When Extremists Win: Cultural Transmission Via Iterated Learning When Populations Are Heterogeneous

How does the process of information transmission affect the cultural or linguistic products that emerge? This question is often studied experimentally and computationally via iterated learning, a procedure in which participants learn from previous participants in a chain. Iterated learning is a powerful tool because, when all participants share the same priors, the stationary distributions of the iterated learning chains reveal those priors. In many situations, however, it is unreasonable to assume that all participants share the same prior beliefs. We present four simulation studies and one experiment demonstrating that when the population of learners is heterogeneous, the behavior of an iterated learning chain can be unpredictable and is often systematically distorted by the learners with the most extreme biases. This results in group‐level outcomes that reflect neither the behavior of any individuals within the population nor the overall population average. We discuss implications for the use of iterated learning as a methodological tool as well as for the processes that might have shaped cultural and linguistic evolution in the real world.     

Biases and Heuristics in Decision Making and Their Impact on Autonomy

Cognitive scientists have identified a wide range of biases and heuristics in human decision making over the past few decades. Only recently have bioethicists begun to think seriously about the implications of these findings for topics such as agency, autonomy, and consent. This article aims to provide an overview of biases and heuristics that have been identified and a framework in which to think comprehensively about the impact of them on the exercise of autonomous decision making. I analyze the impact that these biases and heuristics have on the following dimensions of autonomy: understanding, intentionality, absence of alienating or controlling influence, and match between formally autonomous preferences or decisions and actual choices or actions.     

The illusion of knowledge: When more information reduces accuracy and increases confidence

Intuition suggests that having more information can increase prediction accuracy of uncertain outcomes. In four experiments, we show that more knowledge can decrease accuracy and simultaneously increase prediction confidence. Participants were asked to predict basketball games sampled from a National Basketball Association season. All participants were provided with statistics (win record, halftime score), while half were additionally given the team names. Knowledge of names increased the confidence of basketball fans consistent with their belief that this knowledge improved their predictions. Contrary to this belief, it decreased the participants’ accuracy by reducing their reliance on statistical cues. One of the factors contributing to this underweighting of statistical cues was a bias to bet on more familiar teams against the statistical odds. Finally, in a real betting experiment, fans earned less money if they knew the team names while persisting in their belief that this knowledge improved their predictions.     

Do aggression and rule‐breaking have different interpersonal correlates? A study of antisocial behavior subtypes,negative affect,and hostile perceptions of others

There is mounting evidence that physical aggression and nonaggressive, rule‐breaking delinquency constitute two separable though correlated subtypes of antisocial behavior. Even so, it remains unclear whether these behavioral subtypes have meaningfully different interpersonal correlates, particularly as they are subsumed within the same broad domain of antisocial behavior. To evaluate this, we examined whether hostile perceptions of others (assessed via exposure to a series of neutral unknown faces) were linked to level and type of antisocial behavior aggression vs. rule‐breaking, and moreover, whether this association persisted even when also considering the common association with negative affect (as manipulated via written recollection of one's best and worst life experiences). Analyses revealed that aggression, but not rule‐breaking, was uniquely tied to hostile perceptions of others. Furthermore, this association persisted over and above the common association of both hostile perceptions and aggression with negative affect (at both trait and state levels). Such results provide additional support for clinically meaningful differences between the behavioral subtypes of aggression and nonaggressive rule‐breaking and for the independent role of hostile perceptions in aggressive behavior. Aggr. Behav. 35:453–461, 2009. © 2009 Wiley‐Liss, Inc.     

Better in the (near) future: Group-based differences in forecasting biases

Social identities are an important component of an individual’s self-concept. In the current research, we examine how identification with a group can lead to biased intergroup judgments similar to those made when evaluating the self, relative to others. We compared evaluations of in- and outgroups in order to examine differences in temporal perspective and optimistic evaluations. Our findings suggest that compared to an outgroup, ingroup members more strongly consider the future potential of their group, are more optimistic when considering future ingroup outcomes, and hold a more uniformly positive view of an ingroup’s future. Furthermore, we find that when evaluating ingroups, shifts in temporal perspectives are related to greater optimism. We conclude by discussing theoretical implications and future research related to temporal judgments and social groups.     

Why should we try to think like scientists? Scientific reasoning and susceptibility to epistemically suspect beliefs and cognitive biases

This paper examines whether scientific reasoning skills predict people's susceptibility to epistemically suspect beliefs and cognitive biases. We used the recently developed Scientific Reasoning Scale (SRS) because it measures the ability to read and evaluate scientific evidence. Alongside the SRS, 317 participants aged 18–30 years completed measures of thinking dispositions and cognitive ability to ascertain whether the SRS contributes specifically to susceptibility to epistemically suspect beliefs and cognitive biases. Scientific reasoning correlated positively with dispositions towards analytic thinking and cognitive ability and negatively with dogmatism, epistemically suspect beliefs, and susceptibility to cognitive biases. Most importantly, it emerged as a significant predictor, contributing to susceptibility to both cognitive biases and epistemically suspect beliefs over and above the other cognitive predictors. These results provide the first empirical evidence that scientific reasoning ability is an important factor in protecting against epistemically suspect beliefs and in aiding better decision making among the non-scientific population.     

