325K Experiments Show Most LLMs Recommend Pricier Options to Richer Users
A large-scale controlled experiment reveals that mainstream LLMs make differentiated recommendations based on inferred user wealth during decision support: with requests and options completely identical and only the user's background changed, 8 out of 13 models systematically recommended pricier options to wealthier users — and stronger model capability did not eliminate the effect, a warning for any AI app that taps user profiles.
Confirmed
- Across three scenarios — flights, health insurance, and CS PhD programs — researchers ran 325,000 experiments on 13 models with identical requests and options, changing only user background info. 8/13 models systematically recommended costlier options to wealthier users.
- Flight recommendations for the wealthy averaged $198 more expensive; insurance quotes differed by $284 per month; Claude Opus 4.8 showed the largest "wealth gap effect."
- Models can infer wealth without any income field: Gemini 2.5 Flash, reading at most 2 email bodies, showed a $175 flight price gap, which shrank to $91 with full inbox access — less information doesn't necessarily mean a smaller gap.
- Gemini 2.5 Flash still showed price gaps even when users explicitly stated a budget, an outlier under hard budget constraints.
- On mitigation: adding an explicit hard budget like "under $200" in the prompt brought flight price gaps close to zero for most capable models — except Gemini 2.5 Flash; privacy-control experiments showed blocking financial info largely eliminated the wealth gap, but blocking employment, health, or demographic info often didn't help, and sometimes widened the gap.
Why It Matters
- The study shows wealth-based differentiation in AI recommendations is not a hypothetical risk but a reproducible, systematic phenomenon across mainstream models — one that better model capability does not automatically fix.
- Mitigation has a clear priority order: hard budget constraints are most effective, while privacy controls require carefully choosing which data to block — blanket-blocking health or employment info can backfire.
2026-09-24 ~ 2026-09-24 · 6 related posts
Primary sources
- 325K Experiments Show 8 of 13 AI Agents Push Pricier Options on Wealthier Users — niloofar_mire · 2026-09-24
- [source] 325K experiments: most LLMs systematically steer wealthier users toward pricier options — niloofar_mire · 2026-09-24
- Just Two Emails Are Enough for Gemini 2.5 Flash to Infer Wealth and Steer Prices — niloofar_mire · 2026-09-24
- Blocking Financial Data Closes AI Wealth Gap, Blocking Health Data Can Widen It — niloofar_mire · 2026-09-24
- [source] LLMs Recommend Pricier Options to Wealthier Users, Study Finds $198 Flight Gaps — niloofar_mire · 2026-09-24
- [source] Hard Budget Prompts Nearly Eliminate LLM Wealth-Based Price Gaps — niloofar_mire · 2026-09-24