world-models 
Cheap factors, four domains: a scorecard — and why 'no single factor works' isn't 'no signal'
We put interpretable, locally-computable factors from four mechanistically-different domains — software-defect prediction, paper acceptance, AI-text detection, and a world-model physics proxy — on one shared per-factor scorecard. Predictive power has a domain-dependent ceiling, the factors don’t transfer across domains, and a single-factor reading nearly had us call an industrial benchmark a ‘collapse’ when the signal was just multivariate.