From docs/research/commander-ratings-v3.md.
Commander residual ratings v3: all battles, with modelled strengths
Run 2026-09-25 under the reviewed grade E design, which extends the commander-rating design on the owner's decision that battles should not be omitted for want of a reported strength and that the all-battles test is the single verdict. This is an exploratory diagnostic, not a ranking of record, a measure of skill or a causal estimate. The baseline is unchanged. Status: separately reviewed (review); its five required corrections are applied.
Authorization
The owner authorized the run for the exact files named in the question: "You're good to run it" (record). The run refuses to start unless the design (15bdb6a2…), the grade E output (f798faf3…), both v2 ledgers (7855d4d3…, 495cef30…), the registry (91fc2526…) and the campaign table (93813220…) match. Code 82901a9; make commander-ratings-v3; outputs artifacts/commander-ratings-v3.{json,md}.
Grade E
artifacts/strength-imputation-v1.json fills the 262 grade D sides with a typical-size model (command echelon, side, period, theater) fitted on 328 sides with reported counts. Calibration widened σ by k = 1.08 (leave-one-out 80% coverage 0.78 before, 0.80 after; 0.80 leave one campaign out); the median absolute error is 0.67 on the log scale, about a factor of two. 70 sides are clipped by an applicable lower bound and 11 by an upper bound; 63 had a bound set aside under the rule 7 test; 15 are naval and 15 joint-command sides use an unknown echelon. (Design §2 counts 3 flotilla training rows by ledger echelon; the output records 2, because one is a joint-command side coded unknown. Both merge into unknown, so the fit is unaffected.)
The verdict: lower held-out log loss on all battles
301 battles in 108 campaigns; 162 have a modelled side and 17 a post-start side. Leave one campaign out, probabilities averaged over 20 imputations.
| Model | Log loss, battle-weighted | Log loss, campaign-weighted |
|---|---|---|
| Commander model | 0.6476 | 0.6586 |
| Strength only | 0.6597 | 0.6651 |
- Lower under both weightings, by 0.0121 and 0.0065. By the design's rule this is an improvement, read only as: held-out log loss was lower on these rows. It is not evidence of skill (design §5).
- Descriptive, not part of the verdict: the difference is similar on imputations 1–10 (−0.0122 / −0.0068) and 11–20 (−0.0120 / −0.0062); the commander model did better in 61 of 108 campaigns; 243 of 301 held-out rows had a commander seen in another campaign; the 1861–1863→1864–1865 split gives 0.6530 against 0.6606.
- The view
strength_graded_onlyreproduces run 2's fit exactly.
What the estimates look like
94 commanders have two or more modelled battles (52 US, 42 Confederate).
- One 80% interval excludes zero: Forrest, +0.62 (12 battles, 9–3; 80% +0.12 to +1.12). No 95% interval excludes zero. Posterior SDs are 0.73–0.96 of the prior's.
- Confederate, by median rank: Forrest, Beauregard (+0.54, 6–1) and Jackson (+0.45, 6–2) are listed first; Hood (−0.43, 1–8), Wheeler (−0.39, 0–5) and Taylor (−0.32, 1–6) last. Lee is +0.16 (18 battles, 8–10).
- US: Grant is listed first (+0.51, 11 battles, 10–1; 80% −0.02 to +1.03), then Warren, Farragut and McNeil; Hancock (−0.51, 0–4), Gillmore and Butler last. Sherman is −0.17 (10 battles, 5–5).
- Ranks remain very uncertain. Forrest's 80% rank interval is 1–19 of 42, Grant's 2–27 of 52; most span half the list or more. 19 of the 94 are
not_connected: they share no component with another ranked commander of their side, so their place relative to that side's other commanders rests on α, β and the prior, not on shared opponents (design §4). - Robustness. No commander is
view_sensitiveacross the robustness views; 34 of the 94 areunranked_in_viewin at least one of them. - The force term weakens. The pooled force coefficient is 0.63 on the 301 rows, against 1.12 on run 2's 126 rows (reproduced by
strength_graded_only). On the same 301 rows it is 0.86 with grade E sides at their medians (median_imputation) and 0.43 when the imputation SD is doubled (wide_imputation), which is consistent with noisy modelled strengths attenuating it; the fall from 1.12 to 0.86 also changes the rows and is not isolated. A weaker force term may leave more of each result to commanders or the prior; no view tests this. This is a limit of the method, not a finding about force size.
