The Equiprobability Bias from a Mathematical and Psychological Perspective

The equiprobability bias (EB) is a tendency to believe that every process in which randomness is involved corresponds to a fair distribution, with equal probabilities for any possible outcome. The EB is known to affect both children and adults, and to increase with probability education. Because it results in probability errors resistant to pedagogical interventions, it has been described as a deep misconception about randomness: the erroneous belief that randomness implies uniformity. In the present paper, we show that the EB is actually not the result of a conceptual error about the definition of randomness. On the contrary, the mathematical theory of randomness does imply uniformity. However, the EB is still a bias, because people tend to assume uniformity even in the case of events that are not random. The pervasiveness of the EB reveals a paradox: The combination of random processes is not necessarily random. The link between the EB and this paradox is discussed, and suggestions are made regarding educational design to overcome difficulties encountered by students as a consequence of the EB.     

The Appeal to Expert Opinion: Quantitative Support for a Bayesian Network Approach

The appeal to expert opinion is an argument form that uses the verdict of an expert to support a position or hypothesis. A previous scheme‐based treatment of the argument form is formalized within a Bayesian network that is able to capture the critical aspects of the argument form, including the central considerations of the expert's expertise and trustworthiness. We propose this as an appropriate normative framework for the argument form, enabling the development and testing of quantitative predictions as to how people evaluate this argument, suggesting that such an approach might be beneficial to argumentation research generally. We subsequently present two experiments as an example of the potential for future research in this vein, demonstrating that participants' quantitative ratings of the convincingness of a proposition that has been supported with an appeal to expert opinion were broadly consistent with the predictions of the Bayesian model.     

Ease‐of‐retrieval effects on procedural justice judgements under conditions of informational and personal uncertainty

This study tests whether individuals' reliance on ease‐of‐retrieval processes when forming procedural justice judgements are moderated by informational and personal uncertainty. In Studies 1 and 2 we examined the predicted effects of informational uncertainty. Results indicated that participants in information‐uncertain conditions relied on ease‐of‐retrieval, whereas those in information‐certain conditions relied on content information to make procedural justice judgements. In Study 3 we examined the combined effects of informational uncertainty and personal uncertainty on reliance on ease‐of‐retrieval when forming procedural justice judgements. The findings of Study 3 indicated that personal uncertain participants who were in informational certain conditions based their procedural justice judgements on content information, whereas all other participants based their procedural justice judgements on ease‐of‐retrieval. This is the first paper to demonstrate that the joint effect of informational uncertainty and personal uncertainty on reliance on ease‐of‐retrieval is different from the two uncertainties acting alone.     

非参数认知诊断方法下诊断结果的概率化表征

非参数认知诊断分类方法非常适合课堂评估,其诊断结果采用0-1形式而缺乏概率化表征,不能精细地区分被试属性掌握程度的差异或变化,还缺乏可用于评价真实测验分类结果的信度和效度指标。要刻画被试属性掌握程度的差异,首要的问题是要为非参数认知诊断方法提供一种可以量化属性掌握概率的方法。针对此问题,基于二项分布和玻尔兹曼分布提出非参数认知诊断方法下诊断结果的概率化表征方法,并用于构建分类准确性和分类一致性指标。模拟研究与实测数据分析结果显示：概率化表征方法与非参数认知诊断方法的分类结果高度一致;概率化表征方法与认知诊断模型所得的属性掌握概率十分接近;概率化表征方法所得的属性（模式）掌握概率可用于计算属性（模式）分类准确性和分类一致性指标,在实际测验情景下可作为信度和效度指标,评价诊断结果的重测一致率和判准率。     

认知灵活性对概率类别学习的影响

本研究采用“数字-字母转换任务”区分高低认知灵活性者, 构建概率配对模式相同但形式不同的两个概率类别学习任务, 借助ERP技术探讨认知灵活性对概率类别学习任务的作用特点与机制。结果发现, 本研究的两个任务中, 高认知灵活性组的规则习得水平均优于低认知灵活性组, 认知灵活性能促进概率类别的学习。同时, 对不同学习阶段的ERPs分析结果显示, 高认知灵活性者在概率类别学习中的优势源于反馈加工过程。     

How Affect Shapes Risky Choice: Distorted Probability Weighting Versus Probability Neglect

People's choices between prospects with relatively affect‐rich outcomes (e.g., medical side effects) can diverge markedly from their choices between prospects with relatively affect‐poor outcomes (e.g., monetary losses). We investigate the cognitive mechanisms underlying this “affect gap” in risky choice. One possibility is that affect‐rich prospects give rise to more distortion in probability weighting. Another is that they lead to the neglect of probabilities. To pit these two possibilities against each other, we fitted cumulative prospect theory (CPT) to the choices of individual participants, separately for choices between options with affect‐rich outcomes (adverse medical side effects) and options with affect‐poor outcomes (monetary losses); additionally, we tested a simple model of probability neglect, the minimax rule. The results indicated a qualitative difference in cognitive mechanisms between the affect‐rich and affect‐poor problems. Specifically, in affect‐poor problems, the large majority of participants were best described by CPT; in affect‐rich problems, the proportion of participants best described by the minimax rule was substantially higher. The affect gap persisted even when affect‐rich outcomes were supplemented by numerical information, thus providing no support for the thesis that choices in affect‐rich and affect‐poor problems diverge because the information provided in the former is nonnumerical. Our findings suggest that the traditional expectation‐based framework for modeling risky decision making may not readily generalize to affect‐rich choices. Copyright © 2015 John Wiley & Sons, Ltd.     

A contextual approach on sex-related biases in pain judgements: The moderator effects of evidence of pathology and patients’ distress cues on nurses’ judgements of chronic low-back pain

Although women report feeling more pain than men, their pain is often underdiagnosed and undertreated. By proposing a gender-based theoretical conceptualisation, we argue that such sex-related biases may be enhanced or suppressed by contextual variables pertaining to the clinical situation, the perceiver or the patient. Consequently, we aimed to explore the moderator role of two clinically relevant variables in a chronic low-back pain (CLBP) scenario: diagnostic evidence of pathology (EP) and pain behaviours conveying distress. One-hundred and twenty-six female nurses (M?=?35.33, SD?=?7.64) participated in an experimental between-subjects design, 2 (patient's sex)?×?2 (EP: present vs. absent)?×?2 (pain behaviours: with vs. without distress). Independent variables were operationalised by vignettes depicting a patient with CLBP. Nurses judged the patient's pain on several dimensions: (1) credibility; (2) disability; (3) severity of the clinical situation; (4) psychological attributions and (5) willingness to offer support. Main findings showed that judgements of women's pain were influenced by EP, while judgements of men's pain were not. Moreover, nurses showed biases against men, but only in the presence of EP. The influence of distress cues was less consistent. Theoretical and practical implications are drawn.