The dark triad traits and relationship satisfaction: Dyadic response surface analysis

The current study investigated actor and partner effects and the effects of (dis)similarity in the dark triad traits on self-reported relationship satisfaction of both members of romantic couples. We examined these effects on actual similarity, similarity of perception, and men's and women's perceived similarity.On the sample of 205 heterosexual romantic couples, we administered questionnaires for measuring self-reported and partner-reported psychopathy, Machiavellianism, and narcissism, as well as self-reported relationship satisfaction. For analyzing data, we used dyadic response surface analysis.The results corroborated our hypotheses that the dark triad traits exerted mainly negative actor and partner effects on both partners' relationship satisfaction. The effects of (dis)similarity were obtained for psychopathy and narcissism. Dissimilarity in psychopathy was related to lower men's relationship satisfaction. Dissimilarity in narcissism was related to lower, whereas similarity in this trait to higher relationship satisfaction of both partners. Generally, our findings were similar across methods and sources of assessment.The results suggest that the DT traits of both members of a romantic couple matter for judgments of their relationship satisfaction and that along with actor and partner effects, the effects of (dis)similarity in psychopathy and narcissism also contribute to their relationship satisfaction.