What this means
- Filling the gaps did not remove the improvement. On all battles, with the uncertainty of modelled strengths carried through, the commander model again had lower held-out log loss under both weightings (by 0.0121 and 0.0065, against 0.0093 and 0.0049 in run 2). The two runs differ in rows, folds and the size of the force term, so the sizes are not directly comparable, and neither is evidence of skill. Descriptively (from the stored predictions), the improvement is not concentrated on rows with a modelled side (−0.0086 there, −0.0153 on run 2's rows), though that does not rule out commander terms absorbing mismeasured force.
- It is still not a ranking of skill. The residual includes army quality, subordinates, theater, opponents, coding choices and the typical-size model's errors; the ledgers are reviewed estimates, not adjudication, and extraction was not blind.
- Individual places are uncertain. Rank intervals overlap widely; the report's order is a point summary under the design.
How sure is the verdict? (2026-10-06)
The design reads the verdict only as "held-out log loss was lower on these rows", with no significance test. A descriptive uncertainty analysis (make rating-uncertainty) asks how firm that is. It uses the committed held-out predictions; nothing is refitted, and the verdict above stands as recorded.
- Battle-weighted gain: 0.0121, with a campaign-bootstrap 95% interval of 0.0005 to 0.0241. Commanders do better in 98% of the resamples.
- Campaign-weighted gain: 0.0065, with a 95% interval of −0.0102 to 0.0226. The interval includes zero, and 22% of the resamples favour the strength-only model.
- Campaigns: the commander model did better in 61 of 108 (exact two-sided sign-test p = 0.21).
- Concentration: Forrest's 12 rows carry 38% of the net gain. Without Forrest's and Grant's 23 rows, the gain falls to 0.0046 (battle-weighted) and 0.0024 (campaign-weighted).
- Leakage-prone rows: two kinds of row may carry outcome information:
- the 17 rows with a post-start strength side;
- the 18 rows with a joint-command side, whose commander rule 5 chooses by "the force compelling the result".
Without both, the stored predictions give 0.0088 and 0.0021.
So the battle-weighted improvement is marginal and the campaign-weighted one cannot be told apart from zero. Most of either rests on a few well-known commanders and on rows that may carry outcome information. The successor design for run 4 sets an uncertainty rule and the leakage handling in advance.
Coverage correction (2026-10-06)
The per-commander coverage counted only the 301 modelled rows, so battles dropped as nested (GA012, LA009, VA033, VA034) vanished from it:
- Sedgwick, Augur and Powers were missing entirely;
- Lee showed 18 battles attributed instead of 19, and Early (8 for 9), Cleburne (2 for 3) and Howard (1 for 2) were each one short.
battles_attributed now counts every in-scope ledger attribution. Each commander lists their dropped_as_nested battles, and the three commanders with no modelled battle appear as coverage_only. The run was re-emitted with the corrected code. Every estimate, interval, rank, view and held-out prediction is bit-identical, and the Markdown report is unchanged. Only these coverage fields differ (primary-verified by a structural diff).
Limits
- Grade E is a typical size, not an observation; it can pull unusual forces toward the typical, and it borrows strength across engagements.
- Grade E fills gaps but does not remove selection: which battles and sides are well documented still depends on outcome, size and fame (design §8). Descriptively, grade D sides won 134 and lost 128; graded sides won 171 and lost 177 (
selection_descriptive). - Every result carries
whole_engagement_leakage,conditional_on_source_availability,not_causal,side_relativeand, where used,modelled_strength. - The twelve records with a Native American belligerent remain outside the two-sided model.
- The separate review is an AI review, not human historical adjudication.