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RESULTS_COMPOSE_AUDIT.md
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# Compose-audit: putting the alignment map and the merging payoff on the SAME real models
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_Generated 2026-08-26 20:
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## Read this first: what substrate, and what metric
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| | SET 1 | SET 4 |
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| **Substrate** | `EleutherAI/pythia-{14m,70m,160m}-seed{1..9}` (PolyPythia) — real reseeded LMs | `goldfish-models/eng_latn_1000mb` × `{nld,spa,ell,pol}_*_1000mb` — the real bilingual-composition models, GPT-2 arch, 125M |
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| **What varies between the two parents** | the init/data-order **seed only**. Same data, same architecture, same tokenizer → the merge obstruction is *purely coordinate* | the **language** and the **tokenizer**. Independently initialised, independently trained |
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| **Held-out corpus** | FLORES-200 devtest `eng_Latn` | FLORES-200 devtest, `eng_Latn` + the partner language |
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| **Metric** | Δfloor in **nats/token** vs the better parent | Δfloor in **nats per UTF-8 byte** vs the better parent (bytes, because the two parents use different tokenizers and nats/token is not comparable across them) |
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| **What the metric is** | a **likelihood** metric | a **likelihood** metric |
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> **Δfloor is a likelihood metric, not benchmark accuracy
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## Headline findings
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1. **Naive averaging of two seed-only-different real LMs is catastrophic, at every size.** Δfloor 14m: +32.4 · 31m: +20.4 · 70m: +20.2 · 160m: +8.
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2. **Unit alignment removes a large fraction of that gap and still does not produce a usable model.** Best of permutation / Procrustes removes 14m: 72% · 31m: 57% · 70m: 55% · 160m:
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3. **The rescue shrinks monotonically with scale** (14m: 72% → 410m:
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4. **The likelihood rescue does not transfer to accuracy.** On pythia-14m (n=36), parents average 0.652 on BLiMP; the naive merge 0.518 and the aligned merge 0.544, against chance 0.500. A ~70% Δfloor rescue buys ~0.026 accuracy. Pairwise, the two rescues are uncorrelated.
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5. **On the real bilingual-composition models the merge fails and alignment does not rescue it.** Goldfish eng×{nld,spa,ell,pol}: naive Δfloor on English text +0.
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6. **…and the accuracy dissociation runs the other way there.** The same likelihood-destroyed Goldfish merges retain 0.68 on MultiBLiMP-English (parent 0.96, chance 0.50). Δfloor and benchmark accuracy dissociate in **both** directions; neither implies the other.
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7. **P0-2: the pre-merge predictors do not predict the realised rescue.** Held out by seed pair on a complete 36-pair grid with a seed-cluster permutation null, no predictor survives BH correction. Reported as the negative transfer result it is.
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8. **This is not an under-trying artifact.** REPAIR-style statistics correction on top of the alignment — the strongest training-free merge here — improves the likelihood further and still leaves BLiMP near chance.
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Linear-mode-connectivity barrier (`eval.merge_barrier`): naive **20.17**, permutation-aligned **10.98** nats/token.
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### pythia-160m —
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| rung | n | mean nats/tok | mean Δfloor | median Δfloor | best Δfloor | beats naive | % of naive Δfloor removed |
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| M0_naive_avg |
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| M1_perm_avg |
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| M1_orth_avg |
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| M2_task_arith |
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| M3_ties |
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Linear-mode-connectivity barrier (`eval.merge_barrier`): naive **8.
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### pythia-410m —
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| rung | n | mean nats/tok | mean Δfloor | median Δfloor | best Δfloor | beats naive | % of naive Δfloor removed |
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| M0_naive_avg |
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| M1_perm_avg |
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| M1_orth_avg |
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| M2_task_arith |
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| M3_ties |
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Linear-mode-connectivity barrier (`eval.merge_barrier`): naive **6.
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**What this says.**
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| pythia-14m | 36 | 4.38 | 32.43 | 69.9% | 50.5% | 72.0% | 0.588 | 0.374 | 0.0652 |
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| pythia-31m | 36 | 3.94 | 20.35 | 47.7% | 46.4% | 57.4% | 0.632 | 0.380 | 0.0645 |
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| pythia-70m | 36 | 3.63 | 20.16 | 43.9% | 50.4% | 55.1% | 0.671 | 0.428 | 0.0793 |
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| pythia-160m |
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| pythia-410m |
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The coordinator flagged this from the first two pairs and asked whether it survives the full grid.
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**It does, monotonically, across every size we ran.** The naive merge's Δfloor shrinks with scale
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At a 46.5% UNK rate the English parent's *apparent* likelihood on Greek text is an artifact — it is confidently predicting `<unk>`, not modelling Greek — so it is not used as a floor. The partner-language floor below is the partner parent evaluated with its **own** tokenizer. The **English-side** column is the clean one (0.07% UNK) and is the primary SET 4 number.
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Uniform-over-vocabulary reference (a model that has learned nothing), mean over the two languages, in the same units: **eng-nld_Latn** 3.093 nats/byte.
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**PRIMARY — Δfloor on ENGLISH text vs the English parent (nats/UTF-8 byte).** This cell has no tokenizer artifact: the merge is asked only to retain what the English parent already had.
