided any substantive evidence to refute them. Abstract 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. PMID:26486779

  7. Conclusiones y recomendaciones Conclusions and recommendations

    Directory of Open Access Journals (Sweden)

    María Saquero Martínez

    2006-12-01

    following technical conclusions and recommendations.This document, which is intended to be practical and operational, has been reviewed and agreed by all speakers and by the Scientific Committee of the Conference, and is written in the key of pending tasks to be addressed by both public authorities and companies in the sector and holders hazard installations.

  8. 农村公众风险认知偏差的非正式制度因素研究%Informal Institutional Factors of Rural Public risk Perception Bias

    Institute of Scientific and Technical Information of China (English)

    龙云; 李彬

    2015-01-01

    In the sudden rural public events, the public risk perception bias is an important factor to the public psychological panic. so the research of public risk perception bias and its influence factors is an important part of the research work. On the basis of defining the deviation of the rural emergency and public risk, the influence mechanism of the traditional culture and customs of rural society is analyzed, and the relevant countermeasures are put forward to improve the education level of rural residents, to promote the effective transfer of rural information, and to strengthen the communication between government and people.%农村突发事件中公众风险认知偏差是公众心理恐慌产生的重要影响因素,因此公众风险认知偏差及其影响因子的研究是突发事件管控研究工作中的重要一环。在界定农村突发事件和公众风险认知偏差的基础上,分析农村社会的传统文化习惯习俗等非正式制度对公众风险认知偏差的影响机理,提出相关对策如下:提高农村居民的教育水平;促进农村信息的有效传递;加强政府与民众之间的沟通。

  9. Grinding the Antitesting Ax: More Bias than Evidence behind NRC Panel's Conclusions

    Science.gov (United States)

    Hanushek, Eric A.

    2012-01-01

    In all the acrimonious discussion surrounding No Child Left Behind Act of 2001 (NCLB), surprisingly little attention has been given to the actual impact of that legislation and other accountability systems on student performance. Now a reputable body, a committee set up by the National Research Council (NRC), the research arm of the National…

  10. Chikungunya in the Americas: Recommendations and Conclusions.

    Science.gov (United States)

    Graham, Barney S; Repik, Patricia M; Yactayo, Sergio

    2016-12-15

    Discovered in 1953, chikungunya virus (CHIKV) circulated in Africa and Southeast Asia, with periodic outbreaks, for many years. Highly efficient transmission following a genetic mutation of the virus in 2005 caused its global spread. Associated with significant morbidity, CHIKV creates a large public health burden, and despite various efforts, there are currently no licensed vaccines nor specific treatments. To garner a better understanding of the virus, identify gaps in knowledge, and guide the development of more-effective interventions, the World Health Organization and National Institute of Allergy and Infectious Diseases assembled global experts for discussion and review. Herein described are the outcomes. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  11. Reporting bias in medical research - a narrative review

    Directory of Open Access Journals (Sweden)

    Kölsch Heike

    2010-04-01

    overestimation of efficacy and the underestimation of safety risks of interventions. In conclusion, reporting bias is a widespread phenomenon in the medical literature. Mandatory prospective registration of trials and public access to study data via results databases need to be introduced on a worldwide scale. This will allow for an independent review of research data, help fulfil ethical obligations towards patients, and ensure a basis for fully-informed decision making in the health care system.

  12. Results and conclusion; Resultados e conclusoes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-10-15

    This chapter shows the results and conclusions of the ordered studies by the Science and Technology Ministry from Brazil to the Center of Management and Strategic Studies (CGEE), executed by a multidisciplinary team, most of UNICAMP - State University of Campinas, SP - for evaluation of Brazilian capacity and potential in the production of fuel bioethanol.

  13. Phototropin-dependent biased relocalization of cp-actin filaments can be induced even when chloroplast movement is inhibited

    OpenAIRE

    Yamada, Noboru; Suetsugu, Noriyuki; Wada, Masamitsu; Kadota, Akeo

    2011-01-01

    In a recent publication using an actin-visualized line of Arabidopsis (Ichikawa et al. 2011, ref. 11), we reported a detailed analysis with higher time resolution on the dynamics of chloroplast actin filaments (cp-actin filaments) during chloroplast avoidance movement and demonstrated a good correlation between the biased configuration of cp-actin filaments and chloroplast movement. However, we could not conclusively determine whether the reorganization of cp-actin filaments into a biased con...

  14. Industry and water security: overarching conclusions.

    Science.gov (United States)

    Stigson, B

    2001-01-01

    Fresh water is key to sustainable development. World Business Council for Sustainable Development members are addressing fresh water use "within the corporate fenceline". However, to address water issues "outside the corporate fenceline" will require creative new public-private partnerships. Government's role is to provide sound framework conditions that will encourage businesses to invest time, staff and resources to address vital fresh water issues. Industry is committed to best practice within its internal operations and is ready to enter into partnerships to address broader fresh water issues.

  15. Power and Democracy in Denmark. Conclusions

    DEFF Research Database (Denmark)

    Andersen, Jørgen Goul; Christiansen, Peter Munk; Beck Jørgensen, Torben

    . The mass media have become a controlling element in political communication; many politicians feel compelled to act on single issues and make knee-jerk political decisions. Other decisions carry the mark of opaque influence by strong private interests. Finally, the transfer of competences to the EU has......, and the political institutions show considerable democratic robustness. However, not everything has gone or is going well. There are still pronounced social divisions in Danish society, although their nature has changed somewhat. The ideal of an informed public debate does not always enjoy the best conditions...

  16. Misrepresentation of neuroscience data might give rise to misleading conclusions in the media: the case of attention deficit hyperactivity disorder.

    Directory of Open Access Journals (Sweden)

    Francois Gonon

    Full Text Available BACKGROUND: There is often a huge gap between neurobiological facts and firm conclusions stated by the media. Data misrepresentation in the conclusions and summaries of neuroscience articles might contribute to this gap. METHODOLOGY/PRINCIPAL FINDINGS: Using the case of attention deficit hyperactivity disorder (ADHD, we identified three types of misrepresentation. The first relies on prominent inconsistencies between results and claimed conclusions and was observed in two scientific reports dealing with ADHD. Only one out of the 61 media articles echoing both scientific reports adequately described the results and, thus questioned the claimed conclusion. The second type of misrepresentation consists in putting a firm conclusion in the summary while raw data that strongly limit the claim are only given in the results section. To quantify this misrepresentation we analyzed the summaries of all articles asserting that polymorphisms of the gene coding for the D4 dopaminergic receptor are associated with ADHD. Only 25 summaries out of 159 also mentioned that this association confers a small risk. This misrepresentation is also observed in most media articles reporting on ADHD and the D4 gene. The third misrepresentation consists in extrapolating basic and pre-clinical findings to new therapeutic prospects in inappropriate ways. Indeed, analysis of all ADHD-related studies in mice showed that 23% of the conclusions were overstated. The frequency of this overstatement was positively related with the impact factor of the journal. CONCLUSION/SIGNIFICANCE: Data misrepresentations are frequent in the scientific literature dealing with ADHD and may contribute to the appearance of misleading conclusions in the media. In synergy with citation distortions and publication biases they influence social representations and bias the scientific evidence in favor of the view that ADHD is primarily caused by biological factors. We discuss the social consequences and

  17. Millian superiorities and the repugnant conclusion

    DEFF Research Database (Denmark)

    Jensen, Karsten Klint

    2008-01-01

    James Griffin has considered a form of superiority in value that is weaker than lexical priority as a possible remedy to the Repugnant Conclusion. In this article, I demonstrate that, in a context where value is additive, this weaker form collapses into the stronger form of superiority. And in a ......James Griffin has considered a form of superiority in value that is weaker than lexical priority as a possible remedy to the Repugnant Conclusion. In this article, I demonstrate that, in a context where value is additive, this weaker form collapses into the stronger form of superiority...... of these results for different interpretations of Griffin's suggestion regarding population ethics. None of them comes out very successful, but perhaps they nevertheless retain some interest....

  18. Power and Democracy in Denmark. Conclusions

    DEFF Research Database (Denmark)

    Andersen, Jørgen Goul; Christiansen, Peter Munk; Beck Jørgensen, Torben

    In 1997, the Danish Parliament decided to launch a power study, officially An Analysis of Democracy and Power in Denmark. A steering committee consisting of five independent researchers was assigned responsibility for the project. The Steering Committee has gathered the overall conclusions from...... the numerous projects under the Power Study, and this book is a short presentation of these conclusions.The main focus of the book is the state of democracy in Denmark at the dawn of the 21st century. How has democracy fared, has the development made things better or worse, and to which extent does...... contemporary democracy live up to our democratic ideals? The answer is that in many ways democracy is doing better than we might have expected, considering the intense pressure on the nation state and the democratic institutions in the postwar period. The Danish population is still full of democratic life...

  19. Racially Biased Policing: Determinants of Citizen Perceptions

    Science.gov (United States)

    Weitzer, Ronald; Tuch, Steven A.

    2005-01-01

    The current controversy surrounding racial profiling in America has focused renewed attention on the larger issue of racial bias by the police. Yet little is known about the extent of police racial bias and even less about public perceptions of the problem. This article analyzes recent national survey data on citizens' views of and reported…

  20. 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.

  1. Superiority in value and the repugnant conclusion

    DEFF Research Database (Denmark)

    Jensen, Karsten Klint

    2007-01-01

    James Griffin has considered a weak form of superiority in value a possible remedy to the Repugnant Conclusion. In this paper, I demonstrate that, in a context where value is additive, this weaker form collapses into a stronger form of superiority. And in a context where value is non-additive, weak...... superiority does not amount to a radical value difference at all. I then spell out the consequences of these results for different interpretations of Griffin's suggestion regarding population ethics. None of them comes out very successful, but perhaps they nevertheless retain some interest....

  2. Misrepresentation of neuroscience data might give rise to misleading conclusions in the media: the case of attention deficit hyperactivity disorder.

    Science.gov (United States)

    Gonon, Francois; Bezard, Erwan; Boraud, Thomas

    2011-01-31

    There is often a huge gap between neurobiological facts and firm conclusions stated by the media. Data misrepresentation in the conclusions and summaries of neuroscience articles might contribute to this gap. Using the case of attention deficit hyperactivity disorder (ADHD), we identified three types of misrepresentation. The first relies on prominent inconsistencies between results and claimed conclusions and was observed in two scientific reports dealing with ADHD. Only one out of the 61 media articles echoing both scientific reports adequately described the results and, thus questioned the claimed conclusion. The second type of misrepresentation consists in putting a firm conclusion in the summary while raw data that strongly limit the claim are only given in the results section. To quantify this misrepresentation we analyzed the summaries of all articles asserting that polymorphisms of the gene coding for the D4 dopaminergic receptor are associated with ADHD. Only 25 summaries out of 159 also mentioned that this association confers a small risk. This misrepresentation is also observed in most media articles reporting on ADHD and the D4 gene. The third misrepresentation consists in extrapolating basic and pre-clinical findings to new therapeutic prospects in inappropriate ways. Indeed, analysis of all ADHD-related studies in mice showed that 23% of the conclusions were overstated. The frequency of this overstatement was positively related with the impact factor of the journal. Data misrepresentations are frequent in the scientific literature dealing with ADHD and may contribute to the appearance of misleading conclusions in the media. In synergy with citation distortions and publication biases they influence social representations and bias the scientific evidence in favor of the view that ADHD is primarily caused by biological factors. We discuss the social consequences and the causes of data misrepresentations and suggest a few corrective actions.

  3. Epistemology applied to conclusions of expert reports.

    Science.gov (United States)

    Lucena-Molina, Jose-Juan

    2016-07-01

    It is believed that to build a robust reasoning logic to make probabilistic inferences in forensic science from a merely mathematical or logistical viewpoint is not enough. Mathematical logic is the positive science of reasoning and as for that it is only interested in the positive calculus of its validity, regardless any prior ontological assumption. But without a determined ontology and epistemology which imply to define the concepts that they will use, it seems difficult that the proposed scientifically correct mathematical solution be successful as a European standard for making conclusions in forensic reports because it has to be based on judicial language. Forensic experts and Courts are not interested in the development of a positive science but in a practical science: in clarifying whether certain known facts are related to a possible crime. Therefore, not only the coherence of the demonstrative logic reasoning used (logic of propositions) is important, but also the precision of the concepts used by language and consistency among them in reasoning (logic of concepts). There is a linguistic level essential for a successful communication between the forensic practitioner and the Court which is mainly related, in our opinion, to semantics and figures of speech. The first one is involved because words used in forensic conclusions often have different meanings - it is said that they are polysemic - and the second one because there is often metonymy as well. Besides, semantic differences among languages regarding words with the same etymological root add another difficulty for a better mutual understanding. The two main European judicial systems inherit a wide and deep culture related to evidence in criminal proceedings and each of them has coined their own terminology but there are other two more abstract levels such as logical and epistemological, where we can find solid arguments by which terms used at legal level on conclusions of forensic reports could be

  4. The Financial Crisis: Origins, Causes And Conclusions

    Directory of Open Access Journals (Sweden)

    Eneida Permeti

    2015-03-01

    Full Text Available The crisis in recent years took start in response to a crisis of the real estate market in the United States in 2007. The year 2009 has seen an economic crisis and between 2010 and 2011 it was known the spreading of the crisis sovereign debt and public finances of many countries. The financial markets failed in their main task: the allocation of risk. The products and services traded in the financial market are characterized by the immateriality and legal complexity. It means a high uncertainty degree and a high risk. Therefore is very important to protect the investors and this means: give them the right information, right legislation, market confidence and a product that respond to their needs. The crisis causes are: weaknesses in the regulatory, malfunction of the rating agencies, political errors and conflicts of interest. This means that we need: more rules, more capital, less debt, more transparency. The financial markets and the economy have always moved in harmony and savers have undertaken a countercyclical behavior, against trend or against the cycle and for investing in financial markets with the probability in favor we need a map that comes from the statistics.

  5. Awareness Reduces Racial Bias

    OpenAIRE

    2014-01-01

    Can raising awareness of racial bias subsequently reduce that bias? We address this question by exploiting the widespread media attention highlighting racial bias among professional basketball referees that occurred in May 2007 following the release of an academic study. Using new data, we confirm that racial bias persisted in the years after the study's original sample, but prior to the media coverage. Subsequent to the media coverage though, the bias completely disappeared. We examine poten...

  6. Belief bias and relational reasoning.

    Science.gov (United States)

    Roberts, Maxwell J; Sykes, Elizabeth D A

    2003-01-01

    When people evaluate categorical syllogisms, they tend to reject unbelievable conclusions and accept believable ones irrespective of their validity. Typically, this effect is particularly marked for invalid conclusions that are possible, but do not necessarily follow, given the premises. However, smaller believability effects can also be detected for other types of conclusion. Three experiments are reported here, in which an attempt was made to determine whether belief bias effects can manifest themselves on the relational inference task. Subjects evaluated the validity of conclusions such as William the Conqueror was king after the Pyramids were built (temporal task) or Manchester is north of Bournemouth (spatial task) with respect to their premises. All of the major findings for equivalent categorical syllogism tasks were replicated. However, the overall size of the main effect of believability appears to be related to task presentation, a phenomenon not previously identified for categorical syllogisms and which current theories of belief bias have difficulty explaining.

  7. A catalog of biases in questionnaires.

    Science.gov (United States)

    Choi, Bernard C K; Pak, Anita W P

    2005-01-01

    Bias in questionnaires is an important issue in public health research. To collect the most accurate data from respondents, investigators must understand and be able to prevent or at least minimize bias in the design of their questionnaires. This paper identifies and categorizes 48 types of bias in questionnaires based on a review of the literature and offers an example of each type. The types are categorized according to three main sources of bias: the way a question is designed, the way the questionnaire as a whole is designed, and how the questionnaire is administered. This paper is intended to help investigators in public health understand the mechanism and dynamics of problems in questionnaire design and to provide a checklist for identifying potential bias in a questionnaire before it is administered.

  8. Professional Culture and Climate: Addressing Unconscious Bias

    Science.gov (United States)

    Knezek, Patricia

    2016-10-01

    Unconscious bias reflects expectations or stereotypes that influence our judgments of others (regardless of our own group). Everyone has unconscious biases. The end result of unconscious bias can be an accumulation of advantage or disadvantage that impacts the long term career success of individuals, depending on which biases they are subject to. In order to foster a professional culture and climate, being aware of these unconscious biases and mitigating against them is a first step. This is particularly important when judgements are needed, such as in cases for recruitment, choice of speakers for conferences, and even reviewing papers submitted for publication. This presentation will cover how unconscious bias manifests itself, what evidence exists to demonstrate it exists, and ways it can be addressed.

  9. Medical journal peer review: process and bias.

    Science.gov (United States)

    Manchikanti, Laxmaiah; Kaye, Alan D; Boswell, Mark V; Hirsch, Joshua A

    2015-01-01

    Scientific peer review is pivotal in health care research in that it facilitates the evaluation of findings for competence, significance, and originality by qualified experts. While the origins of peer review can be traced to the societies of the eighteenth century, it became an institutionalized part of the scholarly process in the latter half of the twentieth century. This was a response to the growth of research and greater subject specialization. With the current increase in the number of specialty journals, the peer review process continues to evolve to meet the needs of patients, clinicians, and policy makers. The peer review process itself faces challenges. Unblinded peer review might suffer from positive or negative bias towards certain authors, specialties, and institutions. Peer review can also suffer when editors and/or reviewers might be unable to understand the contents of the submitted manuscript. This can result in an inability to detect major flaws, or revelations of major flaws after acceptance of publication by the editors. Other concerns include potentially long delays in publication and challenges uncovering plagiarism, duplication, corruption and scientific misconduct. Conversely, a multitude of these challenges have led to claims of scientific misconduct and an erosion of faith. These challenges have invited criticism of the peer review process itself. However, despite its imperfections, the peer review process enjoys widespread support in the scientific community. Peer review bias is one of the major focuses of today's scientific assessment of the literature. Various types of peer review bias include content-based bias, confirmation bias, bias due to conservatism, bias against interdisciplinary research, publication bias, and the bias of conflicts of interest. Consequently, peer review would benefit from various changes and improvements with appropriate training of reviewers to provide quality reviews to maintain the quality and integrity of

  10. Factors associated with results and conclusions of trials of thiazolidinediones.

    Directory of Open Access Journals (Sweden)

    Gail Rattinger

    Full Text Available BACKGROUND: When a sponsor funds a study of two competing drugs in a head-to-head comparison, the results and conclusions are likely to favor the sponsor's drug. Thiazolidinediones, oral medications used for the treatment of type 2 diabetes, are one of the most costly choices of oral anti-diabetic medications, yet they do not demonstrate clinically relevant differences in achieving lower glycosylated hemoglobin levels compared to other oral antidiabetic drugs. Our aim is to examine associations between research funding source, study design characteristics aimed at reducing bias, and other factors with the results and conclusions of randomized controlled trials (RCTs of thiazolidinediones compared to other oral hypoglycemic agents. METHODS AND FINDINGS: This is a cross-sectional study of 61 published RCTs comparing a thiazolidinedione (glitazone to another anti-diabetic drug or placebo for treatment of type 2 diabetes. Data on study design characteristics, funding source, author's financial ties, results for primary outcomes, and author conclusions were extracted. Univariate logistic regression identified associations between independent variables and results and conclusions that favored the glitazone. Of the RCTs, 59% (36/61 were funded by industry, 39% (24/61 did not disclose any funding. Common study design weaknesses included inadequate blinding and lack of concealment of allocation. Trials that reported favorable glycemic control results for the glitazone were more likely to have adequate blinding (OR (95% CI = 5.42 (1.46, 21.19, p = 0.008 and have a corresponding author with financial ties to the glitazone manufacturer (OR (95% CI = 4.12 (1.05, 19.53; p = 0.04. Trials with conclusions favoring the glitazone were less likely to be funded by a comparator drug company than a glitazone company (OR (95% CI = 0.026 (0, 0.40, p = 0.003 and less likely to be published in journals with higher impact factors (OR (95% CI = 0.79 (0.62, 0.97, p = 0

  11. Reporting Bias in Clinical Trials Investigating the Efficacy of Second-Generation Antidepressants in the Treatment of Anxiety Disorders: A Report of 2 Meta-analyses.

    Science.gov (United States)

    Roest, Annelieke M; de Jonge, Peter; Williams, Craig D; de Vries, Ymkje Anna; Schoevers, Robert A; Turner, Erick H

    2015-05-01

    Studies have shown that the scientific literature has overestimated the efficacy of antidepressants for depression, but other indications for these drugs have not been considered. To examine reporting biases in double-blind, placebo-controlled trials on the pharmacologic treatment of anxiety disorders and quantify the extent to which these biases inflate estimates of drug efficacy. We included reviews obtained from the US Food and Drug Administration (FDA) for premarketing trials of 9 second-generation antidepressants in the treatment of anxiety disorders. A systematic search for matching publications (until December 19, 2012) was performed using PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials. Double data extraction was performed for the FDA reviews and the journal articles. The Hedges g value was calculated as the measure of effect size. Reporting bias was examined and classified as study publication bias, outcome reporting bias, or spin (abstract conclusion not consistent with published results on primary end point). Separate meta-analyses were conducted for the 2 sources, and the effect of publication status on the effect estimates was examined using meta-regression. The findings of 41 of the 57 trials (72%) were positive according to the FDA, but 43 of the 45 published article conclusions (96%) were positive (P antidepressants for anxiety disorders. Although these biases did not significantly inflate estimates of drug efficacy, reporting biases led to significant increases in the number of positive findings in the literature.

  12. Self-Consciousness and Bias in Social Interaction.

    Science.gov (United States)

    Sandelands, Lloyd E.; Stablein, Ralph E.

    1986-01-01

    Investigated whether trait differences in self-consciousness would account for egocentric attribution bias in social interaction. Bias was greater for high public self-consciousness. Public self-consciousness had no effect in the Interaction Unimportant Condition where social interaction was not salient. Contrary to prediction, however, the…

  13. 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.

  14. On commercial media bias

    OpenAIRE

    Germano, Fabrizio

    2008-01-01

    Within the spokes model of Chen and Riordan (2007) that allows for non-localized competition among arbitrary numbers of media outlets, we quantify the effect of concentration of ownership on quality and bias of media content. A main result shows that too few commercial outlets, or better, too few separate owners of commercial outlets can lead to substantial bias in equilibrium. Increasing the number of outlets (commercial and non-commercial) tends to bring down this bias; but the strongest ef...

  15. Interpretation biases in paranoia.

    Science.gov (United States)

    Savulich, George; Freeman, Daniel; Shergill, Sukhi; Yiend, Jenny

    2015-01-01

    Information in the environment is frequently ambiguous in meaning. Emotional ambiguity, such as the stare of a stranger, or the scream of a child, encompasses possible good or bad emotional consequences. Those with elevated vulnerability to affective disorders tend to interpret such material more negatively than those without, a phenomenon known as "negative interpretation bias." In this study we examined the relationship between vulnerability to psychosis, measured by trait paranoia, and interpretation bias. One set of material permitted broadly positive/negative (valenced) interpretations, while another allowed more or less paranoid interpretations, allowing us to also investigate the content specificity of interpretation biases associated with paranoia. Regression analyses (n=70) revealed that trait paranoia, trait anxiety, and cognitive inflexibility predicted paranoid interpretation bias, whereas trait anxiety and cognitive inflexibility predicted negative interpretation bias. In a group comparison those with high levels of trait paranoia were negatively biased in their interpretations of ambiguous information relative to those with low trait paranoia, and this effect was most pronounced for material directly related to paranoid concerns. Together these data suggest that a negative interpretation bias occurs in those with elevated vulnerability to paranoia, and that this bias may be strongest for material matching paranoid beliefs. We conclude that content-specific biases may be important in the cause and maintenance of paranoid symptoms.

  16. Political bias is tenacious.

    Science.gov (United States)

    Ditto, Peter H; Wojcik, Sean P; Chen, Eric Evan; Grady, Rebecca Hofstein; Ringel, Megan M

    2015-01-01

    Duarte et al. are right to worry about political bias in social psychology but they underestimate the ease of correcting it. Both liberals and conservatives show partisan bias that often worsens with cognitive sophistication. More non-liberals in social psychology is unlikely to speed our convergence upon the truth, although it may broaden the questions we ask and the data we collect.

  17. 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

  18. Bias in Peripheral Depression Biomarkers

    DEFF Research Database (Denmark)

    Carvalho, André F; Köhler, Cristiano A; Brunoni, André R

    2016-01-01

    BACKGROUND: To aid in the differentiation of individuals with major depressive disorder (MDD) from healthy controls, numerous peripheral biomarkers have been proposed. To date, no comprehensive evaluation of the existence of bias favoring the publication of significant results or inflating effect...... sizes has been conducted. METHODS: Here, we performed a comprehensive review of meta-analyses of peripheral nongenetic biomarkers that could discriminate individuals with MDD from nondepressed controls. PubMed/MEDLINE, EMBASE, and PsycINFO databases were searched through April 10, 2015. RESULTS: From 15...

  19. The Effectiveness of Cognitive Bias Modification Interventions for Substance Addictions: A Meta-Analysis

    Science.gov (United States)

    Kok, Robin N.; Cuijpers, Pim

    2016-01-01

    Background and Aims Cognitive bias modification (CBM) interventions, presumably targeting automatic processes, are considered particularly promising for addictions. We conducted a meta-analysis examining randomized controlled trials (RCTs) of CBM for substance addiction outcomes. Methods Studies were identified through systematic searches in bibliographical databases. We included RCTs of CBM interventions, alone or in combination with other treatments, for any type of addiction. We examined trial risk of bias, publication bias and possible moderators. Effects sizes were computed for post-test and follow-up, using a random-effects model. We grouped outcome measures and reported results for addiction (all related measures), craving and cognitive bias. Results We identified 25 trials, 18 for alcohol problems, and 7 for smoking. At post-test, there was no significant effect of CBM for addiction, g = 0.08 (95% CI -0.02 to 0.18) or craving, g = 0.05 (95% CI -0.06 to 0.16), but there was a significant, moderate effect on cognitive bias, g = 0.60 (95% CI 0.39 to 0.79). Results were similar for alcohol and smoking outcomes taken separately. Follow-up addiction outcomes were reported in 7 trials, resulting in a small but significant effect of CBM, g = 0.18 (95% CI 0.03 to 0.32). Results for addiction and craving did not differ by substance type, sample type, delivery setting, bias targeted or number of sessions. Risk of bias was high or uncertain in most trials, for most criteria considered. Meta-regression analyses revealed significant inverse relationships between risk of bias and effect sizes for addiction outcomes and craving. The relationship between cognitive bias and respectively addiction ESs was not significant. There was consistent evidence of publication bias in the form of funnel plot asymmetry. Conclusions Our results cast serious doubts on the clinical utility of CBM interventions for addiction problems, but sounder methodological trials are necessary before

  20. Media Bias and Reputation

    OpenAIRE

    Matthew Gentzkow; Jesse M. Shapiro

    2005-01-01

    A Bayesian consumer who is uncertain about the quality of an information source will infer that the source is of higher quality when its reports conform to the consumer's prior expectations. We use this fact to build a model of media bias in which firms slant their reports toward the prior beliefs of their customers in order to build a reputation for quality. Bias emerges in our model even though it can make all market participants worse off. The model predicts that bias will be less severe w...

  1. Biased predecision processing.

    Science.gov (United States)

    Brownstein, Aaron L

    2003-07-01

    Decision makers conduct biased predecision processing when they restructure their mental representation of the decision environment to favor one alternative before making their choice. The question of whether biased predecision processing occurs has been controversial since L. Festinger (1957) maintained that it does not occur. The author reviews relevant research in sections on theories of cognitive dissonance, decision conflict, choice certainty, action control, action phases, dominance structuring, differentiation and consolidation, constructive processing, motivated reasoning, and groupthink. Some studies did not find evidence of biased predecision processing, but many did. In the Discussion section, the moderators are summarized and used to assess the theories.

  2. Modeling confirmation bias and polarization

    CERN Document Server

    Del Vicario, Michela; Caldarelli, Guido; Stanley, H Eugene; Quattrociocchi, Walter

    2016-01-01

    Online users tend to select claims that adhere to their system of beliefs and to ignore dissenting information. Confirmation bias, indeed, plays a pivotal role in viral phenomena. Furthermore, the wide availability of content on the web fosters the aggregation of likeminded people where debates tend to enforce group polarization. Such a configuration might alter the public debate and thus the formation of the public opinion. In this paper we provide a mathematical model to study online social debates and the related polarization dynamics. We assume the basic updating rule of the Bounded Confidence Model (BCM) and we develop two variations a) the Rewire with Bounded Confidence Model (RBCM), in which discordant links are broken until convergence is reached; and b) the Unbounded Confidence Model, under which the interaction among discordant pairs of users is allowed even with a negative feedback, either with the rewiring step (RUCM) or without it (UCM). From numerical simulations we find that the new models (UCM...

  3. Pharmaceutical Sponsorship Bias Influences Thrombolytic Literature in Acute Ischemic Stroke

    Directory of Open Access Journals (Sweden)

    Ryan P Radecki

    2011-05-01

    Full Text Available Background: The efficacy of thrombolytic therapy for acute ischemic stroke remains controversial in Emergency Medicine and has not been fully endorsed by either the American College of Emergency Physicians or the American Academy of emergency medicine. A growing recognition exists of the influence of pharmaceutical sponsorship on the reported findings of published clinical trials. Sponsorship bias has been suggested as a potential criticism of the literature and guidelines favoring thrombolytic therapy. Objective: The objective of this study is to review the most influential literature regarding thrombolytic therapy for acute ischemic stroke and document the presence or absence of pharmaceutical sponsorship. Methods: A publication-citation analysis was performed to identify the most frequently cited articles pertaining to thrombolytic therapy for acute ischemic stroke. Identified articles were reviewed for disclosures of pharmaceutical funding. Results: Of the 20 most-cited articles pertaining to thrombolytic therapy for acute stroke, 17 (85% disclosed pharmaceutical sponsorship. These disclosures range from general sponsorship to direct employment of authors by pharmaceutical companies. Conclusion: An overwhelming predominance of the most influential literature regarding thrombolytic therapy for acute ischemic stroke is susceptible to sponsorship bias. This potential bias may provide a basis for physician concern regarding the efficacy and safety of thrombolytic therapy. Further, large, independent, placebo-controlled studies may be required to guide therapy and professional guidelines definitively for acute ischemic stroke. [West J Emerg Med. 2011;12(4:435–441.

  4. Information bias in health research: definition, pitfalls, and adjustment methods.

    Science.gov (United States)

    Althubaiti, Alaa

    2016-01-01

    As with other fields, medical sciences are subject to different sources of bias. While understanding sources of bias is a key element for drawing valid conclusions, bias in health research continues to be a very sensitive issue that can affect the focus and outcome of investigations. Information bias, otherwise known as misclassification, is one of the most common sources of bias that affects the validity of health research. It originates from the approach that is utilized to obtain or confirm study measurements. This paper seeks to raise awareness of information bias in observational and experimental research study designs as well as to enrich discussions concerning bias problems. Specifying the types of bias can be essential to limit its effects and, the use of adjustment methods might serve to improve clinical evaluation and health care practice.

  5. Berkson’s bias, selection bias, and missing data

    OpenAIRE

    Westreich, Daniel

    2012-01-01

    While Berkson’s bias is widely recognized in the epidemiologic literature, it remains underappreciated as a model of both selection bias and bias due to missing data. Simple causal diagrams and 2×2 tables illustrate how Berkson’s bias connects to collider bias and selection bias more generally, and show the strong analogies between Berksonian selection bias and bias due to missing data. In some situations, considerations of whether data are missing at random or missing not at random is less i...

  6. 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.

  7. Economic Costs of Bias-Based Bullying

    Science.gov (United States)

    Baams, Laura; Talmage, Craig A.; Russell, Stephen T.

    2017-01-01

    Because many school districts receive funding based on student attendance, absenteeism results in a high cost for the public education system. This study shows the direct links between bias-based bullying, school absenteeism because of feeling unsafe at school, and loss of funds for school districts in California. Data from the 2011-2013…

  8. Increasingly minimal bias routing

    Energy Technology Data Exchange (ETDEWEB)

    Bataineh, Abdulla; Court, Thomas; Roweth, Duncan

    2017-02-21

    A system and algorithm configured to generate diversity at the traffic source so that packets are uniformly distributed over all of the available paths, but to increase the likelihood of taking a minimal path with each hop the packet takes. This is achieved by configuring routing biases so as to prefer non-minimal paths at the injection point, but increasingly prefer minimal paths as the packet proceeds, referred to herein as Increasing Minimal Bias (IMB).

  9. Biased causal inseparable game

    CERN Document Server

    Bhattacharya, Some Sankar

    2015-01-01

    Here we study the \\emph{causal inseparable} game introduced in [\\href{http://www.nature.com/ncomms/journal/v3/n10/full/ncomms2076.html}{Nat. Commun. {\\bf3}, 1092 (2012)}], but it's biased version. Two separated parties, Alice and Bob, generate biased bits (say input bit) in their respective local laboratories. Bob generates another biased bit (say decision bit) which determines their goal: whether Alice has to guess Bob's bit or vice-verse. Under the assumption that events are ordered with respect to some global causal relation, we show that the success probability of this biased causal game is upper bounded, giving rise to \\emph{biased causal inequality} (BCI). In the \\emph{process matrix} formalism, which is locally in agreement with quantum physics but assume no global causal order, we show that there exist \\emph{inseparable} process matrices that violate the BCI for arbitrary bias in the decision bit. In such scenario we also derive the maximal violation of the BCI under local operations involving tracele...

  10. Public inquiry related to the request by EDF of a definitive stopping and complete dismantling of the hardware storage installation of the Monts d'Arree nuclear power plant (INB n.162). Opinion and conclusions of the inquiry commission; Enquete publique relative a la demande, presentee par EDF, de mise a l'arret definitif et de demantelement complet de l'installation d'entreposage de materiels de la centrale nucleaire des Monts d'Arree (INB n.162). Avis et conclusions de la commission d'enquete

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-03-15

    After a recall of the project of stopping and dismantling of the hardware storage installation (INB n.162) which had been created after the stopping and dismantling of the Monts d'Arree heavy water nuclear reactor (INB n.28), this report analyzes the results of the public inquiry, and highlights the arguments of those in favour of this project and those opposed to it. Then, it states the Inquiry Commission's opinion which addresses the request for a national public debate, the project justification, the inquiry file, the site radiological status, the site radiological control during works, the impacts of dismantling, the various risks (for the population and the workers, in terms of fire risks), the issue of radioactive wastes, economic aspects (costs, jobs, local economy, tourism and site image), and site reconversion

  11. Hindsight bias and outcome bias in the social construction of medical negligence: a review.

    Science.gov (United States)

    Hugh, Thomas B; Dekker, Sidney W A

    2009-05-01

    Medical negligence has been the subject of much public debate in recent decades. Although the steep increase in the frequency and size of claims against doctors at the end of the last century appears to have plateaued, in Australia at least, medical indemnity costs and consequences are still a matter of concern for doctors, medical defence organisations and governments in most developed countries. Imprecision in the legal definition of negligence opens the possibility that judgments of this issue at several levels may be subject to hindsight and outcome bias. Hindsight bias relates to the probability of an adverse event perceived by a retrospective observer ("I would have known it was going to happen"), while outcome bias is a largely subconscious cognitive distortion produced by the observer's knowledge of the adverse outcome. This review examines the relevant legal, medical, psychological and sociological literature on the operation of these pervasive and universal biases in the retrospective evaluation of adverse events. A finding of medical negligence is essentially an after-the-event social construction and is invariably affected by hindsight bias and knowledge of the adverse outcome. Such biases obviously pose a threat to the fairness of judgments. A number of debiasing strategies have been suggested but are relatively ineffective because of the universality and strength of these biases and the inherent difficulty of concealing from expert witnesses knowledge of the outcome. Education about the effect of the biases is therefore important for lawyers, medical expert witnesses and the judiciary.

