AI–AI bias: Large language models favor communications generated by large language models

Proceedings of the National Academy of Sciences, Volume 122, Issue 31, August 2025. <br/>SignificanceThis study finds evidence that if we deploy LLM assistants in decision-making roles (e.g., purchasing goods, selecting academic submissions) they will implicitly favor LLM-based AI agents and LLM-assisted humans over ordinary humans as trade …