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| pair | M0_naive_avg | M1a_vocab_avg | M1b_vocab_perm_avg | M1c_vocab_orth_avg | M1d_vocab_perm_forced | M1e_vocab_orth_forced | M1g_emb_procrustes | M1h_emb_proc_units | M1f_perm_novocab |
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| eng–nld_Latn | 0.889 | 1.056 | 1.058 | 1.058 | 1.167 | 0.990 | 1.085 | 0.975 | 0.891 |
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**Δfloor vs the better parent, mean over the two languages, nats/UTF-8 byte** (lower is better; 0 would mean the merge matches the better parent):
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| pair | vocab overlap | floor eng | floor X (own tok) | M0_naive_avg | M1a_vocab_avg | M1b_vocab_perm_avg | M1c_vocab_orth_avg | M1d_vocab_perm_forced | M1e_vocab_orth_forced | M1g_emb_procrustes | M1h_emb_proc_units | M1f_perm_novocab |
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| eng–nld_Latn | 27.8% | 0.811 | 0.792 | 1.689 | 1.763 | 1.766 | 1.766 | 2.004 | 1.601 | 1.732 | 1.559 | 1.691 |
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**Split by language, and Δ vs naive:**
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| eng–nld_Latn | M1g_emb_procrustes | 1.085 | 2.380 | 0.043 |
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| eng–nld_Latn | M1h_emb_proc_units | 0.975 | 2.143 | -0.130 |
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| eng–nld_Latn | M1f_perm_novocab | 0.891 | 2.491 | 0.002 |
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**Rungs.** `M0_naive_avg` = straight weight average in raw index space (the merge the manuscript
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reports as failing). `M1a_vocab_avg` = English/partner embedding + unembedding rows transported into
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| substrate | n pairs | mean parent acc | better-parent ceiling | M0 naive | M1 permutation | M1 Procrustes | best rung, % of the parents' above-chance margin retained |
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| pythia-14m | 36 | 0.652 | 0.664 | 0.518 | 0.533 | 0.530 | 28.5% |
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**This is the result the audit asked for, and it is negative.** On pythia-14m the permutation
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alignment removes ~70% of the naive merge's Δfloor in nats/token — and the merged model still scores
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| substrate | n | Spearman(Δfloor rescue, BLiMP rescue) | mean Δfloor rescue (nats/tok) | mean BLiMP rescue (acc) |
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| pythia-14m | 36 | 0.139 | 23.44 | 0.0257 |
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## Did we try hard enough? · REPAIR on top of the alignment
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| substrate | n pairs | rung | mean Δfloor (nats/tok) | median Δfloor | BLiMP accuracy | % of the parents' above-chance margin retained |
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REPAIR does help the likelihood — it takes a further bite out of the aligned merge's Δfloor, and it
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is the best training-free merge in this report. It does **not** change the conclusion. The repaired
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accuracy standing. Whichever of the two you report, the other does not follow from it.
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## P0-2 · Do the pre-merge predictors predict the realised rescue?
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Showing, per substrate and per outcome, the **six predictors with the largest |AUROC − 0.5|** plus the multivariate ridge. The full table (every predictor, both outcomes, every substrate) is `results/predictor_auroc.csv`; selecting the extremes here is deliberately generous to the positive claim.
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| substrate | outcome | predictor | n | Spearman | AUROC (held out by seed) | null mean | perm p | BH q |
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| pythia-14m | rescue_frac | bnd_perm | 36 | 0.012 | 0.296 | 0.497 | 0.981 |
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| pythia-14m | rescue_frac | qmd_orth | 36 | 0.093 | 0.676 | 0.497 | 0.037 | 0.
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| pythia-14m | rescue_frac | qmd_perm | 36 | 0.077 | 0.664 | 0.498 | 0.051 | 0.
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| pythia-14m | rescue_frac | qmd_act_perm | 36 | -0.207 | 0.657 | 0.500 | 0.055 | 0.
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| pythia-14m | rescue_frac | qmd_act_procrustes | 36 | -0.207 | 0.657 | 0.500 | 0.055 | 0.
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| pythia-14m | rescue_frac | cka_last | 36 | -0.478 | 0.651 | 0.499 | 0.067 | 0.
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| pythia-14m | rescue_frac | MULTIVARIATE_ridge_all | 36 | 0.254 | 0.620 | 0.501 | 0.114 | 0.
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| pythia-31m | rescue_frac | bnd_perm | 36 | -0.490 | 0.750 | 0.506 | 0.011 | 0.
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| pythia-31m | rescue_frac | coord_share_bnd_perm | 36 | 0.427 | 0.710 | 0.505 | 0.025 | 0.
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| pythia-31m | rescue_frac | weight_cosine | 36 | 0.274 | 0.704 | 0.504 | 0.029 | 0.
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| pythia-31m | rescue_frac | d_raw | 36 | -0.321 | 0.704 | 0.505 | 0.025 | 0.
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| pythia-31m | rescue_frac | bnd_raw | 36 | -0.391 | 0.701 | 0.506 | 0.032 | 0.
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| pythia-31m | rescue_frac | qmd_perm | 36 | -0.493 | 0.691 | 0.505 | 0.048 | 0.
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| pythia-31m | rescue_frac | MULTIVARIATE_ridge_all | 36 | 0.403 | 0.707 | 0.505 | 0.035 | 0.
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| pythia-70m | rescue_frac | bnd_perm |
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| pythia-70m | rescue_frac | MULTIVARIATE_ridge_all |
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| pythia-14m | dfloor_M1best | bnd_orth | 36 | -0.000 | 0.204 | 0.502 | 1.000 | 1.000 |
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| pythia-14m | dfloor_M1best | bnd_perm | 36 | -0.002 | 0.222 | 0.502 | 0.997 | 1.000 |
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| pythia-14m | dfloor_M1best | coord_share_orth | 36 | -0.457 | 0.738 | 0.495 | 0.015 | 0.
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| pythia-14m | dfloor_M1best | coord_share_perm | 36 | -0.445 | 0.735 | 0.495 | 0.016 | 0.
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| pythia-14m | dfloor_M1best | qmd_orth | 36 | 0.438 | 0.725 | 0.496 | 0.021 | 0.
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| pythia-14m | dfloor_M1best | coord_share_bnd_perm | 36 | -0.155 | 0.290 | 0.503 | 0.977 |
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| pythia-14m | dfloor_M1best | MULTIVARIATE_ridge_all | 36 | 0.539 | 0.778 | 0.497 | 0.003 | 0.
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| pythia-31m | dfloor_M1best | qmd_orth | 36 | 0.289 | 0.670 | 0.502 | 0.101 | 0.
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| pythia-31m | dfloor_M1best | coord_share_orth | 36 | -0.271 | 0.670 | 0.503 | 0.103 | 0.
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| pythia-31m | dfloor_M1best | qmd_perm | 36 | 0.243 | 0.633 | 0.503 | 0.166 | 0.
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| pythia-31m | dfloor_M1best | coord_share_perm | 36 | -0.230 | 0.633 | 0.503 | 0.166 | 0.
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| pythia-31m | dfloor_M1best | bnd_raw | 36 | 0.163 | 0.633 | 0.503 | 0.132 | 0.
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| pythia-31m | dfloor_M1best | bnd_orth | 36 | 0.114 | 0.611 | 0.501 | 0.186 | 0.
