Who benefits from debiasing?

Reasoning errors significantly impede sound decision-making. Despite advancements in debiasing interventions designed to improve reasoning, not all individuals benefit from these approaches. This study explores the individual differences that contribute to variability in debiasing success, focusing on thinking dispositions, cognitive capacities, and pre-training conflict detection. Using the two-response paradigm, we measured intuitive and deliberative responses both before and after a base-rate neglect debiasing intervention to better understand the relationship between individual differences and training effects. Participants were categorized into three groups: consistently biased (those who did not benefit from the training), improved (those who showed better performance either intuitively or deliberately after the training), and consistently correct (those who produced correct responses without needing the training). Each group differed across the measured variables, with the improved group falling between the consistently correct and consistently biased groups. Our findings indicate that thinking dispositions, such as open-minded thinking, played a more critical role in debiasing success than cognitive capacities. Although cognitive capacity does predict overall accuracy in reasoning, once thinking dispositions were taken into account, cognitive capacity did not predict the success of the training effect. We also found that conflict detection served as a signal prompting additional cognitive effort during the intervention, suggesting that the benefit from training depended on both recognizing errors and the motivation to engage in reflective thinking during the training. These findings challenge the idea that cognitive abilities are the primary drivers of reasoning improvement and emphasize the crucial role of thinking dispositions in achieving debiasing success.