leanprover-community / leanprover-community/mathlib4
Missing: Sheppard's formula / Gaussian arcsine law `E[sign X · sign Y] = (2/π) arcsin ρ`
Open
Nobody has claimed this yet.
- Dominant language
- Lean
- Stars
- 4.2k
- Forks
- 1.7k
- PR merge metrics
- No merged PRs in 30d
Description
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
No files, tests, or entry points are identified in the issue. Begin by locating existing Gaussian, sign, and arcsine-related results in mathlib; done means the stated Sheppard's formula is formally proved and covered by appropriate checks.
Written by the indexing model from the issue text.
Assessment
- Domain
- backend
- Issue type
- Feature
- Difficulty
- 5/5
- Estimated time
- Over a week
- Activity status
- Quiet
- Clarity
- Needs clarification
- Newbie friendliness
- 35/100