  12. Immortal Time Bias: A Frequently Unrecognized Threat to Validity in the Evaluation of Postoperative Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Park, Henry S. [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT (United States); Gross, Cary P. [Cancer Outcomes Policy and Effectiveness Research Center, Yale University School of Medicine, New Haven, CT (United States); Makarov, Danil V. [Department of Urology, New York University School of Medicine, New York, NY (United States); Yu, James B., E-mail: james.b.yu@yale.edu [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT (United States); Cancer Outcomes Policy and Effectiveness Research Center, Yale University School of Medicine, New Haven, CT (United States)

    2012-08-01

    Purpose: To evaluate the influence of immortal time bias on observational cohort studies of postoperative radiotherapy (PORT) and the effectiveness of sequential landmark analysis to account for this bias. Methods and Materials: First, we reviewed previous studies of the Surveillance, Epidemiology, and End Results (SEER) database to determine how frequently this bias was considered. Second, we used SEER to select three tumor types (glioblastoma multiforme, Stage IA-IVM0 gastric adenocarcinoma, and Stage II-III rectal carcinoma) for which prospective trials demonstrated an improvement in survival associated with PORT. For each tumor type, we calculated conditional survivals and adjusted hazard ratios of PORT vs. postoperative observation cohorts while restricting the sample at sequential monthly landmarks. Results: Sixty-two percent of previous SEER publications evaluating PORT failed to use a landmark analysis. As expected, delivery of PORT for all three tumor types was associated with improved survival, with the largest associated benefit favoring PORT when all patients were included regardless of survival. Preselecting a cohort with a longer minimum survival sequentially diminished the apparent benefit of PORT. Conclusions: Although the majority of previous SEER articles do not correct for it, immortal time bias leads to altered estimates of PORT effectiveness, which are very sensitive to landmark selection. We suggest the routine use of sequential landmark analysis to account for this bias.

  13. Mechanisms and direction of allocation bias in randomised clinical trials

    DEFF Research Database (Denmark)

    Paludan-Müller, Asger Sand; Laursen, David R. T.; Hróbjartsson, Asbjørn

    2016-01-01

    clinical trials. METHODS: Two systematic reviews and a theoretical analysis. We conducted one systematic review of empirical studies of motives/methods for deciphering patient allocation sequences; and another review of methods publications commenting on allocation bias. We theoretically analysed...

  14. Gender Bias in Testing: Current Debates for Future Priorities. A Public Policy Dialogue. Proceedings of the Ford Foundation Women's Program Forum (2nd, New York, New York, April 1989).

    Science.gov (United States)

    Rosser, Phyllis; And Others

    In April 1989, the Women's Program Forum of the Ford Foundation sponsored a seminar that examined the current debates and future directions surrounding the issue of gender bias in testing, with particular attention to the Scholastic Aptitude Test (SAT). This booklet provides a transcript of the proceedings of the forum. P. Rosser's presentation of…

  15. Distinguishing Selection Bias and Confounding Bias in Comparative Effectiveness Research.

    Science.gov (United States)

    Haneuse, Sebastien

    2016-04-01

    Comparative effectiveness research (CER) aims to provide patients and physicians with evidence-based guidance on treatment decisions. As researchers conduct CER they face myriad challenges. Although inadequate control of confounding is the most-often cited source of potential bias, selection bias that arises when patients are differentially excluded from analyses is a distinct phenomenon with distinct consequences: confounding bias compromises internal validity, whereas selection bias compromises external validity. Despite this distinction, however, the label "treatment-selection bias" is being used in the CER literature to denote the phenomenon of confounding bias. Motivated by an ongoing study of treatment choice for depression on weight change over time, this paper formally distinguishes selection and confounding bias in CER. By formally distinguishing selection and confounding bias, this paper clarifies important scientific, design, and analysis issues relevant to ensuring validity. First is that the 2 types of biases may arise simultaneously in any given study; even if confounding bias is completely controlled, a study may nevertheless suffer from selection bias so that the results are not generalizable to the patient population of interest. Second is that the statistical methods used to mitigate the 2 biases are themselves distinct; methods developed to control one type of bias should not be expected to address the other. Finally, the control of selection and confounding bias will often require distinct covariate information. Consequently, as researchers plan future studies of comparative effectiveness, care must be taken to ensure that all data elements relevant to both confounding and selection bias are collected.

  16. Measuring Agricultural Bias

    DEFF Research Database (Denmark)

    Jensen, Henning Tarp; Robinson, Sherman; Tarp, Finn

    . For the 15 sample countries, the results indicate that the agricultural price incentive bias, which was generally perceived to exist during the 1980s, was largely eliminated during the 1990s. The results also demonstrate that general equilibrium effects and country-specific characteristics - including trade...... shares and intersectoral linkages - are crucial for determining the sign and magnitude of trade policy bias. The GE-ERP measure is therefore uniquely suited to capture the full impact of trade policies on agricultural price incentives. A Monte Carlo procedure confirms that the results are robust...

  17. Measuring agricultural policy bias

    DEFF Research Database (Denmark)

    Jensen, Henning Tarp; Robinson, Sherman; Tarp, Finn

    2010-01-01

    Measurement is a key issue in the literature on price incentive bias induced by trade policy. We introduce a general equilibrium measure of the relative effective rate of protection, which generalizes earlier protection measures. For our fifteen sample countries, results indicate that the agricul......Measurement is a key issue in the literature on price incentive bias induced by trade policy. We introduce a general equilibrium measure of the relative effective rate of protection, which generalizes earlier protection measures. For our fifteen sample countries, results indicate...... protection measure is therefore uniquely suited to capture the full impact of trade policies on relative agricultural price incentives....

  18. Quantifying selective reporting and the Proteus phenomenon for multiple datasets with similar bias.

    Directory of Open Access Journals (Sweden)

    Thomas Pfeiffer

    Full Text Available Meta-analyses play an important role in synthesizing evidence from diverse studies and datasets that address similar questions. A major obstacle for meta-analyses arises from biases in reporting. In particular, it is speculated that findings which do not achieve formal statistical significance are less likely reported than statistically significant findings. Moreover, the patterns of bias can be complex and may also depend on the timing of the research results and their relationship with previously published work. In this paper, we present an approach that is specifically designed to analyze large-scale datasets on published results. Such datasets are currently emerging in diverse research fields, particularly in molecular medicine. We use our approach to investigate a dataset on Alzheimer's disease (AD that covers 1167 results from case-control studies on 102 genetic markers. We observe that initial studies on a genetic marker tend to be substantially more biased than subsequent replications. The chances for initial, statistically non-significant results to be published are estimated to be about 44% (95% CI, 32% to 63% relative to statistically significant results, while statistically non-significant replications have almost the same chance to be published as statistically significant replications (84%; 95% CI, 66% to 107%. Early replications tend to be biased against initial findings, an observation previously termed Proteus phenomenon: The chances for non-significant studies going in the same direction as the initial result are estimated to be lower than the chances for non-significant studies opposing the initial result (73%; 95% CI, 55% to 96%. Such dynamic patterns in bias are difficult to capture by conventional methods, where typically simple publication bias is assumed to operate. Our approach captures and corrects for complex dynamic patterns of bias, and thereby helps generating conclusions from published results that are more robust

  19. 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.

  20. Understanding antigay bias from a cognitive-affective-behavioral perspective.

    Science.gov (United States)

    Callender, Kevin A

    2015-01-01

    In general, United States citizens have become increasingly more accepting of lesbians and gay men over the past few decades. Despite this shift in public attitudes, antigay bias remains openly tolerated, accepted, practiced, and even defended by a substantial portion of the population. This article reviews why and how antigay bias persists using a cognitive-affective-behavioral perspective that touches on sociocognitive factors such as prejudice and stereotyping, as well as features unique to antigay bias, such as its concealable nature. The article concludes with a discussion of how understanding modern antigay bias through a cognitive-affective-behavioral lens can be applied to reduce discrimination against gays and lesbians.

  1. Simulating currency substitution bias

    NARCIS (Netherlands)

    M. Boon (Martin); C.J.M. Kool (Clemens); C.G. de Vries (Casper)

    1989-01-01

    textabstractThe sign and size of estimates of the elasticity of currency substitution critically depend on the definition of the oppurtunity costs of holding money. We investigate possible biases by means of Monte Carlo experiments, as sufficient real data are not available.

  2. Sex Bias in Children.

    Science.gov (United States)

    Zalk, Sue Rosenberg; And Others

    This study investigated children's sex biased attitudes as a function of the sex, age, and race of the child as well as a geographical-SES factor. Two attitudes were measured on a 55-item questionnaire: Sex Pride (attributing positive characteristics to a child of the same sex) and Sex Prejudice (attributing negative characteristics to a child of…

  3. The public health risks of media violence: a meta-analytic review.

    Science.gov (United States)

    Ferguson, Christopher J; Kilburn, John

    2009-05-01

    To conduct a meta-analytic review of studies that examine the impact of violent media on aggressive behavior and to determine whether this effect could be explained through methodological problems inherent in this research field. A detailed literature search identified peer-reviewed articles addressing media violence effects. Effect sizes were calculated for all studies. Effect sizes were adjusted for observed publication bias. Publication bias was a problem for studies of aggressive behavior, and methodological problems such as the use of poor aggression measures inflated effect size. Once corrected for publication bias, studies of media violence effects provided little support for the hypothesis that media violence is associated with higher aggression. The corrected overall effect size for all studies was r = .08. Results from the current analysis do not support the conclusion that media violence leads to aggressive behavior. It cannot be concluded at this time that media violence presents a significant public health risk.

  4. Standards, accuracy, and questions of bias in Rorschach meta-analyses: reply to Wood, Garb, Nezworski, Lilienfeld, and Duke (2015).

    Science.gov (United States)

    Mihura, Joni L; Meyer, Gregory J; Bombel, George; Dumitrascu, Nicolae

    2015-01-01

    Wood, Garb, Nezworski, Lilienfeld, and Duke (2015) found our systematic review and meta-analyses of 65 Rorschach variables to be accurate and unbiased, and hence removed their previous recommendation for a moratorium on the applied use of the Rorschach. However, Wood et al. (2015) hypothesized that publication bias would exist for 4 Rorschach variables. To test this hypothesis, they replicated our meta-analyses for these 4 variables and added unpublished dissertations to the pool of articles. In the process, they used procedures that contradicted their standards and recommendations for sound Rorschach research, which consistently led to significantly lower effect sizes. In reviewing their meta-analyses, we found numerous methodological errors, data errors, and omitted studies. In contrast to their strict requirements for interrater reliability in the Rorschach meta-analyses of other researchers, they did not report interrater reliability for any of their coding and classification decisions. In addition, many of their conclusions were based on a narrative review of individual studies and post hoc analyses rather than their meta-analytic findings. Finally, we challenge their sole use of dissertations to test publication bias because (a) they failed to reconcile their conclusion that publication bias was present with the analyses we conducted showing its absence, and (b) we found numerous problems with dissertation study quality. In short, one cannot rely on the findings or the conclusions reported in Wood et al.

  5. Opinion Dynamics with Confirmation Bias

    Science.gov (United States)

    Allahverdyan, Armen E.; Galstyan, Aram

    2014-01-01

    Background 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. Methodology/Principal Findings 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. Conclusions 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. PMID:25007078

  6. Artificial bias typically neglected in comparisons of uncertain atmospheric data

    Science.gov (United States)

    Pitkänen, Mikko R. A.; Mikkonen, Santtu; Lehtinen, Kari E. J.; Lipponen, Antti; Arola, Antti

    2016-09-01

    Publications in atmospheric sciences typically neglect biases caused by regression dilution (bias of the ordinary least squares line fitting) and regression to the mean (RTM) in comparisons of uncertain data. We use synthetic observations mimicking real atmospheric data to demonstrate how the biases arise from random data uncertainties of measurements, model output, or satellite retrieval products. Further, we provide examples of typical methods of data comparisons that have a tendency to pronounce the biases. The results show, that data uncertainties can significantly bias data comparisons due to regression dilution and RTM, a fact that is known in statistics but disregarded in atmospheric sciences. Thus, we argue that often these biases are widely regarded as measurement or modeling errors, for instance, while they in fact are artificial. It is essential that atmospheric and geoscience communities become aware of and consider these features in research.

  7. Temperature trend biases

    Science.gov (United States)

    Venema, Victor; Lindau, Ralf

    2016-04-01

    In an accompanying talk we show that well-homogenized national dataset warm more than temperatures from global collections averaged over the region of common coverage. In this poster we want to present auxiliary work about possible biases in the raw observations and on how well relative statistical homogenization can remove trend biases. There are several possible causes of cooling biases, which have not been studied much. Siting could be an important factor. Urban stations tend to move away from the centre to better locations. Many stations started inside of urban areas and are nowadays more outside. Even for villages the temperature difference between the centre and edge can be 0.5°C. When a city station moves to an airport, which often happened around WWII, this takes the station (largely) out of the urban heat island. During the 20th century the Stevenson screen was established as the dominant thermometer screen. This screen protected the thermometer much better against radiation than earlier designs. Deficits of earlier measurement methods have artificially warmed the temperatures in the 19th century. Newer studies suggest we may have underestimated the size of this bias. Currently we are in a transition to Automatic Weather Stations. The net global effect of this transition is not clear at this moment. Irrigation on average decreases the 2m-temperature by about 1 degree centigrade. At the same time, irrigation has increased significantly during the last century. People preferentially live in irrigated areas and weather stations serve agriculture. Thus it is possible that there is a higher likelihood that weather stations are erected in irrigated areas than elsewhere. In this case irrigation could lead to a spurious cooling trend. In the Parallel Observations Science Team of the International Surface Temperature Initiative (ISTI-POST) we are studying influence of the introduction of Stevenson screens and Automatic Weather Stations using parallel measurements

  8. Bias in collegiate courts

    OpenAIRE

    Olowofoyeku, AA

    2016-01-01

    This article addresses the issues attending common law collegiate courts’ engagements with allegations of bias within their own ranks. It will be argued that, in such cases, it would be inappropriate to involve the collegiate panel or any member thereof in the decision, since such involvement inevitably encounters difficulties. The common law’s dilemmas require drastic solutions, but the common law arguably is illequipped to implement the required change. The answer, it will be argued, is ...

  9. Number of objectives and conclusions in dissertations and thesis

    Directory of Open Access Journals (Sweden)

    Liebano Richard Eloin

    2005-01-01

    Full Text Available PURPOSE: To analyze the number of objectives and conclusions presented in dissertations and thesis defended at Federal University of São Paulo - Paulista School of Medicine (UNIFESP - EPM. METHODS: It was realized a search in the master degree dissertations and doctor degree thesis defended at Federal University of São Paulo - Paulista School of Medicine in the years 2002 and 2003 that were found available in the central library of this university. RESULTS: From 723 master dissertations analyzed, 62 (8,57% presented only one objective and one conclusion, 134 (18,53% presented one objective and more than one conclusion and 527 (72,89% had more than one objective and more than one conclusion. From 502 doctor thesis analyzed, 23 (4,58% presented only one objective and one conclusion, 123 (24,50% presented one objective and more than one conclusion and 376 (74,90% had more than one objective and more than one conclusion.. CONCLUSIONS: It wasn't found in researched literature the number of objectives and conclusions a scientific work must have. A highest number of thesis and dissertations presented more than one objective and more than one conclusion.

  10. Modeling confirmation bias and polarization

    Science.gov (United States)

    Del Vicario, Michela; Scala, Antonio; Caldarelli, Guido; Stanley, H. Eugene; Quattrociocchi, Walter

    2017-01-01

    Online users tend to select claims that adhere to their system of beliefs and to ignore dissenting information. Confirmation bias, indeed, plays a pivotal role in viral phenomena. Furthermore, the wide availability of content on the web fosters the aggregation of likeminded people where debates tend to enforce group polarization. Such a configuration might alter the public debate and thus the formation of the public opinion. In this paper we provide a mathematical model to study online social debates and the related polarization dynamics. We assume the basic updating rule of the Bounded Confidence Model (BCM) and we develop two variations a) the Rewire with Bounded Confidence Model (RBCM), in which discordant links are broken until convergence is reached; and b) the Unbounded Confidence Model, under which the interaction among discordant pairs of users is allowed even with a negative feedback, either with the rewiring step (RUCM) or without it (UCM). From numerical simulations we find that the new models (UCM and RUCM), unlike the BCM, are able to explain the coexistence of two stable final opinions, often observed in reality. Lastly, we present a mean field approximation of the newly introduced models. PMID:28074874

  11. Modeling confirmation bias and polarization

    Science.gov (United States)

    Del Vicario, Michela; Scala, Antonio; Caldarelli, Guido; Stanley, H. Eugene; Quattrociocchi, Walter

    2017-01-01

    Online users tend to select claims that adhere to their system of beliefs and to ignore dissenting information. Confirmation bias, indeed, plays a pivotal role in viral phenomena. Furthermore, the wide availability of content on the web fosters the aggregation of likeminded people where debates tend to enforce group polarization. Such a configuration might alter the public debate and thus the formation of the public opinion. In this paper we provide a mathematical model to study online social debates and the related polarization dynamics. We assume the basic updating rule of the Bounded Confidence Model (BCM) and we develop two variations a) the Rewire with Bounded Confidence Model (RBCM), in which discordant links are broken until convergence is reached; and b) the Unbounded Confidence Model, under which the interaction among discordant pairs of users is allowed even with a negative feedback, either with the rewiring step (RUCM) or without it (UCM). From numerical simulations we find that the new models (UCM and RUCM), unlike the BCM, are able to explain the coexistence of two stable final opinions, often observed in reality. Lastly, we present a mean field approximation of the newly introduced models.

  12. Behavioral Biases in Interpersonal Contexts

    NARCIS (Netherlands)

    N. Liu (Ning)

    2017-01-01

    markdownabstractThis thesis presents evidence suggesting that the same types of biases in individual decision making under uncertainty pertain in interpersonal contexts. The chapters above demonstrate in specific contexts how specific interpersonal factors attenuate, amplify, or replicate these bias

  13. Contextual modulation of biases in face recognition.

    Directory of Open Access Journals (Sweden)

    Fatima Maria Felisberti

    Full Text Available BACKGROUND: The ability to recognize the faces of potential cooperators and cheaters is fundamental to social exchanges, given that cooperation for mutual benefit is expected. Studies addressing biases in face recognition have so far proved inconclusive, with reports of biases towards faces of cheaters, biases towards faces of cooperators, or no biases at all. This study attempts to uncover possible causes underlying such discrepancies. METHODOLOGY AND FINDINGS: Four experiments were designed to investigate biases in face recognition during social exchanges when behavioral descriptors (prosocial, antisocial or neutral embedded in different scenarios were tagged to faces during memorization. Face recognition, measured as accuracy and response latency, was tested with modified yes-no, forced-choice and recall tasks (N = 174. An enhanced recognition of faces tagged with prosocial descriptors was observed when the encoding scenario involved financial transactions and the rules of the social contract were not explicit (experiments 1 and 2. Such bias was eliminated or attenuated by making participants explicitly aware of "cooperative", "cheating" and "neutral/indifferent" behaviors via a pre-test questionnaire and then adding such tags to behavioral descriptors (experiment 3. Further, in a social judgment scenario with descriptors of salient moral behaviors, recognition of antisocial and prosocial faces was similar, but significantly better than neutral faces (experiment 4. CONCLUSION: The results highlight the relevance of descriptors and scenarios of social exchange in face recognition, when the frequency of prosocial and antisocial individuals in a group is similar. Recognition biases towards prosocial faces emerged when descriptors did not state the rules of a social contract or the moral status of a behavior, and they point to the existence of broad and flexible cognitive abilities finely tuned to minor changes in social context.

  14. The Effect of State Anxiety on Paranoid Ideation and Jumping to Conclusions. An Experimental Investigation

    Science.gov (United States)

    Lincoln, Tania M.; Lange, Jennifer; Burau, Julia; Exner, Cornelia; Moritz, Steffen

    2010-01-01

    Theoretical models of persecutory delusions have emphasized the impact of reasoning biases and negative emotion at the early stages of symptom formation. However, the causal mechanisms remain unclear. This study tests the hypothesis that state anxiety will increase paranoid ideation and that this increase will be moderated by the level of individual vulnerability and mediated by the tendency to jump to conclusions. Healthy participants (n = 90) with varying levels of vulnerability (psychosis symptoms assessed by the Community Assessment of Psychic Experiences) were randomly assigned to either an anxiety or a nonanxiety condition. Anxiety was induced by pictures from the International Affective Picture System and by in sensu exposure to individual anxiety-provoking situations. During each condition, symptoms of paranoia were assessed by a state-adapted version of the Paranoia Checklist. Jumping to conclusions (JTC) was assessed using a modified version of the beads task. Overall, participants in the anxiety condition reported significantly more paranoid thoughts and showed more JTC than participants in the neutral condition. Participants with higher baseline vulnerability were more likely to show an increase in paranoia as reaction to the anxiety manipulation. Moreover, the association of anxiety and paranoia was mediated by the increased tendency to jump to conclusions in the beads task. The results are in line with a threat anticipation conceptualization of paranoia and provide evidence for an interaction of anxiety and reasoning biases in the development of paranoid beliefs. A combination of meta-cognitive training directed at reasoning biases and promoting emotion regulation skills might prove beneficial in preventing symptoms. PMID:19429844

  15. Assessing Bias in Search Engines.

    Science.gov (United States)

    Mowshowitz, Abbe; Kawaguchi, Akira

    2002-01-01

    Addresses the measurement of bias in search engines on the Web, defining bias as the balance and representation of items in a collection retrieved from a database for a set of queries. Assesses bias by measuring the deviation from the ideal of the distribution produced by a particular search engine. (Author/LRW)

  16. 19 CFR 111.68 - Proposed findings and conclusions.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Proposed findings and conclusions. 111.68 Section 111.68 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT... Monetary Penalty in Lieu of Suspension or Revocation § 111.68 Proposed findings and conclusions....

  17. Conflicts of interest in nutritional sciences: The forgotten bias in meta-analysis.

    Science.gov (United States)

    Lucas, Michel

    2015-12-26

    Awareness of conflicts of interest (COI) in medicine began in the 1980s. More recently, the problem has gained notoriety in nutritional sciences. COI with industry could bias study conclusions in the context of research activities and scientific publications on nutritional sciences. The issue of COI in nutritional sciences deserves more attention and requires careful analyses as biased information can negatively impact the development of dietary guidelines and, ultimately, population health. Decision-making is generally based on available, published evidence, but when the results are ambivalent, it is easier to opt for the status quo and ask for more studies. Readers might wonder if research is subsidized by industry as a counterbalancing strategy based on levels of evidence-only to slow down eminent positions and/or legislation on the food sector? How can this problem be overcome without producing paranoia and McCarthyism while trying to be as methodological as possible?

  18. The breadth and mnemonic consequences of the youth bias

    DEFF Research Database (Denmark)

    Koppel, Jonathan; Berntsen, Dorthe

    2016-01-01

    .e., deaths of public figures, US Presidential elections, and sporting events). We then investigated the possible role of the youth bias in structuring recall for public events, by probing, within-subjects, for the relation between: (1) These expectations of the timing, in a typical person’s life, of the most...

  19. Positioning of Weight Bias: Moving towards Social Justice

    Science.gov (United States)

    Alberga, Angela S.; Kassan, Anusha; Sesma-Vazquez, Monica

    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.

  20. Modeling Temporal Bias of Uplift Events in Recommender Systems

    KAUST Repository

    Altaf, Basmah

    2013-05-08

    Today, commercial industry spends huge amount of resources in advertisement campaigns, new marketing strategies, and promotional deals to introduce their product to public and attract a large number of customers. These massive investments by a company are worthwhile because marketing tactics greatly influence the consumer behavior. Alternatively, these advertising campaigns have a discernible impact on recommendation systems which tend to promote popular items by ranking them at the top, resulting in biased and unfair decision making and loss of customers’ trust. The biasing impact of popularity of items on recommendations, however, is not fixed, and varies with time. Therefore, it is important to build a bias-aware recommendation system that can rank or predict items based on their true merit at given time frame. This thesis proposes a framework that can model the temporal bias of individual items defined by their characteristic contents, and provides a simple process for bias correction. Bias correction is done either by cleaning the bias from historical training data that is used for building predictive model, or by ignoring the estimated bias from the predictions of a standard predictor. Evaluated on two real world datasets, NetFlix and MovieLens, our framework is shown to be able to estimate and remove the bias as a result of adopted marketing techniques from the predicted popularity of items at a given time.

  1. Positioning of Weight Bias: Moving towards Social Justice

    Directory of Open Access Journals (Sweden)

    Sarah Nutter

    2016-01-01

    Full Text Available 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.

  2. The breadth and mnemonic consequences of the youth bias

    DEFF Research Database (Denmark)

    Koppel, Jonathan; Berntsen, Dorthe

    2016-01-01

    .e., deaths of public figures, US Presidential elections, and sporting events). We then investigated the possible role of the youth bias in structuring recall for public events, by probing, within-subjects, for the relation between: (1) These expectations of the timing, in a typical person’s life, of the most...... question were correlated with the age at which the recalled event occurred, but only where particularly salient historical events did not play a central role in driving recall (i.e., for sporting events). We conclude that the youth bias holds across different types of public events and provides a default......We have recently demonstrated the existence of the youth bias, referring to a tendency to favor adolescence and early adulthood over other lifetime periods when making inferences about the timing of important public events across the lifespan of a typical individual within one’s culture. The youth...

  3. Bias aware Kalman filters

    DEFF Research Database (Denmark)

    Drecourt, J.-P.; Madsen, H.; Rosbjerg, Dan

    2006-01-01

    . 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....

  4. Writing to Climax: Strategies for Creating Effective Conclusions.

    Science.gov (United States)

    Brown, Stephen G.

    1996-01-01

    Provides pointers for incorporating the use of metaphors, alliteration, restating of the thesis, answering questions by reiteration of the thesis, and other ideas for writing an effective conclusion in high school and college papers. (PA)

  5. Systematic tests for position-dependent additive shear bias

    CERN Document Server

    van Uitert, Edo

    2016-01-01

    We present new tests to identify stationary position-dependent additive shear biases in weak gravitational lensing data sets. These tests are important diagnostics for currently ongoing and planned cosmic shear surveys, as such biases induce coherent shear patterns that can mimic and potentially bias the cosmic shear signal. The central idea of these tests is to determine the average ellipticity of all galaxies with shape measurements in a grid in the pixel plane. The distribution of the absolute values of these averaged ellipticities can be compared to randomized catalogues; a difference points to systematics in the data. In addition, we introduce a method to quantify the spatial correlation of the additive bias, which suppresses the contribution from cosmic shear and therefore eases the identification of a position-dependent additive shear bias in the data. We apply these tests to the publicly available shear catalogues from the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS) and the Kilo Degree Su...

  6. Weight bias against women in a university acceptance scenario.

    Science.gov (United States)

    Swami, Viren; Monk, Rachael

    2013-01-01

    This study examined weight bias against women in a hypothetical university acceptance scenario. One-hundred-and-ninety-eight volunteers from the community in Britain completed a weight bias measure in which they were asked to select the woman they were most and least likely to select for a place at university from an array of figures varying in body size. Participants also completed the Anti-Fat Attitudes Survey, the Short-Form of the Fat Phobia Scale, the Attitudes Toward Obese Persons Scale, and the Beliefs About Obese Persons Scale. Results showed that participants were biased against both obese (> 30 kg/m(2)) and emaciated (bias was only significantly predicted by greater antipathy toward fat persons and more negative attitudes toward obese persons. These results provide evidence that the general public hold biased beliefs about access to higher educational opportunities as a function of the body size of applicants.

  7. Gender Roles:Biases or Differences?

    Institute of Scientific and Technical Information of China (English)

    魏静

    2013-01-01

    This paper aims to probe into the two distinct gender roles-males and females-in several ways, and further answers the question“what on earth cause the salient differentiation in gender roles, biases or differences? ”In conclusion, the author holds that it is the physiological and psychological differences in the two sexes that result in the differed distribution of such vari-ous duties which males and females are supposed to fulfill as the current society has expected.

  8. Phototropin-dependent biased relocalization of cp-actin filaments can be induced even when chloroplast movement is inhibited.

    Science.gov (United States)

    Yamada, Noboru; Suetsugu, Noriyuki; Wada, Masamitsu; Kadota, Akeo

    2011-11-01

    In a recent publication using an actin-visualized line of Arabidopsis (Ichikawa et al. 2011, ref. 11), we reported a detailed analysis with higher time resolution on the dynamics of chloroplast actin filaments (cp-actin filaments) during chloroplast avoidance movement and demonstrated a good correlation between the biased configuration of cp-actin filaments and chloroplast movement. However, we could not conclusively determine whether the reorganization of cp-actin filaments into a biased configuration preceded actual chloroplast movement (and, thus, whether it could be a cause of the movement). In this report, we present clear evidence that the reorganization of cp-actin filaments into a biased distribution is induced even in the absence of the actual movement of chloroplasts. When the cells were treated with 2,3-butanedione monoxime (BDM), a potent inhibitor of myosin ATPase, chloroplast motility was completely suppressed. Nevertheless, the disappearance and biased relocalization of cp-actin filaments toward the side of the prospective movement direction were induced by irradiation with a strong blue light microbeam. The results definitively indicate that the reorganization of cp-actin filaments is not an effect of chloroplast movement; however, it is feasible that the biased localization of cp-actin filaments is an event leading to chloroplast movement.

  9. Outcome predictability biases learning.

    Science.gov (United States)

    Griffiths, Oren; Mitchell, Chris J; Bethmont, Anna; Lovibond, Peter F

    2015-01-01

    Much of contemporary associative learning research is focused on understanding how and when the associative history of cues affects later learning about those cues. Very little work has investigated the effects of the associative history of outcomes on human learning. Three experiments extended the "learned irrelevance" paradigm from the animal conditioning literature to examine the influence of an outcome's prior predictability on subsequent learning of relationships between cues and that outcome. All 3 experiments found evidence for the idea that learning is biased by the prior predictability of the outcome. Previously predictable outcomes were readily associated with novel predictive cues, whereas previously unpredictable outcomes were more readily associated with novel nonpredictive cues. This finding highlights the importance of considering the associative history of outcomes, as well as cues, when interpreting multistage designs. Associative and cognitive explanations of this certainty matching effect are discussed.

  10. The SDT Model of Belief Bias: Complexity, Time, and Cognitive Ability Mediate the Effects of Believability

    Science.gov (United States)

    Trippas, Dries; Handley, Simon J.; Verde, Michael F.

    2013-01-01

    When people evaluate conclusions, they are often influenced by prior beliefs. Prevalent theories claim that "belief bias" affects the quality of syllogistic reasoning. However, recent work by Dube, Rotello, and Heit (2010) has suggested that belief bias may be a simple response bias. In Experiment 1, receiver operating characteristic…

  11. Hypothesis, Prediction, and Conclusion: Using Nature of Science Terminology Correctly

    Science.gov (United States)

    Eastwell, Peter

    2012-01-01

    This paper defines the terms "hypothesis," "prediction," and "conclusion" and shows how to use the terms correctly in scientific investigations in both the school and science education research contexts. The scientific method, or hypothetico-deductive (HD) approach, is described and it is argued that an understanding of the scientific method,…

  12. 20 CFR 901.48 - Proposed findings and conclusions.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Proposed findings and conclusions. 901.48 Section 901.48 Employees' Benefits JOINT BOARD FOR THE ENROLLMENT OF ACTUARIES REGULATIONS GOVERNING THE PERFORMANCE OF ACTUARIAL SERVICES UNDER THE EMPLOYEE RETIREMENT INCOME SECURITY ACT OF 1974 Suspension...

  13. 22 CFR 18.18 - Proposed findings and conclusions.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Proposed findings and conclusions. 18.18 Section 18.18 Foreign Relations DEPARTMENT OF STATE PERSONNEL REGULATIONS CONCERNING POST EMPLOYMENT CONFLICT OF INTEREST Administrative Enforcement Proceedings § 18.18 Proposed findings and...

  14. Gender bias in scholarly peer review

    Science.gov (United States)

    Helmer, Markus; Schottdorf, Manuel; Neef, Andreas; Battaglia, Demian

    2017-01-01

    Peer review is the cornerstone of scholarly publishing and it is essential that peer reviewers are appointed on the basis of their expertise alone. However, it is difficult to check for any bias in the peer-review process because the identity of peer reviewers generally remains confidential. Here, using public information about the identities of 9000 editors and 43000 reviewers from the Frontiers series of journals, we show that women are underrepresented in the peer-review process, that editors of both genders operate with substantial same-gender preference (homophily), and that the mechanisms of this homophily are gender-dependent. We also show that homophily will persist even if numerical parity between genders is reached, highlighting the need for increased efforts to combat subtler forms of gender bias in scholarly publishing. DOI: http://dx.doi.org/10.7554/eLife.21718.001

  15. Gender bias in scholarly peer review.

    Science.gov (United States)

    Helmer, Markus; Schottdorf, Manuel; Neef, Andreas; Battaglia, Demian

    2017-03-21

    Peer review is the cornerstone of scholarly publishing and it is essential that peer reviewers are appointed on the basis of their expertise alone. However, it is difficult to check for any bias in the peer-review process because the identity of peer reviewers generally remains confidential. Here, using public information about the identities of 9000 editors and 43000 reviewers from the Frontiers series of journals, we show that women are underrepresented in the peer-review process, that editors of both genders operate with substantial same-gender preference (homophily), and that the mechanisms of this homophily are gender-dependent. We also show that homophily will persist even if numerical parity between genders is reached, highlighting the need for increased efforts to combat subtler forms of gender bias in scholarly publishing.

  16. Effect of an Intervention to Break the Gender Bias Habit for Faculty at One Institution: A Cluster Randomized, Controlled Trial

    Science.gov (United States)

    Carnes, Molly; Devine, Patricia G.; Manwell, Linda Baier; Byars-Winston, Angela; Fine, Eve; Ford, Cecilia E.; Forscher, Patrick; Isaac, Carol; Kaatz, Anna; Magua, Wairimu; Palta, Mari; Sheridan, Jennifer

    2014-01-01

    Purpose Despite sincere commitment to egalitarian, meritocratic principles, subtle gender bias persists, constraining women’s opportunities for academic advancement. The authors implemented a pair-matched, single-blind, cluster-randomized, controlled study of a gender bias habit-changing intervention at a large public university. Method Participants were faculty in 92 departments or divisions at the University of Wisconsin-Madison. Between September 2010 and March 2012, experimental departments were offered a gender bias habit-changing intervention as a 2.5 hour workshop. Surveys measured gender bias awareness; motivation, self-efficacy, and outcome expectations to reduce bias; and gender equity action. A timed word categorization task measured implicit gender/leadership bias. Faculty completed a worklife survey before and after all experimental departments received the intervention. Control departments were offered workshops after data were collected. Results Linear mixed-effects models showed significantly greater changes post-intervention for faculty in experimental vs. control departments on several outcome measures, including self-efficacy to engage in gender equity promoting behaviors (P = .013). When ≥ 25% of a department’s faculty attended the workshop (26 of 46 departments), significant increases in self-reported action to promote gender equity occurred at 3 months (P = .007). Post-intervention, faculty in experimental departments expressed greater perceptions of fit (P = .024), valuing of their research (P = .019), and comfort in raising personal and professional conflicts (P = .025). Conclusions An intervention that facilitates intentional behavioral change can help faculty break the gender bias habit and change department climate in ways that should support the career advancement of women in academic medicine, science, and engineering. PMID:25374039

  17. Bias towards publishing positive results in orthopedic and general surgery: a patient safety issue?

    Directory of Open Access Journals (Sweden)

    Ziran Bruce H

    2007-11-01

    Full Text Available Abstract Background Research articles reporting positive findings in the fields of orthopedic and general surgery appear to be represented at a considerably higher prevalence in the peer-reviewed literature, compared to published studies on negative or neutral data. This "publication bias" may alter the balance of the available evidence-based literature and may affect patient safety in surgery by depriving important information from unpublished negative studies. Methods A comprehensive review of all published articles in a defined 7-year period was performed in 12 representative journals in the fields of orthopedic and general surgery. Every article published in all volumes of these journals between January 2000 and December 2006 was reviewed and rated by three investigators. Rating of articles was performed according to a uniform, standardized algorithm. All original articles were stratified into "positive", "negative" or "neutral", depending on the reported results. All non-original papers were excluded from analysis. Results A total of 30,197 publications were reviewed over a 7-year time-period. After excluding all non-original articles, a total of 16,397 original papers were included in the final analysis. Of these, 12,251 (74% articles were found to report positive findings, 2,709 (17% reported negative results, and 1,437 (9% were neutral. A similar publication pattern was found among all years and all journals analyzed. Altogether, 91% of all original papers reported significant data (positive or negative, whereas only 9% were neutral studies that did not report any significant findings. Conclusion There is a disproportionately high number of articles reporting positive results published in the surgical literature. A bias towards publishing positive data will systematically overestimate the clinical relevance of treatment effects by disregarding important information derived from unpublished negative studies. This "publication bias

  18. Theoretical investigation of exchange bias

    Institute of Scientific and Technical Information of China (English)

    Xiong Zhi-Jie; Wang Huai-Yu; Ding Ze-Jun

    2007-01-01

    The exchange bias of bilayer magnetic films consisting of ferromagnetic (FM) and antiferromagnetic (AFM) layers in an uncompensated case is studied by use of the many-body Green's function method of quantum statistical theory.The effects of the layer thickness and temperature and the interfacial coupling strength on the exchange bias HE are investigated. The dependence of the exchange bias HE on the FM layer thickness and temperature is qualitatively in agreement with experimental results. When temperature varies, both the coercivity HC and HE decrease with the temperature increasing. For each FM thickness, there exists a least AFM thickness in which the exchange bias occurs,which is called pinning thickness.

