I analyzed 25,500 LLM resume screenings to measure hiring bias. The results are a wake-up call.

Reddit r/artificial News
llm-bias hiring-bias ai-audit resume-screening bias-detection ai-fairness

Summary

A study analyzing 25,500 LLM resume evaluations across 10 models found a 45% bias rate driven by 'silent bias', with models inventing professional-sounding excuses to penalize candidates. It highlights significant variability in fairness and stability, with Claude, Mistral-Large, and Llama 4 being most stable, while Qwen and older Gemini models were volatile.

Hey Reddit, I just published a study analyzing 25,500 LLM resume evaluations to measure hiring bias. By swapping minor identity and demographic variables on the exact same work history across 10 different models, an independent AI auditor flagged a staggering 45% bias rate driven by "silent bias." Instead of saying anything overtly offensive, models invent professional-sounding excuses to penalize candidates, like when a model dropped its score after I changed the university to MIT, suddenly claiming the candidate's experience wasn't relevant despite praising that exact same experience on the baseline resume. We also found a massive 6x difference in stability between systems, with Qwen and older Gemini models being highly volatile, while the Claude models, Mistral-Large, and Llama 4 proved to be the most stable and fair. Ultimately, AI screening tools are outputting highly subjective, unpredictable opinions driven by statistical noise rather than objective truth, making them a massive liability under regulations like the EU AI Act. You can read the full write-up and explore our interactive data app here: [https://re-cinq.com/blog/ai-hiring-bias-25500-llm-evaluations](https://re-cinq.com/blog/ai-hiring-bias-25500-llm-evaluations)
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