Does cloning an expert from logs recorded in a digital twin recover the expert?

What it found

Demonstrations logged as applied (actuator-clipped) actions bias a linear clone even in a perfect twin: at an actuator limit of 1 the clone gain is 0.58 against the expert’s 0.96 and its real cost is 9.8% higher, with the exact Gaussian-state gain k₀ P(|k₀x|<U) from Stein’s lemma. Twin errors act through the states they visit and can help: 0.25× noise cuts the gap to 0.002, 2× raises it to 0.75, and a loose twin limit of 3 nearly removes it. Log-state coverage narrower than half the saturation width recovers the expert, while DAgger with applied-action labels converges to a worse gain (0.5575, gap 0.169 vs 0.141). Stylised: scalar plant, population-level fit, no real logs.

A figure from its own output

Paper, code and results

• README and method
• White paper
• Experiments and results
• Code
• Tests

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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.