Bayesian benefits with JASP

We illustrate the Bayesian approach to data analysis using the newly developed statistical software program JASP. With JASP, researchers are able to take advantage of the benefits that the Bayesian framework has to offer in terms of parameter estimation and hypothesis testing. The Bayesian advantages are discussed using real data on the relation between Quality of Life and Executive Functioning in children with Autism Spectrum Disorder.     

决策信心的认知机制与神经基础

决策信心是指在进行判断或决策时, 个体对其决策最优性或正确性的信心程度。决策信心的单过程理论认为决策与信心评估是并行的同一加工过程; 而决策后理论认为决策和信心评估是串行的两个加工过程。决策信心存在两种典型的偏差效应：过分自信和信心不足。决策信心的神经机制研究指出, 信心评估可能是决策过程中最基本并且普遍存在的一个成分; 对决策信心评估敏感的脑区包括扣带回、背外侧前额叶和顶上小叶等。未来研究应该在决策信心产生的机制、信心与决策如何交互的心理及神经机制等领域展开大量研究。     

More than,less than,or minimum,maximum: how upper and lower bounds determine subjective interval estimates

Uncertain quantities can be described by single‐point estimates of lower interval bounds (X₁), upper interval bounds (X₂), two‐bound estimates (separate estimates of X₁ and X₂), and by ranges (X₁?X₂). A price estimation task showed that single‐bound estimates phrased as “T costs more than X₁” and “T costs less than X₂,” yielded much larger intervals than “minimum X₁” and “maximum X₂.” This difference can be attributed to exclusive interpretations of X₁ and X₂ in the first case (X₁ and X₂ are unlikely values), and inclusive interpretations in the second (X₁ and X₂ are likely values). This pattern of results was replicated in other domains where participants estimated single targets. When they estimated a distribution of targets, the pattern was reversed. “Minimum” and “maximum” values of variable quantities (e.g., flight prices) were found to delimit larger intervals than “more than” and “less than” estimates. Copyright © 2006 John Wiley & Sons, Ltd.     

Deteriorating memory confidence, responsibility perceptions and repeated checking: comparisons in OCD and control samples

Repeated checking has been repeatedly associated with memory distrust. We sought to extend previous research using a computer-based checking task by incorporating a group of 15 individuals with OCD, and examining the effect of increased perceived responsibility. Participants were asked to repeatedly check a virtual stovetop, with half the participants also placed under a condition of high-perceived responsibility. Our observations replicated previous research showing that the act of repeatedly checking leads to reductions in memory vividness, detail and confidence, without accompanying reductions in memory accuracy. Furthermore, while a sense of increased personal responsibility had little effect on a student control sample, it led to a significant further deterioration in memory confidence in individuals with OCD. These results suggest that in people with OCD, normal reductions in memory confidence over repeated trials are exacerbated and intensified by inflated responsibility perceptions.     

Inferring accuracy for judges and items: Choice of unit of analysis reverses the conclusions

This study explores the relationship between the precision and the accuracy of forecasts using either judge or item as the unit of analysis. Participants in five experiments answered general-knowledge questions by indicating intervals that were likely to include the correct answer. Results indicate that the precision of an interval estimate is not a straightforward cue to the likelihood that such an interval includes the truth (hit rate). Whereas judges who state more precise estimates (i.e. who provide narrower interval estimates) have lower hit rates, questions for which the average judgment is more precise have higher hit rates. Thus, the relation between precision and accuracy depends on whether one ‘slices’ the data by judge or by question. We offer an explanation for this seemingly paradoxical effect and implement it as a computer simulation to demonstrate its validity. © 1997 John Wiley & Sons, Ltd.     

Precision and accuracy of judgmental estimation

Whereas probabilistic calibration has been a central normative concept of accuracy in previous research on interval estimates, we suggest here that normative approaches for the evaluation of judgmental estimates should consider the communicative interaction between the individuals who produce the judgments and those who receive or use them for making decisions. We analyze precision and error in judgment and consider the role of the accuracy–informativeness trade-off (Yaniv and Foster, 1995) in the communication of estimates. The results shed light on puzzling findings reported earlier in the literature concerning the calibration of subjective confidence intervals. © 1997 John Wiley & Sons, Ltd.     

