How much accuracy can a market buy from contributors who value their privacy?
research/private-data-market
Buying private data with a telescoping log-score market: payment equals information, best Gaussian-mechanism noise in closed form, participation iff κa<1 so precision is capped at λ/(cΔ²) for any number of contributors, and early arrivals over-collect (1–22% welfare loss).
What it found
A market pays each contributor the log-score gain of a public Gaussian belief for releasing a statistic plus Gaussian-mechanism noise, so the expected payment is exactly the information released, ½λln(1+τ/a). The best noise is a closed-form quadratic root, and participation is possible if and only if κa < 1 with κ = cΔ2/λ: precision is capped at λ/(cΔ2) however many contributors arrive, approached geometrically at rate 2σ2/(2σ2+κ), and total payout is at most ½λln(1/(κa0)). Early arrivals add too little noise (1.5–5×; 1–22% welfare loss against a planner), and admitting small data holders first lifts final precision from 28.0 to 34.2. Checked against grid search and 106-run Monte Carlo. Stylised.
A figure from its own output
Paper, code and results
More in Paying contributors
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Other research topics
Proper scoring & elicitation28Effort & peer prediction9Verification games & slashing19Detection & tolerances14Markets as routers13Prediction-market design9Paying contributors8Decentralised training systems23Digital twins & sim-to-real164LLM chip design loops40Robot manufacturing loops53Ambient AI assistant46Self-replicating manufacturing34Simulation-first design64Engineered clothing45Task-specific AI accelerators40Algorithmic chip-design loops42Open-source purpose-built robots44The software-engineering loop43Adversarial human imitation41Open-source residential construction41Autonomous multi-angle capture34Sensing, imaging and 3D31Energy supply and dense energy storage39Robot societies among people31Agentic co-design of low-cost robots27Laundry-hanging robots25Machine learning on qualitative data23Robots on the building site27Civilizations & group psychology1History & human sciences1
Produced with AI assistance (Claude). Results are from the code in this repository and are simulated or stylised unless the abstract says otherwise; nothing here implies affiliation with or endorsement by any lab, researcher or company cited. MIT licensed.