Do Personality Traits Interfere? Geometric Limitations of Steering in Large Language Models
Network Analysis and Social Influence Modelling (NASIM) Lab(网络分析与社会影响建模实验室);School of Physics Maths and Computing(物理数学计算学院);The University of Western Australia(西澳大学);School of Computing(计算学院);Macquarie University(麦觉瑞大学)
Personality steering in large language models (LLMs) commonly relies on injecting trait-specific steering vectors, implicitly assuming that personality traits can be controlled independently. In this work, we examine whether this assumption holds by analysing the geometric relationships between Big Five personality steering directions. We study steering vectors extracted from two model families (LLaMA-3-8B and Mistral-8B) and apply a range of geometric conditioning schemes, from unconstrained directions to soft and hard orthonormalisation. Our results show that personality steering directions exhibit substantial geometric dependence: steering one trait consistently induces changes in others, even when linear overlap is explicitly removed. While hard orthonormalisation enforces geometric independence, it does not eliminate cross-trait behavioural effects and can reduce steering strength. These findings suggest that personality traits in LLMs occupy a slightly coupled subspace, limiting fully independent trait control.
Evaluating Personality Traits in Large Language Models: Insights from Psychological Questionnaires
School of Physics, Mathematics and Computing(物理、数学与计算学院);University of Western Australia(西澳大学);School of Computing(计算机学院);School of Psychological Sciences(心理科学学院)
Neuron-based Personality Trait Induction in Large Language Models
Gaoling School of Artificial Intelligence, Renmin University of China(中国人民大学首都人工智能学院);Tongyi Lab(通义实验室);Institute of Statistics and Big Data, Renmin University of China(中国人民大学统计与大数据研究院)
Personality Vector: Modulating Personality of Large Language Models by Model Merging
Department of Human-Artificial Intelligence Interaction, Sungkyunkwan University(人类-人工智能交互系,成均馆大学);Department of Immersive Media Engineering, Sungkyunkwan University(沉浸式媒体工程系,成均馆大学)
Predicting the Big Five Personality Traits in Chinese Counselling Dialogues Using Large Language Models
Zhejiang University(浙江大学);School of Engineering, Westlake University(西湖大学工程学院);Westlake University(西湖大学);School of Early Childhood Education, Hangzhou Polytechnic(杭州职业技术学院幼儿教育学院)
BIG5-TPoT: Predicting BIG Five Personality Traits, Facets, and Items Through Targeted Preselection of Texts
The University of Maryland Applied Research Laboratory for Intelligence and Security (ARLIS)(马里兰大学应用研究实验室(情报与安全实验室));The University of Maryland (UMD)(马里兰大学)
The Dark Patterns of Personalized Persuasion in Large Language Models: Exposing Persuasive Linguistic Features for Big Five Personality Traits in LLMs Responses
Warsaw University of Technology(华沙理工大学);University of Warsaw(华沙大学)
Exploring the Impact of Personality Traits on Conversational Recommender Systems: A Simulation with Large Language Models
Chinese University of Hong Kong(香港中文大学);National University of Singapore(新加坡国立大学);Singapore Management University(新加坡管理大学);Hong Kong Baptist University(香港浸会大学);Huazhong University of Science and Technology(华中科技大学)