  19. EMU – Fiscal Challenges: Conclusions For the New EU Members.

    OpenAIRE

    2005-01-01

    The aim of the paper is to evaluate fiscal challenges which are facing the Economic and Monetary Union countries after four years of monetary union functioning. Then, the author formulates conclusions for accession countries which are planning to become members of the Economic and Monetary Unions in the near future. The first part of the paper deals with the criteria of fiscal stabilization within EMU, their significance and links to economic growth. On the one hand, these criteria limit poss...

  20. Do Economists Reach a Conclusion on Household and Municipal Recycling?

    OpenAIRE

    Matthew Gunter

    2007-01-01

    Do economists reach a conclusion on household and municipal recycling? I explore the policy judgments of published economists on recycling and find that there is no broad consensus. The mainstream recycling literature is dominated by a guided-market approach; taxes and subsidies are advocated to correct for market failures. There are two less popular but still significant approaches: a minimal government laissez faire approach and a command and control regulatory approach. Laissez faire econo...

  1. Review conclusions by Ernst and Canter regarding spinal manipulation refuted

    Directory of Open Access Journals (Sweden)

    Evans Roni

    2006-08-01

    Full Text Available Abstract In the April 2006 issue of the Journal of Royal Society of Medicine, Ernst and Canter authored a review of the most recent systematic reviews on the effectiveness of spinal manipulation for any condition. The authors concluded that, except for back pain, spinal manipulation is not an effective intervention for any condition and, because of potential side effects, cannot be recommended for use at all in clinical practice. Based on a critical appraisal of their review, the authors of this commentary seriously challenge the conclusions by Ernst and Canter, who did not adhere to standard systematic review methodology, thus threatening the validity of their conclusions. There was no systematic assessment of the literature pertaining to the hazards of manipulation, including comparison to other therapies. Hence, their claim that the risks of manipulation outweigh the benefits, and thus spinal manipulation cannot be recommended as treatment for any condition, was not supported by the data analyzed. Their conclusions are misleading and not based on evidence that allow discrediting of a large body of professionals using spinal manipulation.

  2. Big bad data: law, public health, and biomedical databases.

    Science.gov (United States)

    Hoffman, Sharona; Podgurski, Andy

    2013-03-01

    The accelerating adoption of electronic health record (EHR) systems will have far-reaching implications for public health research and surveillance, which in turn could lead to changes in public policy, statutes, and regulations. The public health benefits of EHR use can be significant. However, researchers and analysts who rely on EHR data must proceed with caution and understand the potential limitations of EHRs. Because of clinicians' workloads, poor user-interface design, and other factors, EHR data can be erroneous, miscoded, fragmented, and incomplete. In addition, public health findings can be tainted by the problems of selection bias, confounding bias, and measurement bias. These flaws may become all the more troubling and important in an era of electronic "big data," in which a massive amount of information is processed automatically, without human checks. Thus, we conclude the paper by outlining several regulatory and other interventions to address data analysis difficulties that could result in invalid conclusions and unsound public health policies. © 2013 American Society of Law, Medicine & Ethics, Inc.

  3. Jumping to the wrong conclusions? An investigation of the mechanisms of reasoning errors in delusions.

    Science.gov (United States)

    Jolley, Suzanne; Thompson, Claire; Hurley, James; Medin, Evelina; Butler, Lucy; Bebbington, Paul; Dunn, Graham; Freeman, Daniel; Fowler, David; Kuipers, Elizabeth; Garety, Philippa

    2014-10-30

    Understanding how people with delusions arrive at false conclusions is central to the refinement of cognitive behavioural interventions. Making hasty decisions based on limited data ('jumping to conclusions', JTC) is one potential causal mechanism, but reasoning errors may also result from other processes. In this study, we investigated the correlates of reasoning errors under differing task conditions in 204 participants with schizophrenia spectrum psychosis who completed three probabilistic reasoning tasks. Psychotic symptoms, affect, and IQ were also evaluated. We found that hasty decision makers were more likely to draw false conclusions, but only 37% of their reasoning errors were consistent with the limited data they had gathered. The remainder directly contradicted all the presented evidence. Reasoning errors showed task-dependent associations with IQ, affect, and psychotic symptoms. We conclude that limited data-gathering contributes to false conclusions but is not the only mechanism involved. Delusions may also be maintained by a tendency to disregard evidence. Low IQ and emotional biases may contribute to reasoning errors in more complex situations. Cognitive strategies to reduce reasoning errors should therefore extend beyond encouragement to gather more data, and incorporate interventions focused directly on these difficulties.

  4. The renewal of humanism in psychotherapy: summary and conclusion.

    Science.gov (United States)

    Schneider, Kirk J; Längle, Alfried

    2012-12-01

    This article summarizes and discusses the main themes to emerge from this special section on the renewal of humanism in psychotherapy. It is concluded that (1) despite some controversies, humanism is both a viable and growing influence among the leading specialty areas of psychotherapy; (2) humanism is a foundational element of effectiveness among these specialty areas; and (3) humanistic training is essential to the development of trainees in the aforementioned specialty areas. The implications of these findings for each of the specialty areas, for the profession of psychotherapy, and for the public at large are elaborated, concluding with a call for a reassessment of priorities in the research, practice, and training of standardized mental health delivery. (c) 2012 APA, all rights reserved.

  5. Conclusions from the Image Analysis of the VSOP Survey

    Science.gov (United States)

    Dodson, R.; Fomalont, E.; Wiik, K.

    2009-08-01

    In February 1997, the Japanese radio astronomy satellite HALCA was launched to provide the space-bourne element for the VLBI Space Observatory Programme (VSOP) mission. A significant fraction of the mission time was to be dedicated to the VSOP Survey of bright compact Active Galactic Nuclei (AGN) at 5 GHz, which was lead by ISAS. The VSOP Survey Sources are an unbiased dataset of 294 targets, of which 82% were successfully observed. These are now undergoing statistical analysis to tease out the characteristics of typical AGN sources. We present here the summary of the imaging and conclusions we have reached.

  6. Bias in the Mass Media.

    Science.gov (United States)

    Cirino, Robert

    Non-language elements of bias in mass media--such as images, sounds, tones of voices, inflection, and facial expressions--are invariably integrated with the choice of language. Further, they have an emotional impact that is often greater than that of language. It is essential that the teacher of English deal with this non-language bias since it is…

  7. Sequential biases in accumulating evidence

    Science.gov (United States)

    Huggins, Richard; Dogo, Samson Henry

    2015-01-01

    Whilst it is common in clinical trials to use the results of tests at one phase to decide whether to continue to the next phase and to subsequently design the next phase, we show that this can lead to biased results in evidence synthesis. Two new kinds of bias associated with accumulating evidence, termed ‘sequential decision bias’ and ‘sequential design bias’, are identified. Both kinds of bias are the result of making decisions on the usefulness of a new study, or its design, based on the previous studies. Sequential decision bias is determined by the correlation between the value of the current estimated effect and the probability of conducting an additional study. Sequential design bias arises from using the estimated value instead of the clinically relevant value of an effect in sample size calculations. We considered both the fixed‐effect and the random‐effects models of meta‐analysis and demonstrated analytically and by simulations that in both settings the problems due to sequential biases are apparent. According to our simulations, the sequential biases increase with increased heterogeneity. Minimisation of sequential biases arises as a new and important research area necessary for successful evidence‐based approaches to the development of science. © 2015 The Authors. Research Synthesis Methods Published by John Wiley & Sons Ltd. PMID:26626562

  8. Large-Scale Galaxy Bias

    CERN Document Server

    Desjacques, Vincent; Schmidt, Fabian

    2016-01-01

    This review presents a comprehensive overview of galaxy bias, that is, the statistical relation between the distribution of galaxies and matter. We focus on large scales where cosmic density fields are quasi-linear. On these scales, the clustering of galaxies can be described by a perturbative bias expansion, and the complicated physics of galaxy formation is absorbed by a finite set of coefficients of the expansion, called bias parameters. The review begins with a pedagogical proof of this very important result, which forms the basis of the rigorous perturbative description of galaxy clustering, under the assumptions of General Relativity and Gaussian, adiabatic initial conditions. Key components of the bias expansion are all leading local gravitational observables, which includes the matter density but also tidal fields and their time derivatives. We hence expand the definition of local bias to encompass all these contributions. This derivation is followed by a presentation of the peak-background split in i...

  9. Bias and Causation Models and Judgment for Valid Comparisons

    CERN Document Server

    Weisberg, Herbert I

    2010-01-01

    A one-of-a-kind resource on identifying and dealing with bias in statistical research on causal effects. Do cell phones cause cancer? Can a new curriculum increase student achievement? Determining what the real causes of such problems are, and how powerful their effects may be, are central issues in research across various fields of study. Some researchers are highly skeptical of drawing causal conclusions except in tightly controlled randomized experiments, while others discount the threats posed by different sources of bias, even in less rigorous observational studies. Bias and Causation pre

  10. Hemispheric biases and the control of visuospatial attention: an ERP study

    Directory of Open Access Journals (Sweden)

    Banich Marie T

    2005-08-01

    Full Text Available Abstract Background We examined whether individual differences in hemispheric utilization can interact with the intrinsic attentional biases of the cerebral hemispheres. Evidence suggests that the hemispheres have competing biases to direct attention contralaterally, with the left hemisphere (LH having a stronger bias than the right hemisphere. There is also evidence that individuals have characteristic biases to utilize one hemisphere more than the other for processing information, which can induce a bias to direct attention to contralateral space. We predicted that LH-biased individuals would display a strong rightward attentional bias, which would create difficulty in selectively attending to target stimuli in the left visual field (LVF as compared to right in the performance of a bilateral flanker task. Results Consistent with our hypothesis, flanker interference effects were found on the N2c event-related brain potential and error rate for LH-biased individuals in the Attend-LVF condition. The error rate effect was correlated with the degree of hemispheric utilization bias for the LH-Bias group. Conclusion We conclude that hemispheric utilization bias can enhance a hemisphere's contralateral attentional bias, at least for individuals with a LH utilization bias. Hemispheric utilization bias may play an important and largely unrecognized role in visuospatial attention.

  11. Non-Gaussianity and Excursion Set Theory: Halo Bias

    Energy Technology Data Exchange (ETDEWEB)

    Adshead, Peter [Enrico Fermi Institute, Univ. of Chicago, IL (United States); Baxter, Eric J. [Univ. of Chicago, Chicago, IL (United States); Dodelson, Scott [Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Lidz, Adam [Univ. of Pennsylvania, Philadelphia, PA (United States)

    2012-09-01

    We study the impact of primordial non-Gaussianity generated during inflation on the bias of halos using excursion set theory. We recapture the familiar result that the bias scales as $k^{-2}$ on large scales for local type non-Gaussianity but explicitly identify the approximations that go into this conclusion and the corrections to it. We solve the more complicated problem of non-spherical halos, for which the collapse threshold is scale dependent.

  12. Conclusive quantum steering with superconducting transition edge sensors

    CERN Document Server

    Smith, Devin H; de Almeida, Marcelo; Branciard, Cyril; Fedrizzi, Alessandro; Weinhold, Till J; Lita, Adriana; Calkins, Brice; Gerrits, Thomas; Nam, Sae Woo; White, Andrew G

    2011-01-01

    Quantum steering allows two parties to verify shared entanglement even if one measurement device is untrusted. A conclusive demonstration of steering through the violation of a steering inequality is of considerable fundamental interest and opens up applications in quantum communication. To date all experimental tests with single photon states have relied on post-selection, allowing untrusted devices to cheat by hiding unfavorable events in losses. Here we close this "detection loophole" by combining a highly efficient source of entangled photon pairs with superconducting transition edge sensors. We achieve an unprecedented $\\sim$62% conditional detection efficiency of entangled photons and violate a steering inequality with the minimal number of measurement settings by 48 standard deviations. Our results provide a clear path to practical applications of steering and to a photonic loophole-free Bell test.

  13. The European Food Consumption Validation Project: conclusions and recommendations

    DEFF Research Database (Denmark)

    de Boer, E. J.; Slimani, N.; van 't Veer, P.

    2011-01-01

    Background/Objectives: To outline and discuss the main results and conclusions of the European Food Consumption Validation (EFCOVAL) Project. Subjects/Methods: The EFCOVAL Project was carried out within the EU Sixth Framework Program by researchers in 11 EU countries. The activities focused on (1...... showed that two non-consecutive EPIC-Soft 24-HDRs are suitable to estimate the usual intake distributions of protein and potassium of European adult populations. The 2-day non-consecutive 24-HDRs in combination with a food propensity questionnaire also appeared to be appropriate to rank individuals...... according to their fish and fruit and vegetable intake in a comparable way in five European centers. Dietary intake of (young) children can be assessed by the combination of EPIC-Soft 24-HDRs and food recording booklets. The EPIC-Soft-standardized method of describing foods is useful to estimate dietary...

  14. Bias and ignorance in demographic perception.

    Science.gov (United States)

    Landy, D; Guay, B; Marghetis, T

    2017-08-31

    When it comes to knowledge of demographic facts, misinformation appears to be the norm. Americans massively overestimate the proportions of their fellow citizens who are immigrants, Muslim, LGBTQ, and Latino, but underestimate those who are White or Christian. Previous explanations of these estimation errors have invoked topic-specific mechanisms such as xenophobia or media bias. We reconsidered this pattern of errors in the light of more than 30 years of research on the psychological processes involved in proportion estimation and decision-making under uncertainty. In two publicly available datasets featuring demographic estimates from 14 countries, we found that proportion estimates of national demographics correspond closely to what is found in laboratory studies of quantitative estimates more generally. Biases in demographic estimation, therefore, are part of a very general pattern of human psychology-independent of the particular topic or demographic under consideration-that explains most of the error in estimates of the size of politically salient populations. By situating demographic estimates within a broader understanding of general quantity estimation, these results demand reevaluation of both topic-specific misinformation about demographic facts and topic-specific explanations of demographic ignorance, such as media bias and xenophobia.

  15. Assembly bias and splashback in galaxy clusters

    Science.gov (United States)

    Busch, Philipp; White, Simon D. M.

    2017-10-01

    We use publicly available data for the Millennium Simulation to explore the implications of the recent detection of assembly bias and splashback signatures in a large sample of galaxy clusters. These were identified in the Sloan Digital Sky Survey/Data Release 8 (SDSS/DR8) photometric data by the redMaPPer algorithm and split into high- and low-concentration subsamples based on the projected positions of cluster members. We use simplified versions of these procedures to build cluster samples of similar size from the simulation data. These match the observed samples quite well and show similar assembly bias and splashback signals. Previous theoretical work has found the logarithmic slope of halo density profiles to have a well-defined minimum whose depth decreases and whose radius increases with halo concentration. Projected profiles for the observed and simulated cluster samples show trends with concentration which are opposite to these predictions. In addition, for high-concentration clusters the minimum slope occurs at significantly smaller radius than predicted. We show that these discrepancies all reflect confusion between splashback features and features imposed on the profiles by the cluster identification and concentration estimation procedures. The strong apparent assembly bias is not reflected in the three-dimensional distribution of matter around clusters. Rather it is a consequence of the preferential contamination of low-concentration clusters by foreground or background groups.

  16. Risk of bias in research in oral and maxillofacial surgery.

    Science.gov (United States)

    Oomens, M A E M; Heymans, M W; Forouzanfar, T

    2013-12-01

    The risk of bias is important in the interpretation of the results of research. The aim of this review was to evaluate the risk of bias in randomised controlled trials (RCTs) in oral and maxillofacial surgery (OMFS) over a 10-year period. We searched databases of publications for RCTs published between January 2000 and January 2010. Papers were assessed with 2 up-to-date logical quality lists, the Delphi list and the Jadad scale. Those papers with a low risk of bias were given a Jadad score ≥4 (range 0-5) and a Delphi score ≥6 (range 0-9). A total of 230 papers met the inclusion criteria, and only 41 (18%) were assessed as being at low risk. Most of those included did not correctly describe such important items for risk of bias as method of randomisation (n=124, 54%), concealment of allocation (n=143, 62%), blinding (n=175, 76%), and intention-to-treat analyses (n=182, 79%). In the fields of implantology, traumatology, obstructive sleep apnoea syndrome, and extractions, no paper had a low risk of bias. This systematic review has shown a shortage of research in OMFS with a low risk of bias published over a 10-year period. Further research should concentrate on better describing items at important risk of bias.

  17. 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.

  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. 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.

  20. Employee counseling services evaluation system: design, issues and conclusions.

    Science.gov (United States)

    Masi, D A; Teems, L A

    1983-01-01

    Employee Counseling Services (ECS) programs have emerged as an effective method for dealing with employees whose job performance has deteriorated due to personal problems such as alcoholism or drug abuse. It is estimated that 18% of any work force is effected by such problems at any given time and that these employees cost industry billions of dollars annually in lost productivity, abuse of sick leave, etc. One of the critical concerns of this emerging field is the need for comprehensive evaluation that can demonstrate the cost-effectiveness and cost-benefits of ECS programs. This paper will describe the model Federal ECS developed at the U.S. Department of Health and Human Services as well as the components of the evaluation system designed to determine its effectiveness. The system is the first of its kind and will be a valuable contribution to the field. The paper then raises issues and develops conclusions about designing such an evaluation within the context of a large bureaucracy.

  1. Bionics in Engineering Education Considerations, Experiences and Conclusions

    Directory of Open Access Journals (Sweden)

    Ralf Neurohr

    2008-01-01

    Full Text Available During recent years bionics, a new discipline which is in charge with the transfer of the principles of construction, regulation, interaction and organisation of biology into innovative technical solutions, has attracted significant interest from various industries. Based on this request for bionic expertise in engineering, the faculty for teaching engineering in foreign languages (FILS at ‘Politehnica’ University of Bucharest started a course in bionics in SS 2007, which was supported by the expertise of the German ‘Bionik-Kompetenz-Netz’, one of the leading organizations in bionics. This is the report on the considerations involved in the course concept, the first experiences with the students' acceptance, some conclusions and future perspectives for extending bionics activities at ‘Politehnica’. Finally, within the last section, the evaluation of a questionnaire, filled in by the students at the end of the course, will be presented. In order to avoid any confusion, considering overlapping or mixing up with other bio-disciplines related to technology, the paper starts with a short introduction, explaining the principles of bionics and providing a clear definition of the field.

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

    OpenAIRE

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

    2017-01-01

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

  3. FractBias: a graphical tool for assessing fractionation bias following polyploidy.

    Science.gov (United States)

    Joyce, Blake L; Haug-Baltzell, Asher; Davey, Sean; Bomhoff, Matthew; Schnable, James C; Lyons, Eric

    2017-02-15

    Following polyploidy events, genomes undergo massive reduction in gene content through a process known as fractionation. Importantly, the fractionation process is not always random, and a bias as to which homeologous chromosome retains or loses more genes can be observed in some species. The process of characterizing whole genome fractionation requires identifying syntenic regions across genomes followed by post-processing of those syntenic datasets to identify and plot gene retention patterns. We have developed a tool, FractBias, to calculate and visualize gene retention and fractionation patterns across whole genomes. Through integration with SynMap and its parent platform CoGe, assembled genomes are pre-loaded and available for analysis, as well as letting researchers integrate their own data with security options to keep them private or make them publicly available. FractBias is freely available as a web application at https://genomevolution.org/CoGe/SynMap.pl . The software is open source (MIT license) and executable with Python 2.7 or iPython notebook, and available on GitHub ( https://goo.gl/PaAtqy ). Documentation for FractBias is available on CoGepedia ( https://goo.gl/ou9dt6 ). ericlyons@email.arizona.edu. Supplementary data are available at Bioinformatics online.

  4. Optimal classifier selection and negative bias in error rate estimation: an empirical study on high-dimensional prediction

    Directory of Open Access Journals (Sweden)

    Boulesteix Anne-Laure

    2009-12-01

    Full Text Available Abstract Background In biometric practice, researchers often apply a large number of different methods in a "trial-and-error" strategy to get as much as possible out of their data and, due to publication pressure or pressure from the consulting customer, present only the most favorable results. This strategy may induce a substantial optimistic bias in prediction error estimation, which is quantitatively assessed in the present manuscript. The focus of our work is on class prediction based on high-dimensional data (e.g. microarray data, since such analyses are particularly exposed to this kind of bias. Methods In our study we consider a total of 124 variants of classifiers (possibly including variable selection or tuning steps within a cross-validation evaluation scheme. The classifiers are applied to original and modified real microarray data sets, some of which are obtained by randomly permuting the class labels to mimic non-informative predictors while preserving their correlation structure. Results We assess the minimal misclassification rate over the different variants of classifiers in order to quantify the bias arising when the optimal classifier is selected a posteriori in a data-driven manner. The bias resulting from the parameter tuning (including gene selection parameters as a special case and the bias resulting from the choice of the classification method are examined both separately and jointly. Conclusions The median minimal error rate over the investigated classifiers was as low as 31% and 41% based on permuted uninformative predictors from studies on colon cancer and prostate cancer, respectively. We conclude that the strategy to present only the optimal result is not acceptable because it yields a substantial bias in error rate estimation, and suggest alternative approaches for properly reporting classification accuracy.

  5. Anterior Chamber Contamination at the Conclusion of Phacoemulsification

    Directory of Open Access Journals (Sweden)

    Mohammad-Reza Soleimani

    2008-12-01

    Full Text Available

    PURPOSE: To evaluate anterior chamber aspirates at the conclusion of phacoemulsification and intraocular lens implantation (PE+IOL for bacterial and fungal contamination. METHODS: We prospectively evaluated 80 eyes of 80 patients undergoing routine PE+IOL by performing bacterial and fungal culture on aspirates obtained from the anterior chamber at the end of the surgery. RESULTS: Anterior chamber fluid aspirates were positive for bacteria in 5 eyes (6.33% with coagulase-negative staphylococcus being the most common organism (three eyes. No instance of positive fungus culture was observed. One of the culture-positive eyes developed postoperative uveitis which resolved during a week of treatment with topical corticosteroids and antibiotics.  None of the eyes developed endophthalmitis. CONCLUSION: In the current series, the rate of anterior chamber contamination by bacteria at the end of phacoemulsification was in the lower range reported by previous studies.  

  1. Publicity and public relations

    Science.gov (United States)

    Fosha, Charles E.

    1990-01-01

    This paper addresses approaches to using publicity and public relations to meet the goals of the NASA Space Grant College. Methods universities and colleges can use to publicize space activities are presented.

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

    Directory of Open Access Journals (Sweden)

    John M McPartland

    Full Text Available BACKGROUND: 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. METHODS/PRINCIPAL FINDINGS: 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. CONCLUSIONS: 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.

  3. Trial Registration: Understanding and Preventing Reporting Bias in Social Work Research

    Science.gov (United States)

    Harrison, Bronwyn A.; Mayo-Wilson, Evan

    2014-01-01

    Randomized controlled trials are considered the gold standard for evaluating social work interventions. However, published reports can systematically overestimate intervention effects when researchers selectively report large and significant findings. Publication bias and other types of reporting biases can be minimized through prospective trial…

  4. Epistemological and ethical assessment of obesity bias in industrialized countries

    Directory of Open Access Journals (Sweden)

    Azétsop Jacquineau

    2011-12-01

    Full Text Available Abstract Bernard Lonergan's cognitive theory challenges us to raise questions about both the cognitive process through which obesity is perceived as a behaviour change issue and the objectivity of such a moral judgment. Lonergan's theory provides the theoretical tools to affirm that anti-fat discrimination, in the United States of America and in many industrialized countries, is the result of both a group bias that resists insights into the good of other groups and a general bias of anti-intellectualism that tends to set common sense against insights that require any thorough scientific analyses. While general bias diverts the public's attention away from the true aetiology of obesity, group bias sustains an anti-fat culture that subtly legitimates discriminatory practices and policies against obese people. Although anti-discrimination laws may seem to be a reasonable way of protecting obese and overweight individuals from discrimination, obesity bias can be best addressed by reframing the obesity debate from an environmental perspective from which tools and strategies to address both the social and individual determinants of obesity can be developed. Attention should not be concentrated on individuals' behaviour as it is related to lifestyle choices, without giving due consideration to the all-encompassing constraining factors which challenge the social and rational blindness of obesity bias.

  5. Is there bias in the current recommendations for influenza vaccine?

    Directory of Open Access Journals (Sweden)

    Gonzalo Alvear Téllez

    2013-11-01

    Full Text Available Context. Influenza vaccine has been aggressively promoted and is currently recommended to practically the whole population, especially in some European Union countries and in the United States of America. Is there sound evidence to support this policy recommendation? Is this disease so serious and aggressive to merit the enormous expenditure associated with mass immunization? Aim. The article seeks to analyze the published evidence that supports the practically generalized recommendation of universal immunization for influenza. Analysis. The analysis of the evidence invoked to support this recommendation of mass flu vaccine shows that there are multiple types of bias present. Likewise, the evidence shows that the vaccine only has effects on flu symptoms. Conversely, adverse effects to the flu vaccine have been reported in Australia (febrile seizures in 1/110, Canada (people who got the flu shot in 2008 had increased risk of contracting H1N1 pandemic influenza in 2009, Sweden and Finland (one case of narcolepsy in 55,000. Conclusion. There is no solid evidence showing that influenza is a threat to public health, nor that the flu shot in any way reduces influenza complications and mortality.

  6. Public Health and Social Desirability in Kazakhstan: Methodological Considerations

    Directory of Open Access Journals (Sweden)

    Brett J. Craig

    2016-03-01

    Conclusions: Participant reports regarding personal health behaviors and lifestyle did not reflect the national reports regarding lifestyle behaviors. The relationship between powerful others subscale and tobacco smoking indicate that using healthcare providers may open up avenues to lowering tobacco use through patient education; however, social desirability is a notable concern for public health interventions. More importantly, the surveys uncovered future questions for conducting public health research with the general public, including issues of trust in the healthcare system and social desirability bias. Additional factors such as distrust in healthcare and government also may play a role in the public’s participation in social scientific research. The students who conducted the surveys reported a general skepticism from the public ranging from unfamiliarity with survey research to explicit distrust in the intentions and purpose of the research itself.

  7. Gender bias in academic recruitment

    DEFF Research Database (Denmark)

    Abramo, Giovanni; D’Angelo, Ciriaco Andrea; Rosati, Francesco

    2016-01-01

    It is well known that women are underrepresented in the academic systems of many countries. Gender discrimination is one of the factors that could contribute to this phenomenon. This study considers a recent national academic recruitment campaign in Italy, examining whether women are subject...... to more or less bias than men. The findings show that no gender-related differences occur among the candidates who benefit from positive bias, while among those candidates affected by negative bias, the incidence of women is lower than that of men. Among the factors that determine success in a competition...... for an academic position, the number of the applicant’s career years in the same university as the committee members assumes greater weight for male candidates than for females. Being of the same gender as the committee president is also a factor that assumes greater weight for male applicants. On the other hand...

  8. Anchoring Bias in Online Voting

    CERN Document Server

    Yang, Zimo; Zhou, Tao

    2012-01-01

    Voting online with explicit ratings could largely reflect people's preferences and objects' qualities, but ratings are always irrational, because they may be affected by many unpredictable factors like mood, weather, as well as other people's votes. By analyzing two real systems, this paper reveals a systematic bias embedding in the individual decision-making processes, namely people tend to give a low rating after a low rating, as well as a high rating following a high rating. This so-called \\emph{anchoring bias} is validated via extensive comparisons with null models, and numerically speaking, the extent of bias decays with interval voting number in a logarithmic form. Our findings could be applied in the design of recommender systems and considered as important complementary materials to previous knowledge about anchoring effects on financial trades, performance judgements, auctions, and so on.

  9. Without Bias: A Guidebook for Nondiscriminatory Communication.

    Science.gov (United States)

    Pickens, Judy E., Ed.; And Others

    This guidebook discusses ways to eliminate various types of discrimination from business communications. Separately authored chapters discuss eliminating racial and ethnic bias; eliminating sexual bias; achieving communication sensitive about handicaps of disabled persons; eliminating bias from visual media; eliminating bias from meetings,…

  10. The Truth and Bias Model of Judgment

    Science.gov (United States)

    West, Tessa V.; Kenny, David A.

    2011-01-01

    We present a new model for the general study of how the truth and biases affect human judgment. In the truth and bias model, judgments about the world are pulled by 2 primary forces, the truth force and the bias force, and these 2 forces are interrelated. The truth and bias model differentiates force and value, where the force is the strength of…

  11. The Truth and Bias Model of Judgment

    Science.gov (United States)

    West, Tessa V.; Kenny, David A.

    2011-01-01

    We present a new model for the general study of how the truth and biases affect human judgment. In the truth and bias model, judgments about the world are pulled by 2 primary forces, the truth force and the bias force, and these 2 forces are interrelated. The truth and bias model differentiates force and value, where the force is the strength of…

  12. Unpacking the Evidence of Gender Bias

    Science.gov (United States)

    Fulmer, Connie L.

    2010-01-01

    The purpose of this study was to investigate gender bias in pre-service principals using the Gender-Leader Implicit Association Test. Analyses of student-learning narratives revealed how students made sense of gender bias (biased or not-biased) and how each reacted to evidence (surprised or not-surprised). Two implications were: (1) the need for…

  13. Measurement Bias Detection through Factor Analysis

    Science.gov (United States)

    Barendse, M. T.; Oort, F. J.; Werner, C. S.; Ligtvoet, R.; Schermelleh-Engel, K.

    2012-01-01

    Measurement bias is defined as a violation of measurement invariance, which can be investigated through multigroup factor analysis (MGFA), by testing across-group differences in intercepts (uniform bias) and factor loadings (nonuniform bias). Restricted factor analysis (RFA) can also be used to detect measurement bias. To also enable nonuniform…

  14. Codon Pair Bias Is a Direct Consequence of Dinucleotide Bias

    Directory of Open Access Journals (Sweden)

    Dusan Kunec

    2016-01-01

    Full Text Available Codon pair bias is a remarkably stable characteristic of a species. Although functionally uncharacterized, robust virus attenuation was achieved by recoding of viral proteins using underrepresented codon pairs. Because viruses replicate exclusively inside living cells, we posited that their codon pair preferences reflect those of their host(s. Analysis of many human viruses showed, however, that the encoding of viruses is influenced only marginally by host codon pair preferences. Furthermore, examination of codon pair preferences of vertebrate, insect, and arthropod-borne viruses revealed that the latter do not utilize codon pairs overrepresented in arthropods more frequently than other viruses. We found, however, that codon pair bias is a direct consequence of dinucleotide bias. We conclude that codon pair bias does not play a major role in the encoding of viral proteins and that virus attenuation by codon pair deoptimization has the same molecular underpinnings as attenuation based on an increase in CpG/TpA dinucleotides.

  15. The Threshold of Embedded M Collider Bias and Confounding Bias

    Science.gov (United States)

    Kelcey, Benjamin; Carlisle, Joanne

    2011-01-01

    Of particular import to this study, is collider bias originating from stratification on retreatment variables forming an embedded M or bowtie structural design. That is, rather than assume an M structural design which suggests that "X" is a collider but not a confounder, the authors adopt what they consider to be a more reasonable…

  16. View of Mission Control Center celebrating conclusion of Apollo 11 mission

    Science.gov (United States)

    1969-01-01

    Overall view of the Mission Operations Control Room in the Mission Control Center, bldg 30, Manned Spacecraft Center (MSC), at the conclusion of the Apollo 11 lunar landing mission. The television monitor shows President Richard M. Nixon greeting the Apollo 11 astronauts aboard the U.S.S. Hornet in the Pacific recovery area (40301); NASA and MSC Officials join the flight controllers in celebrating the conclusion of the Apollo 11 mission. From left foreground Dr. Maxime A. Faget, MSC Director of Engineering and Development; George S. Trimble, MSC Deputy Director; Dr. Christopher C. Kraft Jr., MSC Director fo Flight Operations; Julian Scheer (in back), Assistant Adminstrator, Offic of Public Affairs, NASA HQ.; George M. Low, Manager, Apollo Spacecraft Program, MSC; Dr. Robert R. Gilruth, MSC Director; and Charles W. Mathews, Deputy Associate Administrator, Office of Manned Space Flight, NASA HQ (40302).

  17. Can decision biases improve insurance outcomes? An experiment on status quo bias in health insurance choice.

    Science.gov (United States)

    Krieger, Miriam; Felder, Stefan

    2013-06-19

    Rather than conforming to the assumption of perfect rationality in neoclassical economic theory, decision behavior has been shown to display a host of systematic biases. Properly understood, these patterns can be instrumentalized to improve outcomes in the public realm. We conducted a laboratory experiment to study whether decisions over health insurance policies are subject to status quo bias and, if so, whether experience mitigates this framing effect. Choices in two treatment groups with status quo defaults are compared to choices in a neutrally framed control group. A two-step design features sorting of subjects into the groups, allowing us to control for selection effects due to risk preferences. The results confirm the presence of a status quo bias in consumer choices over health insurance policies. However, this effect of the default framing does not persist as subjects repeat this decision in later periods of the experiment. Our results have implications for health care policy, for example suggesting that the use of non-binding defaults in health insurance can facilitate the spread of co-insurance policies and thereby help contain health care expenditure.

  18. Effects of Cognitive Bias Modification Training via Smartphones

    Directory of Open Access Journals (Sweden)

    Ranming Yang

    2017-08-01

    Full Text Available Background and Objectives: Negative cognitive biases have been linked to anxiety and mood problems. Accumulated data from laboratory studies show that positive and negative interpretation styles with accompanying changes in mood can be induced through cognitive bias modification (CBM paradigms. Despite the therapeutic potential of positive training effects, few studies have explored training paradigms administered via smartphones. The current study aimed to compare the effectiveness of three different types of training programmes (cognitive bias modification-attention, CBM-A; cognitive bias modification-interpretation, CBM-I; attention and interpretation modification, AIM administered via smart-phones by using a control condition (CC.Methods:Seventy-six undergraduate participants with high social anxiety (Liebowitz Social Anxiety Scale, LSAS ≥ 30 were randomly assigned to four groups: CBM-A (n = 20, CBM-I (n = 20, AIM (n = 16, and CC (n = 20.Results: The results showed that the effects of CBM training, CBM-I training, or AIM training vs. CC for attention yielded no significant differences in dot-probe attention bias scores. The CBM-I group showed significantly less threat interpretation and more benign interpretation than the CC group on interpretation bias scores.Conclusions: The present results supported the feasibility of delivering CBM-I via smartphones, but the effectiveness of CBM-A and AIM training via smartphones was limited.

  19. Bias in Dynamic Monte Carlo Alpha Calculations

    Energy Technology Data Exchange (ETDEWEB)

    Sweezy, Jeremy Ed [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Nolen, Steven Douglas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Adams, Terry R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Trahan, Travis John [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-02-06

    A 1/N bias in the estimate of the neutron time-constant (commonly denoted as α) has been seen in dynamic neutronic calculations performed with MCATK. In this paper we show that the bias is most likely caused by taking the logarithm of a stochastic quantity. We also investigate the known bias due to the particle population control method used in MCATK. We conclude that this bias due to the particle population control method is negligible compared to other sources of bias.

