frb-us paper: fix the data-vintage claim, benchmark the residual against pyfrbus's own version noise - #37
Merged
Merged
Conversation
…against pyfrbus's own version noise The paper said the vendored April 2026 data was 'one release behind' because the Board's page is labelled 'Updated: May 5, 2026'. The archive at that link is in fact byte-identical to the vendored one (same SHA-256), so the claim was wrong. Adds a three-way comparison: ours vs pyfrbus 1.0.0 (6.0e-9), ours vs 1.1.1 (1.4e-8), and 1.1.1 vs 1.0.0 (1.3e-8) — the Fed's own releases differ from each other by as much as we differ from either, which is a stronger statement of the validation result than any single figure. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
|
The latest updates on your projects. Learn more about Vercel for GitHub.
|
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Two corrections to the FRB/US working paper, both from checking claims against the actual artefacts.
1. A wrong claim removed. The limitations section said the Board's pages listed a data package "already one data release ahead of the vendored vintage." The page is labelled "Updated: May 5, 2026", but the archive served from that link is byte-identical to the April vintage we vendor — same SHA-256, every member stamped 8 April 2026. There is no newer data. The paragraph now says so, with the caution that the page label tracks the page, not the artefact.
2. A stronger validation statement. Our reference is pyfrbus 1.0.0 (2022); the Board now ships 1.1.1 (2026) with the Newton solver rewritten. Since
model.xmland LONGBASE are identical between releases, comparing them isolates solver differences:The Fed's own two releases differ from each other by as much as we differ from either — so the agreement isn't an artefact of one old release, it sits at the scale of the reference implementation's own numerical noise. (Also: 1.1.1 tracks LONGBASE to 1.1e-8; ours is 5.6e-17.)
Builds clean: 36pp, zero overfull boxes, no undefined references. Companion PR merged in us-frb-model: PolicyEngine/us-frb-model#1.
🤖 Generated with Claude Code