Facial first impressions form two clusters representing approach-avoidance

Existing models of facial first impressions indicate between two and four factors that underpin all social trait judgements. Here, we submitted several large databases of these first impression ratings to unsupervised learning algorithms with the aim of clustering together faces, rather than traits, to examine the ways in which impressions may be grouped together. Experiment 1 revealed two clusters of faces that exist in both a full-dimensional,...