  20. Pressure Measurement Techniques for Abdominal Hypertension: Conclusions from an Experimental Model

    Directory of Open Access Journals (Sweden)

    Sascha Santosh Chopra

    2015-01-01

    Full Text Available Introduction. Intra-abdominal pressure (IAP measurement is an indispensable tool for the diagnosis of abdominal hypertension. Different techniques have been described in the literature and applied in the clinical setting. Methods. A porcine model was created to simulate an abdominal compartment syndrome ranging from baseline IAP to 30 mmHg. Three different measurement techniques were applied, comprising telemetric piezoresistive probes at two different sites (epigastric and pelvic for direct pressure measurement and intragastric and intravesical probes for indirect measurement. Results. The mean difference between the invasive IAP measurements using telemetric pressure probes and the IVP measurements was −0.58 mmHg. The bias between the invasive IAP measurements and the IGP measurements was 3.8 mmHg. Compared to the realistic results of the intraperitoneal and intravesical measurements, the intragastric data showed a strong tendency towards decreased values. The hydrostatic character of the IAP was eliminated at high-pressure levels. Conclusion. We conclude that intragastric pressure measurement is potentially hazardous and might lead to inaccurately low intra-abdominal pressure values. This may result in missed diagnosis of elevated abdominal pressure or even ACS. The intravesical measurements showed the most accurate values during baseline pressure and both high-pressure plateaus.

  1. Correspondences between theory of mind, jumping to conclusions, neuropsychological measures and the symptoms of schizophrenia.

    Science.gov (United States)

    Woodward, Todd S; Mizrahi, Romina; Menon, Mahesh; Christensen, Bruce K

    2009-12-30

    Tasks measuring reasoning biases and social cognition were originally applied to the study of schizophrenia in order to shed light on the cognitive underpinnings of positive symptoms. However, the empirical evidence for overlap between these tasks, and their association with positive symptoms, remains preliminary. In the current study we explore these associations using multivariate methodology, with primary interest in two commonly studied paradigms: jumping to conclusions (JTC) and theory of mind (ToM). We also included measures of memory, executive function and fluency performance, in order to relate the cognitive constructs to more traditional neuropsychological constructs. Forty-six schizophrenia inpatients were administered JTC, ToM, verbal fluency, executive functioning, and verbal memory tasks. A principal component analysis resulted in three components interpreted as Memory, Elaboration and Flexibility. ToM loaded with verbal fluency on the Elaboration component, whereas JTC loaded with executive functioning on the Flexibility component. The negative susbscale of the Positive and Negative Syndrome Scale (PANSS) correlated with the Elaboration component, but no other component-subscale correlations reached significance. Implications of these results are that impairments in elaboration may underlie the commonly observed correlation between ToM and negative symptoms, but argue against a common neurocognitive system for JTC, ToM and positive symptoms.

  2. Publication bias and the canonization of false facts

    DEFF Research Database (Denmark)

    Nissen, Silas Boye; Magidson, Tali; Gross, Kevin;

    2016-01-01

    canonized as fact. Data-dredging, p-hacking, and similar behaviors exacerbate the problem. Should negative results become easier to publish as a claim approaches acceptance as a fact, however, true and false claims would be more readily distinguished. To the degree that the model reflects the real world...

  3. Publication bias- a reason for the decreased research output in ...

    African Journals Online (AJOL)

    Adele

    countries in high impact psychiatric journals.1 Some of the ... of manpower, funding, scientific knowledge and skill in ... Department of Psychiatry, Nelson R Mandela School of Medicine, University of Kwa-Zulu Natal, Durban, South ... become more innovative and include the changing paradigm in epidemiological research.

  4. Publication bias and the canonization of false facts

    DEFF Research Database (Denmark)

    Nissen, Silas Boye; Magidson, Tali; Gross, Kevin

    2016-01-01

    Science is facing a "replication crisis" in which many experimental findings cannot be replicated and are likely to be false. Does this imply that many scientific facts are false as well? To find out, we explore the process by which a claim becomes fact. We model the community's confidence...

  5. Ratio Bias and Policy Preferences

    DEFF Research Database (Denmark)

    Pedersen, Rasmus Tue

    2016-01-01

    Numbers permeate modern political communication. While current scholarship on framing effects has focused on the persuasive effects of words and arguments, this article shows that framing of numbers can also substantially affect policy preferences. Such effects are caused by ratio bias, which is ...

  6. Perception bias in route choice

    NARCIS (Netherlands)

    Vreeswijk, Jacob Dirk; Thomas, Tom; van Berkum, Eric C.; van Arem, Bart

    2014-01-01

    Travel time is probably one of the most studied attributes in route choice. Recently, perception of travel time received more attention as several studies have shown its importance in explaining route choice behavior. In particular, travel time estimates by travelers appear to be biased against

  7. Perception bias in route choice

    NARCIS (Netherlands)

    Vreeswijk, Jacob Dirk; Thomas, Tom; van Berkum, Eric C.; van Arem, Bart

    2014-01-01

    Travel time is probably one of the most studied attributes in route choice. Recently, perception of travel time received more attention as several studies have shown its importance in explaining route choice behavior. In particular, travel time estimates by travelers appear to be biased against non-

  8. Attentional bias in math anxiety

    Science.gov (United States)

    Rubinsten, Orly; Eidlin, Hili; Wohl, Hadas; Akibli, Orly

    2015-01-01

    Cognitive theory from the field of general anxiety suggests that the tendency to display attentional bias toward negative information results in anxiety. Accordingly, the current study aims to investigate whether attentional bias is involved in math anxiety (MA) as well (i.e., a persistent negative reaction to math). Twenty seven participants (14 with high levels of MA and 13 with low levels of MA) were presented with a novel computerized numerical version of the well established dot probe task. One of six types of prime stimuli, either math related or typically neutral, was presented on one side of a computer screen. The prime was preceded by a probe (either one or two asterisks) that appeared in either the prime or the opposite location. Participants had to discriminate probe identity (one or two asterisks). Math anxious individuals reacted faster when the probe was at the location of the numerical related stimuli. This suggests the existence of attentional bias in MA. That is, for math anxious individuals, the cognitive system selectively favored the processing of emotionally negative information (i.e., math related words). These findings suggest that attentional bias is linked to unduly intense MA symptoms. PMID:26528208

  9. Attentional Bias in Math Anxiety

    Directory of Open Access Journals (Sweden)

    Orly eRubinsten

    2015-10-01

    Full Text Available Cognitive theory from the field of general anxiety suggests that the tendency to display attentional bias toward negative information results in anxiety. Accordingly, the current study aims to investigate whether attentional bias is involved in math anxiety as well (i.e., a persistent negative reaction to math. Twenty seven participants (14 with high levels of math anxiety and 13 with low levels of math anxiety were presented with a novel computerized numerical version of the well established dot probe task. One of 6 types of prime stimuli, either math related or typically neutral, were presented on one side of a computer screen. The prime was preceded by a probe (either one or two asterisks that appeared in either the prime or the opposite location. Participants had to discriminate probe identity (one or two asterisks. Math anxious individuals reacted faster when the probe was at the location of the numerical related stimuli. This suggests the existence of attentional bias in math anxiety. That is, for math anxious individuals, the cognitive system selectively favored the processing of emotionally negative information (i.e., math related words. These findings suggest that attentional bias is linked to unduly intense math anxiety symptoms.

  10. Stereotype Formation : Biased by Association

    NARCIS (Netherlands)

    Le Pelley, Mike E.; Reimers, Stian J.; Calvini, Guglielmo; Spears, Russell; Beesley, Tom; Murphy, Robin A.

    2010-01-01

    We propose that biases in attitude and stereotype formation might arise as a result of learned differences ill the extent its which social groups have previously been predictive elf behavioral or physical properties Experiments 1 and 2 demonstrate that differences in the experienced predictiveness o

  11. Sex Bias in Counseling Materials

    Science.gov (United States)

    Harway, Michele

    1977-01-01

    This article reviews findings of bias in counseling materials and presents results of three original studies. Indications are that textbooks used by practitioners present the sexes in stereotypical fashion, and a greater proportion of college catalog context is devoted to men than to women. (Author)

  12. Perception bias in route choice

    NARCIS (Netherlands)

    Vreeswijk, J.D.; Thomas, T.; Berkum, van E.C.; Arem, van B.

    2014-01-01

    Travel time is probably one of the most studied attributes in route choice. Recently, perception of travel time received more attention as several studies have shown its importance in explaining route choice behavior. In particular, travel time estimates by travelers appear to be biased against non-

  13. Measurement Bias in Multilevel Data

    NARCIS (Netherlands)

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

    2014-01-01

    Measurement bias can be detected using structural equation modeling (SEM), by testing measurement invariance with multigroup factor analysis (Jöreskog, 1971;Meredith, 1993;Sörbom, 1974) MIMIC modeling (Muthén, 1989) or restricted factor analysis (Oort, 1992,1998). In educational research, data often

  14. Measurement bias in multilevel data

    NARCIS (Netherlands)

    Jak, S.; Oort, F.J.; Dolan, C.V.

    2014-01-01

    Measurement bias can be detected using structural equation modeling (SEM), by testing measurement invariance with multigroup factor analysis (Jöreskog, 1971;Meredith, 1993;Sörbom, 1974) MIMIC modeling (Muthén, 1989) or restricted factor analysis (Oort, 1992,1998). In educational research, data often

  15. Attentional bias in math anxiety.

    Science.gov (United States)

    Rubinsten, Orly; Eidlin, Hili; Wohl, Hadas; Akibli, Orly

    2015-01-01

    Cognitive theory from the field of general anxiety suggests that the tendency to display attentional bias toward negative information results in anxiety. Accordingly, the current study aims to investigate whether attentional bias is involved in math anxiety (MA) as well (i.e., a persistent negative reaction to math). Twenty seven participants (14 with high levels of MA and 13 with low levels of MA) were presented with a novel computerized numerical version of the well established dot probe task. One of six types of prime stimuli, either math related or typically neutral, was presented on one side of a computer screen. The prime was preceded by a probe (either one or two asterisks) that appeared in either the prime or the opposite location. Participants had to discriminate probe identity (one or two asterisks). Math anxious individuals reacted faster when the probe was at the location of the numerical related stimuli. This suggests the existence of attentional bias in MA. That is, for math anxious individuals, the cognitive system selectively favored the processing of emotionally negative information (i.e., math related words). These findings suggest that attentional bias is linked to unduly intense MA symptoms.

  16. Sex bias in infectious disease epidemiology: patterns and processes.

    Directory of Open Access Journals (Sweden)

    Felipe Guerra-Silveira

    Full Text Available BACKGROUND: Infectious disease incidence is often male-biased. Two main hypotheses have been proposed to explain this observation. The physiological hypothesis (PH emphasizes differences in sex hormones and genetic architecture, while the behavioral hypothesis (BH stresses gender-related differences in exposure. Surprisingly, the population-level predictions of these hypotheses are yet to be thoroughly tested in humans. METHODS AND FINDINGS: For ten major pathogens, we tested PH and BH predictions about incidence and exposure-prevalence patterns. Compulsory-notification records (Brazil, 2006-2009 were used to estimate age-stratified ♂:♀ incidence rate ratios for the general population and across selected sociological contrasts. Exposure-prevalence odds ratios were derived from 82 published surveys. We estimated summary effect-size measures using random-effects models; our analyses encompass ∼0.5 million cases of disease or exposure. We found that, after puberty, disease incidence is male-biased in cutaneous and visceral leishmaniasis, schistosomiasis, pulmonary tuberculosis, leptospirosis, meningococcal meningitis, and hepatitis A. Severe dengue is female-biased, and no clear pattern is evident for typhoid fever. In leprosy, milder tuberculoid forms are female-biased, whereas more severe lepromatous forms are male-biased. For most diseases, male bias emerges also during infancy, when behavior is unbiased but sex steroid levels transiently rise. Behavioral factors likely modulate male-female differences in some diseases (the leishmaniases, tuberculosis, leptospirosis, or schistosomiasis and age classes; however, average exposure-prevalence is significantly sex-biased only for Schistosoma and Leptospira. CONCLUSIONS: Our results closely match some key PH predictions and contradict some crucial BH predictions, suggesting that gender-specific behavior plays an overall secondary role in generating sex bias. Physiological differences, including

  17. Selection bias in the reported performances of AD classification pipelines.

    Science.gov (United States)

    Mendelson, Alex F; Zuluaga, Maria A; Lorenzi, Marco; Hutton, Brian F; Ourselin, Sébastien

    2017-01-01

    The last decade has seen a great proliferation of supervised learning pipelines for individual diagnosis and prognosis in Alzheimer's disease. As more pipelines are developed and evaluated in the search for greater performance, only those results that are relatively impressive will be selected for publication. We present an empirical study to evaluate the potential for optimistic bias in classification performance results as a result of this selection. This is achieved using a novel, resampling-based experiment design that effectively simulates the optimisation of pipeline specifications by individuals or collectives of researchers using cross validation with limited data. Our findings indicate that bias can plausibly account for an appreciable fraction (often greater than half) of the apparent performance improvement associated with the pipeline optimisation, particularly in small samples. We discuss the consistency of our findings with patterns observed in the literature and consider strategies for bias reduction and mitigation.

  18. Biased selection within the social health insurance market in Colombia.

    Science.gov (United States)

    Castano, Ramon; Zambrano, Andres

    2006-12-01

    Reducing the impact of insurance market failures with regulations such as community-rated premiums, standardized benefit packages and open enrolment, yield limited effect because they create room for selection bias. The Colombian social health insurance system started a market approach in 1993 expecting to improve performance of preexisting monopolistic insurance funds by exposing them to competition by new entrants. This paper tests the hypothesis that market failures would lead to biased selection favoring new entrants. Two household surveys are analyzed using Self-Reported Health Status and the presence of chronic conditions as prospective indicators of individual risk. Biased selection is found to take place, leading to adverse selection among incumbents, and favorable selection among new entrants. This pattern is absent in 1997 but is evident in 2003. Given that the two incumbents analyzed are public organizations, the fiscal implications of the findings in terms of government bailouts, are analyzed.

  19. Biased sampling, over-identified parameter problems and beyond

    CERN Document Server

    Qin, Jing

    2017-01-01

    This book is devoted to biased sampling problems (also called choice-based sampling in Econometrics parlance) and over-identified parameter estimation problems. Biased sampling problems appear in many areas of research, including Medicine, Epidemiology and Public Health, the Social Sciences and Economics. The book addresses a range of important topics, including case and control studies, causal inference, missing data problems, meta-analysis, renewal process and length biased sampling problems, capture and recapture problems, case cohort studies, exponential tilting genetic mixture models etc. The goal of this book is to make it easier for Ph. D students and new researchers to get started in this research area. It will be of interest to all those who work in the health, biological, social and physical sciences, as well as those who are interested in survey methodology and other areas of statistical science, among others. .

  20. Bias Adjusted Precipitation Threat Scores

    Directory of Open Access Journals (Sweden)

    F. Mesinger

    2008-04-01

    Full Text Available Among the wide variety of performance measures available for the assessment of skill of deterministic precipitation forecasts, the equitable threat score (ETS might well be the one used most frequently. It is typically used in conjunction with the bias score. However, apart from its mathematical definition the meaning of the ETS is not clear. It has been pointed out (Mason, 1989; Hamill, 1999 that forecasts with a larger bias tend to have a higher ETS. Even so, the present author has not seen this having been accounted for in any of numerous papers that in recent years have used the ETS along with bias "as a measure of forecast accuracy".

    A method to adjust the threat score (TS or the ETS so as to arrive at their values that correspond to unit bias in order to show the model's or forecaster's accuracy in extit{placing} precipitation has been proposed earlier by the present author (Mesinger and Brill, the so-called dH/dF method. A serious deficiency however has since been noted with the dH/dF method in that the hypothetical function that it arrives at to interpolate or extrapolate the observed value of hits to unit bias can have values of hits greater than forecast when the forecast area tends to zero. Another method is proposed here based on the assumption that the increase in hits per unit increase in false alarms is proportional to the yet unhit area. This new method removes the deficiency of the dH/dF method. Examples of its performance for 12 months of forecasts by three NCEP operational models are given.

  1. Cognitive bias and unusual experiences in childhood.

    Science.gov (United States)

    Hassanali, Nedah; Ruffell, Tamatha; Browning, Sophie; Bracegirdle, Karen; Ames, Catherine; Corrigall, Richard; Laurens, Kristin R; Hirsch, Colette; Kuipers, Elizabeth; Maddox, Lucy; Jolley, Suzanne

    2015-08-01

    Cognitive therapy is recommended for children with psychotic-like, or unusual, experiences associated with distress or impairment (UEDs; UK National Institute for Health and Care Excellence, 2013 [1]). Accurate models of the psychological underpinnings of childhood UEDs are required to effectively target therapies. Cognitive biases, such as the jumping to conclusions data-gathering bias (JTC), are implicated in the development and maintenance of psychosis in adults. In this study, we aimed to establish the suitability for children of a task developed to assess JTC in adults. Eighty-six participants (aged 5-14 years) were recruited from Child and Adolescent Mental Health Service (CAMHS) and community (school) settings, and completed the probabilistic reasoning ('Beads') task, alongside measures of intellectual functioning, general psychopathology, and UEDs. Self-reported reasoning strategy was coded as 'probabilistic' or 'other'. Younger children (5-10 years) were more likely than older children (11-14 years) to JTC (OR = 2.7, 95 % CI = 1.1-6.5, p = 0.03); and to use non-probabilistic reasoning strategies (OR = 9.4, 95 % CI = 1.7-48.8, p = 0.008). Both UED presence (OR = 5.1, 95 % CI = 1.2-21.9, p = 0.03) and lower IQ (OR = 0.9, 95 % CI = 0.9-1.0, p = 0.02) were significantly and independently associated with JTC, irrespective of age and task comprehension. Findings replicate research in adults, indicating that the 'Beads' task can be reliably employed in children to assess cognitive biases. Psychological treatments for children with distressing unusual experiences might usefully incorporate reasoning interventions.

  2. Information environment, behavioral biases, and home bias in analysts’ recommendations

    DEFF Research Database (Denmark)

    Farooq, Omar; Taouss, Mohammed

    2012-01-01

    ’ recommendations. Using a large data of analysts’ recommendations from Asian emerging markets, we show that local analysts issue more optimistic recommendations than their foreign counterparts. However, optimism difference between the two groups is greater for firms with poor information environment. Our results......Can information environment of a firm explain home bias in analysts’ recommendations? Can the extent of agency problems explain optimism difference between foreign and local analysts? This paper answers these questions by documenting the effect of information environment on home bias in analysts...... show that optimism difference between the two groups is more than twice as much in firms with poor information environment than in firms with better information environment. We argue that poor information environment pose greater information asymmetries to foreign analysts regarding local firms...

  3. Conclusions of the presidency. European council of Barcelona, March 15 and 16 2002; Conclusions de la presidence. Conseil europeen de Barcelone 15 et 16 mars 2002

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    This document summarizes the conclusions of the European Council held in Barcelona (Spain) on March 15 and 16, 2002. Among the priority actions listed by the council figure the integration of energy, transportation and communication networks at the European scale. In particular, the council commits the Parliament and itself to start the final phase of opening of gas and electricity markets: free choice of a supplier, obligation of public utility, security of supplies, separation between transmission and distribution and between production and supply, non-discriminatory access of consumers and suppliers to networks with transparent tariffs, establishment of a regulatory agency in each member state, agreement for a tariffing system for the international electricity trades etc.. Concerning the sustainable development strategy of the European union, the council is pressing the member states for the completion of the national procedures of ratification of the Kyoto protocol. However, new measures need to be taken to develop technologies respectful for the environment, in particular in the domain of energy and transports. (J.S.)

  4. Trait and social anxiety in adults with chronic stuttering: conclusions following meta-analysis.

    Science.gov (United States)

    Craig, Ashley; Tran, Yvonne

    2014-06-01

    The relationship between chronic stuttering and anxiety has been a matter of some debate over the past two decades, with a major emphasis of research focused on examining whether people who stutter have abnormally elevated levels of trait or social anxiety. The major goal of this paper was to perform a systematic literature review and perform meta-analyses on research that has assessed (i) trait anxiety and (ii) social anxiety, in adults who stutter. Only studies that met strict inclusion criteria were selected for the meta-analyses. Two meta-analyses were conducted, the first for trait anxiety, and the second for social anxiety. Meta-analysis combines statistically the results of selected studies that meet strict design criteria, thereby clarifying the size of differences in trait and social anxiety between adults who stutter and adults who do not stutter. Meta-analytic results confirmed that adults with chronic stuttering do have substantially elevated trait and social anxiety. The overall effect size for trait and social anxiety was calculated to be .57 and .82, respectively. Trait and social anxiety are definite problems for many adults who stutter. Clinical implications of these findings for the diagnosis and treatment of adult who stutter are discussed. The reader will be able to: (a) describe the process of conducting a systematic review and meta-analysis; (b) describe the possible impact of publication bias on meta-analysis results; (c) explain the impact of a chronic disorder like stuttering on levels of trait anxiety; (d) explain the impact of stuttering on levels of social anxiety; (e) interpret the results of meta-analysis when applied to differences in anxiety between adult people who stutter and those who do not stutter; and (f) describe implications for fluency enhancing treatments. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Public Education, Public Good.

    Science.gov (United States)

    Tomlinson, John

    1986-01-01

    Criticizes policies which would damage or destroy a public education system. Examines the relationship between government-provided education and democracy. Concludes that privatization of public education would emphasize self-interest and selfishness, further jeopardizing the altruism and civic mindedness necessary for the public good. (JDH)

  6. Ombud’s Corner: defeating unconscious bias

    CERN Multimedia

    Sudeshna Datta-Cockerill

    2016-01-01

    Do you have a tendency to switch off at meetings every time a particular colleague starts to speak? Is it obvious to you that your colleagues will never accept a peer as a project leader? And doesn’t that candidate from your own alma mater clearly have a definite edge over the others?   How do we come to these conclusions and what can we do to ensure that our decisions are based on objective criteria alone? Can we always be sure that we are not influenced by pre-conceived notions or prejudices that may unconsciously bias our thinking? Unconscious bias is a part of everyday life – it refers to the insidious influences that our backgrounds, cultural environments or personal experiences exert on the way in which we judge or assess people or situations. In the workplace, it has a negative impact on our goals and interactions when it causes us to make decisions based on generalisations or mental associations that we are not even aware of, and that have little or no bearing on the o...

  7. Quality of evidence revealing subtle gender biases in science is in the eye of the beholder.

    Science.gov (United States)

    Handley, Ian M; Brown, Elizabeth R; Moss-Racusin, Corinne A; Smith, Jessi L

    2015-10-27

    Scientists are trained to evaluate and interpret evidence without bias or subjectivity. Thus, growing evidence revealing a gender bias against women-or favoring men-within science, technology, engineering, and mathematics (STEM) settings is provocative and raises questions about the extent to which gender bias may contribute to women's underrepresentation within STEM fields. To the extent that research illustrating gender bias in STEM is viewed as convincing, the culture of science can begin to address the bias. However, are men and women equally receptive to this type of experimental evidence? This question was tested with three randomized, double-blind experiments-two involving samples from the general public (n = 205 and 303, respectively) and one involving a sample of university STEM and non-STEM faculty (n = 205). In all experiments, participants read an actual journal abstract reporting gender bias in a STEM context (or an altered abstract reporting no gender bias in experiment 3) and evaluated the overall quality of the research. Results across experiments showed that men evaluate the gender-bias research less favorably than women, and, of concern, this gender difference was especially prominent among STEM faculty (experiment 2). These results suggest a relative reluctance among men, especially faculty men within STEM, to accept evidence of gender biases in STEM. This finding is problematic because broadening the participation of underrepresented people in STEM, including women, necessarily requires a widespread willingness (particularly by those in the majority) to acknowledge that bias exists before transformation is possible.

  8. The Influence of Activation Level on Belief Bias in Relational Reasoning

    Science.gov (United States)

    Banks, Adrian P.

    2013-01-01

    A novel explanation of belief bias in relational reasoning is presented based on the role of working memory and retrieval in deductive reasoning, and the influence of prior knowledge on this process. It is proposed that belief bias is caused by the believability of a conclusion in working memory which influences its activation level, determining…

  9. Types of Research Bias Encountered in IR.

    Science.gov (United States)

    Gabr, Ahmed; Kallini, Joseph Ralph; Desai, Kush; Hickey, Ryan; Thornburg, Bartley; Kulik, Laura; Lewandowski, Robert J; Salem, Riad

    2016-04-01

    Bias is a systemic error in studies that leads to inaccurate deductions. Relevant biases in the field of IR and interventional oncology were identified after reviewing articles published in the Journal of Vascular and Interventional Radiology and CardioVascular and Interventional Radiology. Biases cited in these articles were divided into three categories: preinterventional (health care access, participation, referral, and sample biases), periinterventional (contamination, investigator, and operator biases), and postinterventional (guarantee-time, lead time, loss to follow-up, recall, and reporting biases). Copyright © 2016 SIR. Published by Elsevier Inc. All rights reserved.

  10. Probability biases as Bayesian inference

    Directory of Open Access Journals (Sweden)

    Andre; C. R. Martins

    2006-11-01

    Full Text Available In this article, I will show how several observed biases in human probabilistic reasoning can be partially explained as good heuristics for making inferences in an environment where probabilities have uncertainties associated to them. Previous results show that the weight functions and the observed violations of coalescing and stochastic dominance can be understood from a Bayesian point of view. We will review those results and see that Bayesian methods should also be used as part of the explanation behind other known biases. That means that, although the observed errors are still errors under the be understood as adaptations to the solution of real life problems. Heuristics that allow fast evaluations and mimic a Bayesian inference would be an evolutionary advantage, since they would give us an efficient way of making decisions. %XX In that sense, it should be no surprise that humans reason with % probability as it has been observed.

  11. Mindfulness reduces the correspondence bias.

    Science.gov (United States)

    Hopthrow, Tim; Hooper, Nic; Mahmood, Lynsey; Meier, Brian P; Weger, Ulrich

    2017-03-01

    The correspondence bias (CB) refers to the idea that people sometimes give undue weight to dispositional rather than situational factors when explaining behaviours and attitudes. Three experiments examined whether mindfulness, a non-judgmental focus on the present moment, could reduce the CB. Participants engaged in a brief mindfulness exercise (the raisin task), a control task, or an attention to detail task before completing a typical CB measure involving an attitude-attribution paradigm. The results indicated that participants in the mindfulness condition experienced a significant reduction in the CB compared to participants in the control or attention to detail conditions. These results suggest that mindfulness training can play a unique role in reducing social biases related to person perception.

  12. Opinion Dynamics with Confirmation Bias

    CERN Document Server

    Allahverdyan, A E

    2014-01-01

    Background: 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. Methodology/Principal Findings: 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 preferenc...

  13. Are temperature reconstructions regionally biased?

    CERN Document Server

    Bothe, O

    2012-01-01

    Are temperature reconstructions possibly biased due to regionally differing density of utilized proxy-networks? This question is assessed utilizing a simple process-based forward model of tree growth in the virtual reality of two simulations of the climate of the last millennium with different amplitude of solar forcing variations. The pseudo-tree ring series cluster in high latitudes of the northern hemisphere and east Asia. Only weak biases are found for the full network. However, for a strong solar forcing amplitude the high latitudes indicate a warmer first half of the last millennium while mid-latitudes and Asia were slightly colder than the extratropical hemispheric average. Reconstruction skill is weak or non-existent for two simple reconstruction schemes, and comparison of virtual reality target and reconstructions reveals strong deficiencies. The temporal resolution of the proxies has an influence on the reconstruction task and results are sensitive to the construction of the proxy-network. Existing ...

  14. Competition and Commercial Media Bias

    OpenAIRE

    A. Blasco; F. Sobbrio

    2011-01-01

    This paper reviews the empirical evidence on commercial media bias (i.e., advertisers influence over media accuracy) and then introduces a simple model to summarize the main elements of the theoretical literature. The analysis provides three main policy insights for media regulators: i) Media regulators should target their monitoring efforts towards news contents upon which advertisers are likely to share similar preferences; ii) In advertising industries characterized by high correlation in ...

  15. BEHAVIORAL BIASES IN TRADING SECURITIES

    Directory of Open Access Journals (Sweden)

    Turcan Ciprian Sebastian

    2010-12-01

    Full Text Available The main thesis of this paper represents the importance and the effects that human behavior has over capital markets. It is important to see the link between the asset valuation and investor sentiment that motivate to pay for an asset a certain prices over/below the intrinsic value. The main behavioral aspects discussed are emotional factors such as: fear of regret, overconfidence, perseverance, loss aversion ,heuristic biases, misinformation and thinking errors, herding and their consequences.

  16. Measuring bias from unbiased observable

    CERN Document Server

    Lee, Seokcheon

    2014-01-01

    Since Kaiser introduced galaxies as a biased tracer of the underlying total mass field, the linear galaxies bias, b(z) appears ubiquitously both in theoretical calculations and in observational measurements related to galaxy surveys. However, the generic approaches to the galaxy density is a non-local and stochastic function of the underlying dark matter density and it becomes difficult to make the analytic form of b(z). Due to this fact, b(z) is known as a nuisance parameter and the effort has been made to measure bias free observable quantities. We provide the exact and analytic function of b(z) which also can be measured from galaxy surveys using the redshift space distortions parameters, more accurately unbiased observable \\beta \\sigma_{\\rm{gal}} = f \\sigma_8. We also introduce approximate solutions for b(z) for different gravity theories. One can generalize these approximate solutions to be exact when one solves the exact evolutions for the dark matter density fluctuation of given gravity theories. These...

  17. Response bias in plaintiffs' histories.

    Science.gov (United States)

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

    1997-11-01

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

  18. Opinion dynamics with confirmation bias.

    Science.gov (United States)

    Allahverdyan, Armen E; Galstyan, Aram

    2014-01-01

    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.

  19. 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.

  20. Public Relations in the Public Sector

    DEFF Research Database (Denmark)

    Valentini, Chiara

    2013-01-01

    of the Excellence Project in Public Relations and thus applies a research instrument similar to that used in other international scholarly investigations in public relations. The population comprises civil servants working in information and communication activities for Italian public administrations. Findings...... relations. Research limitations: Due to a lack of information on the exact number of public communication officers working in the Italian public administration and a too small number of respondents in one of the respondent groups, it is not possible to draw inferences or general conclusions from...... knowledge on strategic public relations and public communication by offering a specific analysis of the strategic management of information and communication programs in the Italian public administration....

  1. The Contingent Valuation Method in Public Libraries

    Science.gov (United States)

    Chung, Hye-Kyung

    2008-01-01

    This study aims to present a new model measuring the economic value of public libraries, combining the dissonance minimizing (DM) and information bias minimizing (IBM) format in the contingent valuation (CV) surveys. The possible biases which are tied to the conventional CV surveys are reviewed. An empirical study is presented to compare the model…

  2. The Contingent Valuation Method in Public Libraries

    Science.gov (United States)

    Chung, Hye-Kyung

    2008-01-01

    This study aims to present a new model measuring the economic value of public libraries, combining the dissonance minimizing (DM) and information bias minimizing (IBM) format in the contingent valuation (CV) surveys. The possible biases which are tied to the conventional CV surveys are reviewed. An empirical study is presented to compare the model…

  3. Health Indicators: Eliminating bias from convenience sampling estimators

    OpenAIRE

    Hedt, Bethany L.; Pagano, Marcello

    2011-01-01

    Public health practitioners are often called upon to make inference about a health indicator for a population at large when the sole available information are data gathered from a convenience sample, such as data gathered on visitors to a clinic. These data may be of the highest quality and quite extensive, but the biases inherent in a convenience sample preclude the legitimate use of powerful inferential tools that are usually associated with a random sample. In general, we know nothing abou...

  4. Aging and recognition memory for emotional words: a bias account.

    Science.gov (United States)

    Thapar, Anjali; Rouder, Jeffrey N

    2009-08-01

    The present study investigated age-related differences in the locus of the emotional enhancement effect in recognition memory. Younger and older adults studied an emotion-heterogeneous list followed by a forced choice recognition memory test. Luce's (1963) similarity choice model was used to assess whether emotional valence impacts memory sensitivity or response bias. Results revealed that the emotional enhancement effect in both age groups was due to a more liberal response bias for emotional words. However, the pattern of bias differed, with younger adults more willing to classify negative words as old and older adults more willing to classify positive words as old. The results challenge the conclusion that emotional words are more memorable than neutral words.

  5. Topical interests and the mitigation of search engine bias.

    Science.gov (United States)

    Fortunato, S; Flammini, A; Menczer, F; Vespignani, A

    2006-08-22

    Search engines have become key media for our scientific, economic, and social activities by enabling people to access information on the web despite its size and complexity. On the down side, search engines bias the traffic of users according to their page ranking strategies, and it has been argued that they create a vicious cycle that amplifies the dominance of established and already popular sites. This bias could lead to a dangerous monopoly of information. We show that, contrary to intuition, empirical data do not support this conclusion; popular sites receive far less traffic than predicted. We discuss a model that accurately predicts traffic data patterns by taking into consideration the topical interests of users and their searching behavior in addition to the way search engines rank pages. The heterogeneity of user interests explains the observed mitigation of search engines' popularity bias.

  6. Matrilateral Bias in Human Grandmothering

    Directory of Open Access Journals (Sweden)

    Martin Daly

    2017-09-01

    Full Text Available Children receive more care and resources from their maternal grandmothers than from their paternal grandmothers. This asymmetry is the “matrilateral bias” in grandmaternal investment. Here, we synopsize the evolutionary theories that predict such a bias, and review evidence of its cross-cultural generality and magnitude. Evolutionists have long maintained that investing in a daughter’s child yields greater fitness returns, on average, than investing in a son’s child because of paternity uncertainty: the son’s putative progeny may have been sired by someone else. Recent theoretical work has identified an additional natural selective basis for the matrilateral bias that may be no less important: supporting grandchildren lightens the load on their mother, increasing her capacity to pursue her fitness in other ways, and if she invests those gains either in her natal relatives or in children of a former or future partner, fitness returns accrue to the maternal, but not the paternal, grandmother. In modern democracies, where kinship is reckoned bilaterally and no postmarital residence norms restrict grandmaternal access to grandchildren, many studies have found large matrilateral biases in contact, childcare, and emotional closeness. In other societies, patrilineal ideology and postmarital residence with the husband’s kin (virilocality might be expected to have produced a patrilateral bias instead, but the available evidence refutes this hypothesis. In hunter-gatherers, regardless of professed norms concerning kinship and residence, mothers get needed help at and after childbirth from their mothers, not their mothers-in-law. In traditional agricultural and pastoral societies, patrilineal and virilocal norms are common, but young mothers still turn to their natal families for crucial help, and several studies have documented benefits, including reduced child mortality, associated with access to maternal, but not paternal, grandmothers. Even

  7. Bias-correction in vector autoregressive models

    DEFF Research Database (Denmark)

    Engsted, Tom; Pedersen, Thomas Quistgaard

    2014-01-01

    We analyze the properties of various methods for bias-correcting parameter estimates in both stationary and non-stationary vector autoregressive models. First, we show that two analytical bias formulas from the existing literature are in fact identical. Next, based on a detailed simulation study......, we show that when the model is stationary this simple bias formula compares very favorably to bootstrap bias-correction, both in terms of bias and mean squared error. In non-stationary models, the analytical bias formula performs noticeably worse than bootstrapping. Both methods yield a notable...... improvement over ordinary least squares. We pay special attention to the risk of pushing an otherwise stationary model into the non-stationary region of the parameter space when correcting for bias. Finally, we consider a recently proposed reduced-bias weighted least squares estimator, and we find...

  8. The Probability Distribution for a Biased Spinner

    Science.gov (United States)

    Foster, Colin

    2012-01-01

    This article advocates biased spinners as an engaging context for statistics students. Calculating the probability of a biased spinner landing on a particular side makes valuable connections between probability and other areas of mathematics. (Contains 2 figures and 1 table.)

  9. The Probability Distribution for a Biased Spinner

    Science.gov (United States)

    Foster, Colin

    2012-01-01

    This article advocates biased spinners as an engaging context for statistics students. Calculating the probability of a biased spinner landing on a particular side makes valuable connections between probability and other areas of mathematics. (Contains 2 figures and 1 table.)

