Simulating Social Attitudes with LLMs: Accuracy, Demographic Effects, and Refusal Behavior in the Sensitive Domain of Suicide Prevention A study by Cristina J. Perez, Michael P. Vasquez Jr, Philippe Giabbanelli, and Patrick Y. Wu found that large language models (LLMs) have a mean absolute error of 23 percentage points when simulating public attitudes toward suicide prevention policies, based on 811,560 prompts using 32 questions from seven U.S. surveys (2023-2025). The researchers tested GPT-5 Nano, DeepSeek V3.2, Meta Llama 3.1 8B, and Mistral Small 24B, finding that model choice affects accuracy more than prompt framing, while refusal behavior varies sharply across models and prompt designs. Simulating Social Attitudes with LLMs: Accuracy, Demographic Effects, and Refusal Behavior in the Sensitive Domain of Suicide Prevention https://aclanthology.org/2026.nlpcss-1.12.pdf Cristina J. Perez /people/cristina-j-perez/unverified/ , Michael P. Vasquez Jr /people/michael-p-vasquez-jr/unverified/ , Philippe Giabbanelli /people/philippe-giabbanelli/ , Patrick Y. Wu /people/patrick-y-wu/unverified/ Abstract Large language models LLMs are increasingly used to simulate public opinion, yet their validity in sensitive policy domains remains underexplored. We evaluate whether LLMs can reproduce attitudes toward suicide prevention policies using 32 questions drawn from seven nationally representative U.S. surveys 2023-2025 . We systematically vary demographic conditioning race/ethnicity, gender, age, education, income, party , prompt framing direct elicitation, respondent embodiment, specialist embodiment , and model architecture GPT-5 Nano, DeepSeek V3.2, Meta Llama 3.1 8B, Mistral Small 24B . Across 811,560 prompts, the mean absolute error—the average gap between predicted and human response distributions—is 23 percentage points. We also find that LLM responses to demographic-conditioned prompts diverge substantially from prompts without demographic information. In short, what distribution LLMs draw on when generating responses to sensitive polling questions remains unclear. Model choice matters more than framing for accuracy, whereas refusal behavior varies sharply across models and prompt designs. Our findings highlight the limitations of LLMs for social simulation in the context of sensitive topics.- Anthology ID: - 2026.nlpcss-1.12 - Volume: Proceedings of the Seventh Workshop on Natural Language Processing and Computational Social Science /volumes/2026.nlpcss-1/ - Month: - July - Year: - 2026 - Address: - San Diego - Editors: Dallas Card /people/dallas-card/ , Anjalie Field /people/anjalie-field/ , Katherine Keith /people/katherine-keith/ , Julia Mendelsohn /people/julia-mendelsohn/ - Venues: NLP+CSS /venues/nlpcss/ | WS /venues/ws/ - SIG: - Publisher: - Association for Computational Linguistics - Note: - Pages: - 176–189 - Language: - URL: https://aclanthology.org/2026.nlpcss-1.12/ https://aclanthology.org/2026.nlpcss-1.12/ - DOI: 10.18653/v1/2026.nlpcss-1.12 https://doi.org/10.18653/v1/2026.nlpcss-1.12 - Cite ACL : - Cristina J. Perez, Michael P. Vasquez Jr, Philippe Giabbanelli, and Patrick Y. Wu. 2026. Simulating Social Attitudes with LLMs: Accuracy, Demographic Effects, and Refusal Behavior in the Sensitive Domain of Suicide Prevention https://aclanthology.org/2026.nlpcss-1.12/ . In Proceedings of the Seventh Workshop on Natural Language Processing and Computational Social Science , pages 176–189, San Diego. Association for Computational Linguistics. - Cite Informal : Simulating Social Attitudes with LLMs: Accuracy, Demographic Effects, and Refusal Behavior in the Sensitive Domain of Suicide Prevention https://aclanthology.org/2026.nlpcss-1.12/ Perez et al., NLP+CSS 2026 - PDF: https://aclanthology.org/2026.nlpcss-1.12.pdf https://aclanthology.org/2026.nlpcss-1.12.pdf