We gave 45 psychological questionnaires to 50 LLMs. What we found was not “personality.”

What is the “personality” of an LLM? What actually differentiates models psychometrically? Since LLMs entered public use, researchers have been giving them psychometric questionnaires, with mixed results. Their answers often do not seem to reflect the same psychological constructs these tests measure in humans. So we asked a slightly different question: What do LLM responses to psychometric questionnaires actually reflect? We analyzed responses to 45 validated psychometric questionnaires completed by 50 different LLMs.