A longitudinal study of friendship development.

At 3-week intervals during their first term at the university, 84 male and female freshman completed questionnaires regarding their relationships with two same-sex individuals whom they had just met. Results showed that dyads which successfully developed into close friendships by the end of the fall school term differed behaviorally and attitudinally from dyads that did not progress. As the friendships developed, the intimacy level of dyadic interaction accounted for an increasing percentage of the variance in ratings of friendship intensity beyond that accounted for by the sheer quantity of interaction. Ratings of relationship benefits were consistently positively correlated with friendship intensity and increased as the relationship progressed. There were no differences in ratings of relationship costs between close and nonclose friends. Dyadic behavior patterns and attitude ratings at the end of the fall school term were good predictors of friendship status 3 months later. Motivational and situational factors were also correlated with friendship outcomes.