Interpreting Silent Gesture: Cognitive Biases and Rational Inference in Emerging Language Systems

Natural languages make prolific use of conventional constituent‐ordering patterns to indicate “who did what to whom,” yet the mechanisms through which these regularities arise are not well understood. A series of recent experiments demonstrates that, when prompted to express meanings through silent gesture, people bypass native language conventions, revealing apparent biases underpinning word order usage, based on the semantic properties of the information to be conveyed. We extend the scope of these studies by focusing, experimentally and computationally, on the interpretation of silent gesture. We show cross‐linguistic experimental evidence that people use variability in constituent order as a cue to obtain different interpretations. To illuminate the computational principles that govern interpretation of non‐conventional communication, we derive a Bayesian model of interpretation via biased inductive inference and estimate these biases from the experimental data. Our analyses suggest people's interpretations balance the ambiguity that is characteristic of emerging language systems, with ordering preferences that are skewed and asymmetric, but defeasible.     

Examining Autobiographical Memory Content in Patients with Depression and Anxiety Disorders

The purpose of this study was to move beyond the traditional specificity model of autobiographical memory (ABM) and to examine the content of memories with a focus on disorder and schema-relevant content. The sample (N = 82) included 25 patients with major depressive disorder (MDD), 24 with social phobia (SP), and 33 with panic disorder with agoraphobia (PDA) who were referred to a large outpatient clinic for group treatment of depression or anxiety. Participants completed the Autobiographical Memory Test (AMT) and Beck Depression Inventory–II as part of the clinical intake process. Responses to the AMT were coded for disorder-specific content based on diagnostic criteria for each disorder as well as for schema-relevant (sociotropy vs. autonomy) content. A repeated measures multiple analysis of variance demonstrated significant differences in disorder-specific content, with patients in the MDD group reporting more depressotypic ABMs than those in the PDA group but not the SP group. Similarly, in the analysis of schema-relevant content, significant differences were found between MDD and PDA regarding the presence of autonomy-based ABM ratings. Study results provide partial support for the cognitive specificity hypothesis with ABM content. The results are discussed in relation to the cognitive models of depression and anxiety.     

Causal Inference from Descriptions of Experimental and Non-Experimental Research: Public Understanding of Correlation-Versus-Causation

The human tendency to conflate correlation with causation has been lamented by various scientists (Kida, 2006; Stanovich, 2009), and vivid examples of it can be found in both the media and peer-reviewed literature. However, there is little systematic data on the extent to which individuals conflate correlation with causation. In three experiments, we presented people with one of four research vignettes generated from the combination of two independent variables: whether the vignette described an experimental or non-experimental design, and whether it revealed a positive or negative association. Upon reading their vignette, participants selected inferences that could be drawn from the findings. Participants drew causal inferences from non-experimental vignettes as often as they did from experimental vignettes, and more frequently for causal statements and directions of association that fit with intuitive notions than for those that did not. We discuss our findings in relation to other biases in human thinking.     

Cognitive processes as mediators of the relation between mindfulness and change in social anxiety symptoms following cognitive behavioral treatment

The present study examined whether pretreatment mindfulness exerts an indirect effect on outcomes following cognitive-behavioral therapy (CBT). Cognitive processes of probability and cost bias (i.e., overestimations of the likelihood that negative social events will occur, and that these events will have negative consequences when they do occur) were explored as potential mediators of the relation between mindfulness and social anxiety symptom change. People with higher levels of mindfulness may be better able to benefit from treatments that reduce biases because mindfulness may aid in regulation of attention. Sixty-seven individuals with a primary diagnosis of social phobia identifying public speaking as their greatest fear received eight sessions of one of two types of exposure-based CBT delivered according to treatment manuals. Participants completed self-report measures of mindfulness, probability bias, cost bias, and social anxiety symptoms. Mediation hypotheses were assessed by a bootstrapped regression using treatment outcome data. Pretreatment mindfulness was not related to change in social anxiety symptoms from pre- to posttreatment. However, mindfulness had an indirect effect on treatment outcome via its association with probability bias, but not cost bias, at midtreatment. These findings were consistent across three metrics of social anxiety symptoms. Mindfulness may play a role in response to CBT among individuals with social phobia through its relation with probability bias – even when the treatment does not target mindfulness.