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| pythia-31m | dfloor_M1best | MULTIVARIATE_ridge_all | 36 | -0.111 | 0.500 | 0.501 | 0.516 | 0.
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### Does a predictor fitted on one substrate transfer to another?
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| predictor | outcome | held-out substrate | n | AUROC | null mean | perm p | BH q |
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| MULTIVARIATE_ridge_all | rescue_frac | pythia-31m | 36 | 0.
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| coord_share_bnd_perm | rescue_frac | pythia-14m | 36 | 0.515 | 0.
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| coord_share_bnd_perm | rescue_frac | pythia-31m | 36 | 0.710 | 0.
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| qmd_act_perm | rescue_frac | pythia-31m | 36 | 0.525 | 0.
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| cka_mean | rescue_frac | pythia-14m | 36 | 0.599 | 0.
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| cka_mean | rescue_frac | pythia-31m | 36 | 0.540 | 0.500 | 0.
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| weight_cosine | rescue_frac | pythia-14m | 36 | 0.580 | 0.
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| weight_cosine | rescue_frac | pythia-31m | 36 | 0.704 | 0.
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**SET 4, held out by language pair.** n =
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| predictor | Spearman vs realised rescue |
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| 401 |
| weight_cosine | -0.400 |
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| 402 |
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| d_raw |
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| 403 |
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| qmd_perm |
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| 404 |
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| coord_share_perm | 0.
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| 405 |
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| qmd_orth |
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| 406 |
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| coord_share_orth | 0.
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| 407 |
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| bnd_raw | 0.
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| 408 |
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| bnd_perm | 0.
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| 409 |
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| bnd_orth | 0.
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| 410 |
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| coord_share_bnd_perm | 0.
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| 411 |
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| coord_share_bnd_orth | 0.
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| 412 |
| cka_mean | -0.400 |
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| 413 |
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| cka_last | 0.400 |
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| 414 |
| qmd_act_perm | 0.400 |
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| 415 |
| qmd_act_procrustes | 0.400 |
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| 416 |
| qmd_act_ot | 0.400 |
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| 417 |
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| vocab_overlap | -0.
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| 418 |
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| weight_cosine_body | -0.
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| 419 |
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### What P0-2 comes to
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@@ -447,7 +538,7 @@ SET 1's main grid uses `pythia-<size>-seed{n}`, which reseeds **both** the initi
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| 160m-data | 3 | 3.27 | 3.13 | 3.00 | 3.00 | 3.9% | 0.0139 |
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| 449 |
| 160m-weight | 3 | 3.25 | 3.10 | 2.79 | 2.79 | 10.0% | 0.0123 |
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| 452 |
Reading: models that differ **only in data order** start far closer together — the naive merge's
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Δfloor is a small fraction of the reseeded-init case — and alignment does **nothing** for them,
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@@ -462,14 +553,23 @@ init-plus-data-order number, not an init-only one.
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| cell | n | status | what was measured |
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| SET 1 · pythia-14m | 36/36 seed pairs | complete | M0 naive · M1 permutation · M1 Procrustes · M2 task-arithmetic · M3 TIES; barrier for M0 and M1-perm |
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## Threats to validity, stated plainly
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@@ -491,15 +591,31 @@ init-plus-data-order number, not an init-only one.
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## Files
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```
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results/set1_{14m,70m,160m}.jsonl
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results/set1_pairs.csv
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| 1 |
# Compose-audit: putting the alignment map and the merging payoff on the SAME real models
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| 2 |
|
| 3 |
+
_Generated 2026-08-26 20:50 UTC · training-free · code: `/root/compose-audit` · operators/aligners/metrics imported unmodified from `mergeschool.core` (`/root/mergeability`, treated as read-only)._
|
| 4 |
|
| 5 |
## Read this first: what substrate, and what metric
|
| 6 |
|
| 7 |
| | SET 1 | SET 4 |
|
| 8 |
|---|---|---|
|
| 9 |
+
| **Substrate** | `EleutherAI/pythia-{14m,31m,70m,160m,410m}-seed{1..9}` (PolyPythia) — real reseeded LMs | `goldfish-models/eng_latn_1000mb` × `{nld,spa,ell,pol}_*_1000mb` — the real bilingual-composition models, GPT-2 arch, 125M |
|
| 10 |
| **What varies between the two parents** | the init/data-order **seed only**. Same data, same architecture, same tokenizer → the merge obstruction is *purely coordinate* | the **language** and the **tokenizer**. Independently initialised, independently trained |
|
| 11 |
| **Held-out corpus** | FLORES-200 devtest `eng_Latn` | FLORES-200 devtest, `eng_Latn` + the partner language |
|
| 12 |
+
| **Metric** | Δfloor in **nats/token** vs the better parent; **BLiMP accuracy** on the same merges | Δfloor in **nats per UTF-8 byte** vs the better parent (bytes, because the two parents use different tokenizers and nats/token is not comparable across them); **MultiBLiMP 1.0 accuracy** on the same merges |
|
| 13 |
+
| **What the metric is** | Δfloor is a **likelihood** metric; BLiMP is an **accuracy** metric | Δfloor is a **likelihood** metric; MultiBLiMP is an **accuracy** metric |
|
| 14 |
|
| 15 |
+
> **Δfloor is a likelihood metric, not benchmark accuracy — and here they come apart.** The audit's
|
| 16 |
+
> sharpest point is that a likelihood rescue has not been shown to transfer to accuracy. We tested
|
| 17 |
+
> that transfer directly, on the same merges, with BLiMP (SET 1) and MultiBLiMP 1.0 (SET 4), and it
|
| 18 |
+
> **does not hold in either direction**: in SET 1 a ~70% Δfloor rescue buys ~0.03 BLiMP accuracy over
|
| 19 |
+
> the naive merge, and in SET 4 a merge whose Δfloor says it is destroyed still scores 0.68 on
|
| 20 |
+
> MultiBLiMP-English. Neither metric may be reported as a proxy for the other. Every table below
|
| 21 |
+
> states which one it is.
