Friends In The Making: The Co-Development of Friendships and Personality

This study explores the reciprocal influence between personality and peer relationships during adolescence. The co-development of three Big Five personality traits and friendships was simulated in RSiena using a social network approach and longitudinal data on school-based friendship networks. Friendship nominations were linked to higher levels of extraversion and lower levels of agreeableness. Openness to experience predicted the number of received friendship nominations. Furthermore, friends significantly influenced personality traits, leading to greater similarity over time. The findings provide insights regarding the mechanisms of social selection and social influence among already acquainted individuals, enhancing our understanding of personality development and friendship formation in adolescence.