Findings on both attractiveness and memory for faces suggest that people should perceive more similarity among attractive than among unattractive faces. A multidimensional scaling approach was used to test this hypothesis in two studies. In Study 1, we derived a psychological face space from similarity ratings of attractive and unattractive Caucasian female faces. In Study 2, we derived a face space for attractive and unattractive male faces of Caucasians and non-Caucasians. Both studies confirm that attractive faces are indeed more tightly clustered than unattractive faces in people's psychological face spaces. These studies provide direct and original support for theoretical assumptions previously made in the face space and face memory literatures.
Potter, T., Corneille, O., Ruys, K. I., & Rhodes, G. (2007). “Just another pretty face”: A multidimensional scaling approach to face attractiveness and variability. Psychonomic Bulletin & Review, 14(2), 368-372. https://doi.org/10.3758/BF03194079