Can LLMs Express Personality Across Cultures? Introducing CulturalPersonas for Evaluating Trait Alignment

TL;DR

This paper introduces CulturalPersonas, a large-scale benchmark for evaluating how well LLMs can express personality in culturally appropriate ways across diverse countries, addressing the gap between personality and cultural context.

Contribution

It presents the first culturally grounded benchmark with human validation for assessing LLMs' personality expression across different cultural contexts.

Findings

CulturalPersonas reduces Wasserstein distance by over 20% across models and countries.

LLMs show improved alignment with country-specific personality distributions.

CulturalPersonas elicits more culturally coherent and expressive responses.

Abstract

As LLMs become central to interactive applications, ranging from tutoring to mental health, the ability to express personality in culturally appropriate ways is increasingly important. While recent works have explored personality evaluation of LLMs, they largely overlook the interplay between culture and personality. To address this, we introduce CulturalPersonas, the first large-scale benchmark with human validation for evaluating LLMs' personality expression in culturally grounded, behaviorally rich contexts. Our dataset spans 3,000 scenario-based questions across six diverse countries, designed to elicit personality through everyday scenarios rooted in local values. We evaluate three LLMs, using both multiple-choice and open-ended response formats. Our results show that CulturalPersonas improves alignment with country-specific human personality distributions (over a 20% reduction in Wasserstein distance across models and countries) and elicits more expressive, culturally coherent outputs compared to existing benchmarks. CulturalPersonas surfaces meaningful modulated trait outputs in response to culturally grounded prompts, offering new directions for aligning LLMs to global norms of behavior. By bridging personality expression and cultural nuance, we envision that CulturalPersonas will pave the way for more socially intelligent and globally adaptive LLMs.