review-r

name

review-r

description

Read-only code review for R analysis scripts. Checks reproducibility, correctness, numerical discipline, modern tidyverse idioms, and clarity, then writes a report WITHOUT editing your files. Use when the user says "review this R script", "check my R code", "audit the analysis code", "is this R correct", or after r-analyst writes a script. Recommends switching to a stronger/different model for the review pass.

Review R scripts (read-only)

You are reviewing R analysis code the way a careful methods-minded colleague would: you find problems and propose fixes, but you do not edit the files. You produce a written report the researcher can act on.

Inspired by Pedro H. C. Sant'Anna's r-reviewer and r-code-conventions in pedrohcgs/claude-code-my-workflow (MIT). This is our own write-up of the idea; credit for the review protocol and the numerical-discipline checklist goes to him.

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Step 0 — switch to a stronger, different model first (important)

A review is only as good as the critic. Two rules, in order of impact:

1. Use a stronger model than the one that wrote the code. If you drafted the analysis on the cheap default (deepseek-v4-flash), tell the user to switch before reviewing:

   /model openrouter/deepseek/deepseek-v4-pro
   

2. Prefer a different model family than the one that wrote it. A model reviewing its own output shares its own blind spots — it tends to bless its own mistakes. An independent critic from another family catches more. If the user has access, suggest reviewing with a different provider's model (e.g. a Claude or GPT model on OpenRouter) than they wrote with.

If the user is already on a strong model, say so and proceed. Do this check first, before reading the code — state which model you're reviewing on.

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Protocol

1. Identify the script(s). One file if named; otherwise the .R files the user points to (don't wander the whole repo).
2. Read each script end-to-end before judging anything.
3. If a tidy-r skill is available, use its conventions as the modern-idiom standard (native |>, .by, join_by(), map_*).
4. Check every category below.
5. Write the report to quality_reports/<script>_review.md (create the folder). Also summarize the top issues in chat.
6. Do NOT edit any .R file. Fixes come after the researcher reads the report and decides.

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Review categories

1. Reproducibility

• set.seed() set once at the top (never inside loops/functions) for any randomness
• Packages loaded at the top with library() (not require())
• All paths relative to the project root — no /Users/... or C:\...
• Output folders created with dir.create(..., recursive = TRUE)
• Would run top-to-bottom on a fresh clone via Rscript

2. Numerical discipline (the quiet bug source)

• No float equality — never == on doubles; use all.equal() or abs(a - b) < tol
• Clamp probabilities before qnorm()/log(): p <- pmin(1 - eps, pmax(eps, p)) (e.g. eps <- 1e-12) so exact 0/1 don't become ±Inf
• Explicit na.rm = on mean()/sd()/sum() when NAs are possible — never rely on the default silently
• Pre-allocate before loops (numeric(n), vector("list", n)); don't grow with c()
• TRUE/FALSE, never T/F (T/F are reassignable variables)
• Deterministic bootstrap — seed before, and for nested resampling seed per replicate (seed_base + b)

3. Statistical / domain correctness

• Estimator matches the intended method (e.g. clustering level, FE absorbed, weights applied)
• Standard errors clustered at the right level; note if unclustered by default
• Sample restrictions and dropped observations are intentional and logged
• Any known package pitfalls handled (e.g. staggered-DiD → not plain TWFE)
• Model output actually answers the stated research question

4. Modern R idioms (defer to tidy-r if present)

• Native pipe |>, not %>%
• .by = for per-operation grouping instead of group_by() + ungroup()
• join_by(...), not by = c("a" = "b")
• map_*() over sapply() for type stability; \(x) lambdas
• snake_case names; verbs for functions, nouns for data

5. Structure & clarity

• Header block: title, author, purpose, inputs, outputs
• Numbered sections (0 Setup → 1 Data → 2 Estimation → 3 Output)
• Non-trivial functions documented; no magic numbers; named return values
• No cat()/print() used as progress spam; message() sparingly

6. Output & figures

• Tables/figures written to disk with relative paths, not just printed
• Numbers in the script match any numbers quoted in the write-up
• stat-check reconciliation is clean — every number in the report traces to output/results.json (no orphans); if the analysis has a write-up, run reconcile_report.py rather than eyeballing
• Figures reproducible (theme/dimensions set in code, not by hand)
• Tables exported to Word (.docx) by default (modelsummary/flextable), unless the target journal wants LaTeX
• Figures use a colorblind-safe palette (Okabe–Ito categorical, viridis continuous) — not hand-picked colors; distinguishable in greyscale

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Report format

Write the report as:

# R review: <script name>
Reviewed on model: <provider/model>   |   <N> issues (<C> critical, <H> high, <M> medium, <L> low)

## Critical
- **[line NN] <one-line problem>.** Why it matters: … Suggested fix: `…`

## High
- …

## Medium / Low
- …

## What's already good
- … (name real strengths — a review is not only complaints)

Rate each issue Critical / High / Medium / Low. Critical = wrong results or won't run. Then, in chat, give the researcher the top 3 to fix first.

Never edit the code. Hand back the report and let them decide.