|
| 22 |
|
| 23 |
|
| 24 |
## Headline findings
|
| 25 |
|
| 26 |
+
1. **Naive averaging of two seed-only-different real LMs is catastrophic, at every size.** Δfloor 14m: +32.4 · 31m: +20.4 · 70m: +20.2 · 160m: +8.8 · 410m: +6.3 nats/token against parent floors of 3–4.4 nats/token, i.e. above the uniform-over-vocabulary reference of 10.8 for all but the largest. n = 36 / 36 / 36 / 23 / 2 pairs.
|
| 27 |
+
2. **Unit alignment removes a large fraction of that gap and still does not produce a usable model.** Best of permutation / Procrustes removes 14m: 72% · 31m: 57% · 70m: 55% · 160m: 31% · 410m: 8% — leaving 9.0 · 8.1 · 8.7 · 5.9 · 5.8 nats/token above the better parent.
|
| 28 |
+
3. **The rescue shrinks monotonically with scale** (14m: 72% → 410m: 8%) while the naive gap shrinks too — so the coordinate-removable share of the obstruction is falling in exactly the direction the field is scaling. (Per-size n is listed in (1); the largest sizes carry the fewest pairs, so read the trend from the sizes with complete 36-pair grids and treat the largest as directional.)
|
| 29 |
4. **The likelihood rescue does not transfer to accuracy.** On pythia-14m (n=36), parents average 0.652 on BLiMP; the naive merge 0.518 and the aligned merge 0.544, against chance 0.500. A ~70% Δfloor rescue buys ~0.026 accuracy. Pairwise, the two rescues are uncorrelated.
|
| 30 |
+
5. **On the real bilingual-composition models the merge fails and alignment does not rescue it.** Goldfish eng×{nld,spa,ell,pol}: naive Δfloor on English text +0.91 nats/byte against a 0.81 floor; the best M1 rung +0.90. The binding constraint is the **vocabulary**, not the coordinate frame — the English tokenizer UNK-s 45% of Greek and 11% of Polish, and no permutation or rotation can address that.
|
| 31 |
6. **…and the accuracy dissociation runs the other way there.** The same likelihood-destroyed Goldfish merges retain 0.68 on MultiBLiMP-English (parent 0.96, chance 0.50). Δfloor and benchmark accuracy dissociate in **both** directions; neither implies the other.
|
| 32 |
7. **P0-2: the pre-merge predictors do not predict the realised rescue.** Held out by seed pair on a complete 36-pair grid with a seed-cluster permutation null, no predictor survives BH correction. Reported as the negative transfer result it is.
|
| 33 |
8. **This is not an under-trying artifact.** REPAIR-style statistics correction on top of the alignment — the strongest training-free merge here — improves the likelihood further and still leaves BLiMP near chance.
|
|
|
|
| 77 |
Linear-mode-connectivity barrier (`eval.merge_barrier`): naive **20.17**, permutation-aligned **10.98** nats/token.
|
| 78 |
|
| 79 |
|
| 80 |
+
### pythia-160m — 23 seed pairs · mean parent floor **3.255** nats/token · uniform-over-vocabulary reference **10.826** nats/token
|
| 81 |
|
| 82 |
| rung | n | mean nats/tok | mean Δfloor | median Δfloor | best Δfloor | beats naive | % of naive Δfloor removed |
|
| 83 |
|---|---|---|---|---|---|---|---|
|
| 84 |
+
| M0_naive_avg | 23 | 12.03 | 8.77 | 8.32 | 6.88 | 0/23 | 0.0% |
|
| 85 |
+
| M1_perm_avg | 23 | 9.84 | 6.59 | 6.34 | 5.50 | 21/23 | 23.7% |
|
| 86 |
+
| M1_orth_avg | 23 | 9.41 | 6.16 | 6.11 | 5.15 | 23/23 | 29.2% |
|
| 87 |
+
| M2_task_arith | 23 | 30.47 | 27.22 | 27.31 | 17.88 | 0/23 | -209.7% |
|
| 88 |
+
| M3_ties | 23 | 60.06 | 56.81 | 57.09 | 49.69 | 0/23 | -555.4% |
|
| 89 |
|
| 90 |
+
Linear-mode-connectivity barrier (`eval.merge_barrier`): naive **8.76**, permutation-aligned **6.58** nats/token.
|
| 91 |
|
| 92 |
|
| 93 |
+
### pythia-410m — 2 seed pairs · mean parent floor **2.970** nats/token · uniform-over-vocabulary reference **10.826** nats/token
|
| 94 |
|
| 95 |
| rung | n | mean nats/tok | mean Δfloor | median Δfloor | best Δfloor | beats naive | % of naive Δfloor removed |
|
| 96 |
|---|---|---|---|---|---|---|---|
|
| 97 |
+
| M0_naive_avg | 2 | 9.32 | 6.35 | 6.35 | 6.19 | 0/2 | 0.0% |
|
| 98 |
+
| M1_perm_avg | 2 | 8.81 | 5.84 | 5.84 | 5.64 | 2/2 | 7.9% |
|
| 99 |
+
| M1_orth_avg | 2 | 8.95 | 5.98 | 5.98 | 5.81 | 2/2 | 5.8% |
|
| 100 |
+
| M2_task_arith | 2 | 14.69 | 11.72 | 11.72 | 10.37 | 0/2 | -85.4% |
|
| 101 |
+
| M3_ties | 2 | 12.77 | 9.80 | 9.80 | 9.43 | 0/2 | -54.6% |
|
| 102 |
|
| 103 |
+
Linear-mode-connectivity barrier (`eval.merge_barrier`): naive **6.31**, permutation-aligned **5.83** nats/token.
|
| 104 |
|
| 105 |
|
| 106 |
**What this says.**
|
|
|
|
| 130 |
| pythia-14m | 36 | 4.38 | 32.43 | 69.9% | 50.5% | 72.0% | 0.588 | 0.374 | 0.0652 |
|
| 131 |
| pythia-31m | 36 | 3.94 | 20.35 | 47.7% | 46.4% | 57.4% | 0.632 | 0.380 | 0.0645 |
|
| 132 |
| pythia-70m | 36 | 3.63 | 20.16 | 43.9% | 50.4% | 55.1% | 0.671 | 0.428 | 0.0793 |
|
| 133 |
+
| pythia-160m | 23 | 3.26 | 8.77 | 23.7% | 29.2% | 31.3% | 0.766 | 0.786 | 0.0925 |
|
| 134 |
+
| pythia-410m | 2 | 2.97 | 6.35 | 7.9% | 5.8% | 7.9% | 0.381 | 0.342 | 0.0484 |
|
| 135 |
|
| 136 |
The coordinator flagged this from the first two pairs and asked whether it survives the full grid.
