The Lab for Social Decision-Making & Risk

In selection decisions, decision makers often struggle to ignore irrelevant information, such as candidates' age, gender and attractiveness, which can lead to suboptimal decisions. One way to correct the effects of these irrelevant attributes is to consider them as suppressor variables, and penalize individuals who unjustifiably benefit from them. Previous research demonstrated that people have difficulties doing so. In five experiments (N = 1325), we examined the mechanism at the core of people's ability to do so. We found that triggering System 2 did not improve participants' ability to correct for this bias. The majority of those who were successful did so even when denied the opportunity to deliberate. We suggest that logic intuition—not deliberation—is the basis for successfully considering irrelevant information as suppressors. Our results are in line with a revised dual-process approach, in which solving reasoning problems can occur directly through System 1 and does not require an override by a System 2's-based process.