  10. Perceptual other-race training reduces implicit racial bias.

    Directory of Open Access Journals (Sweden)

    Sophie Lebrecht

    Full Text Available BACKGROUND: Implicit racial bias denotes socio-cognitive attitudes towards other-race groups that are exempt from conscious awareness. In parallel, other-race faces are more difficult to differentiate relative to own-race faces--the "Other-Race Effect." To examine the relationship between these two biases, we trained Caucasian subjects to better individuate other-race faces and measured implicit racial bias for those faces both before and after training. METHODOLOGY/PRINCIPAL FINDINGS: Two groups of Caucasian subjects were exposed equally to the same African American faces in a training protocol run over 5 sessions. In the individuation condition, subjects learned to discriminate between African American faces. In the categorization condition, subjects learned to categorize faces as African American or not. For both conditions, both pre- and post-training we measured the Other-Race Effect using old-new recognition and implicit racial biases using a novel implicit social measure--the "Affective Lexical Priming Score" (ALPS. Subjects in the individuation condition, but not in the categorization condition, showed improved discrimination of African American faces with training. Concomitantly, subjects in the individuation condition, but not the categorization condition, showed a reduction in their ALPS. Critically, for the individuation condition only, the degree to which an individual subject's ALPS decreased was significantly correlated with the degree of improvement that subject showed in their ability to differentiate African American faces. CONCLUSIONS/SIGNIFICANCE: Our results establish a causal link between the Other-Race Effect and implicit racial bias. We demonstrate that training that ameliorates the perceptual Other-Race Effect also reduces socio-cognitive implicit racial bias. These findings suggest that implicit racial biases are multifaceted, and include malleable perceptual skills that can be modified with relatively little training.

  11. 'Journal Bias' in peer-reviewed literature: an analysis of the surgical high-grade glioma literature.

    Science.gov (United States)

    Hirshman, Brian R; Jones, Laurie A; Tang, Jessica A; Proudfoot, James A; Carley, Kathleen M; Carter, Bob S; Chen, Clark C

    2016-11-01

    The core premise of evidence-based medicine is that clinical decisions are informed by the peer-reviewed literature. To extract meaningful conclusions from this literature, one must first understand the various forms of biases inherent within the process of peer review. We performed an exhaustive search that identified articles exploring the question of whether survival benefit was associated with maximal high-grade glioma (HGG) resection and analysed this literature for patterns of publication. We found that the distribution of these 108 articles among the 26 journals to be non-random (p<0.01), with 75 of the 108 published articles (69%) appearing in 6 of the 26 journals (25%). Moreover, certain journals were likely to publish a large number of articles from the same medical academic genealogy (authors with shared training history and/or mentor). We term the tendency of certain types of articles to be published in select journals 'journal bias' and discuss the implication of this form of bias as it pertains to evidence-based medicine. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  12. A Pharmacological Primer of Biased Agonism

    OpenAIRE

    Andresen, Bradley T.

    2011-01-01

    Biased agonism is one of the fastest growing topics in G protein-coupled receptor pharmacology; moreover, biased agonists are used in the clinic today: carvedilol (Coreg®) is a biased agonist of beta-adrenergic receptors. However, there is a general lack of understanding of biased agonism when compared to traditional pharmacological terminology. Therefore, this review is designed to provide a basic introduction to classical pharmacology as well as G protein-coupled receptor signal transductio...

  13. Assessment of replicate bias in 454 pyrosequencing and a multi-purpose read-filtering tool

    Directory of Open Access Journals (Sweden)

    Klopp Christophe

    2011-05-01

    Full Text Available Abstract Background Roche 454 pyrosequencing platform is often considered the most versatile of the Next Generation Sequencing technology platforms, permitting the sequencing of large genomes, the analysis of variations or the study of transcriptomes. A recent reported bias leads to the production of multiple reads for a unique DNA fragment in a random manner within a run. This bias has a direct impact on the quality of the measurement of the representation of the fragments using the reads. Other cleaning steps are usually performed on the reads before assembly or alignment. Findings PyroCleaner is a software module intended to clean 454 pyrosequencing reads in order to ease the assembly process. This program is a free software and is distributed under the terms of the GNU General Public License as published by the Free Software Foundation. It implements several filters using criteria such as read duplication, length, complexity, base-pair quality and number of undetermined bases. It also permits to clean flowgram files (.sff of paired-end sequences generating on one hand validated paired-ends file and the other hand single read file. Conclusions Read cleaning has always been an important step in sequence analysis. The pyrocleaner python module is a Swiss knife dedicated to 454 reads cleaning. It includes commonly used filters as well as specialised ones such as duplicated read removal and paired-end read verification.

  14. Scientific Opinion updating the risk assessment conclusions and risk management recommendations on the genetically modified insect resistant maize MON 810

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Genetically Modified Organisms (GMO

    2012-12-01

    Full Text Available Following a request from the European Commission, the Panel on Genetically Modified Organisms of the European Food Safety Authority (EFSA GMO Panel compiled its previous risk assessment conclusions and risk management recommendations on the genetically modified insect resistant maize MON 810, and considered their validity in the light of new relevant scientific publications published from 2009 onwards. Following a search of the scientific literature published between 2009 and October 2012, the EFSA GMO Panel identified 165 peer-reviewed publications containing evidence specific to the risk assessment and/or management of maize MON 810, of which 68 publications were discussed and/or cited in previous EFSA GMO Panel scientific outputs. From the remaining 97 publications, eight were relevant for the molecular characterisation, 27 for food and feed safety assessment, 55 for the environmental risk assessment and/or risk management, two for the molecular characterisation and the environmental risk assessment and/or risk management and five for the food and feed safety assessment and the environmental risk assessment and/or risk management of maize MON 810. None of these publications reported new information that would invalidate the previous conclusions on the safety of maize MON 810 made by the EFSA GMO Panel. Therefore, the EFSA GMO Panel considers that its previous risk assessment conclusions on maize MON 810, as well as its previous recommendations on risk mitigation measures and monitoring, remain valid and applicable.

  15. Scientific Opinion updating the risk assessment conclusions and risk management recommendations on the genetically modified insect resistant maize Bt11

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Genetically Modified Organisms (GMO

    2012-12-01

    Full Text Available Following a request from the European Commission, the Panel on Genetically Modified Organisms of the European Food Safety Authority (EFSA GMO Panel compiled its previous risk assessment conclusions and risk management recommendations on the genetically modified insect resistant maize Bt11, and considered their validity in the light of new relevant scientific publications published from 2005 onwards. Following a search of the scientific literature published between 2005 and October 2012, the EFSA GMO Panel identified 287 peer-reviewed publications containing evidence specific to the risk assessment and/or management of maize Bt11, of which 270 publications were previously discussed and cited in relevant GM maize-related applications and/or the numerous EFSA GMO Panel scientific outputs. From the remaining 17 publications, three were relevant for the food and feed safety assessment, and 14 for the environmental risk assessment and/or risk management of maize Bt11. None of these publications reported new information that would invalidate the previous conclusions on the safety of maize Bt11 made by the EFSA GMO Panel. Therefore, the EFSA GMO Panel considers that its previous risk assessment conclusions on maize Bt11, as well as its previous recommendations on risk mitigation measures and monitoring, remain valid and applicable.

  16. Conclusions from the Mexican National Nutrition Survey 1999: translating results into nutrition policy

    Directory of Open Access Journals (Sweden)

    Rivera Juan A

    2003-01-01

    Full Text Available OBJECTIVE: This article presents and overview of the main results and conclusions from the Mexican National Nutrition Survey 1999 (NNS-1999 and the principal nutrition policy implications of the findings. MATERIAL AND METHODS: The NNS-1999 was conducted on a national probabilistic sample of almost 18 000 households, representative of the national, regional, as well as urban and rural levels in Mexico. Subjects included were children <12 years and women 12-49 years. Anthropometry, blood specimens, diet and socioeconomic information of the family were collected. RESULTS: The principal public nutrition problems are stunting in children < 5 years of age; anemia, iron and zinc deficiency, and low serum vitamin C concentrations at all ages; and vitamin A deficiency in children. Undernutrition (stunting and micronutrient deficiencies was generally more prevalent in the lower socioeconomic groups, in rural areas, in the south and in Indigenous population. Overweight and obesity are serious public health problems in women and are already a concern in school-age children. CONCLUSIONS: A number of programs aimed at preventing undernutrition are currently in progress; several of them were designed or modified as a result of the NNS-1999 findings. Most of them have an evaluation component that will inform adjustments or modifications of their design and implementation. However, little is being done for the prevention and control of overweight and obesity and there is limited experience on effective interventions. The design and evaluation of prevention strategies for controlling obesity in the population, based on existing evidence, is urgently needed and success stories should be brought to scale quickly to maximize impact.

  17. Attentional bias predicts heroin relapse following treatment

    NARCIS (Netherlands)

    M.A.E. Marissen; I.H.A. Franken; A.J. Waters; P. Blanken; W. van den Brink; V.M. Hendriks

    2006-01-01

    Aims Previous studies have shown that abstinent heroin addicts exhibit an attentional bias to heroin-related stimuli. It has been suggested that attentional bias may represent a vulnerability to relapse into drug use. In the present study, the predictive value of pre-treatment attentional bias on re

  18. Using Newspapers to Study Media Bias.

    Science.gov (United States)

    Kirman, Joseph M.

    1992-01-01

    Suggests that students can learn to recognize media bias by studying media reports of current events or historical topics. Describes a study unit using media coverage of the second anniversary of the Palestinian uprising against Israel. Discusses lesson objectives, planning, defining bias teaching procedures, and criteria for determining bias. (DK)

  19. Culturally Biased Assumptions in Counseling Psychology

    Science.gov (United States)

    Pedersen, Paul B.

    2003-01-01

    Eight clusters of culturally biased assumptions are identified for further discussion from Leong and Ponterotto's (2003) article. The presence of cultural bias demonstrates that cultural bias is so robust and pervasive that is permeates the profession of counseling psychology, even including those articles that effectively attack cultural bias…

  20. Public Speech.

    Science.gov (United States)

    Green, Thomas F.

    1994-01-01

    Discusses the importance of public speech in society, noting the power of public speech to create a world and a public. The paper offers a theory of public speech, identifies types of public speech, and types of public speech fallacies. Two ways of speaking of the public and of public life are distinguished. (SM)

  1. Globalization, tax distortions and public sector retrenchment

    DEFF Research Database (Denmark)

    Andersen, Torben M.; Sørensen, Allan

    income taxation unambiguously worsens wage competitiveness, it does not follow that marginal costs of public funds increase with product market integration due to gains from trade. Moreover, non-cooperative fiscal policies do not have a race-to-the-bottom bias despite that taxes harm competitiveness....... In fact we identify an expansionary bias in …scal policies that is likely to increase with globalization when taxes finance either public consumption or transfers....

  2. Limitations and sources of bias in clinical knee cartilage research.

    Science.gov (United States)

    Worthen, Jamie; Waterman, Brian R; Davidson, Philip A; Lubowitz, James H

    2012-09-01

    The purpose of this study was to systematically review the limitations and biases inherent to surgical trials on the management of knee chondral defects. A literature search of PubMed/Medline, CINAHL (Cumulative Index to Nursing and Allied Health Literature), EMBASE, and the Cochrane Central Register of Controlled Trials was conducted in September 2010 and updated in August 2011 to identify all English-language, Level I evidence, prospective, randomized controlled trials published from 1996 to present. The keyword search included the following: "autologous chondrocyte," "cartilage graft," "cartilage repair," "chondroplasty," "microfracture," "mosaicplasty," and/or "osteochondral." Nonoperative studies, nonhuman studies, ex vivo studies, non-knee studies, and/or studies with follow-up of less than 1 year were excluded. A systematic review was performed on all included studies, and limitations and/or biases were identified and quantitated. Of 15,311 citations, 33 abstracts were reviewed and 11 prospective, randomized controlled trials were included. We identified 9 major limitations (subject age, subject prior surgery, subject duration of symptoms, lesion location, lesion size, lesion number, procedure selection, procedure standardization, and limited histologic analysis) and 7 common biases (selection, performance, transfer, nonresponder, detection, publication, and study design). Level I therapeutic studies investigating the surgical management of human knee cartilage defects have substantial identified biases and limitations. This review has limitations because other classifications of bias or limitation exist. Optimal management of cartilage defects is controversial, and future rigorous research methods could minimize common biases through strict study design and patient selection criteria, larger patient enrollment, more extended follow-up, and standardization of clinical treatment pathways. Level I, systematic review of Level I studies. Copyright © 2012

  3. A Review of Studies on Media Bias at Home

    Institute of Scientific and Technical Information of China (English)

    辛一丹

    2015-01-01

    Bias is widely existed nowadays.Domestic scholars have done a lot of research on the bias,especially the media bias.They studied the media bias from different perspectives,such as the bias on China image,the bias of a certain media FOX,the bias on the venerable group,the bias on women and so on.The author plans to give a review of the studies on media bias at home in this paper.

  4. A Review of Studies on Media Bias at Home

    Institute of Scientific and Technical Information of China (English)

    辛一丹

    2015-01-01

    Bias is widely existed nowadays. Domestic scholars have done a lot of research on the bias, especially the media bias. They studied the media bias from different perspectives, such as the bias on China image,the bias of a certain media FOX, the bias on the venerable group, the bias on women and so on. The author plans to give a review of the studies on media bias at home in this paper.

  5. Ratio Bias and Policy Preferences

    DEFF Research Database (Denmark)

    Pedersen, Rasmus Tue

    2016-01-01

    Numbers permeate modern political communication. While current scholarship on framing effects has focused on the persuasive effects of words and arguments, this article shows that framing of numbers can also substantially affect policy preferences. Such effects are caused by ratio bias, which...... is a general tendency to focus on numerators and pay insufficient attention to denominators in ratios. Using a population-based survey experiment, I demonstrate how differently framed but logically equivalent representations of the exact same numerical value can have large effects on citizens’ preferences...

  6. Magnetoelectric switching of exchange bias.

    Science.gov (United States)

    Borisov, Pavel; Hochstrat, Andreas; Chen, Xi; Kleemann, Wolfgang; Binek, Christian

    2005-03-25

    The perpendicular exchange bias field, H(EB), of the magnetoelectric heterostructure Cr2O3(111)/(Co/Pt)(3) changes sign after field cooling to below the Néel temperature of Cr2O3 in either parallel or antiparallel axial magnetic and electric freezing fields. The switching of H(EB) is explained by magnetoelectrically induced antiferromagnetic single domains which extend to the interface, where the direction of their end spins controls the sign of H(EB). Novel applications in magnetoelectronic devices seem possible.

  7. Public Relations in the Public Sector

    DEFF Research Database (Denmark)

    Valentini, Chiara

    2013-01-01

    of the Excellence Project in Public Relations and thus applies a research instrument similar to that used in other international scholarly investigations in public relations. The population comprises civil servants working in information and communication activities for Italian public administrations. Findings...... relations. Research limitations: Due to a lack of information on the exact number of public communication officers working in the Italian public administration and a too small number of respondents in one of the respondent groups, it is not possible to draw inferences or general conclusions from...... the findings. The study also suffers from the limits of a quantitative research approach, which provides less elaborate accounts of public communication officers’ perceptions of the strategic role of communication in the public sector. Originality/value of paper: This study contributes to the existing...

  8. Enhancing the credibility of decisions based on scientific conclusions: transparency is imperative.

    Science.gov (United States)

    Schreider, Jay; Barrow, Craig; Birchfield, Norman; Dearfield, Kerry; Devlin, Dennis; Henry, Sara; Kramer, Melissa; Schappelle, Seema; Solomon, Keith; Weed, Douglas L; Embry, Michelle R

    2010-07-01

    Transparency and documentation of the decision process are at the core of a credible risk assessment and, in addition, are essential in the presentation of a weight of evidence (WoE)-based approach. Lack of confidence in the risk assessment process (as the basis for a risk management decision), beginning with evaluation of raw data and continuing through the risk decision process, is largely because of issues surrounding transparency. There is a critical need to implement greater transparency throughout the risk assessment process, and although doing so will not guarantee the correctness of the risk assessment or that all risk assessors come up with the same conclusions, it will provide essential information on how a particular conclusion or decision was made, thereby increasing confidence in the conclusions. Recognizing this issue, the International Life Sciences Institute Health and Environmental Sciences Institute convened a multisector committee tasked with discussing this issue and examining existing guidance and recommendations related to transparency in risk assessment. The committee concluded that transparency is inextricably linked to credibility: credibility of the data, credibility of the risk assessment process, and credibility of the resulting decision making. To increase this credibility, existing guidance concerning criteria elements of transparency related to the risk assessment process must be more widely disseminated and applied, and raw data for studies used in human health and environmental risk assessment must be more widely available. Finally, the decision-making process in risk management must be better documented and a guidance framework established for both the process itself and its communication to the public.

  9. A Simulation Platform for Quantifying Survival Bias

    DEFF Research Database (Denmark)

    Mayeda, Elizabeth Rose; Tchetgen Tchetgen, Eric J; Power, Melinda C

    2016-01-01

    Bias due to selective mortality is a potential concern in many studies and is especially relevant in cognitive aging research because cognitive impairment strongly predicts subsequent mortality. Biased estimation of the effect of an exposure on rate of cognitive decline can occur when mortality i......-mortality situations. This simulation platform provides a flexible tool for evaluating biases in studies with high mortality, as is common in cognitive aging research.......Bias due to selective mortality is a potential concern in many studies and is especially relevant in cognitive aging research because cognitive impairment strongly predicts subsequent mortality. Biased estimation of the effect of an exposure on rate of cognitive decline can occur when mortality...... platform with which to quantify the expected bias in longitudinal studies of determinants of cognitive decline. We evaluated potential survival bias in naive analyses under several selective survival scenarios, assuming that exposure had no effect on cognitive decline for anyone in the population. Compared...

  10. Numeracy and framing bias in epilepsy.

    Science.gov (United States)

    Choi, Hyunmi; Wong, John B; Mendiratta, Anil; Heiman, Gary A; Hamberger, Marla J

    2011-01-01

    Patients with epilepsy are frequently confronted with complex treatment decisions. Communicating treatment risks is often difficult because patients may have difficulty with basic statistical concepts (i.e., low numeracy) or might misconceive the statistical information based on the way information is presented, a phenomenon known as "framing bias." We assessed numeracy and framing bias in 95 adults with chronic epilepsy and explored cognitive correlates of framing bias. Compared with normal controls, patients with epilepsy had significantly poorer performance on the Numeracy scale (P=0.02), despite a higher level of education than normal controls (Pframing bias. Abstract problem solving performance correlated with the degree of framing bias (r=0.631, Pframing bias. Poor numeracy and susceptibility framing bias place patients with epilepsy at risk for uninformed decisions.

  11. Heart Failure Therapeutics on the Basis of a Biased Ligand of the Angiotensin-2 Type 1 Receptor Rationale and Design of the BLAST-AHF Study (Biased Ligand of the Angiotensin Receptor Study in Acute Heart Failure)

    NARCIS (Netherlands)

    Felker, G. Michael; Butler, Javed; Collins, Sean P.; Cotter, Gad; Davison, Beth A.; Ezekowitz, Justin A.; Filippatos, Gerasimos; Levy, Phillip D.; Metra, Marco; Ponikowski, Piotr; Soergel, David G.; Teerlink, John R.; Violin, Jonathan D.; Voors, Adriaan A.; Pang, Peter S.

    2015-01-01

    The BLAST-AHF (Biased Ligand of the Angiotensin Receptor Study in Acute Heart Failure) study is designed to test the efficacy and safety of TRV027, a novel biased ligand of the angiotensin-2 type 1 receptor, in patients with acute heart failure (AHF). AHF remains a major public health problem, and n

  12. Selection bias and the perils of benchmarking.

    Science.gov (United States)

    Denrell, Jerker

    2005-04-01

    To find the secrets of business success, what could be more natural than studying successful businesses? In fact, nothing could be more dangerous, warns this Stanford professor. Generalizing from the examples of successful companies is like generalizing about New England weather from data taken only in the summer. That's essentially what businesspeople do when they learn from good examples and what consultants, authors, and researchers do when they study only existing companies or--worse yet--only high-performing companies. They reach conclusions from unrepresentative data samples, falling into the classic statistical trap of selection bias. Drawing on a wealth of case studies, for instance, one researcher concluded that great leaders share two key traits: They persist, often despite initial failures, and they are able to persuade others to join them. But those traits are also the hallmarks of spectacularly unsuccessful entrepreneurs, who must persist in the face of failure to incur large losses and must be able to persuade others to pour their money down the drain. To discover what makes a business successful, then, managers should look at both successes and failures. Otherwise, they will overvalue risky business practices, seeing only those companies that won big and not the ones that lost dismally. They will not be able to tell if their current good fortune stems from smart business practices or if they are actually coasting on past accomplishments or good luck. Fortunately, economists have developed relatively simple tools that can correct for selection bias even when data about failed companies are hard to come by. Success may be inspirational, but managers are more likely to find the secrets of high performance if they give the stories of their competitors'failures as full a hearing as they do the stories of dazzling successes.

  13. Differential effects of weight bias experiences and internalization on exercise among women with overweight and obesity.

    Science.gov (United States)

    Pearl, Rebecca L; Puhl, Rebecca M; Dovidio, John F

    2015-12-01

    This study investigated the effects of experiences with weight stigma and weight bias internalization on exercise. An online sample of 177 women with overweight and obesity (M(age) = 35.48 years, M(BMI) = 32.81) completed questionnaires assessing exercise behavior, self-efficacy, and motivation; experiences of weight stigmatization; weight bias internalization; and weight-stigmatizing attitudes toward others. Weight stigma experiences positively correlated with exercise behavior, but weight bias internalization was negatively associated with all exercise variables. Weight bias internalization was a partial mediator between weight stigma experiences and exercise behavior. The distinct effects of experiencing versus internalizing weight bias carry implications for clinical practice and public health. © The Author(s) 2014.

  14. High and far: biases in the location of protected areas.

    Directory of Open Access Journals (Sweden)

    Lucas N Joppa

    Full Text Available BACKGROUND: About an eighth of the earth's land surface is in protected areas (hereafter "PAs", most created during the 20(th century. Natural landscapes are critical for species persistence and PAs can play a major role in conservation and in climate policy. Such contributions may be harder than expected to implement if new PAs are constrained to the same kinds of locations that PAs currently occupy. METHODOLOGY/PRINCIPAL FINDINGS: Quantitatively extending the perception that PAs occupy "rock and ice", we show that across 147 nations PA networks are biased towards places that are unlikely to face land conversion pressures even in the absence of protection. We test each country's PA network for bias in elevation, slope, distances to roads and cities, and suitability for agriculture. Further, within each country's set of PAs, we also ask if the level of protection is biased in these ways. We find that the significant majority of national PA networks are biased to higher elevations, steeper slopes and greater distances to roads and cities. Also, within a country, PAs with higher protection status are more biased than are the PAs with lower protection statuses. CONCLUSIONS/SIGNIFICANCE: In sum, PAs are biased towards where they can least prevent land conversion (even if they offer perfect protection. These globally comprehensive results extend findings from nation-level analyses. They imply that siting rules such as the Convention on Biological Diversity's 2010 Target [to protect 10% of all ecoregions] might raise PA impacts if applied at the country level. In light of the potential for global carbon-based payments for avoided deforestation or REDD, these results suggest that attention to threat could improve outcomes from the creation and management of PAs.

  15. Observations and Models of Galaxy Assembly Bias

    Science.gov (United States)

    Campbell, Duncan A.

    2017-01-01

    The assembly history of dark matter haloes imparts various correlations between a halo’s physical properties and its large scale environment, i.e. assembly bias. It is common for models of the galaxy-halo connection to assume that galaxy properties are only a function of halo mass, implicitly ignoring how assembly bias may affect galaxies. Recently, programs to model and constrain the degree to which galaxy properties are influenced by assembly bias have been undertaken; however, the extent and character of galaxy assembly bias remains a mystery. Nevertheless, characterizing and modeling galaxy assembly bias is an important step in understanding galaxy evolution and limiting any systematic effects assembly bias may pose in cosmological measurements using galaxy surveys.I will present work on modeling and constraining the effect of assembly bias in two galaxy properties: stellar mass and star-formation rate. Conditional abundance matching allows for these galaxy properties to be tied to halo formation history to a variable degree, making studies of the relative strength of assembly bias possible. Galaxy-galaxy clustering and galactic conformity, the degree to which galaxy color is correlated between neighbors, are sensitive observational measures of galaxy assembly bias. I will show how these measurements can be used to constrain galaxy assembly bias and the peril of ignoring it.

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

    OpenAIRE

    Cheek, Lindsey

    2007-01-01

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

  17. Food, plant food, and vegetarian diets in the US dietary guidelines: conclusions of an expert panel.

    Science.gov (United States)

    Jacobs, David R; Haddad, Ella H; Lanou, Amy Joy; Messina, Mark J

    2009-05-01

    We summarize conclusions drawn from a panel discussion at the "Fifth International Congress on Vegetarian Nutrition" about the roles of and emphasis on food, plant food, and vegetarianism in current and future US dietary guidelines. The most general recommendation of the panel was that future dietary guidelines, following the lead of the 2005 Dietary Guidelines Advisory Committee, should emphasize food-based recommendations and thinking to the full extent that evidence allows. Although nutrient-based thinking and Dietary Reference Intakes (DRIs) may help ensure an adequate diet in the sense that deficiency states are avoided, the emphasis on DRIs may not capture many important nutritional issues and may inhibit a focus on foods. More generally, in the context of the conference on vegetarian nutrition, this report focuses on the history and structure of the Dietary Guidelines Advisory Committee, on various plant food-oriented recommendations that are supported by literature evidence, and on mechanisms for participating in the process of forming dietary guidelines. Among recommendations that likely would improve health and the environment, some are oriented toward increased plant food consumption and some toward vegetarianism. The literature on health effects of individual foods and whole lifestyle diets is insufficient and justifies a call for future food-oriented research, including expanding the evidence base for plant-based and vegetarian diets. The Dietary Guidelines Advisory Committee's role should be carried forward to creation of a publicly accessible icon (eg, the current pyramid) and related materials to ensure that the science base is fully translated for the public.

  18. Approach bias modification training and consumption: A review of the literature.

    Science.gov (United States)

    Kakoschke, Naomi; Kemps, Eva; Tiggemann, Marika

    2017-01-01

    Recent theoretical perspectives and empirical evidence have suggested that biased cognitive processing is an important contributor to unhealthy behaviour. Approach bias modification is a novel intervention in which approach biases for appetitive cues are modified. The current review of the literature aimed to evaluate the effectiveness of modifying approach bias for harmful consumption behaviours, including alcohol use, cigarette smoking, and unhealthy eating. Relevant publications were identified through a search of four electronic databases (PsycINFO, Google Scholar, ScienceDirect and Scopus) that were conducted between October and December 2015. Eligibility criteria included the use of a human adult sample, at least one session of avoidance training, and an outcome measure related to the behaviour of interest. The fifteen identified publications (comprising 18 individual studies) were coded on a number of characteristics, including consumption behaviour, participants, task, training and control conditions, number of training sessions and trials, outcome measure, and results. The results generally showed positive effects of approach-avoidance training, including reduced consumption behaviour in the laboratory, lower relapse rates, and improvements in self-reported measures of behaviour. Importantly, all studies (with one exception) that reported favourable consumption outcomes also demonstrated successful reduction of the approach bias for appetitive cues. Thus, the current review concluded that approach bias modification is effective for reducing both approach bias and unhealthy consumption behaviour.

  19. Testing for potential contextual bias effects during the verification stage of the ACE-V methodology when conducting fingerprint comparisons.

    Science.gov (United States)

    Langenburg, Glenn; Champod, Christophe; Wertheim, Pat

    2009-05-01

    This study was conducted to assess if fingerprint specialists could be influenced by extraneous contextual information during a verification process. Participants were separated into three groups: a control group (no contextual information was given), a low bias group (minimal contextual information was given in the form of a report prompting conclusions), and a high bias group (an internationally recognized fingerprint expert provided conclusions and case information to deceive this group into believing that it was his case and conclusions). A similar experiment was later conducted with laypersons. The results showed that fingerprint experts were influenced by contextual information during fingerprint comparisons, but not towards making errors. Instead, fingerprint experts under the biasing conditions provided significantly fewer definitive and erroneous conclusions than the control group. In contrast, the novice participants were more influenced by the bias conditions and did tend to make incorrect judgments, especially when prompted towards an incorrect response by the bias prompt.

  20. Forecasts: uncertain, inaccurate and biased?

    DEFF Research Database (Denmark)

    Nicolaisen, Morten Skou; Ambrasaite, Inga; Salling, Kim Bang

    2012-01-01

    Cost Benefit Analysis (CBA) is the dominating methodology for appraisal of transport infrastructure projects across the globe. In order to adequately assess the costs and benefits of such projects two types of forecasts are crucial to the validity of the appraisal. First are the forecasts...... accuracy of project benefits. This paper presents results from an on-going research project on uncertainties in transport project evaluation (UNITE) that find forecasts of demand to be not only uncertain, but at times also highly inaccurate and often displaying a concerning degree of bias. Demand for road...... projects appear to be systematically underestimated, while demand for rail projects appears to be systematically overestimated. We compare the findings in the present study with those of previous studies and discuss the implications for the validity of project appraisal in the form of CBA...

  1. Social reward shapes attentional biases.

    Science.gov (United States)

    Anderson, Brian A

    2016-01-01

    Paying attention to stimuli that predict a reward outcome is important for an organism to survive and thrive. When visual stimuli are associated with tangible, extrinsic rewards such as money or food, these stimuli acquire high attentional priority and come to automatically capture attention. In humans and other primates, however, many behaviors are not motivated directly by such extrinsic rewards, but rather by the social feedback that results from performing those behaviors. In the present study, I examine whether positive social feedback can similarly influence attentional bias. The results show that stimuli previously associated with a high probability of positive social feedback elicit value-driven attentional capture, much like stimuli associated with extrinsic rewards. Unlike with extrinsic rewards, however, such stimuli also influence task-specific motivation. My findings offer a potential mechanism by which social reward shapes the information that we prioritize when perceiving the world around us.

  2. Forecasts: uncertain, inaccurate and biased?

    DEFF Research Database (Denmark)

    Nicolaisen, Morten Skou; Ambrasaite, Inga; Salling, Kim Bang

    2012-01-01

    Cost Benefit Analysis (CBA) is the dominating methodology for appraisal of transport infrastructure projects across the globe. In order to adequately assess the costs and benefits of such projects two types of forecasts are crucial to the validity of the appraisal. First are the forecasts...... of construction costs, which account for the majority of total project costs. Second are the forecasts of travel time savings, which account for the majority of total project benefits. The latter of these is, inter alia, determined by forecasts of travel demand, which we shall use as a proxy for the forecasting...... accuracy of project benefits. This paper presents results from an on-going research project on uncertainties in transport project evaluation (UNITE) that find forecasts of demand to be not only uncertain, but at times also highly inaccurate and often displaying a concerning degree of bias. Demand for road...

  3. Estimation and correction of different flavors of surface observation biases in ensemble Kalman filter

    Science.gov (United States)

    Lorente-Plazas, Raquel; Hacker, Josua P.; Collins, Nancy; Lee, Jared A.

    2017-04-01

    The impact of assimilating surface observations has been shown in several publications, for improving weather prediction inside of the boundary layer as well as the flow aloft. However, the assimilation of surface observations is often far from optimal due to the presence of both model and observation biases. The sources of these biases can be diverse: an instrumental offset, errors associated to the comparison of point-based observations and grid-cell average, etc. To overcome this challenge, a method was developed using the ensemble Kalman filter. The approach consists on representing each observation bias as a parameter. These bias parameters are added to the forward operator and they extend the state vector. As opposed to the observation bias estimation approaches most common in operational systems (e.g. for satellite radiances), the state vector and parameters are simultaneously updated by applying the Kalman filter equations to the augmented state. The method to estimate and correct the observation bias is evaluated using observing system simulation experiments (OSSEs) with the Weather Research and Forecasting (WRF) model. OSSEs are constructed for the conventional observation network including radiosondes, aircraft observations, atmospheric motion vectors, and surface observations. Three different kinds of biases are added to 2-meter temperature for synthetic METARs. From the simplest to more sophisticated, imposed biases are: (1) a spatially invariant bias, (2) a spatially varying bias proportional to topographic height differences between the model and the observations, and (3) bias that is proportional to the temperature. The target region characterized by complex terrain is the western U.S. on a domain with 30-km grid spacing. Observations are assimilated every 3 hours using an 80-member ensemble during September 2012. Results demonstrate that the approach is able to estimate and correct the bias when it is spatially invariant (experiment 1). More

  4. Biased random walks on multiplex networks

    CERN Document Server

    Battiston, Federico; Latora, Vito

    2015-01-01

    Biased random walks on complex networks are a particular type of walks whose motion is biased on properties of the destination node, such as its degree. In recent years they have been exploited to design efficient strategies to explore a network, for instance by constructing maximally mixing trajectories or by sampling homogeneously the nodes. In multiplex networks, the nodes are related through different types of links (layers or communication channels), and the presence of connections at different layers multiplies the number of possible paths in the graph. In this work we introduce biased random walks on multiplex networks and provide analytical solutions for their long-term properties such as the stationary distribution and the entropy rate. We focus on degree-biased walks and distinguish between two subclasses of random walks: extensive biased walks consider the properties of each node separately at each layer, intensive biased walks deal instead with intrinsically multiplex variables. We study the effec...

  5. 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.

  6. Assessing the Bias in Communication Networks Sampled from Twitter

    CERN Document Server

    González-Bailón, Sandra; Rivero, Alejandro; Borge-Holthoefer, Javier; Moreno, Yamir

    2012-01-01

    We collect and analyse messages exchanged in Twitter using two of the platform's publicly available APIs (the search and stream specifications). We assess the differences between the two samples, and compare the networks of communication reconstructed from them. The empirical context is given by political protests taking place in May 2012: we track online communication around these protests for the period of one month, and reconstruct the network of mentions and re-tweets according to the two samples. We find that the search API over-represents the more central users and does not offer an accurate picture of peripheral activity; we also find that the bias is greater for the network of mentions. We discuss the implications of this bias for the study of diffusion dynamics and collective action in the digital era, and advocate the need for more uniform sampling procedures in the study of online communication.

  7. Public Values

    DEFF Research Database (Denmark)

    Beck Jørgensen, Torben; Rutgers, Mark R.

    2015-01-01

    administration is approached in terms of processes guided or restricted by public values and as public value creating: public management and public policy-making are both concerned with establishing, following and realizing public values. To study public values a broad perspective is needed. The article suggest......This article provides the introduction to a symposium on contemporary public values research. It is argued that the contribution to this symposium represent a Public Values Perspective, distinct from other specific lines of research that also use public value as a core concept. Public...... a research agenda for this encompasing kind of public values research. Finally the contributions to the symposium are introduced....

  8. Metacognition-augmented cognitive remediation training reduces jumping to conclusions and overconfidence but not neurocognitive deficits in psychosis.

    Science.gov (United States)

    Moritz, Steffen; Thoering, Teresa; Kühn, Simone; Willenborg, Bastian; Westermann, Stefan; Nagel, Matthias

    2015-01-01

    The majority of patients with schizophrenia display neurocognitive deficits (e.g., memory impairment) as well as inflated cognitive biases (e.g., jumping to conclusions). Both cognitive domains are implicated in the pathogenesis of the disorder and are known to compromise functional outcome. At present, there is a dearth of effective treatment options. A total of 90 patients with schizophrenia were recruited online (a diagnosis of schizophrenia had been confirmed in a large subgroup during a previous hospital admission). Subsequent to a baseline assessment encompassing psychopathology, self-reported cognition as well as objective memory and reasoning tests, patients were randomized to one of three conditions: standard cognitive remediation (mybraintraining), metacognition-augmented cognition remediation (CR) condition (variant of mybraintraining which encouraged patients to reduce speed of decision-making and attenuate response confidence when participants made high-confidence judgements and hasty incorrect decisions) and a waitlist control group. Patients were retested after 6 weeks and again 3 months after the second assessment. Groups did not differ on psychopathology and neurocognitive parameters at any timepoint. However, at follow-up the metacognitive-augmented CR group displayed a significant reduction on jumping to conclusions and overconfidence. Treatment adherence correlated with a reduction of depression; gains in the training exercises from the standard mybraintraining condition were correlated with improved objective memory performance. The study suggests that metacognition-augmented CR may ameliorate cognitive biases but not neurocognition. The study ties in well with prior research showing that neurocognitive dysfunctions are rather resistant to change; the failure to detect significant improvement of CR or metacognition-augmented CR on psychopathology and neurocognition over time may partly be attributed to a number of methodological limitations of

  9. Metacognition-augmented cognitive remediation training reduces jumping to conclusions and overconfidence but not neurocognitive deficits in psychosis

    Directory of Open Access Journals (Sweden)

    Steffen eMoritz

    2015-08-01

    Full Text Available The majority of patients with schizophrenia display neurocognitive deficits (e.g. memory deficits as well as inflated cognitive biases (e.g. jumping to conclusions. Both cognitive domains are implicated in the pathogenesis of the disorder and are known to compromise functional outcome. At present, there is a dearth of effective treatment options.A total of 90 patients with schizophrenia were recruited online (a diagnosis of schizophrenia had been confirmed in a large subgroup during a previous hospital admission. Subsequent to a baseline assessment encompassing psychopathology, self-reported cognition as well as objective memory and reasoning tests, patients were randomized to one of three conditions: standard cognitive remediation (mybraintraining, metacognition-augmented cognition remediation (CR condition (variant of mybraintraining which encouraged patients to reduce speed of decision-making and attenuate response confidence when they made high-confidence judgements and hasty incorrect decisions and a waitlist control group. Patients were retested after six weeks and again three months after the second assessment. Groups did not differ on psychopathology and neurocognitive parameters at any timepoint. However, at follow-up the metacognitive-augmented CR group displayed a significant reduction on jumping to conclusions and overconfidence. Treatment adherence correlated with a reduction of depression; gains in the training exercises from the standard mybraintraining condition were correlated with improved objective memory performance. The study suggests that metacognition-augmented CR may ameliorate cognitive biases but not neurocognition. The study ties in well with prior research showing that neurocognitive dysfunctions are rather resistant to change; the failure to detect significant improvement of CR or metacognition-augmented CR on psychopathology and neurocognition over time may partly be attributed to a number of methodological

  10. Political Accountability, Electoral Control, and Media Bias

    OpenAIRE

    Adachi, Takanori; Hizen, Yoichi

    2012-01-01

    Are anti-establishment mass media really useful in preventing politicians from behaving dishonestly? This paper proposes a voting model for analyzing how differences in the direction of media bias affect politicians' behavior. In particular, the probability of corruption by an incumbent is higher (than that in the case of no media bias) if and only if the mass media have some degree of "anti-incumbent" bias (i.e., information favorable to the incumbent is converted into unfavorable news about...