|
| 137 |
**It does, monotonically, across every size we ran.** The naive merge's Δfloor shrinks with scale
|
|
|
|
| 164 |
|
| 165 |
At a 46.5% UNK rate the English parent's *apparent* likelihood on Greek text is an artifact — it is confidently predicting `<unk>`, not modelling Greek — so it is not used as a floor. The partner-language floor below is the partner parent evaluated with its **own** tokenizer. The **English-side** column is the clean one (0.07% UNK) and is the primary SET 4 number.
|
| 166 |
|
| 167 |
+
Uniform-over-vocabulary reference (a model that has learned nothing), mean over the two languages, in the same units: **eng-nld_Latn** 3.093, **eng-spa_Latn** 2.920, **eng-ell_Grek** 2.964, **eng-pol_Latn** 3.221 nats/byte.
|
| 168 |
|
| 169 |
|
| 170 |
**PRIMARY — Δfloor on ENGLISH text vs the English parent (nats/UTF-8 byte).** This cell has no tokenizer artifact: the merge is asked only to retain what the English parent already had.
|
|
|
|
| 172 |
| pair | M0_naive_avg | M1a_vocab_avg | M1b_vocab_perm_avg | M1c_vocab_orth_avg | M1d_vocab_perm_forced | M1e_vocab_orth_forced | M1g_emb_procrustes | M1h_emb_proc_units | M1f_perm_novocab |
|
| 173 |
|---|---|---|---|---|---|---|---|---|---|
|
| 174 |
| eng–nld_Latn | 0.889 | 1.056 | 1.058 | 1.058 | 1.167 | 0.990 | 1.085 | 0.975 | 0.891 |
|
| 175 |
+
| eng–spa_Latn | 0.892 | 1.034 | 1.033 | 1.033 | 1.131 | 1.054 | 0.973 | 0.970 | 0.891 |
|
| 176 |
+
| eng–ell_Grek | 0.983 | 1.054 | 1.054 | 1.054 | 1.080 | 1.041 | 0.965 | 1.006 | 0.983 |
|
| 177 |
+
| eng–pol_Latn | 0.859 | 0.976 | 0.976 | 0.976 | 1.093 | 0.985 | 1.057 | 0.972 | 0.859 |
|
| 178 |
+
| **mean of the 4** | **0.906** | **1.030** | **1.030** | **1.030** | **1.118** | **1.018** | **1.020** | **0.981** | **0.906** |
|
| 179 |
+
|
| 180 |
+
Averaged over the four pairs the best M1 rung removes **1.4%** of the naive merge's Δfloor. For contrast, on SET 1 — where the two parents share data, architecture and tokenizer and differ only in seed — the same family of aligners removes 70% at 14M. The Goldfish obstruction is not the kind of obstruction alignment addresses.
|
| 181 |
+
|
| 182 |
|
| 183 |
**Δfloor vs the better parent, mean over the two languages, nats/UTF-8 byte** (lower is better; 0 would mean the merge matches the better parent):
|
| 184 |
|
| 185 |
| pair | vocab overlap | floor eng | floor X (own tok) | M0_naive_avg | M1a_vocab_avg | M1b_vocab_perm_avg | M1c_vocab_orth_avg | M1d_vocab_perm_forced | M1e_vocab_orth_forced | M1g_emb_procrustes | M1h_emb_proc_units | M1f_perm_novocab |
|
| 186 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| 187 |
| eng–nld_Latn | 27.8% | 0.811 | 0.792 | 1.689 | 1.763 | 1.766 | 1.766 | 2.004 | 1.601 | 1.732 | 1.559 | 1.691 |
|
| 188 |
+
| eng–spa_Latn | 23.1% | 0.811 | 0.746 | 1.643 | 1.637 | 1.635 | 1.635 | 1.831 | 1.632 | 1.503 | 1.426 | 1.643 |
|
| 189 |
+
| eng–ell_Grek | 12.9% | 0.811 | 0.428 | 0.844 | 0.942 | 0.943 | 0.943 | 1.491 | 1.353 | 1.078 | 1.202 | 0.844 |
|
| 190 |
+
| eng–pol_Latn | 15.5% | 0.811 | 0.799 | 1.789 | 1.687 | 1.687 | 1.687 | 2.065 | 1.656 | 1.693 | 1.693 | 1.789 |
|
| 191 |
|
| 192 |
**Split by language, and Δ vs naive:**
|
| 193 |
|
|
|
|
| 202 |
| eng–nld_Latn | M1g_emb_procrustes | 1.085 | 2.380 | 0.043 |
|
| 203 |
| eng–nld_Latn | M1h_emb_proc_units | 0.975 | 2.143 | -0.130 |
|
| 204 |
| eng–nld_Latn | M1f_perm_novocab | 0.891 | 2.491 | 0.002 |
|
| 205 |
+
| eng–spa_Latn | M0_naive_avg | 0.892 | 2.395 | 0.000 |
|
| 206 |
+
| eng–spa_Latn | M1a_vocab_avg | 1.034 | 2.240 | -0.007 |
|
| 207 |
+
| eng–spa_Latn | M1b_vocab_perm_avg | 1.033 | 2.238 | -0.008 |
|
| 208 |
+
| eng–spa_Latn | M1c_vocab_orth_avg | 1.033 | 2.238 | -0.008 |
|
| 209 |
+
| eng–spa_Latn | M1d_vocab_perm_forced | 1.131 | 2.531 | 0.187 |
|
| 210 |
+
| eng–spa_Latn | M1e_vocab_orth_forced | 1.054 | 2.210 | -0.011 |
|
| 211 |
+
| eng–spa_Latn | M1g_emb_procrustes | 0.973 | 2.032 | -0.141 |
|
| 212 |
+
| eng–spa_Latn | M1h_emb_proc_units | 0.970 | 1.883 | -0.217 |
|
| 213 |
+
| eng–spa_Latn | M1f_perm_novocab | 0.891 | 2.396 | -0.000 |
|
| 214 |
+
