This project investigates personality extremity and uniqueness—how atypical a person’s trait profile is—and their associations with subjective and psychological well-being across cultures. Using the HEXACO model, it addresses two main goals: (1) Examining how trait extremity and uniqueness relate to well-being using variable- and person-centered approaches; (2) Investigating the cultural generalizability of these relationships across European countries (e.g., Netherlands, X, Y, Z). A final aim is to contribute the data to the GIGAPsych (https://osf.io/av32b/) open data repository, enhancing transparency and reusability in psychological science.
The scientific innovation lies in its dual methodological approach, inclusion of an underutilized model (HEXACO), and cross-cultural design. While individual traits like Neuroticism or Extraversion have established links with mental health, little is known about the role of overall personality extremity—a meta-score capturing systematic deviation from normative trait profiles. This approach offers new insight into why individuals with extreme traits may experience higher loneliness, social disconnection, and reduced well-being. The project further addresses a key gap: Past studies have used only Big Five traits to compute extremity, overlooking the Honesty-Humility dimension.