Contingency learning and stereotype formation: Illusory and spurious correlations revisited

The Origin of Illusory Correlations

If the distributions of two binary variables are skewed, people erroneously perceive a correlation even if the variables are actually uncorrelated. Specifically, people perceive a correlation between the variables' infrequent (vs. frequent) levels. While such systematic Illusory Correlations (ICs) can account for important phenomena, including erroneous stereotypes linking minority groups with infrequent attributes, the theoretical explanation is still a matter of debate. As proposed in the distinctiveness-based account, ICs arise due to a memory advantage for infrequent events. Alternatively, it has been proposed that ICs reflect ad hoc inferences from univariate base rates. In two experiments, we tested the accounts' predictions using a standard IC paradigm followed by (1) a contingency judgment task, asking participants to directly report contingencies, and (2) a trial-by-trial source assignment task of group membership and attribute. Bayesian-hierarchical model analysis revealed that ICs in contingency judgments were positively correlated to ad hoc inferences, but uncorrelated to exemplar memory in participants' source assignments. Moreover, inducing a focus on infrequent events improved memory for distinct events, but did not result in stronger ICs. Thus, our results support the explanation of ICs as ad hoc inferences from base rates, rather than a memory advantage for distinctive item combinations.

'I feel better when…': An analysis of the memory-experience gap for peoples' estimates of the relationship between health behaviours and experiences

OBJECTIVE

People often overestimate how strongly behaviours and experiences are related. This memory-experience gap might have important implications for health care settings, which often require people to estimate associations, such as "my mood is better when I exercise". This study examines how subjective correlation estimates between health behaviours and experiences relate to calculated correlations from online reports and whether subjective estimates are associated with engagement in actual health behaviour.

DESIGN

Seven-month online study on physical activity, sleep, affect and stress, with 61 online assessments.

MAIN OUTCOME MEASURES

University students (N = 168) retrospectively estimated correlations between physical activity, sleep, positive affect and stress over the seven-month study period.

RESULTS

Correlations between experiences and behaviours (online data) were small (r = -.12-.14), estimated correlations moderate (r = -.35-.24). Correspondence between calculated and estimated correlations was low. Importantly, estimated correlations of physical activity with stress, positive affect and sleep were associated with actual engagement in physical activity.

CONCLUSION

Estimation accuracy of relations between health behaviours and experiences is low. However, association estimates could be an important predictor of actual health behaviours. This study identifies and quantifies estimation inaccuracies in health behaviours and points towards potential systematic biases in health settings, which might seriously impair intervention efficacy.

Statistical numeracy as a moderator of (pseudo)contingency effects on decision behavior

Pseudocontingencies denote contingency estimates inferred from base rates rather than from cell frequencies. We examined the role of statistical numeracy for effects of such fallible but adaptive inferences on choice behavior. In Experiment 1, we provided information on single observations as well as on base rates and tracked participants' eye movements. In Experiment 2, we manipulated the availability of information on cell frequencies and base rates between conditions. Our results demonstrate that a focus on base rates rather than cell frequencies benefits pseudocontingency effects. Learners who are more proficient in (conditional) probability calculation prefer to rely on cell frequencies in order to judge contingencies, though, as was evident from their gaze behavior. If cell frequencies are available in summarized format, they may infer the true contingency between options and outcomes. Otherwise, however, even highly numerate learners are susceptible to pseudocontingency effects.

Analyzing Stochastic Dependence of Cognitive Processes in Multidimensional Source Recognition

Stochastic dependence among cognitive processes can be modeled in different ways, and the family of multinomial processing tree models provides a flexible framework for analyzing stochastic dependence among discrete cognitive states. This article presents a multinomial model of multidimensional source recognition that specifies stochastic dependence by a parameter for the joint retrieval of multiple source attributes together with parameters for stochastically independent retrieval. The new model is equivalent to a previous multinomial model of multidimensional source memory for a subset of the parameter space. An empirical application illustrates the advantages of the new multinomial model of joint source recognition. The new model allows for a direct comparison of joint source retrieval across conditions, it avoids statistical problems due to inflated confidence intervals and does not imply a conceptual imbalance between source dimensions. Model selection criteria that take model complexity into account corroborate the new model of joint source recognition.