We judge faces in incomplete photographs as physically more attractive; this positivity bias is replicated for different types of face incompleteness, mostly specific to aesthetic judgments, stronger for male participants, & specific to human faces (as opposed to pets, flowers, & landscapes)

Orghian, Diana and Hidalgo, César, Worse Than You Think: Positivity Bias in Evaluations of Human Facial Attractiveness (April 13, 2018). http://dx.doi.org/10.2139/ssrn.3162479

Abstract: Attractive people are perceived to be healthier, wealthier, and more sociable. Yet, people often judge the attractiveness of others based on incomplete facial information. Here, we test the hypothesis that people fill in the missing information with positive inferences when judging others’ facial beauty. To test this hypothesis, we conducted five experiments where participants judged the attractiveness of human faces in complete and incomplete photographs. Our data shows that — relative to complete photographs — participants judge faces in incomplete photographs as physically more attractive. This positivity bias is: (i) replicated for different types of face incompleteness, (ii) mostly specific to aesthetic judgments, (iii) stronger for male participants, (iv) specific to human faces (as opposed to pets, flowers, and landscapes), (v) sensitive to participants’ prior expectations about the facial beauty of the people being evaluated, and, (vi) it involves a holistic processing of the faces.

Keywords: positivity bias, inference, face processing, attractiveness, configurational processing, expectations