Similarity was measured by using a Euclidian distance measure. They found that the mean distance was smaller among the liked celebrities (mean distance=2.31) when compared to the disliked ones (mean distance=2.64). Thus, they perceived the liked celebrities as being more similar to each other. 

Alma College

This investigated the impacts of ratings of larger groups of liked and disliked people would have on the similarity levels. They predicted that by asking participants to think of many celebrities, they would be more likely to pick a diverse set of people; thus, influencing how similar they were all to each other. They asked participants to think of 12 celebrities they liked and disliked; however, only 4 of each were randomly selected for the participants to make comparison ratings about (e.g. Celebrity 1 is more sociable than Celebrity 2).  

Experiment 6; My Friends Are All Alike

Alves, H., Koch, A., & Unkelbach, C. (2016). My friends are all alike—the relation between liking and perceived similarity in person perception. Journal of Experimental Social Psychology, 62, 103-117.

My Friends Are All Alike

Exp. 6 Results: Similarity Levels (Alves et al., 2016)

Even when drawing from larger samples of people, we still tend to think that liked people are more similar to each other than disliked people are. In other words, this effect is not due to the fact that its easier to think of liked people with highly specific personalities and traits. 

Learn Before

Related