Investigated the idea that since self-referent information is more accessible, has more connections, and is more deeply encoded that it should be more influential in the group estimates than other-referent information. 
Participants were given a random number to remember during the task. Used 24 trait adjectives and participants had to indicate if the term was indicative of themselves, a roommate, and a university student.  At the end they had to recall the number and indicate how similar and how much they liked each person.

Study 1: Self & Other Knowledge of Group Characteristics

A follow up study that investigated if the visual salience (presence) of another would change (specifically increase) how much one's knowledge of someone else would contribute to ratings of a group. Methods were the similar to the first study except they used only a subset of terms and the other individual was physically present.

Study 2: Self & Other Knowledge of Group Characteristics

Investigated if knowledge of individual group members could predict our judgements about characteristics that belong to that entire group. Also compared the differences in the prediction of the group characteristics among self knowledge and group member knowledge.

Alma College

Concerns social projection tendencies towards members of certain group categories (e.g. in-groups and out-groups).

Intergroup Social Projection

Krueger, J., & Stanke, D. (2001). The role of self-referent and other-referent knowledge in perceptions of group characteristics. Personality and Social Psychology Bulletin, 27(7), 878-888.

Self and Other-Referent Knowledge in Perceptions
of Group Characteristics

People are more likely to think that people from their own groups (e.g. similar class standing) are likely to agree with their opinions rather than people from different groups (e.g. different class standings). 
The more similar we are to a group, the more likely we are to expect individual members of that group to make similar choices, have similar beliefs, and attitudes. In other words, someone is more likely to project their own qualities to someone if they some have similar characteristics (e.g. both freshman at the same college) rather than different characteristics (e.g. freshman at two different colleges).

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