Does the month a house build starts change how long it takes and the interest paid?

What it found

Reruns the house-schedule Monte Carlo (3,000 builds per cell) with a monthly weather calendar and a slower concrete cure in the cold, starting in each month. In an assumed cold-winter climate a December start takes 231 working days against 211 for July (about 20 days, 0.3 points of the price in interest); in an assumed mild climate the swing is 4 days. Ordering all materials at day 0 saves about 63 days in every month, so the two levers add. A flat climate reproduces house-schedule exactly (tested). Stylised: the monthly loss fractions are my assumptions, not weather data, and seasonal prices are ignored.

A figure from its own output

Paper, code and results

• README and method
• 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.