Self-referenced interpersonal similarity phenomena: Theoretical specification and assessment at the individual,dyadic and group levels

A basic interpersonal task is assessing if another is similar to oneself, and is even observed among prelinguistic infants. In 450 highly acquainted dyads (150 from family, friend, co-worker groups), participants judged others' similarity to themselves, and predicted others' similarity ratings of them. Assumed reciprocity and reciprocity of similarity judgments were observed; the former was much stronger than the latter. Specific others were judged as uniquely similar; in families these judgments were reciprocated. People inaccurately predicted others', and specific others', similarity judgments. Common members of these groups (key person) judged others as similar to themselves, and predicted others' reciprocated similarity judgments, although they did not. Social relations modeling showed that interpersonal similarity assessments in different groups are multiple phenomena at multiple levels of analysis and should not be treated as a single, unitary phenomenon.