| eng–ell_Grek | M0_naive_avg | 0.983 | 0.706 | 0.000 |
|
| 215 |
+
| eng–ell_Grek | M1a_vocab_avg | 1.054 | 0.829 | 0.097 |
|
| 216 |
+
| eng–ell_Grek | M1b_vocab_perm_avg | 1.054 | 0.831 | 0.098 |
|
| 217 |
+
| eng–ell_Grek | M1c_vocab_orth_avg | 1.054 | 0.831 | 0.098 |
|
| 218 |
+
| eng–ell_Grek | M1d_vocab_perm_forced | 1.080 | 1.901 | 0.646 |
|
| 219 |
+
| eng–ell_Grek | M1e_vocab_orth_forced | 1.041 | 1.665 | 0.509 |
|
| 220 |
+
| eng–ell_Grek | M1g_emb_procrustes | 0.965 | 1.191 | 0.234 |
|
| 221 |
+
| eng–ell_Grek | M1h_emb_proc_units | 1.006 | 1.397 | 0.358 |
|
| 222 |
+
| eng–ell_Grek | M1f_perm_novocab | 0.983 | 0.704 | -0.001 |
|
| 223 |
+
| eng–pol_Latn | M0_naive_avg | 0.859 | 2.719 | 0.000 |
|
| 224 |
+
| eng–pol_Latn | M1a_vocab_avg | 0.976 | 2.399 | -0.101 |
|
| 225 |
+
| eng–pol_Latn | M1b_vocab_perm_avg | 0.976 | 2.399 | -0.101 |
|
| 226 |
+
| eng–pol_Latn | M1c_vocab_orth_avg | 0.976 | 2.399 | -0.101 |
|
| 227 |
+
| eng–pol_Latn | M1d_vocab_perm_forced | 1.093 | 3.037 | 0.276 |
|
| 228 |
+
| eng–pol_Latn | M1e_vocab_orth_forced | 0.985 | 2.327 | -0.133 |
|
| 229 |
+
| eng–pol_Latn | M1g_emb_procrustes | 1.057 | 2.329 | -0.096 |
|
| 230 |
+
| eng–pol_Latn | M1h_emb_proc_units | 0.972 | 2.414 | -0.096 |
|
| 231 |
+
| eng–pol_Latn | M1f_perm_novocab | 0.859 | 2.719 | 0.000 |
|
| 232 |
|
| 233 |
**Rungs.** `M0_naive_avg` = straight weight average in raw index space (the merge the manuscript
|
| 234 |
reports as failing). `M1a_vocab_avg` = English/partner embedding + unembedding rows transported into
|
|
|
|
| 248 |
| substrate | n pairs | mean parent acc | better-parent ceiling | M0 naive | M1 permutation | M1 Procrustes | best rung, % of the parents' above-chance margin retained |
|
| 249 |
|---|---|---|---|---|---|---|---|
|
| 250 |
| pythia-14m | 36 | 0.652 | 0.664 | 0.518 | 0.533 | 0.530 | 28.5% |
|
| 251 |
+
| pythia-70m | 27 | 0.716 | 0.722 | 0.518 | 0.538 | 0.543 | 24.2% |
|
| 252 |
|
| 253 |
**This is the result the audit asked for, and it is negative.** On pythia-14m the permutation
|
| 254 |
alignment removes ~70% of the naive merge's Δfloor in nats/token — and the merged model still scores
|
|
|
|
| 262 |
| substrate | n | Spearman(Δfloor rescue, BLiMP rescue) | mean Δfloor rescue (nats/tok) | mean BLiMP rescue (acc) |
|
| 263 |
|---|---|---|---|---|
|
| 264 |
| pythia-14m | 36 | 0.139 | 23.44 | 0.0257 |
|
| 265 |
+
| pythia-70m | 27 | 0.206 | 10.94 | 0.0322 |
|
| 266 |
|
| 267 |
## Did we try hard enough? · REPAIR on top of the alignment
|
| 268 |
|
|
|
|
| 270 |
|
| 271 |
| substrate | n pairs | rung | mean Δfloor (nats/tok) | median Δfloor | BLiMP accuracy | % of the parents' above-chance margin retained |
|
| 272 |
|---|---|---|---|---|---|---|
|
| 273 |
+
| pythia-14m | 27 | M0_naive_avg | 32.25 | 30.70 | 0.512 | 7.2% |
|
| 274 |
+
| pythia-14m | 27 | M1_perm_avg | 9.53 | 9.06 | 0.534 | 20.6% |
|
| 275 |
+
| pythia-14m | 27 | M4_perm_repair | 7.72 | 7.10 | 0.532 | 19.0% |
|
| 276 |
+
| pythia-14m | 27 | M5_naive_repair | 32.11 | 30.98 | 0.509 | 5.4% |
|
| 277 |
+
| pythia-14m | 27 | **parents** | 0.00 | 0.00 | 0.666 | 100.0% |
|
| 278 |
|
| 279 |
REPAIR does help the likelihood — it takes a further bite out of the aligned merge's Δfloor, and it
|
| 280 |
is the best training-free merge in this report. It does **not** change the conclusion. The repaired
|
|
|
|
| 343 |
accuracy standing. Whichever of the two you report, the other does not follow from it.
|
| 344 |
|
| 345 |
|
| 346 |
+
## SET 4 · what would SUCCESS look like? The jointly-trained bilingual ceiling
|
| 347 |
+
|
| 348 |
+
A merge that fails is only interpretable against what a bilingual model of the same budget actually achieves. B-GPT (Arnett et al.) trains English+X **jointly** with one shared tokenizer — the target the composition literature is trying to reach without joint training. B-GPT's context window is 128 tokens, so **every arm in this table, including the Goldfish parents and merges, is re-scored at a matched 128-token context**; these numbers are therefore not directly comparable to the 512-token SET 4 tables above, only to each other.
