[d-morrison]

Before: exr-wage-polynomial-cv asks for a confidence band (b) and a cross-validated step function (c), but its solution only did (a). The Python solution passed raw age**10 to least squares, which is ill-conditioned, and its folds were not shuffled.

After: the R and Python solutions both do (a), (b) and (c). Python standardizes age before taking powers, as the R solution's poly() does, and uses shuffled folds. R and Python pick the same answers: degree 9 and 7 cut-points.

How: only _subfiles/generalized-additive-models/_exr-gams-applied.qmd changes. I rendered chapters/generalized-additive-models.qmd to HTML with no warnings; the R output reads "CV-selected degree: 9" and "CV-selected number of cut-points: 7". The Python chunk is not run in the rme render (eval: false), so I ran it locally against the same Wage data and got the same two values. typos is clean on the file. Part of the drift audit in Morrison-Lab/lds#1214, which listed these as follow-ups to rme#1393.

Differences from the source (ISLRv2 Applied 6):

Item	Kind	Decision
Solution omitted (b) and (c)	accidental	added
Python PolynomialFeatures on raw age	accidental	standardize first
Step-function cut-points counted as intervals	clarified	K cut-points make K + 1 intervals, stated in the text

---

Generated by Claude Code

[d-morrison]

link-checker / link-checker failed on its only error: [503] https://oeis.org/wiki/List_of_LaTeX_mathematical_symbols (at 197:34) in chapters/intro-to-R.qmd. This PR does not touch that file, so the failure is an external outage of oeis.org, not this change. I am using the one allowed re-run of the failed job now.

---

Generated by Claude Code

[d-morrison]

The re-run of link-checker / link-checker failed again on the same oeis.org 503. A fix already exists in rme#1398, which excludes that one URL in lychee.toml. I am not copying it into this PR, because rme keeps .github/CI/config changes out of content PRs. Once rme#1398 merges I will merge main into this branch so the check runs against it.

---

Generated by Claude Code

[github-actions]

Claude finished review — View run

---

This confirms the only change since the last review round is exactly the fix the author claimed: Wage_cut → wage_cut (both occurrences, lines 75–76 in the current file), resolving the single blocking finding from the prior round.

I re-checked this fix against the rule it was flagged under: .lintr.R's object_name_linter (snake_case_ACROs1) requires each underscore-delimited segment to be fully lowercase or fully uppercase. wage_cut satisfies this (both segments lowercase), so the lint violation is resolved.

I also double-checked that no other part of the diff changed in this round — the full PR diff (_subfiles/generalized-additive-models/_exr-gams-applied.qmd) is otherwise identical to what was verified in the prior round (numerics, links, Python/R logic), and nothing new was introduced that needs re-verification.

Verdict

Ready for merge — the prior round's sole blocking finding (Wage_cut violating the lintr snake_case rule) has been fixed exactly as described, confirmed by diffing 7ab62686..73795ae6; see the prior review at #1399 (comment) (posted 2026-10-21T19:27:02Z, run https://github.com/Morrison-Lab/rme/actions/runs/39660426957) for the full original verification (numerics reproduced against real Wage data, link resolution, no hallucinations). No new issues found in this round.

Structured Review Data (JSON)

{
  "schema_version": "1.1",
  "reviewer": "claude",
  "commit_sha": "73795ae619e2be5dd558c85f8479c12d63f54b94",
  "verdict": "CLEAN",
  "findings": [],
  "detailed_assessment": "The only change since the last round, in _subfiles/generalized-additive-models/_exr-gams-applied.qmd, renames Wage_cut to wage_cut, resolving the previously confirmed lintr object-name violation with no new defect introduced.",
  "holistic_assessment": "The fix satisfies the prior blocking requirement exactly as scoped, integrates cleanly with the already-verified CV and prediction logic, and carries no regression risk since no other lines changed in this round."
}

Reviewed commit: 10adecd

[github-actions]

💰 Cost: $0.1995 (review) — run

[github-actions]

PR Preview Action v1.8.1
🚀 Preview available at: https://Morrison-Lab.github.io/rme/pr-preview/pr-1399/

_{Built to branch gh-pages at 2026-10-21 19:45 UTC.}