An AI can mimic your personality perfectly and still have absolutely no clue how to actually convince you to change your mind about something.
April 6, 2026
Original Paper
When simulations look right but causal effects go wrong: Large language models as behavioral simulators
arXiv · 2604.02458
AI-generated illustration
The Takeaway
While AI can act as a realistic 'digital twin' of a person, researchers found these simulations fail at predicting how people react to new policies or interventions. This means a model can look human on the surface while remaining a terrible guide for real-world social change.
From the abstract
Behavioral simulation is increasingly used to anticipate responses to interventions. Large language models (LLMs) enable researchers to specify population characteristics and intervention context in natural language, but it remains unclear to what extent LLMs can use these inputs to infer intervention effects. We evaluated three LLMs on 11 climate-psychology interventions using a dataset of 59,508 participants from 62 countries, and replicated the main analysis in two additional datasets (12 and