  11. Electric control of exchange bias training.

    Science.gov (United States)

    Echtenkamp, W; Binek, Ch

    2013-11-01

    Voltage-controlled exchange bias training and tunability are introduced. Isothermal voltage pulses are used to reverse the antiferromagnetic order parameter of magnetoelectric Cr(2)O(3), and thus continuously tune the exchange bias of an adjacent CoPd film. Voltage-controlled exchange bias training is initialized by tuning the antiferromagnetic interface into a nonequilibrium state incommensurate with the underlying bulk. Interpretation of these hitherto unreported effects contributes to new understanding in electrically controlled magnetism.

  12. Electric Control of Exchange Bias Training

    Science.gov (United States)

    Echtenkamp, W.; Binek, Ch.

    2013-11-01

    Voltage-controlled exchange bias training and tunability are introduced. Isothermal voltage pulses are used to reverse the antiferromagnetic order parameter of magnetoelectric Cr2O3, and thus continuously tune the exchange bias of an adjacent CoPd film. Voltage-controlled exchange bias training is initialized by tuning the antiferromagnetic interface into a nonequilibrium state incommensurate with the underlying bulk. Interpretation of these hitherto unreported effects contributes to new understanding in electrically controlled magnetism.

  13. When Do Children Exhibit a "Yes" Bias?

    Science.gov (United States)

    Okanda, Mako; Itakura, Shoji

    2010-01-01

    This study investigated whether one hundred and thirty-five 3- to 6-year-old children exhibit a yes bias to various yes-no questions and whether their knowledge status affects the production of a yes bias. Three-year-olds exhibited a yes bias to all yes-no questions such as "preference-object" and "knowledge-object" questions pertaining to…

  14. Revival of test bias research in preemployment testing.

    Science.gov (United States)

    Aguinis, Herman; Culpepper, Steven A; Pierce, Charles A

    2010-07-01

    We developed a new analytic proof and conducted Monte Carlo simulations to assess the effects of methodological and statistical artifacts on the relative accuracy of intercept- and slope-based test bias assessment. The main simulation design included 3,185,000 unique combinations of a wide range of values for true intercept- and slope-based test bias, total sample size, proportion of minority group sample size to total sample size, predictor (i.e., preemployment test scores) and criterion (i.e., job performance) reliability, predictor range restriction, correlation between predictor scores and the dummy-coded grouping variable (e.g., ethnicity), and mean difference between predictor scores across groups. Results based on 15 billion 925 million individual samples of scores and more than 8 trillion 662 million individual scores raise questions about the established conclusion that test bias in preemployment testing is nonexistent and, if it exists, it only occurs regarding intercept-based differences that favor minority group members. Because of the prominence of test fairness in the popular media, legislation, and litigation, our results point to the need to revive test bias research in preemployment testing.

  15. Primer design versus PCR bias in methylation independent PCR amplifications.

    Science.gov (United States)

    Wojdacz, Tomasz K; Borgbo, Tanni; Hansen, Lise Lotte

    2009-05-16

    Many protocols in methylation studies utilize one primer set to generate a PCR product from bisulfite modified template regardless of its methylation status (methylation independent amplification MIP). However, proportional amplification of methylated and unmethylated alleles is hard to achieve due to PCR bias favoring amplification of unmethylated relatively GC poor sequence. Two primer design systems have been proposed to overcome PCR bias in methylation independent amplifications. The first advises against including any CpG dinucleoteides into the primer sequence (CpG-free primers) and the second, recently published by us, is based on inclusion of a limited number of CpG sites into the primer sequence. Here we used the Methylation Sensitive High Resolution Melting (MS-HRM) technology to investigate the ability of primers designed according to both of the above mentioned primer design systems to proportionally amplify methylated and unmethylated templates. Ten "CpG-free" primer pairs and twenty primers containing limited number of CpGs were tested. In reconstruction experiments the "CpG-free" primers showed primer specific sensitivity and allowed us to detect methylation levels in the range from 5 to 50%. Whereas while using primers containing limited number of CpG sites we were able to consistently detect 1-0.1% methylation levels and effectively control PCR amplification bias. In conclusion, the primers with limited number of CpG sites are able to effectively reverse PCR bias and therefore detect methylated templates with significantly higher sensitivity than CpG free primers.

  16. Guidelines for reducing bias in nursing examinations.

    Science.gov (United States)

    Klisch, M L

    1994-01-01

    As our nation becomes more diversified, many schools of nursing strive to improve the recruitment and retention of English as a Second Language (ESL) and minority nursing students. An important aspect of this commitment to diversity is the reduction of biased items in nursing examinations, with the goal of making the evaluation process fair for all students. The author defines test and item bias, provides examples of biased items, and presents specific guidelines for decreasing item bias in teacher-made nursing examinations. A discussion of the related topic of whether ESL students should be given extended testing time is included.

  17. Bayesian long branch attraction bias and corrections.

    Science.gov (United States)

    Susko, Edward

    2015-03-01

    Previous work on the star-tree paradox has shown that Bayesian methods suffer from a long branch attraction bias. That work is extended to settings involving more taxa and partially resolved trees. The long branch attraction bias is confirmed to arise more broadly and an additional source of bias is found. A by-product of the analysis is methods that correct for biases toward particular topologies. The corrections can be easily calculated using existing Bayesian software. Posterior support for a set of two or more trees can thus be supplemented with corrected versions to cross-check or replace results. Simulations show the corrections to be highly effective.

  18. Attribution bias and social anxiety in schizophrenia

    Directory of Open Access Journals (Sweden)

    Amelie M. Achim

    2016-06-01

    Full Text Available Studies on attribution biases in schizophrenia have produced mixed results, whereas such biases have been more consistently reported in people with anxiety disorders. Anxiety comorbidities are frequent in schizophrenia, in particular social anxiety disorder, which could influence their patterns of attribution biases. The objective of the present study was thus to determine if individuals with schizophrenia and a comorbid social anxiety disorder (SZ+ show distinct attribution biases as compared with individuals with schizophrenia without social anxiety (SZ− and healthy controls. Attribution biases were assessed with the Internal, Personal, and Situational Attributions Questionnaire in 41 individual with schizophrenia and 41 healthy controls. Results revealed the lack of the normal externalizing bias in SZ+, whereas SZ− did not significantly differ from healthy controls on this dimension. The personalizing bias was not influenced by social anxiety but was in contrast linked with delusions, with a greater personalizing bias in individuals with current delusions. Future studies on attribution biases in schizophrenia should carefully document symptom presentation, including social anxiety.

  19. Implicit and Explicit Memory Bias in Opiate Dependent, Abstinent and Normal Individuals

    Directory of Open Access Journals (Sweden)

    Jafar Hasani

    2013-07-01

    Full Text Available Objective: The aim of current research was to assess implicit and explicit memory bias to drug related stimuli in opiate Dependent, abstinent and normal Individuals. Method: Three groups including opiate Dependent, abstinent and normal Individuals (n=25 were selected by available sampling method. After matching on the base of age, education level and type of substance use all participants assessed by recognition task (explicit memory bias and stem completion task (implicit memory bias. Results: The analysis of data showed that opiate dependent and abstinent groups in comparison with normal individual had implicit memory bias, whereas in explicit memory only opiate dependent individuals showed bias. Conclusion: The identification of explicit and implicit memory governing addiction may have practical implications in diagnosis, treatment and prevention of substance abuse.

  20. Scientific Opinion updating the risk assessment conclusions and risk management recommendations on the genetically modified insect resistant maize 1507

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Genetically Modified Organisms (GMO

    2012-10-01

    Full Text Available

    Following a request from the European Commission, the Panel on Genetically Modified Organisms of the European Food Safety Authority (EFSA GMO Panel compiled its previous risk assessment conclusions and risk management recommendations on the genetically modified insect resistant maize 1507, and considered their validity in the light of new relevant scientific publications published from 2005 onwards. The EFSA GMO Panel performed a search of the scientific literature published between 2005 and September 2012, and identified 61 peer-reviewed publications containing evidence specific to the risk assessment and/or management of maize 1507, of which two were relevant for the food and feed safety assessment, and 34 for the environmental risk assessment and/or risk management. None of these publications reported new information that would invalidate the previous conclusions on the safety of maize 1507 made by the EFSA GMO Panel. Therefore, the EFSA GMO Panel considers that its previous risk assessment conclusions on maize 1507, as well as its previous recommendations on risk mitigation measures and monitoring, remain valid and applicable.

  1. Overweight people have low levels of implicit weight bias, but overweight nations have high levels of implicit weight bias.

    Directory of Open Access Journals (Sweden)

    Maddalena Marini

    Full Text Available Although a greater degree of personal obesity is associated with weaker negativity toward overweight people on both explicit (i.e., self-report and implicit (i.e., indirect behavioral measures, overweight people still prefer thin people on average. We investigated whether the national and cultural context - particularly the national prevalence of obesity - predicts attitudes toward overweight people independent of personal identity and weight status. Data were collected from a total sample of 338,121 citizens from 71 nations in 22 different languages on the Project Implicit website (https://implicit.harvard.edu/ between May 2006 and October 2010. We investigated the relationship of the explicit and implicit weight bias with the obesity both at the individual (i.e., across individuals and national (i.e., across nations level. Explicit weight bias was assessed with self-reported preference between overweight and thin people; implicit weight bias was measured with the Implicit Association Test (IAT. The national estimates of explicit and implicit weight bias were obtained by averaging the individual scores for each nation. Obesity at the individual level was defined as Body Mass Index (BMI scores, whereas obesity at the national level was defined as three national weight indicators (national BMI, national percentage of overweight and underweight people obtained from publicly available databases. Across individuals, greater degree of obesity was associated with weaker implicit negativity toward overweight people compared to thin people. Across nations, in contrast, a greater degree of national obesity was associated with stronger implicit negativity toward overweight people compared to thin people. This result indicates a different relationship between obesity and implicit weight bias at the individual and national levels.

  2. The removal of multiplicative, systematic bias allows integration of breast cancer gene expression datasets – improving meta-analysis and prediction of prognosis

    Directory of Open Access Journals (Sweden)

    Pepper Stuart D

    2008-09-01

    Full Text Available Abstract Background The number of gene expression studies in the public domain is rapidly increasing, representing a highly valuable resource. However, dataset-specific bias precludes meta-analysis at the raw transcript level, even when the RNA is from comparable sources and has been processed on the same microarray platform using similar protocols. Here, we demonstrate, using Affymetrix data, that much of this bias can be removed, allowing multiple datasets to be legitimately combined for meaningful meta-analyses. Results A series of validation datasets comparing breast cancer and normal breast cell lines (MCF7 and MCF10A were generated to examine the variability between datasets generated using different amounts of starting RNA, alternative protocols, different generations of Affymetrix GeneChip or scanning hardware. We demonstrate that systematic, multiplicative biases are introduced at the RNA, hybridization and image-capture stages of a microarray experiment. Simple batch mean-centering was found to significantly reduce the level of inter-experimental variation, allowing raw transcript levels to be compared across datasets with confidence. By accounting for dataset-specific bias, we were able to assemble the largest gene expression dataset of primary breast tumours to-date (1107, from six previously published studies. Using this meta-dataset, we demonstrate that combining greater numbers of datasets or tumours leads to a greater overlap in differentially expressed genes and more accurate prognostic predictions. However, this is highly dependent upon the composition of the datasets and patient characteristics. Conclusion Multiplicative, systematic biases are introduced at many stages of microarray experiments. When these are reconciled, raw data can be directly integrated from different gene expression datasets leading to new biological findings with increased statistical power.

  3. The use of interim data and Data Monitoring Committee recommendations in randomized controlled trial reports: frequency, implications and potential sources of bias

    Directory of Open Access Journals (Sweden)

    Hampton John

    2008-03-01

    Full Text Available Abstract Background Interim analysis of accumulating trial data is important to protect participant safety during randomized controlled trials (RCTs. Data Monitoring Committees (DMCs often undertake such analyses, but their widening role may lead to extended use of interim analysis or recommendations that could potentially bias trial results. Methods Systematic search of eight major publications: Annals of Internal Medicine, BMJ, Circulation, CID, JAMA, JCO, Lancet and NEJM, including all randomised controlled trials (RCTs between June 2000 and May 2005 to identify RCTs that reported use of interim analysis, with or without DMC involvement. Recommendations made by the DMC or based on interim analysis were identified and potential sources of bias assessed. Independent double data extraction was performed on all included trials. Results We identified 1772 RCTs, of which 470 (27%; 470/1772 reported the use of a DMC and a further 116 (7%; 116/1772 trials reported some form of interim analysis without explicit mention of a DMC. There were 28 trials (24 with a formal DMC, randomizing a total of 79396 participants, identified as recommending changes to the trial that may have lead to biased results. In most of these, some form of sample size re-estimation was recommended with four trials also reporting changes to trial endpoints. The review relied on information reported in the primary publications and methods papers relating to the trials, higher rates of use may have occurred but not been reported. Conclusion The reported use of interim analysis and DMCs in clinical trials has been increasing in recent years. It is reassuring that in most cases recommendations were made in the interest of participant safety. However, in practice, recommendations that may lead to potentially biased trial results are being made.

  4. Zero-bias spin separation

    Science.gov (United States)

    Ganichev, Sergey D.; Bel'Kov, Vasily V.; Tarasenko, Sergey A.; Danilov, Sergey N.; Giglberger, Stephan; Hoffmann, Christoph; Ivchenko, Eougenious L.; Weiss, Dieter; Wegscheider, Werner; Gerl, Christian; Schuh, Dieter; Stahl, Joachim; de Boeck, Jo; Borghs, Gustaaf; Prettl, Wilhelm

    2006-09-01

    The generation, manipulation and detection of spin-polarized electrons in low-dimensional semiconductors are at the heart of spintronics. Pure spin currents, that is, fluxes of magnetization without charge current, are quite attractive in this respect. A paradigmatic example is the spin Hall effect, where an electrical current drives a transverse spin current and causes a non-equilibrium spin accumulation observed near the sample boundary. Here we provide evidence for an another effect causing spin currents which is fundamentally different from the spin Hall effect. In contrast to the spin Hall effect, it does not require an electric current to flow: without bias the spin separation is achieved by spin-dependent scattering of electrons in media with suitable symmetry. We show, by free-carrier absorption of terahertz (THz) radiation, that spin currents flow in a wide range of temperatures. Moreover, the experimental results provide evidence that simple electron gas heating by any means is already sufficient to yield spin separation due to spin-dependent energy-relaxation processes.

  5. Media bias under direct and indirect government control: when is the bias smaller?

    OpenAIRE

    Abhra Roy

    2015-01-01

    We present an analytical framework to compare media bias under direct and indirect government control. In this context, we show that direct control can lead to a smaller bias and higher welfare than indirect control. We further show that the size of the advertising market affects media bias only under direct control. Media bias, under indirect control, is not affected by the size of the advertising market.

  6. Anchoring and Publicity Effects in Clinical Judgment.

    Science.gov (United States)

    Friedlander, Myrna L.; Stockman, Susan J.

    1983-01-01

    Tested anchoring and publicity effects in clinicians' (N=46) successive judgments of detailed interview notes. Results indicated significant anchoring in one case suggesting a clinical bias. Public justification was related neither to subjects' ratings, to reported confidence in their ratings, nor differentially by case. (JAC)

  7. Pharmacogenomics Bias - Systematic distortion of study results by genetic heterogeneity

    Directory of Open Access Journals (Sweden)

    Zietemann, Vera

    2008-04-01

    trial. Results: We found four studies that systematically evaluated heterogeneity bias. All of them indicated that there is a potential of heterogeneity bias. However, none of these studies explicitly investigated the effect of genetic heterogeneity. Therefore, we performed our own simulation study. Our generic simulation showed that a purely HT-related bias is negative (conservative and a purely HP-related bias is positive (liberal. For many typical scenarios, the absolute bias is smaller than 10%. In case of joint HP and HT, the overall bias is likely triggered by the HP component and reaches positive values >100% if fractions of „fast progressors" and „strong treatment responders" are low. In the clinical example with pravastatin therapy, the unadjusted model overestimated the true life-years gained (LYG by 5.5% (1.07 LYG vs. 0.99 LYG for 56-year-old men. Conclusions: We have been able to predict the pharmacogenomics bias jointly caused by heterogeneity in progression of disease and heterogeneity in treatment response as a function of characteristics of patients, chronic disease, and treatment. In the case of joint presence of both types of heterogeneity, models ignoring this heterogeneity may generate results that overestimate the treatment benefit.

  8. Understanding Unconscious Bias and Unintentional Racism

    Science.gov (United States)

    Moule, Jean

    2009-01-01

    Unconscious biases affect one's relationships, whether they are fleeting relationships in airports or longer term relationships between teachers and students, teachers and parents, teachers and other educators. In this article, the author argues that understanding one's possible biases is essential for developing community in schools.…

  9. Belief biases and volatility of assets

    Science.gov (United States)

    Lei-Sun, Wen-Zou, Hui

    2014-10-01

    Based on an overlapping generation model, this paper introduces the noise traders with belief biases and rational traders. With an equilibrium analysis, this paper examines the volatility of risky asset. The results show that the belief biases, the probability of economy state, and the domain capability are all the factors that have effects on the volatility of the market.

  10. COVARIATION BIAS AND THE RETURN OF FEAR

    NARCIS (Netherlands)

    de Jong, Peter; VANDENHOUT, MA; MERCKELBACH, H

    1995-01-01

    Several studies have indicated that phobic fear is accompanied by a covariation bias, i.e. that phobic Ss tend to overassociate fear relevant stimuli and aversive outcomes. Such a covariation bias seems to be a fairly direct and powerful way to confirm danger expectations and enhance fear. Therefore

  11. Bounding the bias of contrastive divergence learning

    DEFF Research Database (Denmark)

    Fischer, Anja; Igel, Christian

    2011-01-01

    Optimization based on k-step contrastive divergence (CD) has become a common way to train restricted Boltzmann machines (RBMs). The k-step CD is a biased estimator of the log-likelihood gradient relying on Gibbs sampling. We derive a new upper bound for this bias. Its magnitude depends on k...

  12. Length-biased Weighted Maxwell Distribution

    Directory of Open Access Journals (Sweden)

    Kanak Modi

    2015-12-01

    Full Text Available The concept of length-biased distribution can be employed in development of proper models for life-time data. In this paper, we develop the length-biased form of Weighted Maxwell distribution (WMD. We study the statistical properties of the derived distribution including moments, moment generating function, hazard rate, reverse hazard rate, Shannon entropy and estimation of parameters

  13. Developmental Changes in the Whole Number Bias

    Science.gov (United States)

    Braithwaite, David W.; Siegler, Robert S.

    2017-01-01

    Many students' knowledge of fractions is adversely affected by whole number bias, the tendency to focus on the separate whole number components (numerator and denominator) of a fraction rather than on the fraction's integrated magnitude (ratio of numerator to denominator). Although whole number bias appears early in the fraction learning process…

  14. 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...

  15. Reducing status quo bias in choice experiments

    DEFF Research Database (Denmark)

    Bonnichsen, Ole; Ladenburg, Jacob

    2015-01-01

    to be superior, i.e. a status quo effect. However, in the 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 the Choice Experiment literature, status quo bias...

  16. 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:…

  17. On Measurement Bias in Causal Inference

    CERN Document Server

    Pearl, Judea

    2012-01-01

    This paper addresses the problem of measurement errors in causal inference and highlights several algebraic and graphical methods for eliminating systematic bias induced by such errors. In particulars, the paper discusses the control of partially observable confounders in parametric and non parametric models and the computational problem of obtaining bias-free effect estimates in such models.

  18. Understanding Implicit Bias: What Educators Should Know

    Science.gov (United States)

    Staats, Cheryl

    2016-01-01

    The desire to ensure the best for children is precisely why educators should become aware of the concept of implicit bias: the attitudes or stereotypes that affect our understanding, actions, and decisions in an unconscious manner. Operating outside of our conscious awareness, implicit biases are pervasive, and they can challenge even the most…

  19. 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:…

  20. Analysis of tag-position bias in MPSS technology

    Directory of Open Access Journals (Sweden)

    Rattray Magnus

    2006-04-01

    Full Text Available Abstract Background Massively Parallel Signature Sequencing (MPSS technology was recently developed as a high-throughput technology for measuring the concentration of mRNA transcripts in a sample. It has previously been observed that the position of the signature tag in a transcript (distance from 3' end can affect the measurement, but this effect has not been studied in detail. Results We quantify the effect of tag-position bias in Classic and Signature MPSS technology using published data from Arabidopsis, rice and human. We investigate the relationship between measured concentration and tag-position using nonlinear regression methods. The observed relationship is shown to be broadly consistent across different data sets. We find that there exist different and significant biases in both Classic and Signature MPSS data. For Classic MPSS data, genes with tag-position in the middle-range have highest measured abundance on average while genes with tag-position in the high-range, far from the 3' end, show a significant decrease. For Signature MPSS data, high-range tag-position genes tend to have a flatter relationship between tag-position and measured abundance. Thus, our results confirm that the Signature MPSS method fixes a substantial problem with the Classic MPSS method. For both Classic and Signature MPSS data there is a positive correlation between measured abundance and tag-position for low-range tag-position genes. Compared with the effects of mRNA length and number of exons, tag-position bias seems to be more significant in Arabadopsis. The tag-position bias is reflected both in the measured abundance of genes with a significant tag count and in the proportion of unexpressed genes identified. Conclusion Tag-position bias should be taken into consideration when measuring mRNA transcript abundance using MPSS technology, both in Classic and Signature MPSS methods.

  1. Market Efficiency and Behavioral Biases in the WNBA Betting Market

    Directory of Open Access Journals (Sweden)

    Rodney J. Paul

    2014-04-01

    Full Text Available The betting market for the Women’s National Basketball Association (WNBA is a thin financial market, which does not attract much interest from sports bettors. Given these characteristics, it is possible that profitable wagering strategies could exist for informed bettors of the WNBA. Using betting data on the WNBA from 2007–2012, we find that simple betting strategies do not earn statistically significant returns. WNBA bettors are like NBA bettors; however, in that they strongly prefer the best teams, particularly when they are on the road. Despite this clear bias, betting against the most popular public wagers is not found to earn statistically significant profits.

  2. Ascertainment bias in studies of human genome-wide polymorphism

    DEFF Research Database (Denmark)

    Clark, Andrew G.; Hubisz, Melissa J.; Bustamente, Carlos D.;

    2005-01-01

    of the SNPs that are found are influenced by the discovery sampling effort. The International HapMap project relied on nearly any piece of information available to identify SNPs-including BAC end sequences, shotgun reads, and differences between public and private sequences-and even made use of chimpanzee...... these studies. However, discrepancies persist, suggesting that the heterogeneity in the SNP discovery process of the HapMap project resulted in a data set resistant to complete ascertainment correction. Ascertainment bias will likely erode the power of tests of association between SNPs and complex disorders...

  3. Implicit Social Biases in People With Autism.

    Science.gov (United States)

    Birmingham, Elina; Stanley, Damian; Nair, Remya; Adolphs, Ralph

    2015-11-01

    Implicit social biases are ubiquitous and are known to influence social behavior. A core diagnostic criterion of autism spectrum disorders (ASD) is abnormal social behavior. We investigated the extent to which individuals with ASD might show a specific attenuation of implicit social biases, using Implicit Association Tests (IATs) involving social (gender, race) and nonsocial (nature, shoes) categories. High-functioning adults with ASD showed intact but reduced IAT effects relative to healthy control participants. We observed no selective attenuation of implicit social (vs. nonsocial) biases in our ASD population. To extend these results, we supplemented our healthy control data with data collected from a large online sample from the general population and explored correlations between autistic traits and IAT effects. We observed no systematic relationship between autistic traits and implicit social biases in our online and control samples. Taken together, these results suggest that implicit social biases, as measured by the IAT, are largely intact in ASD.

  4. Adaptive Variable Bias Magnetic Bearing Control

    Science.gov (United States)

    Johnson, Dexter; Brown, Gerald V.; Inman, Daniel J.

    1998-01-01

    Most magnetic bearing control schemes use a bias current with a superimposed control current to linearize the relationship between the control current and the force it delivers. With the existence of the bias current, even in no load conditions, there is always some power consumption. In aerospace applications, power consumption becomes an important concern. In response to this concern, an alternative magnetic bearing control method, called Adaptive Variable Bias Control (AVBC), has been developed and its performance examined. The AVBC operates primarily as a proportional-derivative controller with a relatively slow, bias current dependent, time-varying gain. The AVBC is shown to reduce electrical power loss, be nominally stable, and provide control performance similar to conventional bias control. Analytical, computer simulation, and experimental results are presented in this paper.

  5. Are all biases missing data problems?

    Science.gov (United States)

    Howe, Chanelle J; Cain, Lauren E; Hogan, Joseph W

    2015-09-01

    Estimating causal effects is a frequent goal of epidemiologic studies. Traditionally, there have been three established systematic threats to consistent estimation of causal effects. These three threats are bias due to confounders, selection, and measurement error. Confounding, selection, and measurement bias have typically been characterized as distinct types of biases. However, each of these biases can also be characterized as missing data problems that can be addressed with missing data solutions. Here we describe how the aforementioned systematic threats arise from missing data as well as review methods and their related assumptions for reducing each bias type. We also link the assumptions made by the reviewed methods to the missing completely at random (MCAR) and missing at random (MAR) assumptions made in the missing data framework that allow for valid inferences to be made based on the observed, incomplete data.

  6. Composite biasing in Monte Carlo radiative transfer

    CERN Document Server

    Baes, Maarten; Lunttila, Tuomas; Bianchi, Simone; Camps, Peter; Juvela, Mika; Kuiper, Rolf

    2016-01-01

    Biasing or importance sampling is a powerful technique in Monte Carlo radiative transfer, and can be applied in different forms to increase the accuracy and efficiency of simulations. One of the drawbacks of the use of biasing is the potential introduction of large weight factors. We discuss a general strategy, composite biasing, to suppress the appearance of large weight factors. We use this composite biasing approach for two different problems faced by current state-of-the-art Monte Carlo radiative transfer codes: the generation of photon packages from multiple components, and the penetration of radiation through high optical depth barriers. In both cases, the implementation of the relevant algorithms is trivial and does not interfere with any other optimisation techniques. Through simple test models, we demonstrate the general applicability, accuracy and efficiency of the composite biasing approach. In particular, for the penetration of high optical depths, the gain in efficiency is spectacular for the spe...

  7. Eulerian bias and the galaxy density field

    CERN Document Server

    Mann, B M; Heavens, A F; Mann, Bob; Peacock, John; Heavens, Alan

    1997-01-01

    We investigate the effects on cosmological clustering statistics of empirical biasing, where the galaxy distribution is a local transformation of the present-day Eulerian density field. The effects of the suppression of galaxy numbers in voids, and their enhancement in regions of high density, are considered, independently and in combination. We compare results from numerical simulations with the predictions of simple analytic models. We find that the bias is generally scale-dependent, so that the shape of the galaxy power spectrum differs from that of the underlying mass distribution. The degree of bias is always a monotonic function of scale, tending to an asymptotic value on scales where the density fluctuations are linear. The scale dependence is often rather weak, with many reasonable prescriptions giving a bias which is nearly independent of scale. We have investigated whether such an Eulerian bias can reconcile a range of theoretical power spectra with the twin requirements of fitting the galaxy power ...

  8. Sampling Bias on Cup Anemometer Mean Winds

    Science.gov (United States)

    Kristensen, L.; Hansen, O. F.; Højstrup, J.

    2003-10-01

    The cup anemometer signal can be sampled in several ways to obtain the mean wind speed. Here we discuss the sampling of series of mean wind speeds from consecutive rotor rotations, followed by unweighted and weighted averaging. It is shown that the unweighted averaging creates a positive bias on the long-term mean wind speed, which is at least one order of magnitude larger than the positive bias from the weighted averaging, also known as the sample-and-hold method. For a homogeneous, neutrally stratified flow the first biases are 1%-2%. For comparison the biases due to fluctuations of the three wind velocity components and due to calibration non-linearity are determined under the same conditions. The largest of these is the v-bias from direction fluctuations. The calculations pertain to the Risø P2546A model cup anemometer.

  9. "Care Drain". Explaining Bias in Theorizing Women's Migration

    Directory of Open Access Journals (Sweden)

    Speranta Dumitru

    2016-12-01

    Full Text Available Migrant women are often stereotyped. Some scholars associate the feminization of migration with domestic work and criticize the “care drain” as a new form of imperialism that the First World imposes on the Third World. However, migrant women employed as domestic workers in Northern America and Europe represent only 2% of migrant women worldwide and cannot be seen as characterizing the “feminization of migration”. Why are migrant domestic workers overestimated? This paper explores two possible sources of bias. The first is sampling: conclusions about “care drain” are often generalized from small samples of domestic workers. The second stems from the affect heuristic: imagining children left behind by migrant mothers provokes strong feelings of injustice which trump other considerations. The paper argues that neither source of bias is unavoidable and finds evidence of gender stereotypes in the “care drain” construal

  10. WeBIAS: a web server for publishing bioinformatics applications.

    Science.gov (United States)

    Daniluk, Paweł; Wilczyński, Bartek; Lesyng, Bogdan

    2015-11-02

    One of the requirements for a successful scientific tool is its availability. Developing a functional web service, however, is usually considered a mundane and ungratifying task, and quite often neglected. When publishing bioinformatic applications, such attitude puts additional burden on the reviewers who have to cope with poorly designed interfaces in order to assess quality of presented methods, as well as impairs actual usefulness to the scientific community at large. In this note we present WeBIAS-a simple, self-contained solution to make command-line programs accessible through web forms. It comprises a web portal capable of serving several applications and backend schedulers which carry out computations. The server handles user registration and authentication, stores queries and results, and provides a convenient administrator interface. WeBIAS is implemented in Python and available under GNU Affero General Public License. It has been developed and tested on GNU/Linux compatible platforms covering a vast majority of operational WWW servers. Since it is written in pure Python, it should be easy to deploy also on all other platforms supporting Python (e.g. Windows, Mac OS X). Documentation and source code, as well as a demonstration site are available at http://bioinfo.imdik.pan.pl/webias . WeBIAS has been designed specifically with ease of installation and deployment of services in mind. Setting up a simple application requires minimal effort, yet it is possible to create visually appealing, feature-rich interfaces for query submission and presentation of results.

  11. Public lighting.

    NARCIS (Netherlands)

    Schreuder, D.A.

    1986-01-01

    The function of public lighting and the relationship between public lighting and accidents are considered briefly as aspects of effective countermeasures. Research needs and recent developments in installation and operational described. Public lighting is an efficient accident countermeasure, but

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

    Science.gov (United States)

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

    2014-10-01

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

  13. ROBIS: A new tool to assess risk of bias in systematic reviews was developed

    Science.gov (United States)

    Whiting, Penny; Savović, Jelena; Higgins, Julian P.T.; Caldwell, Deborah M.; Reeves, Barnaby C.; Shea, Beverley; Davies, Philippa; Kleijnen, Jos; Churchill, Rachel

    2016-01-01

    Objective To develop ROBIS, a new tool for assessing the risk of bias in systematic reviews (rather than in primary studies). Study Design and Setting We used four-stage approach to develop ROBIS: define the scope, review the evidence base, hold a face-to-face meeting, and refine the tool through piloting. Results ROBIS is currently aimed at four broad categories of reviews mainly within health care settings: interventions, diagnosis, prognosis, and etiology. The target audience of ROBIS is primarily guideline developers, authors of overviews of systematic reviews (“reviews of reviews”), and review authors who might want to assess or avoid risk of bias in their reviews. The tool is completed in three phases: (1) assess relevance (optional), (2) identify concerns with the review process, and (3) judge risk of bias. Phase 2 covers four domains through which bias may be introduced into a systematic review: study eligibility criteria; identification and selection of studies; data collection and study appraisal; and synthesis and findings. Phase 3 assesses the overall risk of bias in the interpretation of review findings and whether this considered limitations identified in any of the phase 2 domains. Signaling questions are included to help judge concerns with the review process (phase 2) and the overall risk of bias in the review (phase 3); these questions flag aspects of review design related to the potential for bias and aim to help assessors judge risk of bias in the review process, results, and conclusions. Conclusions ROBIS is the first rigorously developed tool designed specifically to assess the risk of bias in systematic reviews. PMID:26092286

  14. On the power of the test for cluster bias

    NARCIS (Netherlands)

    Jak, S.; Oort, F.J.

    2015-01-01

    Cluster bias refers to measurement bias with respect to the clustering variable in multilevel data. The absence of cluster bias implies absence of bias with respect to any cluster-level (level 2) variable. The variables that possibly cause the bias do not have to be measured to test for cluster

  15. Exchange bias effect in alloys and compounds.

    Science.gov (United States)

    Giri, S; Patra, M; Majumdar, S

    2011-02-23

    The phenomenology of exchange bias effects observed in structurally single-phase alloys and compounds but composed of a variety of coexisting magnetic phases such as ferromagnetic, antiferromagnetic, ferrimagnetic, spin-glass, cluster-glass and disordered magnetic states are reviewed. The investigations on exchange bias effects are discussed in diverse types of alloys and compounds where qualitative and quantitative aspects of magnetism are focused based on macroscopic experimental tools such as magnetization and magnetoresistance measurements. Here, we focus on improvement of fundamental issues of the exchange bias effects rather than on their technological importance.

  16. 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...

  17. Quantum Statistical Calculation of Exchange Bias

    Institute of Scientific and Technical Information of China (English)

    WANG Huai-Yu; DAI Zhen-Hong

    2004-01-01

    The phenomenon of exchange bias of ferromagnetic (FM) films, which are coupled with an antiferromagnetic (AFM) film, is studied by Heisenberg model by use of the many-body Green's function method of quantum statistical theory for the uncompensated case. Exchange bias HE and coercivity Hc are calculated as functions of the FM film thickness L, temperature, the strength of the exchange interaction across the interface between FM and AFM and the anisotropy of the FM. Hc decreases with increasing L when the FM film is beyond some thickness. The dependence of the exchange bias HE on the FM film thickness and on temperature is also qualitatively in agreement with experiments.

  18. Removing Malmquist bias from linear regressions

    Science.gov (United States)

    Verter, Frances

    1993-01-01

    Malmquist bias is present in all astronomical surveys where sources are observed above an apparent brightness threshold. Those sources which can be detected at progressively larger distances are progressively more limited to the intrinsically luminous portion of the true distribution. This bias does not distort any of the measurements, but distorts the sample composition. We have developed the first treatment to correct for Malmquist bias in linear regressions of astronomical data. A demonstration of the corrected linear regression that is computed in four steps is presented.