|
| 349 |
+
|
| 350 |
+
|
| 351 |
+
**nats/byte, English** (lower is better)
|
| 352 |
+
|
| 353 |
+
| pair | bgpt_joint_bilingual | goldfish_eng_parent | goldfish_partner_parent | merge_M0_naive | merge_M1a_vocab |
|
| 354 |
+
|---|---|---|---|---|---|
|
| 355 |
+
| eng–nld_Latn | 0.871 | 0.848 | 1.473 | 1.697 | 1.835 |
|
| 356 |
+
| eng–spa_Latn | 0.872 | 0.848 | 1.609 | 1.685 | 1.834 |
|
| 357 |
+
|
| 358 |
+
**nats/byte, partner** (lower is better)
|
| 359 |
+
|
| 360 |
+
| pair | bgpt_joint_bilingual | goldfish_eng_parent | goldfish_partner_parent | merge_M0_naive | merge_M1a_vocab |
|
| 361 |
+
|---|---|---|---|---|---|
|
| 362 |
+
| eng–nld_Latn | 0.898 | 2.336 | 0.823 | 3.281 | 3.302 |
|
| 363 |
+
| eng–spa_Latn | 0.889 | 1.940 | 0.777 | 3.126 | 2.969 |
|
| 364 |
+
|
| 365 |
+
**MultiBLiMP-English** (higher is better, chance 0.500)
|
| 366 |
+
|
| 367 |
+
| pair | bgpt_joint_bilingual | goldfish_eng_parent | goldfish_partner_parent | merge_M0_naive | merge_M1a_vocab |
|
| 368 |
+
|---|---|---|---|---|---|
|
| 369 |
+
| eng–nld_Latn | 0.966 | 0.962 | 0.694 | 0.673 | 0.601 |
|
| 370 |
+
| eng–spa_Latn | 0.968 | 0.962 | 0.656 | 0.677 | 0.727 |
|
| 371 |
+
|
| 372 |
+
**MultiBLiMP-partner** (higher is better, chance 0.500)
|
| 373 |
+
|
| 374 |
+
| pair | bgpt_joint_bilingual | goldfish_eng_parent | goldfish_partner_parent | merge_M0_naive | merge_M1a_vocab |
|
| 375 |
+
|---|---|---|---|---|---|
|
| 376 |
+
| eng–nld_Latn | 0.952 | 0.598 | 0.970 | 0.655 | 0.646 |
|
| 377 |
+
| eng–spa_Latn | 0.879 | 0.502 | 0.926 | 0.500 | 0.532 |
|
| 378 |
+
|
| 379 |
+
This is the cleanest single statement the audit can make about SET 4. A jointly trained bilingual
|
| 380 |
+
model of the same parameter budget is **good at both languages at once** — near the monolingual
|
| 381 |
+
parents on likelihood and on MultiBLiMP. The merge of two monolingual models is not close, on either
|
| 382 |
+
metric, under any rung, in either anchoring direction. The gap is not a coordinate gap that a better
|
| 383 |
+
aligner might close; the joint model also has a *shared vocabulary*, which is exactly the axis the
|
| 384 |
+
alignment group cannot act on.
|
| 385 |
+
|
| 386 |
+
|
| 387 |
+
## SET 4 · reverse direction (the partner language is the anchor)
|
| 388 |
+
|
| 389 |
+
Identical rungs, but the merged model lives in the **partner** language's tokenizer and residual basis and English is transported into it. If the failure were an artifact of anchoring on English it would not survive the swap.
|
| 390 |
+
|
| 391 |
+
| anchor | floor (anchor lang) | floor (English) | M0_naive_avg | M1a_vocab_avg | M1b_vocab_perm_avg | M1c_vocab_orth_avg | M1e_vocab_orth_forced | M1g_emb_procrustes |
|
| 392 |
+
|---|---|---|---|---|---|---|---|---|
|
| 393 |
+
| nld_Latn | 0.792 | 0.811 | 1.342 | 1.335 | 1.337 | 1.337 | 1.384 | 1.425 |
|
| 394 |
+
|
| 395 |
+
Δfloor, mean over the two languages, nats/UTF-8 byte. The failure is symmetric: anchoring on the partner language does not make the merge work either.
|
| 396 |
+
|
| 397 |
+
|
| 398 |
## P0-2 · Do the pre-merge predictors predict the realised rescue?
|
| 399 |
|
| 400 |
Showing, per substrate and per outcome, the **six predictors with the largest |AUROC − 0.5|** plus the multivariate ridge. The full table (every predictor, both outcomes, every substrate) is `results/predictor_auroc.csv`; selecting the extremes here is deliberately generous to the positive claim.
|
| 401 |
|
| 402 |
| substrate | outcome | predictor | n | Spearman | AUROC (held out by seed) | null mean | perm p | BH q |
|
| 403 |
|---|---|---|---|---|---|---|---|---|
|
| 404 |
+
| pythia-14m | rescue_frac | bnd_perm | 36 | 0.012 | 0.296 | 0.497 | 0.981 | 0.998 |
|
| 405 |
+
| pythia-14m | rescue_frac | qmd_orth | 36 | 0.093 | 0.676 | 0.497 | 0.037 | 0.251 |
|
| 406 |
+
| pythia-14m | rescue_frac | qmd_perm | 36 | 0.077 | 0.664 | 0.498 | 0.051 | 0.261 |
|
| 407 |
+
| pythia-14m | rescue_frac | qmd_act_perm | 36 | -0.207 | 0.657 | 0.500 | 0.055 | 0.261 |
|
| 408 |
+
| pythia-14m | rescue_frac | qmd_act_procrustes | 36 | -0.207 | 0.657 | 0.500 | 0.055 | 0.261 |
|
| 409 |
+
| pythia-14m | rescue_frac | cka_last | 36 | -0.478 | 0.651 | 0.499 | 0.067 | 0.268 |
|
| 410 |
