Building a readable Lean 4 theorem ladder for statistical learning theory
I’ve been building a Lean 4 project focused on formalizing parts of statistical learning theory:
Current verified results include:
- finite-class ERM bounds
- Rademacher symmetrization
- high-probability Rademacher bounds
- Sauer–Shelah / VC-dimension bridge
- finite scalar contraction
- linear predictor bounds
- finite PAC-Bayes bounds
- algorithmic stability
The project currently has:
- 45 Lean modules
- ~19.5k lines
- zero
sorry - zero custom axioms
The main goal is not just theorem proving for its own sake, but trying to make statistical learning theory more explicit and auditable:
- assumptions are attached directly to theorem signatures
- constants are machine checked
- proofs become buildable dependency chains instead of only textbook prose
I’m also trying to structure it pedagogically as a “theorem ladder”:
definitions → concentration → Rademacher → VC/PAC → stability → PAC-Bayes.
Compared to some existing Lean learning-theory work that focuses more on abstract probability infrastructure, this repo is currently more focused on readable finite-sample ML bounds and end-to-end theorem chains.
Would especially appreciate feedback from people interested in:
- ML theory
- theorem proving
- formal methods
- learning theory pedagogy
Posted May 8, 2026, 3:41 PM UTC
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