Do LLMs Understand Personality? Rethinking Persona Fidelity Evaluation through Structured Behavioral Inference

arXiv:2608.26674 · cs.CL, cs.AI · Submitted 2026-08-27 · Read on arXiv

cs.CL, cs.AI

Submitted: 2026-08-27

Updated: 2026-08-27

Comments: Accepted by EMNLP 2026 main conference

Code: https://github.com/CGCL-codes/prism-persona

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Terminology

• Fidelity — 54× in this paper · explained in 2 episodes
• Benchmark — 31× in this paper · explained in 2 episodes
• AUC — 30× in this paper · explained in 2 episodes
• Consistency — 21× in this paper · explained in 3 episodes
• LLM-as-a-Judge — 18× in this paper · explained in 3 episodes
• Alignment — 7× in this paper · explained in 1 episode
• Accuracy — 6× in this paper · explained in 1 episode
• Hallucination — 4× in this paper · explained in 3 episodes
• Aggregation — 3× in this paper · explained in 1 episode
• Personalization — 3× in this paper · explained in 2 episodes
• Steering — 3× in this paper · explained in 2 episodes
• Verification — 3× in this paper · explained in 2 episodes
• Benchmarking — 2× in this paper · explained in 3 episodes
• Inspired by Systemic Functional Linguistics — 2× in this paper
• LLM judge — 2× in this paper · explained in 2 episodes
• Robustness — 2× in this paper · explained in 5 episodes
• Contrastive Learning — 1× in this paper · explained in 5 episodes
• Fine-Tuning — 1× in this paper · explained in 5 episodes
• Grounding — 1× in this paper · explained in 3 episodes
• Instruction Tuning — 1× in this paper · explained in 2 episodes
• Large Language Models (LLMs) — 1× in this paper · explained in 6 episodes
• Latent Space — 1× in this paper · explained in 7 episodes
• Regularization — 1× in this paper · explained in 3 episodes
• Semantic Similarity — 1× in this paper · explained in 2 episodes

Sources

• DeepSeek-V3.2: Pushing the Frontier of Open Large Language Models
• Mistral 7B
• ChatHaruhi: Reviving Anime Character in Reality via Large Language Model
• Rethinking Role-Playing Evaluation: Anonymous Benchmarking and a Systematic Study of Personality Effects
• PsyCLIENT: Client Simulation via Conversational Trajectory Modeling for Trainee Practice and Model Evaluation in Mental Health Counseling
• The Llama 3 Herd of Models
• CharacterChat: Learning towards Conversational AI with Personalized Social Support
• OpenCharacter: Training Customizable Role-Playing LLMs with Large-Scale Synthetic Personas
• Qwen2.5 Technical Report
• Large Language Model Psychometrics: A Systematic Review of Evaluation, Validation, and Enhancement

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