Which uncertain input of the house-cost model drives the uncertainty in a house's price?
research/house-sobol
Which uncertain input of the house-cost model drives a house's price uncertainty? Sobol indices over every lever range, the framing share and the driver splits at once: floor area 53% of variance, storeys 19%, all framing inputs together under 1%. Index not dollars.
What it found
A variance-based (Sobol) global sensitivity analysis of house-cost, treating the ten lever ranges, the framing materials share and the assumed driver splits as random at once (4,096 base samples, bootstrap intervals). Floor area explains 53% of the price-index variance and storeys 19%; finish level, lot price and foundation type 6–9% each. The three framing inputs together explain under 1%, so the lumber saving optimised in house-plan barely moves the price of a whole house, and the assumed splits explain none alone and 1.7% through interactions. Per square foot, storeys matters more (25–27%). Stylised: the answer is relative to the assumed uniform ranges and ignores correlations.
A figure from its own output
Paper, code and results
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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.