The Wisdom of the Crowd Can Unmask Faces

Accurately determining whether two images show the same person is a surprisingly difficult task, which becomes even harder if one or both faces are wearing medical face masks. Previous attempts to improve face matching accuracy have generally had limited success. One brief training program has been shown to improve masked face matching accuracy by 4.9%; however, this increase does not overcome the entire performance deficit caused by masks. Here we investigate whether combining independent identification decisions from different individuals can improve masked face matching performance through the Wisdom of the Crowds Effect (WoCE). Accuracy gains emerged reliably after combining decisions from 3 individuals, culminating in significant improvements of 11-26% among the largest crowds. Despite creating crowds of up to 80 people, half of the eventual improvement had already occurred in crowds of 6 individuals. The WoCE can entirely ameliorate the impairment face masks cause to unfamiliar face matching accuracy.