Knowing who knows: Metacognitive and causal learning abilities guide infants’ selective social learning

Given the widespread interest in the development of children's selective social learning, there is mounting evidence suggesting that infants prefer to learn from competent informants (Poulin‐Dubois & Brosseau‐Liard, Current Directions in Psychological Science, 2016, 25). However, little research has been dedicated to understanding how this selectivity develops. The present study investigated whether causal learning and precursor metacognitive abilities govern discriminant learning in a classic word‐learning paradigm. Infants were exposed to a speaker who accurately (reliable condition) or inaccurately (unreliable condition) labeled familiar objects and were subsequently tested on their ability to learn a novel word from the informant. The predictive power of causal learning skills and precursor metacognition (as measured through decision confidence) on infants' word learning was examined across both reliable and unreliable conditions. Results suggest that infants are more inclined to accept an unreliable speaker's testimony on a word learning task when they also lack confidence in their own knowledge on a task measuring their metacognitive ability. Additionally, when uncertain, infants draw on causal learning abilities to better learn the association between a label and a novel toy. This study is the first to shed light on the role of causal learning and precursor metacognitive judgments in infants' abilities to engage in selective trust.     

Point-biserial correlation: Interval estimation,hypothesis testing,meta-analysis,and sample size determination

The point-biserial correlation is a commonly used measure of effect size in two-group designs. New estimators of point-biserial correlation are derived from different forms of a standardized mean difference. Point-biserial correlations are defined for designs with either fixed or random group sample sizes and can accommodate unequal variances. Confidence intervals and standard errors for the point-biserial correlation estimators are derived from the sampling distributions for pooled-variance and separate-variance versions of a standardized mean difference. The proposed point-biserial confidence intervals can be used to conduct directional two-sided tests, equivalence tests, directional non-equivalence tests, and non-inferiority tests. A confidence interval for an average point-biserial correlation in meta-analysis applications performs substantially better than the currently used methods. Sample size formulas for estimating a point-biserial correlation with desired precision and testing a point-biserial correlation with desired power are proposed. R functions are provided that can be used to compute the proposed confidence intervals and sample size formulas.     

Initial judgment task and delay of the final validity-rating task moderate the truth effect

Repeatedly seen or heard statements are typically judged to be more valid than statements one has never encountered before. This phenomenon has been referred to as the truth effect. We conducted two experiments to assess the plasticity of the truth effect under different contextual conditions. Surprisingly, we did not find a truth effect in the typical judgment design when using a ten minutes interval between statement repetitions. However, we replicated the truth effect when changing the judgment task at initial statement exposure or when using an interval of one week rather than ten minutes. Because none of the current truth effect theories can fully account for these context effects, we conclude that the cognitive processes underlying truth judgments are more complex than has hitherto been assumed. To close the theoretical gap, we propose a revised fluency attribution hypothesis as a possible explanation of our findings.     

Collective decision making reduces metacognitive control and increases error rates,particularly for overconfident individuals

This research aimed to investigate the changes in judgment accuracy, confidence, control thresholds, and decision outcomes when people act in two-person groups (dyads) compared with acting individually. First, we used interacting dyads to determine the metacognitive and behavioral outcomes of collective decision making and compared them with those of individuals. Second, we examined whether these changes were related to the trait-confidence and bias of individuals working together. Using a within-person design, undergraduate psychology students (N = 116) completed a General-knowledge Test individually, then together as a dyad. Each question was accompanied by a confidence rating and a decision to bet $10 on the answer. Dyads had significantly higher confidence and lower control thresholds than individuals. They were also significantly more decisive (made more bets) and reckless (lost a higher rate of bets) than when working alone. Thus, we observed a higher rate of decision errors for groups than individuals. The results also demonstrated the important role of individual differences: Overconfident individuals became even more confident, decisive, and reckless when working together compared with less confident or underconfident individuals working together. These findings have important theoretical and applied implications for collective decision making; metacognitive bias and potentially control thresholds may be targeted to alleviate the larger error rates and guide the formation of more effective groups.