  19. Forecast Bias Correction: A Second Order Method

    CERN Document Server

    Crowell, Sean

    2010-01-01

    The difference between a model forecast and actual observations is called forecast bias. This bias is due to either incomplete model assumptions and/or poorly known parameter values and initial/boundary conditions. In this paper we discuss a method for estimating corrections to parameters and initial conditions that would account for the forecast bias. A set of simple experiments with the logistic ordinary differential equation is performed using an iterative version of a first order version of our method to compare with the second order version of the method.

  20. 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.

  1. Evaluation of the FERA study on bumble bees and consideration of its potential impact on the EFSA conclusions on neonicotinoids

    Directory of Open Access Journals (Sweden)

    European Food Safety Authority

    2013-06-01

    Full Text Available The European Food Safety Authority was requested to clarify whether the new publication on the effects of neonicotinoid seed treatments on bumble bee colonies under field conditions (March, 2013; Thompson et al. has an impact on the EFSA Conclusions on the three neonicotinoids clothianidin, thiamethoxam and imidacloprid (EFSA Journal 2013;11(1:3066; EFSA Journal 2013;11(1:3067; EFSA Journal 2013;11(1:3068. The Conclusions on neonicotinoids, published on 16 January 2013, did not permit to perform a risk assessment for bumble bees and identified the need for further information to address the risk to pollinators other than honey bees. The conclusions of this scientific statement were reached on the basis of the evaluation of the study report by Thompson et al. (2013,and additional raw data made available by the study authors to EFSA. The study investigated the exposure of bumble bee colonies placed in the vicinity of crops treated with neonicotinoids and its major effects on bumble bee colonies. The current assessment concluded that, due to the weaknesses of the study design and methodology, the study did not allow to draw any conclusion on the effects of neonicotinoids on exposed bumble bee colonies, and confirmed that the outcome of the conclusions drawn for the three neonicotinoid insecticides remains unchanged.

  2. Conclusions of the commission: property transfer of natural gas transport networks; Conclusions de la commission: transfert de propriete des reseaux de transport de gaz naturel

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-05-01

    This document deals with the evolution of the avoidance of the natural gas transport allowances and their transfers modalities. The first part recalls the juridical, technical and economical situation and the european context taking into account by the commission in this project. The commission choices of the evaluation methods are then presented. The evaluations and the conclusions of the commission are presented in the last part. (A.L.B.)

  3. Public Broadcasting.

    Science.gov (United States)

    Shooshan, Harry M.; Arnheim, Louise

    This paper, the second in a series exploring future options for public policy in the communications and information arenas, examines some of the issues underlying public broadcasting, primarily public television. It advances two reasons why quality local public television programming is scarce: funds for the original production of programming have…

  4. Popularity, similarity, and the network extraversion bias.

    Science.gov (United States)

    Feiler, Daniel C; Kleinbaum, Adam M

    2015-05-01

    Using the emergent friendship network of an incoming cohort of students in an M.B.A. program, we examined the role of extraversion in shaping social networks. Extraversion has two important implications for the emergence of network ties: a popularity effect, in which extraverts accumulate more friends than introverts do, and a homophily effect, in which the more similar are two people's levels of extraversion, the more likely they are to become friends. These effects result in a systematic network extraversion bias, in which people's social networks will tend to be overpopulated with extraverts and underpopulated with introverts. Moreover, the most extraverted people have the greatest network extraversion bias, and the most introverted people have the least network extraversion bias. Our finding that social networks were systematically misrepresentative of the broader social environment raises questions about whether there is a societal bias toward believing other people are more extraverted than they actually are and whether introverts are better socially calibrated than extraverts.

  5. Neurocognition and cognitive biases in schizophrenia.

    Science.gov (United States)

    Garcia, Cristina P; Sacks, Stephanie A; Weisman de Mamani, Amy G

    2012-08-01

    Individuals with schizophrenia have been found to exhibit a number of information processing biases that may play a role in the development and exacerbation of symptoms and may impair overall functioning. However, little is known about the factors that are associated with these cognitive biases. Recently, researchers have begun to consider whether neurocognitive deficits, common in schizophrenia, may be risk factors for the development of cognitive biases. In the present study, we assessed neurocognition (verbal learning, delayed verbal recall memory, and verbal recognition memory) and cognitive biases (knowledge corruption and impaired cognitive insight) in 72 individuals with schizophrenia or schizoaffective disorder. As hypothesized, poorer delayed verbal recall memory was associated with increased knowledge corruption. Contrary to expectations, verbal learning and verbal memory were not associated with cognitive insight. These findings suggest that an inadequate recall memory system may put patients with schizophrenia at greater risk for cognitive distortions.

  6. Accounting for Unobservable Exposure Time Bias Wh...

    Data.gov (United States)

    U.S. Department of Health & Human Services — Accounting for Unobservable Exposure Time Bias When Using Medicare Prescription Drug Data Unobservable exposure time is common among Medicare Part D beneficiaries,...

  7. Fixed points of occasionally weakly biased mappings

    Directory of Open Access Journals (Sweden)

    Y. Mahendra Singh, M. R. Singh

    2012-09-01

    Full Text Available Common fixed point results due to Pant et al. [Pant et al., Weak reciprocal continuity and fixed point theorems, Ann Univ Ferrara, 57(1, 181-190 (2011] are extended to a class of non commuting operators called occasionally weakly biased pair[ N. Hussain, M. A. Khamsi A. Latif, Commonfixed points for JH-operators and occasionally weakly biased pairs under relaxed conditions, Nonlinear Analysis, 74, 2133-2140 (2011]. We also provideillustrative examples to justify the improvements. Abstract. Common fixed point results due to Pant et al. [Pant et al., Weakreciprocal continuity and fixed point theorems, Ann Univ Ferrara, 57(1, 181-190 (2011] are extended to a class of non commuting operators called occasionally weakly biased pair[ N. Hussain, M. A. Khamsi A. Latif, Common fixed points for JH-operators and occasionally weakly biased pairs under relaxed conditions, Nonlinear Analysis, 74, 2133-2140 (2011]. We also provide illustrative examples to justify the improvements.

  8. Bias Modeling for Distantly Supervised Relation Extraction

    Directory of Open Access Journals (Sweden)

    Yang Xiang

    2015-01-01

    Full Text Available Distant supervision (DS automatically annotates free text with relation mentions from existing knowledge bases (KBs, providing a way to alleviate the problem of insufficient training data for relation extraction in natural language processing (NLP. However, the heuristic annotation process does not guarantee the correctness of the generated labels, promoting a hot research issue on how to efficiently make use of the noisy training data. In this paper, we model two types of biases to reduce noise: (1 bias-dist to model the relative distance between points (instances and classes (relation centers; (2 bias-reward to model the possibility of each heuristically generated label being incorrect. Based on the biases, we propose three noise tolerant models: MIML-dist, MIML-dist-classify, and MIML-reward, building on top of a state-of-the-art distantly supervised learning algorithm. Experimental evaluations compared with three landmark methods on the KBP dataset validate the effectiveness of the proposed methods.

  9. Reducing hypothetical bias in choice experiments

    DEFF Research Database (Denmark)

    Ladenburg, Jacob; Olsen, Søren Bøye; Nielsen, Rasmus Christian Fejer

    Hypothetical bias in stated preference studies is an essential problem which reduces the validity of the obtained welfare estimates for non-market goods. In the attempt to mitigate hypothetical bias, a type of reminder known as Cheap Talk, has been applied in previous studies and found to overall...... eliminate some of the hypothetical bias. The present paper tests an addition to Cheap Talk, an Opt-Out Reminder. The Opt-Out Reminder is an objective short script presented prior to the choice sets, prompting the respondent to choose the opt-out alternative, if he/she finds the proposed policy generated...... alternatives in a choice set too expensive. The results suggest that adding an Opt-Out Reminder to Cheap Talk can in fact reduce hypothetical bias even further and reduces some of the ineffectiveness of CT in relation to the survey bid range and experienced respondents....

  10. Autobiographical memory bias in social anxiety.

    Science.gov (United States)

    Krans, Julie; de Bree, June; Bryant, Richard A

    2014-01-01

    In social anxiety the psychological self is closely related to the feared stimulus. Socially anxious individuals are, by definition, concerned about how the self is perceived and evaluated by others. As autobiographical memory is strongly related to views of the self it follows that biases in autobiographical memory play an important role in social anxiety. In the present study high (n = 19) and low (n = 29) socially anxious individuals were compared on autobiographical memory bias, current goals, and self-discrepancy. Individuals high in social anxiety showed a bias towards recalling more negative and more social anxiety-related autobiographical memories, reported more current goals related to overcoming social anxiety, and showed larger self-discrepancies. The pattern of results is largely in line with earlier research in individuals with PTSD and complicated grief. This suggests that the relation between autobiographical memory bias and the self is a potentially valuable trans-diagnostic factor.

  11. Statistical framework for estimating GNSS bias

    CERN Document Server

    Vierinen, Juha; Rideout, William C; Erickson, Philip J; Norberg, Johannes

    2015-01-01

    We present a statistical framework for estimating global navigation satellite system (GNSS) non-ionospheric differential time delay bias. The biases are estimated by examining differences of measured line integrated electron densities (TEC) that are scaled to equivalent vertical integrated densities. The spatio-temporal variability, instrumentation dependent errors, and errors due to inaccurate ionospheric altitude profile assumptions are modeled as structure functions. These structure functions determine how the TEC differences are weighted in the linear least-squares minimization procedure, which is used to produce the bias estimates. A method for automatic detection and removal of outlier measurements that do not fit into a model of receiver bias is also described. The same statistical framework can be used for a single receiver station, but it also scales to a large global network of receivers. In addition to the Global Positioning System (GPS), the method is also applicable to other dual frequency GNSS s...

  12. Pseudo exchange bias due to rotational anisotropy

    Energy Technology Data Exchange (ETDEWEB)

    Ehrmann, A., E-mail: andrea.ehrmann@fh-bielefeld.de [Faculty of Engineering and Mathematics, Bielefeld University of Applied Sciences, 33619 Bielefeld (Germany); Komraus, S.; Blachowicz, T.; Domino, K. [Institute of Physics – Center for Science and Education, Silesian University of Technology, 44-100 Gliwice (Poland); Nees, M.K.; Jakobs, P.J.; Leiste, H. [Karlsruhe Nano Micro Facility (KNMF), Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen (Germany); Mathes, M.; Schaarschmidt, M. [ACCESS e. V., 57072 Aachen (Germany)

    2016-08-15

    Ferromagnetic nanostructure arrays with particle dimensions between 160 nm and 400 nm were created by electron-beam lithography. The permalloy structures consist of rectangular-shaped walls around a square open space. While measuring their magnetic properties using the Magneto-Optical Kerr Effect (MOKE), in some angular regions an exchange bias (EB) seemed to appear. This paper gives an overview of possible reasons for this “pseudo exchange bias” and shows experimentally and by means of micromagnetic simulations that this effect can be attributed to unintentionally measuring minor loops. - Highlights: • Pseudo exchange bias can be found in square Py nanorings of different dimensions. • Pseudo exchange bias stems from unintentionally measuring minor loops. • New approach in explaining “real” exchange bias effect in coupled FM/AFM systems. • Theoretical base to explain other measurements of a rotational anisotropy.

  13. Affective forecasting bias in preschool children.

    Science.gov (United States)

    Gautam, Shalini; Bulley, Adam; von Hippel, William; Suddendorf, Thomas

    2017-07-01

    Adults are capable of predicting their emotional reactions to possible future events. Nevertheless, they systematically overestimate the intensity of their future emotional reactions relative to how they feel when these events actually occur. The developmental origin of this "intensity bias" has not yet been examined. Two studies were conducted to test the intensity bias in preschool children. In the first study, 5-year-olds (N=30) predicted how they would feel if they won or lost various games. Comparisons with subsequent self-reported feelings indicated that participants overestimated how sad they would feel to lose the games but did not overestimate their happiness from winning. The second study replicated this effect in another sample of 5-year-olds (n=34) and also found evidence of an intensity bias in 4-year-olds (n=30). These findings provide the first evidence of a negative intensity bias in affective forecasting among young children. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. A meta-analysis of gender stereotypes and bias in experimental simulations of employment decision making.

    Science.gov (United States)

    Koch, Amanda J; D'Mello, Susan D; Sackett, Paul R

    2015-01-01

    Gender bias continues to be a concern in many work settings, leading researchers to identify factors that influence workplace decisions. In this study we examine several of these factors, using an organizing framework of sex distribution within jobs (including male- and female-dominated jobs as well as sex-balanced, or integrated, jobs). We conducted random effects meta-analyses including 136 independent effect sizes from experimental studies (N = 22,348) and examined the effects of decision-maker gender, amount and content of information available to the decision maker, type of evaluation, and motivation to make careful decisions on gender bias in organizational decisions. We also examined study characteristics such as type of participant, publication year, and study design. Our findings revealed that men were preferred for male-dominated jobs (i.e., gender-role congruity bias), whereas no strong preference for either gender was found for female-dominated or integrated jobs. Second, male raters exhibited greater gender-role congruity bias than did female raters for male-dominated jobs. Third, gender-role congruity bias did not consistently decrease when decision makers were provided with additional information about those they were rating, but gender-role congruity bias was reduced when information clearly indicated high competence of those being evaluated. Fourth, gender-role congruity bias did not differ between decisions that required comparisons among ratees and decisions made about individual ratees. Fifth, decision makers who were motivated to make careful decisions tended to exhibit less gender-role congruity bias for male-dominated jobs. Finally, for male-dominated jobs, experienced professionals showed smaller gender-role congruity bias than did undergraduates or working adults.

  15. Preference-Inconsistent Recommendations: An Effective Approach for Reducing Confirmation Bias and Stimulating Divergent Thinking?

    Science.gov (United States)

    Schwind, Christina; Buder, Jurgen; Cress, Ulrike; Hesse, Friedrich W.

    2012-01-01

    The Web is a perfect backdrop for opinion formation as a multitude of different opinions is publicly available. However, the different opinions often remain unexploited: Learners prefer preference-consistent over preference-inconsistent information, a phenomenon called confirmation bias. Two experiments were designed to test whether technologies…

  16. Recall Bias in Childhood Atopic Diseases Among Adults in The Odense Adolescence Cohort Study

    DEFF Research Database (Denmark)

    Mortz, Charlotte G; Andersen, Klaus E; Bindslev-Jensen, Carsten

    2015-01-01

    Atopic dermatitis (AD) is a common disease in childhood and an important risk factor for the later development of other atopic diseases. Many publications on childhood AD use questionnaires based on information obtained in adulthood, which introduce the possibility of recall bias. In a prospectiv...

  17. Time-Lag Bias in Trials of Pediatric Antidepressants: A Systematic Review and Meta-Analysis

    Science.gov (United States)

    Reyes, Magdalena M.; Panza, Kaitlyn E.; Martin, Andres; Bloch, Michael H.

    2011-01-01

    Objective: To determine whether there is evidence of a time-lag bias in the publication of pediatric antidepressant trials. Method: We conducted a meta-analysis of published and unpublished randomized placebo-controlled trials of serotonin reuptake inhibitors (SRIs) in subjects less than 18 years of age with major depressive disorder. Our main…

  18. Time-Lag Bias in Trials of Pediatric Antidepressants: A Systematic Review and Meta-Analysis

    Science.gov (United States)

    Reyes, Magdalena M.; Panza, Kaitlyn E.; Martin, Andres; Bloch, Michael H.

    2011-01-01

    Objective: To determine whether there is evidence of a time-lag bias in the publication of pediatric antidepressant trials. Method: We conducted a meta-analysis of published and unpublished randomized placebo-controlled trials of serotonin reuptake inhibitors (SRIs) in subjects less than 18 years of age with major depressive disorder. Our main…

  19. Write when hot - Submit when not: seasonal bias in peer review or acceptance?

    NARCIS (Netherlands)

    Shalvi, S.; Baas, M.; Handgraaf, M.J.J.; de Dreu, C.K.W.

    2010-01-01

    At a top psychology journal, Psychological Science (PS), submissions peak during the summer months. We tested whether this seasonal submission bias decreases the likelihood of a paper being accepted in that period. Month of submission data was obtained for all 575 publications in PS for the period

  20. Write when hot - Submit when not: seasonal bias in peer review or acceptance?

    NARCIS (Netherlands)

    Shalvi, S.; Baas, M.; Handgraaf, M.J.J.; de Dreu, C.K.W.

    2010-01-01

    At a top psychology journal, Psychological Science (PS), submissions peak during the summer months. We tested whether this seasonal submission bias decreases the likelihood of a paper being accepted in that period. Month of submission data was obtained for all 575 publications in PS for the period 2

  1. Information bias in contingent valuation: effects of personal relevance, quality of information, and motivational orientation

    Science.gov (United States)

    Icek Ajzen; Thomas C. Brown; Lori H. Rosenthal

    1996-01-01

    A laboratory experiment examined the potential for information bias in contingent valuation (CV). Consistent with the view that information about a public or private good can function as a persuasive communication, willingness to pay (WTP) was found to increase with the quality of arguments used to describe the good, especially under conditions of high personal...

  2. Learned value and object perception: Accelerated perception or biased decisions?

    Science.gov (United States)

    Rajsic, Jason; Perera, Harendri; Pratt, Jay

    2017-02-01

    Learned value is known to bias visual search toward valued stimuli. However, some uncertainty exists regarding the stage of visual processing that is modulated by learned value. Here, we directly tested the effect of learned value on preattentive processing using temporal order judgments. Across four experiments, we imbued some stimuli with high value and some with low value, using a nonmonetary reward task. In Experiment 1, we replicated the value-driven distraction effect, validating our nonmonetary reward task. Experiment 2 showed that high-value stimuli, but not low-value stimuli, exhibit a prior-entry effect. Experiment 3, which reversed the temporal order judgment task (i.e., reporting which stimulus came second), showed no prior-entry effect, indicating that although a response bias may be present for high-value stimuli, they are still reported as appearing earlier. However, Experiment 4, using a simultaneity judgment task, showed no shift in temporal perception. Overall, our results support the conclusion that learned value biases perceptual decisions about valued stimuli without speeding preattentive stimulus processing.

  3. Implicit Social Biases in People With Autism

    OpenAIRE

    2015-01-01

    Implicit social biases are ubiquitous and are known to influence social behavior. A core diagnostic criterion of autism spectrum disorders (ASD) is abnormal social behavior. We investigated the extent to which individuals with ASD might show a specific attenuation of implicit social biases, using Implicit Association Tests (IATs) involving social (gender, race) and nonsocial (nature, shoes) categories. High-functioning adults with ASD showed intact but reduced IAT effects relative to healthy ...

  4. Biased liquid crystal photonic bandgap fiber

    DEFF Research Database (Denmark)

    Weirich, Johannes; Lægsgaard, Jesper; Alkeskjold, Thomas Tanggaard

    2008-01-01

    We simulate the director structure of all capillaries in a biased photonic crystal fiber infiltrated with liquid crystals. Various mode simulations for different capillaries show the necessity to consider the entire structure.......We simulate the director structure of all capillaries in a biased photonic crystal fiber infiltrated with liquid crystals. Various mode simulations for different capillaries show the necessity to consider the entire structure....

  5. Sex-Biased Parent-Offspring Conflict

    OpenAIRE

    Redondo, T.; Gomendio, Montserrat; Medina, Rosario

    1992-01-01

    In species showing sexual dimorphism, parents may obtain different fitness returns per unit of parental expenditure from sons and daughters. Under these circumstances, parents are expected to invest extra resources in offspring of the most profitable sex. However, it is unclear whether sex-biased expenditure is the result of selection acting on parents, their offspring, or both. Current parent-offspring conflict theory is used to investigate whether sex biases in parental expenditure should b...

  6. SUBJECTIVE AGE BIASES AMONG ADOLESCENT GIRLS

    OpenAIRE

    Guiot, Denis

    2000-01-01

    International audience; Until now, the concept of subjective age has only been used to segment the mature market. Research on consumer behavior has shown the effects of a youthful bias, the tendency to see oneself as younger. Using a conceptual framework based on self-concept, social comparison, and symbolic consumption, this research proposes to characterize the antecedents and the effects of an analogous but opposed tendency: an older bias among adolescent girls. An empirical study carried ...

  7. Measuring the bias of technological change

    OpenAIRE

    Doraszelski, Ulrich; Jaumandreu, Jordi

    2014-01-01

    Technological change can increase the productivity of the various factors of production in equal terms or it can be biased towards a specific factor. We develop an estimator for production functions when productivity is multi-dimensional. We directly assess the bias of technological change by measuring, at the level of the individual firm, how much of it is factor neutral and how much is labor augmenting. Applying our estimator to panel data from Spain, we find that technological change is in...

  8. Perceptual and performance biases in action selection

    OpenAIRE

    2008-01-01

    When we see an object in the world, there may be a large number of different ways to interact with that object. This large 'visuomotor space' can be constrained through affordances (perceptually available object properties defining potential uses), task demands and the actor's intentions. The effects of perceptual biases can be modified by performance factors, such as a limb's end-state-comfort (ESC; Rosenbaum et al. 1990). We investigated how two other potential performance biases affected i...

  9. Measuring Population Health Using Electronic Health Records: Exploring Biases and Representativeness in a Community Health Information Exchange.

    Science.gov (United States)

    Dixon, Brian E; Gibson, P Joseph; Frederickson Comer, Karen; Rosenman, Marc

    2015-01-01

    Assessment is a core function of public health. Comprehensive clinical data may enhance community health assessment by providing up-to-date, representative data for use in public health programs and policies, especially when combined with community-level data relevant to social determinants. In this study we examine routinely collected and geospatially-enhanced EHR data to assess population health at various levels of geographic granularity available from a regional health information exchange. We present preliminary findings and discuss important biases in EHR data. Future work is needed to develop methods for correcting for those biases to support routine epidemiology work of public health.

  10. IEEE Conference Publications in Libraries.

    Science.gov (United States)

    Johnson, Karl E.

    1984-01-01

    Conclusions of surveys (63 libraries, OCLC database, University of Rhode Island users) assessing handling of Institute of Electrical and Electronics Engineers (IEEE) conference publications indicate that most libraries fully catalog these publications using LC cataloging, and library patrons frequently require series access to publications. Eight…

  11. IEEE Conference Publications in Libraries.

    Science.gov (United States)

    Johnson, Karl E.

    1984-01-01

    Conclusions of surveys (63 libraries, OCLC database, University of Rhode Island users) assessing handling of Institute of Electrical and Electronics Engineers (IEEE) conference publications indicate that most libraries fully catalog these publications using LC cataloging, and library patrons frequently require series access to publications. Eight…

  12. Constraints on Assembly Bias from Galaxy Clustering

    CERN Document Server

    Zentner, Andrew R; Bosch, Frank C van den; Lange, Johannes U; Villarreal, Antonio

    2016-01-01

    We constrain the newly-introduced decorated Halo Occupation Distribution (HOD) model using SDSS DR7 measurements of projected galaxy clustering or r-band luminosity threshold samples. The decorated HOD is a model for the galaxy-halo connection that augments the HOD by allowing for the possibility of galaxy assembly bias: galaxy luminosity may be correlated with dark matter halo properties besides mass, Mvir. We demonstrate that it is not possible to rule out galaxy assembly bias using DR7 measurements of galaxy clustering alone. Moreover, galaxy samples with Mr < -20 and Mr < -20.5 favor strong central galaxy assembly bias. These samples prefer scenarios in which high-concentration are more likely to host a central galaxy relative to low-concentration halos of the same mass. We exclude zero assembly bias with high significance for these samples. Satellite galaxy assembly bias is significant for the faintest sample, Mr < -19. We find no evidence for assembly bias in the Mr < -21 sample. Assembly bi...

  13. Neural correlates of attentional bias in addiction.

    Science.gov (United States)

    Hester, Robert; Luijten, Maartje

    2014-06-01

    A small but growing neuroimaging literature has begun to examine the neural mechanisms underlying the difficulty that substance-use dependent (SUD) groups have with ignoring salient, drug-related stimuli. Drug-related attentional bias appears to implicate the countermanding forces of cognitive control and reward salience. Basic cognitive neuroscience research suggests that ignoring emotionally evocative stimuli in our environment requires both up-regulation of control networks and down-regulation of processing in emotion and reward regions. Research to date suggests that attentional biases for drug-related stimuli emerge from a failure to sufficiently increase control of attention over salient, but task-irrelevant stimuli. While SUD samples have typically shown increased activity in the cognitive control regions (ie, lateral prefrontal and dorsal anterior cingulate), during attentional bias such increases appear to have been insufficient for the concomitant increases in processing by the emotion/reward regions (ie, amygdala, insula, and striatum). Given the potential contribution of attentional biases to perpetuating drug use and the development of interventions (both pharmaceutical and cognitive-behavioral) to treat biases, understanding the neural basis of successfully reducing bias remains an important, but as yet unanswered, question for our field.

  14. Publication outcomes for research presented at a Canadian surgical conference

    Science.gov (United States)

    Crawford, Sean A.; Roche-Nagle, Graham

    2017-01-01

    Background The failure of investigators to publish research in peer-reviewed journals following acceptance at a national or international meeting can lead to significant publication biases in the literature. Our objective was to evaluate the abstract to manuscript conversion rate for abstracts presented at the Canadian Society for Vascular Surgery (CSVS) annual meeting and to evaluate the conversion rate for CSVS-awarded research grants. Methods We searched for authors of abstracts accepted at the CSVS Annual Meeting (2007–2013) and recipients of CSVS research awards (2005–2013) on Scopus and PubMed databases to identify related publications. Results We identified 84 publications from 188 research abstracts (45%) and 17 publications from 39 research grants (44%). The mean time to publication was 1.8 years and the mean impact factor was 2.7. Studies related to endovascular therapies demonstrated a trend toward a higher rate of publication relative to open surgical therapies (64 [56%] v. 37 [27%]). Additionally, we observed a similar trend in research grant topics related to endovascular therapies relative to open surgical therapies (9 [67%] v. 8 [38%]). Finally, CSVS research grant recipients who subsequently published had a significantly higher h-index at the time of receipt than those who had not published. Conclusion The CSVS annual meeting’s abstract to publication conversion rate is comparable to that of its Canadian peers as well as to other medical specialties; however, a substantial publication gap remains. We identified several potential areas that may help to improve the effectiveness of CSVS research grants. PMID:28234220

  15. The Public Sector in the Czech Republic in Light of the Public Choice Theory

    National Research Council Canada - National Science Library

    Václav Rybáček

    2016-01-01

    .... The results are discussed against the theoretical background of the public choice theory. It was found out that there was an obvious bias to the deficit-driven provision of the public goods reflected concurrently in the growing indebtedness. On the other hand, the share of total revenues and expenditures remains rather stable over time.

  16. Comparison of conditional bias-adjusted estimators for interim analysis in clinical trials with survival data.

    Science.gov (United States)

    Shimura, Masashi; Gosho, Masahiko; Hirakawa, Akihiro

    2017-02-17

    Group sequential designs are widely used in clinical trials to determine whether a trial should be terminated early. In such trials, maximum likelihood estimates are often used to describe the difference in efficacy between the experimental and reference treatments; however, these are well known for displaying conditional and unconditional biases. Established bias-adjusted estimators include the conditional mean-adjusted estimator (CMAE), conditional median unbiased estimator, conditional uniformly minimum variance unbiased estimator (CUMVUE), and weighted estimator. However, their performances have been inadequately investigated. In this study, we review the characteristics of these bias-adjusted estimators and compare their conditional bias, overall bias, and conditional mean-squared errors in clinical trials with survival endpoints through simulation studies. The coverage probabilities of the confidence intervals for the four estimators are also evaluated. We find that the CMAE reduced conditional bias and showed relatively small conditional mean-squared errors when the trials terminated at the interim analysis. The conditional coverage probability of the conditional median unbiased estimator was well below the nominal value. In trials that did not terminate early, the CUMVUE performed with less bias and an acceptable conditional coverage probability than was observed for the other estimators. In conclusion, when planning an interim analysis, we recommend using the CUMVUE for trials that do not terminate early and the CMAE for those that terminate early. Copyright © 2017 John Wiley & Sons, Ltd.

  17. A note on the expected biases in conventional iterative health state valuation protocols.

    Science.gov (United States)

    Ternent, Laura; Tsuchiya, Aki

    2013-05-01

    Typical health state valuation exercises use tradeoff methods, such as the time tradeoff or the standard gamble, involving a series of iterated questions so that a value for each health state by each individual respondent is elicited. This iterative process is a source of potential biases, but this has not received much attention in the health state valuation literature. The issue has been researched widely in the contingent valuation (CV) literature, which elicits the monetary value of hypothetical outcomes. The lessons learned in the CV literature are revisited in the context of the design and administration of health state valuations. The article introduces the main known biases in the CV literature and then examines how each might affect conventional iterative health state valuations. Of the 8 main types of biases, starting point bias, range bias, and incentive incompatibility bias are found to be potentially relevant. Furthermore, the magnitude and direction of the bases are unlikely to be uniform and depend on the range of the value (e.g., between 0 and 0.5). Limitation. This is an overview article, and the conclusions drawn need to be tested empirically. Health state valuation studies, like CV studies, are susceptible to a number of possible biases that affect the resulting values. Their magnitude and direction are unlikely to be uniform, and thus empirical studies are needed to diagnose the problem and, if necessary, to address it.

  18. Understanding Pretrial Publicity: Predecisional Distortion of Evidence by Mock Jurors

    Science.gov (United States)

    Hope, Lorraine; Memon, Amina; McGeorge, Peter

    2004-01-01

    Prejudicial pretrial publicity (PTP) constitutes a serious source of juror bias. The current study examined differences in predecisional distortion for mock jurors exposed to negative PTP (N-PTP) versus nonexposed control participants. According to work by K. A. Carlson and J. E. Russo (2001), predecisional distortion occurs when jurors bias new…

  19. Analysis of codon usage and nucleotide composition bias in polioviruses

    Directory of Open Access Journals (Sweden)

    Gu Yuan-xing

    2011-03-01

    Full Text Available Abstract Background Poliovirus, the causative agent of poliomyelitis, is a human enterovirus and a member of the family of Picornaviridae and among the most rapidly evolving viruses known. Analysis of codon usage can reveal much about the molecular evolution of the viruses. However, little information about synonymous codon usage pattern of polioviruses genome has been acquired to date. Methods The relative synonymous codon usage (RSCU values, effective number of codon (ENC values, nucleotide contents and dinucleotides were investigated and a comparative analysis of codon usage pattern for open reading frames (ORFs among 48 polioviruses isolates including 31 of genotype 1, 13 of genotype 2 and 4 of genotype 3. Results The result shows that the overall extent of codon usage bias in poliovirus samples is low (mean ENC = 53.754 > 40. The general correlation between base composition and codon usage bias suggests that mutational pressure rather than natural selection is the main factor that determines the codon usage bias in those polioviruses. Depending on the RSCU data, it was found that there was a significant variation in bias of codon usage among three genotypes. Geographic factor also has some effect on the codon usage pattern (exists in the genotype-1 of polioviruses. No significant effect in gene length or vaccine derived polioviruses (DVPVs, wild viruses and live attenuated virus was observed on the variations of synonymous codon usage in the virus genes. The relative abundance of dinucleotide (CpG in the ORFs of polioviruses are far below expected values especially in DVPVs and attenuated virus of polioviruses genotype 1. Conclusion The information from this study may not only have theoretical value in understanding poliovirus evolution, especially for DVPVs genotype 1, but also have potential value for the development of poliovirus vaccines.

  20. Attention bias for paranoia-relevant visual stimuli in schizophrenia.

    Science.gov (United States)

    Moritz, Steffen; Laudan, Anna

    2007-09-01

    A number of studies indicate that patients with schizophrenia share a bias for paranoia-relevant material. The presence of an attentional bias for such stimuli would be of utter importance for our pathogenetic understanding of the disorder in view of ample evidence that patients with schizophrenia gather little information before arriving at strong conclusions: A both scarce and affectively biased data selection of available information may heavily distort its inner representation and thus prompt the formation of false beliefs. To date, the profile of this putative attentional bias in schizophrenia (e.g., automatic vs. controlled; hypervigilance towards vs. problems to disengage from such stimuli) is not fully uncovered. To shed light on this aspect of information processing in schizophrenia, we administered a novel task based on the inhibition of return paradigm (IOR). Twenty-four schizophrenia patients and thirty-four healthy controls were presented neutral (e.g., cup), anxiety-relevant (e.g., shark), and paranoia-relevant cue pictures (e.g., gun) at either of two possible locations. Subsequent to either a short or long interval, a target appeared at the same or opposite location. Participants were requested to press a spatially corresponding button. Both currently paranoid and nonparanoid schizophrenia patients responded faster to all kinds of targets following paranoia-relevant pictures, that is, such stimuli speeded reaction times irrespective of the cue-target interval and spatial correspondence. This indicates that paranoia-relevant information generally alerts patients more than other stimuli and facilitates processing of subsequent information. Possible implications of this finding for our understanding of delusion formation and maintenance are outlined.

  1. Inferring Master Painters' Esthetic Biases from the Statistics of Portraits

    Science.gov (United States)

    Aleem, Hassan; Correa-Herran, Ivan; Grzywacz, Norberto M.

    2017-01-01

    The Processing Fluency Theory posits that the ease of sensory information processing in the brain facilitates esthetic pleasure. Accordingly, the theory would predict that master painters should display biases toward visual properties such as symmetry, balance, and moderate complexity. Have these biases been occurring and if so, have painters been optimizing these properties (fluency variables)? Here, we address these questions with statistics of portrait paintings from the Early Renaissance period. To do this, we first developed different computational measures for each of the aforementioned fluency variables. Then, we measured their statistics in 153 portraits from 26 master painters, in 27 photographs of people in three controlled poses, and in 38 quickly snapped photographs of individual persons. A statistical comparison between Early Renaissance portraits and quickly snapped photographs revealed that painters showed a bias toward balance, symmetry, and moderate complexity. However, a comparison between portraits and controlled-pose photographs showed that painters did not optimize each of these properties. Instead, different painters presented biases toward different, narrow ranges of fluency variables. Further analysis suggested that the painters' individuality stemmed in part from having to resolve the tension between complexity vs. symmetry and balance. We additionally found that constraints on the use of different painting materials by distinct painters modulated these fluency variables systematically. In conclusion, the Processing Fluency Theory of Esthetic Pleasure would need expansion if we were to apply it to the history of visual art since it cannot explain the lack of optimization of each fluency variables. To expand the theory, we propose the existence of a Neuroesthetic Space, which encompasses the possible values that each of the fluency variables can reach in any given art period. We discuss the neural mechanisms of this Space and propose that it

  2. Inferring Master Painters' Esthetic Biases from the Statistics of Portraits.

    Science.gov (United States)

    Aleem, Hassan; Correa-Herran, Ivan; Grzywacz, Norberto M

    2017-01-01

    The Processing Fluency Theory posits that the ease of sensory information processing in the brain facilitates esthetic pleasure. Accordingly, the theory would predict that master painters should display biases toward visual properties such as symmetry, balance, and moderate complexity. Have these biases been occurring and if so, have painters been optimizing these properties (fluency variables)? Here, we address these questions with statistics of portrait paintings from the Early Renaissance period. To do this, we first developed different computational measures for each of the aforementioned fluency variables. Then, we measured their statistics in 153 portraits from 26 master painters, in 27 photographs of people in three controlled poses, and in 38 quickly snapped photographs of individual persons. A statistical comparison between Early Renaissance portraits and quickly snapped photographs revealed that painters showed a bias toward balance, symmetry, and moderate complexity. However, a comparison between portraits and controlled-pose photographs showed that painters did not optimize each of these properties. Instead, different painters presented biases toward different, narrow ranges of fluency variables. Further analysis suggested that the painters' individuality stemmed in part from having to resolve the tension between complexity vs. symmetry and balance. We additionally found that constraints on the use of different painting materials by distinct painters modulated these fluency variables systematically. In conclusion, the Processing Fluency Theory of Esthetic Pleasure would need expansion if we were to apply it to the history of visual art since it cannot explain the lack of optimization of each fluency variables. To expand the theory, we propose the existence of a Neuroesthetic Space, which encompasses the possible values that each of the fluency variables can reach in any given art period. We discuss the neural mechanisms of this Space and propose that it

  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. Designing a biased specification-based subjective test of image quality

    Science.gov (United States)

    Reibman, Amy R.

