The more similar the better? Investigating the role of personality traits and personality similarity in student–teacher relationships in upper elementary schools

In the present study, we investigated the unique role of teachers' and students' personality traits as well as the personality (dis)similarity between personality traits of both partners in the affective quality of dyadic student–teacher relationships (i.e., closeness and conflict). To explore these associations, we used a Chinese sample of 4638 upper elementary students and their 104 class teachers who reported about their own personality traits and the quality of their mutual relationship. Using multilevel polynomial regression modeling with response surface analysis, we found that both students' and teachers' agreeableness, conscientiousness, and openness were generally positively associated with closeness and negatively associated with conflict. Neuroticism was found to be negatively associated with closeness and positively associated with conflict. In particular, for agreeableness and openness, these associations held true regardless of the informant (i.e., who reported about the levels of closeness and conflict). Regarding personality similarity, relationships were found to be closer and less conflictual when both relationship partners were similarly high in agreeableness, conscientiousness, and openness, and low in neuroticism, compared to when both teacher and student were similarly low in agreeableness, conscientiousness, and openness, and high in neuroticism. These results were evident both in student-reported and teacher-reported relationship quality. Regarding dissimilarity, we only found that a higher level of personality dissimilarity in openness was associated with less teacher-perceived conflict. Together, these findings provide a more comprehensive understanding of the role of personality traits and personality (dis)similarity in student–teacher relationships, and suggest that a focus on personality may be a promising avenue for understanding students' affective relationships with teachers.