To detect or not to detect: A replication and extension of the three-stage model.

When faced with a decision, people generally show a bias toward heuristic processing, even if it leads to the incorrect decision, such as in the base-rate neglect task. The crucial question is whether people know that they are biased. Recently, the three-stage model (Pennycook, Fugelsang, & Koehler, 2015) suggested that detecting this bias (conflict detection) is imperfect and a consistent source of bias because some people do not recognize that they are making biased decisions. In Experiment 1, participants completed a base-rate neglect task as replication of Pennycook et al. (2015). In Experiment 2, a conditional reasoning task was added as an extension to test the boundary conditions of the model. Results in Experiment 1 indicated that detection failures were a significant source of bias. However, results in Experiment 2 on the conditional reasoning task indicated that the three-stage model may be incompatible with a complex task such as conditional reasoning, an issue explored in detail in the General discussion.

Detecting cheaters without thinking: testing the automaticity of the cheater detection module.

Evolutionary psychologists have suggested that our brain is composed of evolved mechanisms. One extensively studied mechanism is the cheater detection module. This module would make people very good at detecting cheaters in a social exchange. A vast amount of research has illustrated performance facilitation on social contract selection tasks. This facilitation is attributed to the alleged automatic and isolated operation of the module (i.e., independent of general cognitive capacity). This study, using the selection task, tested the critical automaticity assumption in three experiments. Experiments 1 and 2 established that performance on social contract versions did not depend on cognitive capacity or age. Experiment 3 showed that experimentally burdening cognitive resources with a secondary task had no impact on performance on the social contract version. However, in all experiments, performance on a non-social contract version did depend on available cognitive capacity. Overall, findings validate the automatic and effortless nature of social exchange reasoning.

The role of similarity in deductive categorical inference.

The category inclusion rule specifies that categories inherit the properties of their superordinates. For example, given that all metals are pentavalent, it can be concluded that all iron is pentavalent. Sloman (1998) showed that people do not fully endorse conclusions that follow from the category inclusion rule. He claims that people rely on the similarity between the premise and the conclusion categories (metals and iron), rather than applying the category inclusion rule. By allowing reasoners to rate their certainty for category relations (e.g., iron is metal), as well as for conclusions, the present study shows that similarity has only an indirect effect on the certainty of conclusions: Reasoners are more certain that similar categories have a category inclusion relation, and this in turn affects the certainty of conclusions based on this relation.