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.     

Intra-couple similarity in dyadic coping and partners’ adjustment to the birth of a child

Unlike individual perceptions of a couple's functioning, couple-level protective factors against poor adjustment to the birth of a child have rarely been studied. This study examined similarity or reciprocal exchanges in dyadic coping (DC) during pregnancy (T1) and at 6 weeks postpartum (T2) and its associations with both partners’ adjustment at 6–9 months postpartum (T3). Ninety-two Portuguese couples provided data on DC, internalizing symptoms, dyadic adjustment and parenting stress. An individual's perceived similarity at T1 positively predicted his or her own internalizing symptoms at T3. One partner's perceived similarity at T2 negatively predicted the other partner's internalizing symptoms and parenting stress at T3. These associations controlled for stereotype effects (i.e., similarity due to shared cultural norms and values). Both partners’ adjustment seems to benefit from unique similarity within the couple after childbirth, while complementarity in DC during pregnancy appears to be more beneficial in the long term. Our findings suggest important refinements to DC-based interventions already aimed to promote similarity in DC.