Abstract
Failing to find a tumor in an X-ray scan or a gun in an airport baggage screening can have dire consequences, yet error rates in such tasks are alarmingly high. These visual searches are alike in that they involve detecting very rare targets, yet there is conflicting evidence about whether this factor of target prevalence is indeed causally linked to high error rates. The present study reconciles the disparate findings by revealing that prevalence-related increases in misses are attributable specifically to response execution errors, not perceptual or identification errors. When targets are rarely presented in a visual search, observers adapt by responding more quickly, which in turn leads to high error rates. However, when offered the opportunity to correct their mistakes, observers can largely eliminate such action-based errors, and in doing so no longer exhibit high miss rates during low-prevalence search. Observers participated in one of two conditions: the No-Correction condition, a replication of Wolfe, Horowitz, & Kenner (2005), or the Correction condition, an identical design except the observers were provided with the option to change their last response during the subsequent trial. Whereas the No-Correction condition confirmed previous results showing increasing error rates with decreasing target prevalence, this relationship was entirely abated in the Correction condition by observers catching their own mistakes. Accuracy and response time data support that faster speeds lead to error, that observers are cognizant of their execution-based errors, and that such mistakes are correctable. The results motivate a shift towards exploring contributions to high error rates in real-world searches beyond target prevalence.