    2015-03-01

    Specification-based subjective tests (SBSTs) form the basis for almost all performance analysis of image and video quality estimators (QEs). Our ability to compare the efficacy of different QEs across a wide range of applications depends on careful design of these SBST, so the conclusions that are drawn about how well a QE performs are reliable and accurate. In this paper, we explore methods to design biased SBSTs for image and video QEs. A biased SBST will produce an estimate of the performance of a given QE that is systematically different than its actual performance. We demonstrate by proof of concept that it's possible to create SBSTs that generate misleading or biased Pearson or Spearman correlation coefficients between subjective and objective scores, and we present some diagnostics that begin to evaluate when influential observations have been included in the SBST. Understanding how to create biased tests is a first step toward the overall goal of creating more effective unbiased SBSTs.

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

    DEFF Research Database (Denmark)

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

    2011-01-01

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

  6. 20 CFR 220.112 - Conclusions by physicians concerning the claimant's disability.

    Science.gov (United States)

    2010-04-01

    ... claimant's impairment must result from anatomical, physiological, or psychological abnormalities which are... are not within the expertise of medical sources. (b) Medical opinions that are conclusive. A...

  7. The importance of isomorphism for conclusions about homology: A Bayesian multilevel structural equation modeling approach with ordinal indicators

    Directory of Open Access Journals (Sweden)

    Nigel eGuenole

    2016-03-01

    Full Text Available We describe a Monte Carlo study examining the impact of assuming item isomorphism (i.e., equivalent construct meaning across levels of analysis on conclusions about homology (i.e., equivalent structural relations across levels of analysis under varying degrees of non-isomorphism in the context of ordinal indicator multilevel structural equation models (MSEMs. We focus on the condition where one or more loadings are higher on the between level than on the within level to show that while much past research on homology has ignored the issue of psychometric isomorphism, psychometric isomorphism is in fact critical to valid conclusions about homology. More specifically, when a measurement model with non-isomorphic items occupies an exogenous position in a multilevel structural model and the non-isomorphism of these items is not modeled, the within level exogenous latent variance is under-estimated leading to over-estimation of the within level structural coefficient, while the between level exogenous latent variance is overestimated leading to underestimation of the between structural coefficient. When a measurement model with non-isomorphic items occupies an endogenous position in a multilevel structural model and the non-isomorphism of these items is not modeled, the endogenous within level latent variance is under-estimated leading to under-estimation of the within level structural coefficient while the endogenous between level latent variance is over-estimated leading to over-estimation of the between level structural coefficient. The innovative aspect of this article is demonstrating that even minor violations of psychometric isomorphism render claims of homology untenable. We also show that posterior predictive p-values for ordinal indicator Bayesian MSEMs are insensitive to violations of isomorphism even when they lead to severely biased within and between level structural parameters. We highlight conditions where poor estimation of even

  8. The Importance of Isomorphism for Conclusions about Homology: A Bayesian Multilevel Structural Equation Modeling Approach with Ordinal Indicators.

    Science.gov (United States)

    Guenole, Nigel

    2016-01-01

    We describe a Monte Carlo study examining the impact of assuming item isomorphism (i.e., equivalent construct meaning across levels of analysis) on conclusions about homology (i.e., equivalent structural relations across levels of analysis) under varying degrees of non-isomorphism in the context of ordinal indicator multilevel structural equation models (MSEMs). We focus on the condition where one or more loadings are higher on the between level than on the within level to show that while much past research on homology has ignored the issue of psychometric isomorphism, psychometric isomorphism is in fact critical to valid conclusions about homology. More specifically, when a measurement model with non-isomorphic items occupies an exogenous position in a multilevel structural model and the non-isomorphism of these items is not modeled, the within level exogenous latent variance is under-estimated leading to over-estimation of the within level structural coefficient, while the between level exogenous latent variance is overestimated leading to underestimation of the between structural coefficient. When a measurement model with non-isomorphic items occupies an endogenous position in a multilevel structural model and the non-isomorphism of these items is not modeled, the endogenous within level latent variance is under-estimated leading to under-estimation of the within level structural coefficient while the endogenous between level latent variance is over-estimated leading to over-estimation of the between level structural coefficient. The innovative aspect of this article is demonstrating that even minor violations of psychometric isomorphism render claims of homology untenable. We also show that posterior predictive p-values for ordinal indicator Bayesian MSEMs are insensitive to violations of isomorphism even when they lead to severely biased within and between level structural parameters. We highlight conditions where poor estimation of even correctly specified

  9. On the Need for Quantitative Bias Analysis in the Peer-Review Process.

    Science.gov (United States)

    Fox, Matthew P; Lash, Timothy L

    2017-05-15

    Peer review is central to the process through which epidemiologists generate evidence to inform public health and medical interventions. Reviewers thereby act as critical gatekeepers to high-quality research. They are asked to carefully consider the validity of the proposed work or research findings by paying careful attention to the methodology and critiquing the importance of the insight gained. However, although many have noted problems with the peer-review system for both manuscripts and grant submissions, few solutions have been proposed to improve the process. Quantitative bias analysis encompasses all methods used to quantify the impact of systematic error on estimates of effect in epidemiologic research. Reviewers who insist that quantitative bias analysis be incorporated into the design, conduct, presentation, and interpretation of epidemiologic research could substantially strengthen the process. In the present commentary, we demonstrate how quantitative bias analysis can be used by investigators and authors, reviewers, funding agencies, and editors. By utilizing quantitative bias analysis in the peer-review process, editors can potentially avoid unnecessary rejections, identify key areas for improvement, and improve discussion sections by shifting from speculation on the impact of sources of error to quantification of the impact those sources of bias may have had. © The Author 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Jumping to conclusions style along the continuum of delusions: delusion-prone individuals are not hastier in decision making than healthy individuals.

    Directory of Open Access Journals (Sweden)

    Suzanne Ho-wai So

    Full Text Available Literature comparing 'jumping to conclusions' (JTC between patients and healthy controls has demonstrated the importance of the reasoning bias in the development of delusions. When groups that vary along the entire delusional continuum are included, the relationship between JTC and delusionality is less clear. This study compared JTC and delusional dimensions between 28 patients with delusions, 35 delusion-prone individuals and 32 non-delusion-prone individuals. Delusion proneness was defined by an established threshold based on the Peters et al. Delusions Inventory. Two versions of the beads task (85:15 and 60:40 were used to measure JTC. As hypothesized, patients manifested hastier data gathering than the two non-clinical groups on both beads tasks. However, delusion-prone individuals did not manifest a hastier decision making style than non-delusion prone individuals. Instead, non-delusion-prone participants showed more JTC bias than delusion-prone individuals on the easier beads task. There was no evidence for a dose-response relationship between JTC and delusional dimensions, with correlations between JTC and PDI scores found in the non-delusion-prone group only. The present finding confirms the link between an extreme JTC bias and the presence of clinical delusions, and argues against a linear relationship between JTC and delusionality along the symptomatic continuum.

  11. “Fair Play”: A Videogame Designed to Address Implicit Race Bias Through Active Perspective Taking

    Science.gov (United States)

    Kaatz, Anna; Chu, Sarah; Ramirez, Dennis; Samson-Samuel, Clem; Carnes, Molly

    2014-01-01

    Abstract Objective: Having diverse faculty in academic health centers will help diversify the healthcare workforce and reduce health disparities. Implicit race bias is one factor that contributes to the underrepresentation of Black faculty. We designed the videogame “Fair Play” in which players assume the role of a Black graduate student named Jamal Davis. As Jamal, players experience subtle race bias while completing “quests” to obtain a science degree. We hypothesized that participants randomly assigned to play the game would have greater empathy for Jamal and lower implicit race bias than participants randomized to read narrative text describing Jamal's experience. Materials and Methods: University of Wisconsin–Madison graduate students were recruited via e-mail and randomly assigned to play “Fair Play” or read narrative text through an online link. Upon completion, participants took an Implicit Association Test to measure implicit bias and answered survey questions assessing empathy toward Jamal and awareness of bias. Results: As hypothesized, gameplayers showed the least implicit bias but only when they also showed high empathy for Jamal (P=0.013). Gameplayers did not show greater empathy than text readers, and women in the text condition reported the greatest empathy for Jamal (P=0.008). However, high empathy only predicted lower levels of implicit bias among those who actively took Jamal's perspective through gameplay (P=0.014). Conclusions: A videogame in which players experience subtle race bias as a Black graduate student has the potential to reduce implicit bias, possibly because of a game's ability to foster empathy through active perspective taking. PMID:26192644

  12. On the relative independence of thinking biases and cognitive ability.

    Science.gov (United States)

    Stanovich, Keith E; West, Richard F

    2008-04-01

    In 7 different studies, the authors observed that a large number of thinking biases are uncorrelated with cognitive ability. These thinking biases include some of the most classic and well-studied biases in the heuristics and biases literature, including the conjunction effect, framing effects, anchoring effects, outcome bias, base-rate neglect, "less is more" effects, affect biases, omission bias, myside bias, sunk-cost effect, and certainty effects that violate the axioms of expected utility theory. In a further experiment, the authors nonetheless showed that cognitive ability does correlate with the tendency to avoid some rational thinking biases, specifically the tendency to display denominator neglect, probability matching rather than maximizing, belief bias, and matching bias on the 4-card selection task. The authors present a framework for predicting when cognitive ability will and will not correlate with a rational thinking tendency.

  13. 'One mission accomplished, more important ones remain': commentary on Every-Palmer, S., Howick, J. (2014) How evidence-based medicine is failing due to biased trials and selective publication. Journal of Evaluation in Clinical Practice, 20 (6), 908-914.

    Science.gov (United States)

    Wyer, Peter; da Silva, Suzana Alves

    2015-06-01

    Every-Palmer and Howick suggest that evidence-based medicine (EBM) is failing in its mission because of contamination of research by manufacturer and researcher-motivated bias and self-interest. They fail to define that mission and to distinguish between the EBM movement and the research enterprise it was developed to critique. An educational movement, EBM accomplished its mission to simplify and package clinical epidemiological concepts in a form accessible to clinical learners. Its wide adoption within educational circles fostered critical literacy among several generations of practitioners. Illumination of bias, subterfuge and incomplete reporting of research has been a strength of EBM. Increased uptake and use of clinical research within the health care system properly defines the failing mission that eludes Every-Palmer and Howick. Responsibility for failure to make progress towards its achievement is shared by virtually all relevant streams within the system, including policy, clinical guideline development, educational movements and the development of approaches to evidence synthesis. Discordance between the epistemological premises pervading today's research and health care community and the complex social processes that ultimately determine research use constitutes an important factor that must be addressed as part of a remedy. Enhanced emphasis on and demonstration of alternative approaches to research such as realism and realist synthesis and the momentum towards development of a learning health care system hold promise as guideposts for the rapidly evolving health care environment. © 2015 John Wiley & Sons, Ltd.

  14. Perspectives on Prediction Variance and Bias in Developing, Assessing, and Comparing Experimental Designs

    Energy Technology Data Exchange (ETDEWEB)

    Piepel, Gregory F.

    2010-12-01

    The vast majority of response surface methods used in practice to develop, assess, and compare experimental designs focus on variance properties of designs. Because response surface models only approximate the true unknown relationships, models are subject to bias errors as well as variance errors. Beginning with the seminal paper of Box and Draper (1959) and over the subsequent 50 years, methods that consider bias and mean-squared-error (variance and bias) properties of designs have been presented in the literature. However, these methods are not widely implemented in software and are not routinely used to develop, assess, and compare experimental designs in practice. Methods for developing, assessing, and comparing response surface designs that account for variance properties are reviewed. Brief synopses of publications that consider bias or mean-squared-error properties are provided. The difficulties and approaches for addressing bias properties of designs are summarized. Perspectives on experimental design methods that account for bias and/or variance properties and on future needs are presented.

  15. Public Schools

    Data.gov (United States)

    Department of Homeland Security — This Public Schools feature dataset is composed of all Public elementary and secondary education in the United States as defined by the Common Core of Data, National...

  16. Diffusion versus linear ballistic accumulation: different models but the same conclusions about psychological processes?

    NARCIS (Netherlands)

    Donkin, C.; Brown, S.; Heathcote, A.; Wagenmakers, E.-J.

    2011-01-01

    Quantitative models for response time and accuracy are increasingly used as tools to draw conclusions about psychological processes. Here we investigate the extent to which these substantive conclusions depend on whether researchers use the Ratcliff diffusion model or the Linear Ballistic

  17. Skill-Biased Technological Change in Denmark

    DEFF Research Database (Denmark)

    Malchow-Møller, Nikolaj; Rose Skaksen, Jan

    2003-01-01

    Skill-Biased Technological Change in Denmark:A Disaggregate Perspective@*In this paper, we provide an industry-level analysis of skill-biased technological change(SBTC) in Denmark over the last two decades. The analysis shows that SBTC has variedconsiderably across industries, and traditionally l...... information aboutfuture labour requirements, as the relative importance of these industries must be expectedto grow, thereby reinforcing the shift in demand for skilled labour.JEL Classification: J24, J31, L6Keywords: skill-biased technological change, Danish industries......Skill-Biased Technological Change in Denmark:A Disaggregate Perspective@*In this paper, we provide an industry-level analysis of skill-biased technological change(SBTC) in Denmark over the last two decades. The analysis shows that SBTC has variedconsiderably across industries, and traditionally...... large Danish industries have experiencedrelatively less SBTC. This may partly explain why wage inequality between skilled and lessskilled has risen less in Denmark than in other countries. We also find that SBTC has beenconcentrated in already skill-intensive industries. This contains important...

  18. Velocity bias in a LCDM model

    CERN Document Server

    Colin, Pierre; Kravtsov, A V; Colin, Pedro; Klypin, Anatoly; Kravtsov, Andrey V.

    2000-01-01

    We use N-body simulations to study the velocity bias of dark matter halos, the difference in the velocity fields of dark matter and halos, in a flat low- density LCDM model. The high force, 2kpc/h, and mass, 10^9Msun/h, resolution allows dark matter halos to survive in very dense environments of groups and clusters making it possible to use halos as galaxy tracers. We find that the velocity bias pvb measured as a ratio of pairwise velocities of the halos to that of the dark matter evolves with time and depends on scale. At high redshifts (z ~5) halos move generally faster than the dark matter almost on all scales: pvb(r)~1.2, r>0.5Mpc/h. At later moments the bias decreases and gets below unity on scales less than r=5Mpc/h: pvb(r)~(0.6-0.8) at z=0. We find that the evolution of the pairwise velocity bias follows and probably is defined by the spatial antibias of the dark matter halos at small scales. One-point velocity bias b_v, defined as the ratio of the rms velocities of halos and dark matter, provides a mo...

  19. Graphene nanoribbon devices at high bias

    Science.gov (United States)

    Han, Melinda Y.; Kim, Philip

    2014-02-01

    We present the electron transport in graphene nanoribbons (GNRs) at high electric bias conduction. When graphene is patterned into a few tens of nanometer width of a ribbon shape, the carriers are confined to a quasi-one-dimensional (1D) system. Combining with the disorders in the system, this quantum confinement can lead into a transport gap in the energy spectrum of the GNRs. Similar to CNTs, this gap depends on the width of the GNR. In this review, we examine the electronic properties of lithographically fabricated GNRs, focusing on the high bias transport characteristics of GNRs as a function of density tuned by a gate voltage. We investigate the transport behavior of devices biased up to a few volts, a regime more relevant for electronics applications. We find that the high bias transport behavior in this limit can be described by hot electron scattered by the surface phonon emission, leading to a carrier velocity saturation. We also showed an enhanced current saturation effect in the GNRs with an efficient gate coupling. This effect results from the introduction of the charge neutrality point into the channel, and is similar to pinch-off in MOSFET devices. We also observe that heating effects in graphene at high bias are significant.

  20. Confounding and bias in the attributable fraction.

    Science.gov (United States)

    Darrow, Lyndsey A; Steenland, N Kyle

    2011-01-01

    Inappropriate methods are frequently used to calculate the population attributable fraction (AF) for a given exposure of interest. This commonly occurs when authors use adjusted relative risks (RRs) reported in the literature (the "source" data), without access to the original data. In this analysis, we examine the relationship between the direction and magnitude of confounding in the source data and resulting bias in the attributable fraction when incorrect methods are used. We assess confounding by the confounding risk ratio, which is the ratio of the crude RR to the adjusted RR. We assess bias in the AF by the ratio of the incorrectly calculated AF to the correctly calculated AF. Using generated data, we examine the relationship between confounding and AF bias under various scenarios of population prevalence of exposure and strength of the exposure-disease association. For confounding risk ratios greater than 1.0 (ie, crude RR >adjusted RR), the AF is underestimated; for confounding risk ratios less than 1.0 (ie, crude RR confounding increases, and is dependent on the prevalence of exposure in the total population, with bias greatest at the lowest prevalence of exposure. Bias in the AF is also higher when the exposure-disease association is weaker. Results of these analyses can assist interpretation of incorrectly calculated attributable fraction estimates commonly reported in the epidemiologic literature.

  1. CD bias control on hole pattern

    Science.gov (United States)

    Koike, Kyohei; Hara, Arisa; Natori, Sakurako; Yamauchi, Shohei; Yamato, Masatoshi; Oyama, Kenichi; Yaegashi, Hidetami

    2016-03-01

    Gridded design rules[1] is major process in configuring logic circuit used 193-immersion lithography. In the scaling of grid patterning, we can make 10nm order line and space pattern by using multiple patterning techniques such as self-aligned multiple patterning (SAMP) and litho-etch- litho-etch (LELE)[2][3][5] . On the other hand, Line cut process has some error parameters such as pattern defect, placement error, roughness and X-Y CD bias with the decreasing scale. Especially roughness and X-Y CD bias are paid attention because it cause cut error and pattern defect. In this case, we applied some smoothing process to care hole roughness[4]. Each smoothing process showed different effect on X-Y CD bias. In this paper, we will report the pattern controllability comparison of trench and block + inverse. It include X-Y CD bias, roughness and process usability. Furthermore we will discuss optimum method focused on X-Y CD bias when we use additional process such as smoothing and shrink etching .

  2. Electrostatically biased binding of kinesin to microtubules.

    Directory of Open Access Journals (Sweden)

    Barry J Grant

    2011-11-01

    Full Text Available The minimum motor domain of kinesin-1 is a single head. Recent evidence suggests that such minimal motor domains generate force by a biased binding mechanism, in which they preferentially select binding sites on the microtubule that lie ahead in the progress direction of the motor. A specific molecular mechanism for biased binding has, however, so far been lacking. Here we use atomistic Brownian dynamics simulations combined with experimental mutagenesis to show that incoming kinesin heads undergo electrostatically guided diffusion-to-capture by microtubules, and that this produces directionally biased binding. Kinesin-1 heads are initially rotated by the electrostatic field so that their tubulin-binding sites face inwards, and then steered towards a plus-endwards binding site. In tethered kinesin dimers, this bias is amplified. A 3-residue sequence (RAK in kinesin helix alpha-6 is predicted to be important for electrostatic guidance. Real-world mutagenesis of this sequence powerfully influences kinesin-driven microtubule sliding, with one mutant producing a 5-fold acceleration over wild type. We conclude that electrostatic interactions play an important role in the kinesin stepping mechanism, by biasing the diffusional association of kinesin with microtubules.

  3. Positive outcomes influence the rate and time to publication, but not the impact factor of publications of clinical trial results.

    Directory of Open Access Journals (Sweden)

    Pilar Suñé

    Full Text Available OBJECTIVES: Publication bias may affect the validity of evidence based medical decisions. The aim of this study is to assess whether research outcomes affect the dissemination of clinical trial findings, in terms of rate, time to publication, and impact factor of journal publications. METHODS AND FINDINGS: All drug-evaluating clinical trials submitted to and approved by a general hospital ethics committee between 1997 and 2004 were prospectively followed to analyze their fate and publication. Published articles were identified by searching Pubmed and other electronic databases. Clinical study final reports submitted to the ethics committee, final reports synopses available online and meeting abstracts were also considered as sources of study results. Study outcomes were classified as positive (when statistical significance favoring experimental drug was achieved, negative (when no statistical significance was achieved or it favored control drug and descriptive (for non-controlled studies. Time to publication was defined as time from study closure to publication. A survival analysis was performed using a Cox regression model to analyze time to publication. Journal impact factors of identified publications were recorded. Publication rate was 48·4% (380/785. Study results were identified for 68·9% of all completed clinical trials (541/785. Publication rate was 84·9% (180/212 for studies with results classified as positive and 68·9% (128/186 for studies with results classified as negative (p<0·001. Median time to publication was 2·09 years (IC95 1·61-2·56 for studies with results classified as positive and 3·21 years (IC95 2·69-3·70 for studies with results classified as negative (hazard ratio 1·99 (IC95 1·55-2·55. No differences were found in publication impact factor between positive (median 6·308, interquartile range: 3·141-28·409 and negative result studies (median 8·266, interquartile range: 4·135-17·157. CONCLUSIONS

  4. Is It Still Working? Task Difficulty Promotes a Rapid Wear-Off Bias in Judgments of Pharmacological Products

    OpenAIRE

    Veronika Ilyuk; Lauren Block; David Faro

    2014-01-01

    Misuse of pharmacological products is a major public health concern. Seven studies provide evidence of a rapid wear-off bias in judgments of pharmacological products: consumers infer that duration of product efficacy is dependent on concurrent task difficulty, such that relatively more difficult tasks lead to faster product wear-off. This bias appears to be grounded in consumers' incorrect application of a mental model about substance wear-off based on their experiences with, and beliefs abou...

  5. Treatment with escitalopram improves the attentional bias toward negative facial expressions in patients with major depressive disorders.

    Science.gov (United States)

    Zhou, Zhenhe; Cao, Suxia; Li, Hengfen; Li, Youhui

    2015-10-01

    We hypothesized that treatment with escitalopram would improve cognitive bias and contribute to the recovery process for patients with major depressive disorder (MDD). Many previous studies have established that patients with MDD tend to pay selective attention to negative stimuli. The assessment of the level of cognitive bias is regarded as a crucial dimension of treatment outcomes for MDD. To our knowledge, no prior studies have been reported on the effects of treatment with escitalopram on attentional bias in MDD, employing a dot probe task of facial expression. We studied 25 patients with MDD and 25 controls, and used a dot probe task of facial expression to measure cognitive bias. The patients' psychopathologies were rated using the Hamilton Depression Scale (HAMD) at baseline and after 8 weeks of treatment with escitalopram. All participants performed the facial expression dot probe task. The results revealed that the 8 week escitalopram treatment decreased the HAMD scores. The patients with MDD at baseline exhibited an attentional bias towards negative faces, however, no significant bias toward either negative or happy faces were observed in the controls. After the 8 week escitalopram treatment, no significant bias toward negative faces was observed in the patient group. In conclusion, patients with MDD pay more attention to negative facial expressions, and treatment with escitalopram improves this attentional bias toward negative facial expressions. This is the first study, to our knowledge, on the effects of treatment with escitalopram on attentional bias in patients with MDD that has employed a dot probe task of facial expression.

  6. Public lighting.

    NARCIS (Netherlands)

    2011-01-01

    Visual perception is very important for road users and in the dark it can be facilitated by public lighting. Public lighting has a mostly positive road safety effect. Installing public lighting on roads that were previously unlit generally results in fewer and less serious crashes. This effect seems

  7. Sources and Implications of Bias and Uncertainty in a Century of US Wildfire Activity Data

    Science.gov (United States)

    Short, K.

    2013-12-01

    The statistical analysis of wildfire activity is a critical component of national wildfire planning, operations, and research in the United States (US). Wildfire activity data have been collected in the US for over a century. Yet, to this day, no single unified system of wildfire record-keeping exists. Data for analysis are generally harvested from archival summary reports from federal or interagency fire organizations; incident-level wildfire reporting systems of the federal, state, and local fire services; and, increasingly, remote-sensing programs. It is typical for research into wildfire activity patterns for all or part of the last century to require data from several of these sources and perhaps others. That work is complicated by the disunity of the various datasets and potentially compromised by inherent reporting biases, discussed here. The availability of wildfire records with the information content and geospatial precision generally sought for increasingly popular climatological analyses and the modeling of contemporary wildfire risk is limited to recent decades. We explain how the disunity and idiosyncrasies of US wildfire reporting have largely precluded true interagency, or all-lands, analyses of even recent wildfire activity and hamstrung some early risk modeling efforts. We then describe our efforts to acquire, standardize, error-check, compile, scrub, and evaluate the completeness of US federal, state, and local wildfire records from 1992-2011 for the national interagency Fire Program Analysis (FPA) application. The resulting FPA Fire-Occurrence Database (FPA FOD) includes nearly 1.6 million records from the 20-year period, with values for at least the following core data elements: location at least as precise as a Public Land Survey System section (2.6-km2 grid), discovery date, and final fire size. The FPA FOD is publicly available from the Research Data Archive of the US Department of Agriculture, Forest Service (http://dx.doi.org/10.2737/RDS

  8. Evaluating the statistical conclusion validity of weighted mean results in meta-analysis by analysing funnel graph diagrams.

    Science.gov (United States)

    Elvik, R

    1998-03-01

    The validity of weighted mean results estimated in meta-analysis has been criticized. This paper presents a set of simple statistical and graphical techniques that can be used in meta-analysis to evaluate common points of criticism. The graphical techniques are based on funnel graph diagrams. Problems and techniques for dealing with them that are discussed include: (1) the so-called 'apples and oranges' problem, stating that mean results in meta-analysis tend to gloss over important differences that should be highlighted. A test of the homogeneity of results is described for testing the presence of this problem. If results are highly heterogeneous, a random effects model of meta-analysis is more appropriate than the fixed effects model of analysis. (2) The possible presence of skewness in a sample of results. This can be tested by comparing the mode, median and mean of the results in the sample. (3) The possible presence of more than one mode in a sample of results. This can be tested by forming a frequency distribution of the results and examining the shape of this distribution. (4) The sensitivity of the mean to the possible presence of atypical results (outliers) can be tested by comparing the overall mean to the mean of all results except the one suspected of being atypical. (5) The possible presence of publication bias can be tested by visual inspection of funnel graph diagrams in which data points have been sorted according to statistical significance and direction of effect. (6) The possibility of underestimating the standard error of the mean in meta-analyses by using multiple, correlated results from the same study as the unit of analysis can be addressed by using the jack-knife technique for estimating the uncertainty of the mean. Brief examples, taken from road safety research, are given of all these techniques.

  9. A critical appraisal of epidemiological studies comes from basic knowledge: a reader's guide to assess potential for biases

    Directory of Open Access Journals (Sweden)

    van Duijn Cornelia M

    2007-03-01

    Full Text Available Abstract Scientific literature may be biased because of the internal validity of studies being compromised by different forms of measurement error, and/or because of the selective reporting of positive and 'statistically significant' results. While the first source of bias might be prevented, and in some cases corrected to a degree, the second represents a pervasive problem afflicting the medical literature; a situation that can only be 'corrected' by a change in the mindset of authors, reviewers, and editors. This review focuses on the concepts of confounding, selection bias and information bias, utilising explanatory examples and simple rules to recognise and, when possible, to correct for them. Confounding is a mixing of effects resulting from an imbalance of some of the causes of disease across the compared groups. It can be prevented by randomization and restriction, and controlled by stratification, standardization or by using multivariable techniques. Selection bias stems from an absence of comparability among the groups being studied, while information bias arises from distorted information collection techniques. Publication bias of medical research results can invalidate evidence-based medicine, when a researcher attempting to collect all the published studies on a specific topic actually gathers only a proportion of them, usually the ones reporting 'positive' results. The selective publication of 'statistically significant' results represents a problem that researchers and readers have to be aware of in order to face the entire body of published medical evidence with a degree of scepticism.

  10. A critical appraisal of epidemiological studies comes from basic knowledge: a reader's guide to assess potential for biases

    Science.gov (United States)

    Boccia, Stefania; La Torre, Giuseppe; Persiani, Roberto; D'Ugo, Domenico; van Duijn, Cornelia M; Ricciardi, Gualtiero

    2007-01-01

    Scientific literature may be biased because of the internal validity of studies being compromised by different forms of measurement error, and/or because of the selective reporting of positive and 'statistically significant' results. While the first source of bias might be prevented, and in some cases corrected to a degree, the second represents a pervasive problem afflicting the medical literature; a situation that can only be 'corrected' by a change in the mindset of authors, reviewers, and editors. This review focuses on the concepts of confounding, selection bias and information bias, utilising explanatory examples and simple rules to recognise and, when possible, to correct for them. Confounding is a mixing of effects resulting from an imbalance of some of the causes of disease across the compared groups. It can be prevented by randomization and restriction, and controlled by stratification, standardization or by using multivariable techniques. Selection bias stems from an absence of comparability among the groups being studied, while information bias arises from distorted information collection techniques. Publication bias of medical research results can invalidate evidence-based medicine, when a researcher attempting to collect all the published studies on a specific topic actually gathers only a proportion of them, usually the ones reporting 'positive' results. The selective publication of 'statistically significant' results represents a problem that researchers and readers have to be aware of in order to face the entire body of published medical evidence with a degree of scepticism. PMID:17359550

  11. Clinical trial registration was not an indicator for low risk of bias.

    Science.gov (United States)

    Farquhar, Cynthia M; Showell, Marian G; Showell, Emily A E; Beetham, Penny; Baak, Nora; Mourad, Selma; Jordan, Vanessa M B

    2017-04-01

    To determine the prevalence of registered trials and to evaluate the risk of bias between registered and unregistered clinical trials. The Cochrane Gynecology and Fertility Group's specialized register was searched on November 5, 2015, for randomized controlled trials published from 2010 to 2014. Studies were selected if they had randomized women or men for fertility treatments, were published in full text and written in English. Two reviewers then independently assessed trial registration status for each trial, by searching the publication, trial registries, and by contacting the original authors. Of 693 eligible randomized controlled trials, only 44% were found to be registered. Unregistered clinical trials had smaller sample sizes than registered trials (P risk of bias using five of the Cochrane Risk of Bias "domains." Registered and unregistered trials differed in their risk of bias for random sequence generation (P = 0.001), allocation concealment (P = 0.003), and selective reporting (P  0.05) domains. Only 54 (43.2%) of the 125 registered trials were registered prospectively. This study has the following limitations. Only English language trials were included in this review. We were unable to obtain protocols for the unregistered trials and therefore were unable to assess the risk of bias in the selective reporting domain. All available trials should be included in systematic reviews and assessed for risk of bias as there are both registered trials with high risk of bias and unregistered trials with low risk of bias and by excluding unregistered trials more than half of the available evidence will be lost. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. A Comparison of attentional biases and memory biases in social phobia and major depression

    NARCIS (Netherlands)

    Rinck, M.; Becker, E.S.

    2005-01-01

    Cognitive processes play an important role in the etiology and maintenance of anxiety and depression. Current theories differ, however, in their predictions regarding the occurrence of attentional biases and memory biases in depression and anxiety. To allow for a systematic comparison of disorders a

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

    DEFF Research Database (Denmark)

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

    2011-01-01

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

  14. Expectancy biases in fear and anxiety and their link to biases in attention.

    Science.gov (United States)

    Aue, Tatjana; Okon-Singer, Hadas

    2015-12-01

    Healthy individuals often exhibit prioritized processing of aversive information, as manifested in enhanced orientation of attention to threatening stimuli compared with neutral items. In contrast to this adaptive behavior, anxious, fearful, and phobic individuals show exaggerated attention biases to threat. In addition, they overestimate the likelihood of encountering their feared stimulus and the severity of the consequences; both are examples of expectancy biases. The co-occurrence of attention and expectancy biases in fear and anxiety raises the question about causal influences. Herein, we summarize findings related to expectancy biases in fear and anxiety, and their association with attention biases. We suggest that evidence calls for more comprehensive research strategies in the investigation of mutual influences between expectancy and attention biases, as well as their combined effects on fear and anxiety. Moreover, both types of bias need to be related to other types of distorted information processing commonly observed in fear and anxiety (e.g., memory and interpretation biases). Finally, we propose new research directions that may be worth considering in developing more effective treatments for anxiety disorders.

  15. Piezoelectric tuning of exchange bias from negative to positive bias fields

    Science.gov (United States)

    Polisetty, Srinivas; Binek, Christian; Sahoo, Sarbeswar

    2010-03-01

    Tuning of the exchange bias has been attempted using magnetoelectric and multiferroic systems. Alternatively, we propose tuning of the exchange bias via the piezoelectric property of ferroelectric material. A ferromagnetic Co thin film is deposited on top of a ferroelectric tetragonal BaTiO3 (001) by using MBE at a base pressure of 1.5x10^10 m bar. An ex-situ antiferromagnetic CoO film is naturally formed on top of the Co Hereby, the piezoelectric BaTiO3 induced electrically tunable stress in the adjacent Co film. The stress induced strain alters the magnetic anisotropy of the Co film and by that the magnetization at the Co/CoO-interface modifying the exchange bias field. This includes sign change of the exchange bias from negative to positive bias fields by increasing electric field applied on BaTiO3. The observed complex electric field dependence of the exchange bias is interpreted through competition between ferromagnetic and antiferromagnetic exchange at the rough Co/CoO interface. The competition involves weakening of negative exchange bias through deviations from collineraity of the Co and CoO interface magnetization and simultaneous activation of antiferromagnetic exchange giving rise to a crossover into positive exchange bias.

  16. Cognitive Bias Modification Training in Adolescents: Effects on Interpretation Biases and Mood

    Science.gov (United States)

    Lothmann, Claudia; Holmes, Emily A.; Chan, Stella W. Y.; Lau, Jennifer Y. F.

    2011-01-01

    Background: Negative biases in the interpretation of ambiguous material have been linked to anxiety and mood problems. Accumulating data from adults show that positive and negative interpretation styles can be induced through cognitive bias modification (CBM) paradigms with accompanying changes in mood. Despite the therapeutic potential of…

  17. Thinking in Black and White: Conscious thought increases racially biased judgments through biased face memory

    NARCIS (Netherlands)

    Strick, M.A.; Stoeckart, P.F.; Dijksterhuis, A.J.

    2015-01-01

    It is a common research finding that conscious thought helps people to avoid racial discrimination. These three experiments, however, illustrate that conscious thought may increase biased face memory, which leads to increased judgment bias (i.e., preferring White to Black individuals). In Experiment

  18. Optimism Bias in Fans and Sports Reporters.

    Directory of Open Access Journals (Sweden)

    Bradley C Love

    Full Text Available People are optimistic about their prospects relative to others. However, existing studies can be difficult to interpret because outcomes are not zero-sum. For example, one person avoiding cancer does not necessitate that another person develops cancer. Ideally, optimism bias would be evaluated within a closed formal system to establish with certainty the extent of the bias and the associated environmental factors, such that optimism bias is demonstrated when a population is internally inconsistent. Accordingly, we asked NFL fans to predict how many games teams they liked and disliked would win in the 2015 season. Fans, like ESPN reporters assigned to cover a team, were overly optimistic about their team's prospects. The opposite pattern was found for teams that fans disliked. Optimism may flourish because year-to-year team results are marked by auto-correlation and regression to the group mean (i.e., good teams stay good, but bad teams improve.

  19. Motion, identity and the bias toward agency

    Directory of Open Access Journals (Sweden)

    Chris eFields

    2014-08-01

    Full Text Available The well-documented human bias toward agency as a cause and therefore an explanation of observed events is typically attributed to evolutionary selection for a social brain. Based on a review of developmental and adult behavioral and neurocognitive data, it is argued that the bias toward agency is a result of the default human solution, developed during infancy, to the computational requirements of object re-identification over gaps in observation of more than a few seconds. If this model is correct, overriding the bias toward agency to construct mechanistic explanations of observed events requires structure-mapping inferences, implemented by the pre-motor action planning system, that replace agents with mechanisms as causes of unobserved changes in contextual or featural properties of objects. Experiments that would test this model are discussed.

  20. Recursive bias estimation for high dimensional smoothers

    Energy Technology Data Exchange (ETDEWEB)

    Hengartner, Nicolas W [Los Alamos National Laboratory; Matzner-lober, Eric [UHB, FRANCE; Cornillon, Pierre - Andre [INRA

    2008-01-01

    In multivariate nonparametric analysis, sparseness of the covariates also called curse of dimensionality, forces one to use large smoothing parameters. This leads to biased smoothers. Instead of focusing on optimally selecting the smoothing parameter, we fix it to some reasonably large value to ensure an over-smoothing of the data. The resulting smoother has a small variance but a substantial bias. In this paper, we propose to iteratively correct the bias initial estimator by an estimate of the latter obtained by smoothing the residuals. We examine in detail the convergence of the iterated procedure for classical smoothers and relate our procedure to L{sub 2}-Boosting. We apply our method to simulated and real data and show that our method compares favorably with existing procedures.