This thesis examines psychological antecedents and consequences of actual and perceived similarity between romantic relationship partners’ human values. Regarding effects of actual value similarity, previous research reached different conclusions using problematic means of analysis (i.e., difference scores and profile correlations) and diverse methods and samples. To address this problem, I conducted research using polynomial regression and response surface analysis as improved means of analysing effects of actual value similarity, and measure a broader range of values (by additionally recoding values-as-traits and traits-as-values), in two samples of relationship partners (Ns = 174 and 149 couples). My findings show that actual similarity can be beneficial for relationship quality when observed in some values, but not in others. Specifically, I find a positive effect of similarity in conscientiousness values, but also a replicable complementarity effect in benevolence values (but only when measured as traits). Regarding effects of perceived similarity, I present a novel theoretical framework to explain why perceptions of similarity in some individual differences dimensions to have more influence on relationship quality than others. This framework predicts an effect of perceived similarity in personality dimensions like values, relationship ideals, and traits to be important for relationship quality if they are informative about common goals, and if this information makes perceiving partner support plausible. Consistent with this framework, goal-informative dimensions (i.e., values and relationship ideals) were more closely linked to relationship quality than less goal-informative dimensions (i.e., traits). Furthermore, perceived goal similarity and perceived partner goal support mediated the effect of perceived value and relationship ideal similarity on relationship quality. In sum, my findings show that, while the presence and direction of the effect actual partner value congruence differs between dimensions, the effect of perceived similarity is universally positive when perceived similarity conveys information about similar goals, which is important for the coordination and the pursuit of these goals.
|Date of Award||26 May 2021|
|Supervisor||Gregory Maio (Supervisor) & Bas Verplanken (Supervisor)|