Personality Trait Similarity in Recently Cohabiting Couples: Partner Choice, Convergence, or Selective Breakup?

Romantic partners tend to be more similar in personality than would be expected by chance. This similarity can be due to the choice of a similar partner, partners becoming more similar to each other over time, or dissimilar couples breaking up. To examine whether these processes (choice, convergence, or breakup) explain personality trait similarities in couples, we followed a sample of 1,180 German couples (N = 2,360 individuals) from the year of moving in together up to 16 years thereafter. Using bivariate latent growth curve models, we found that couples were already similar in openness, conscientiousness, extraversion, and agreeableness in the year of moving in together. Although couples showed correlated change in conscientiousness, this did not increase similarity. Response surface analyses showed that separation risk was generally unrelated to dissimilarity. Furthermore, romantic partners did not become more dissimilar in the years before separation. Taken together, these results suggest that personality similarity in cohabiting couples is fully driven by choosing a similar partner. We discuss the implications of these findings for theory and research on personality similarity in romantic relationships.

伴侣间的人格特质往往具有更高的相似性，这一相似性超出了偶然性的预期。这种相似性可能源于对相似伴侣的选择、伴侣随时间推移变得更加相似，或是不相似的伴侣关系最终破裂。为探究这些过程（选择、趋同或破裂）是否能够解释伴侣间的人格特质相似性，我们追踪了1180对德国伴侣（共计2360位个体）从同居年份起至随后的16年内的情况。通过使用双变量潜在增长曲线模型，我们发现伴侣在同居当年的开放性、责任心、外向性和宜人性方面已经表现出相似性。尽管伴侣在责任心方面表现出相关性的变化，但这种变化并未增加他们的相似性。响应面分析显示，分离风险通常与差异无关。此外，在分离前的年份里，浪漫伴侣并未变得更加不相似。综合这些结果，我们认为同居伴侣间的人格相似性完全由选择相似伴侣所驱动。我们讨论了这些发现对浪漫关系人格相似性理论与研究的启示。