Concordance on negative emotion in close relationships: Transmission of emotion or assortative mating?

Two 3-wave panel studies were conducted to test for transmission of negative affect in naturally occurring dyads. In Study 1, symptoms of depression and negative affect were measured in 153 dating couples at 6-week intervals. In a similar second study, these same variables were measured in 170 college roommate dyads. Within both dating couples and roommates, symptoms of depression and negative affect were typically correlated at all points of measurement. However, structural equation analyses that controlled for prior negative affect and initial similarity on negative affect provided no evidence of emotional transmission in dating couples. There was minimal evidence for emotional transmission in roommate dyads. The intradyadic similarity in negative affect was greater than what would be expected by chance, but unrelated to the length of the relationship, as predicted by the assortative mating effect.