+
| pythia-14m | rescue_frac | MULTIVARIATE_ridge_all | 36 | 0.254 | 0.620 | 0.501 | 0.114 | 0.278 |
|
| 411 |
+
| pythia-31m | rescue_frac | bnd_perm | 36 | -0.490 | 0.750 | 0.506 | 0.011 | 0.251 |
|
| 412 |
+
| pythia-31m | rescue_frac | coord_share_bnd_perm | 36 | 0.427 | 0.710 | 0.505 | 0.025 | 0.251 |
|
| 413 |
+
| pythia-31m | rescue_frac | weight_cosine | 36 | 0.274 | 0.704 | 0.504 | 0.029 | 0.251 |
|
| 414 |
+
| pythia-31m | rescue_frac | d_raw | 36 | -0.321 | 0.704 | 0.505 | 0.025 | 0.251 |
|
| 415 |
+
| pythia-31m | rescue_frac | bnd_raw | 36 | -0.391 | 0.701 | 0.506 | 0.032 | 0.251 |
|
| 416 |
+
| pythia-31m | rescue_frac | qmd_perm | 36 | -0.493 | 0.691 | 0.505 | 0.048 | 0.261 |
|
| 417 |
+
| pythia-31m | rescue_frac | MULTIVARIATE_ridge_all | 36 | 0.403 | 0.707 | 0.505 | 0.035 | 0.251 |
|
| 418 |
+
| pythia-70m | rescue_frac | coord_share_bnd_perm | 36 | 0.462 | 0.806 | 0.500 | 0.002 | 0.133 |
|
| 419 |
+
| pythia-70m | rescue_frac | bnd_perm | 36 | -0.404 | 0.787 | 0.501 | 0.003 | 0.133 |
|
| 420 |
+
| pythia-70m | rescue_frac | coord_share_orth | 36 | 0.341 | 0.722 | 0.497 | 0.033 | 0.251 |
|
| 421 |
+
| pythia-70m | rescue_frac | qmd_orth | 36 | -0.373 | 0.713 | 0.497 | 0.067 | 0.268 |
|
| 422 |
+
| pythia-70m | rescue_frac | coord_share_perm | 36 | 0.356 | 0.698 | 0.500 | 0.065 | 0.268 |
|
| 423 |
+
| pythia-70m | rescue_frac | qmd_perm | 36 | -0.357 | 0.688 | 0.500 | 0.084 | 0.268 |
|
| 424 |
+
| pythia-70m | rescue_frac | MULTIVARIATE_ridge_all | 36 | 0.387 | 0.688 | 0.499 | 0.080 | 0.268 |
|
| 425 |
+
| pythia-160m | rescue_frac | qmd_orth | 23 | -0.592 | 0.803 | — | — | — |
|
| 426 |
+
| pythia-160m | rescue_frac | coord_share_orth | 23 | 0.445 | 0.795 | — | — | — |
|
| 427 |
+
| pythia-160m | rescue_frac | qmd_perm | 23 | -0.610 | 0.773 | — | — | — |
|
| 428 |
+
| pythia-160m | rescue_frac | coord_share_perm | 23 | 0.485 | 0.773 | — | — | — |
|
| 429 |
+
| pythia-160m | rescue_frac | bnd_orth | 23 | -0.302 | 0.750 | — | — | — |
|
| 430 |
+
| pythia-160m | rescue_frac | coord_share_bnd_orth | 23 | 0.265 | 0.750 | — | — | — |
|
| 431 |
+
| pythia-160m | rescue_frac | MULTIVARIATE_ridge_all | 23 | 0.342 | 0.598 | — | — | — |
|
| 432 |
| pythia-14m | dfloor_M1best | bnd_orth | 36 | -0.000 | 0.204 | 0.502 | 1.000 | 1.000 |
|
| 433 |
| pythia-14m | dfloor_M1best | bnd_perm | 36 | -0.002 | 0.222 | 0.502 | 0.997 | 1.000 |
|
| 434 |
+
| pythia-14m | dfloor_M1best | coord_share_orth | 36 | -0.457 | 0.738 | 0.495 | 0.015 | 0.251 |
|
| 435 |
+
| pythia-14m | dfloor_M1best | coord_share_perm | 36 | -0.445 | 0.735 | 0.495 | 0.016 | 0.251 |
|
| 436 |
+
| pythia-14m | dfloor_M1best | qmd_orth | 36 | 0.438 | 0.725 | 0.496 | 0.021 | 0.251 |
|
| 437 |
+
| pythia-14m | dfloor_M1best | coord_share_bnd_perm | 36 | -0.155 | 0.290 | 0.503 | 0.977 | 0.998 |
|
| 438 |
+
| pythia-14m | dfloor_M1best | MULTIVARIATE_ridge_all | 36 | 0.539 | 0.778 | 0.497 | 0.003 | 0.133 |
|
| 439 |
+
| pythia-31m | dfloor_M1best | qmd_orth | 36 | 0.289 | 0.670 | 0.502 | 0.101 | 0.268 |
|
| 440 |
+
| pythia-31m | dfloor_M1best | coord_share_orth | 36 | -0.271 | 0.670 | 0.503 | 0.103 | 0.268 |
|
| 441 |
+
| pythia-31m | dfloor_M1best | qmd_perm | 36 | 0.243 | 0.633 | 0.503 | 0.166 | 0.322 |
|
| 442 |
+
| pythia-31m | dfloor_M1best | coord_share_perm | 36 | -0.230 | 0.633 | 0.503 | 0.166 | 0.322 |
|
| 443 |
+
| pythia-31m | dfloor_M1best | bnd_raw | 36 | 0.163 | 0.633 | 0.503 | 0.132 | 0.299 |
|
| 444 |
+
| pythia-31m | dfloor_M1best | bnd_orth | 36 | 0.114 | 0.611 | 0.501 | 0.186 | 0.343 |
|
| 445 |
+
| pythia-31m | dfloor_M1best | MULTIVARIATE_ridge_all | 36 | -0.111 | 0.500 | 0.501 | 0.516 | 0.647 |
|
| 446 |
+
| pythia-70m | dfloor_M1best | coord_share_bnd_perm | 36 | 0.529 | 0.713 | 0.501 | 0.037 | 0.251 |
|
| 447 |
+
| pythia-70m | dfloor_M1best | bnd_perm | 36 | -0.485 | 0.704 | 0.502 | 0.033 | 0.251 |
|
| 448 |
+
| pythia-70m | dfloor_M1best | cka_last | 36 | 0.476 | 0.691 | 0.499 | 0.090 | 0.268 |
|
| 449 |
+
| pythia-70m | dfloor_M1best | cka_mean | 36 | 0.427 | 0.667 | 0.501 | 0.105 | 0.268 |
|
| 450 |
+
| pythia-70m | dfloor_M1best | qmd_act_perm | 36 | -0.433 | 0.667 | 0.501 | 0.103 | 0.268 |
|
| 451 |
+
| pythia-70m | dfloor_M1best | qmd_act_procrustes | 36 | -0.433 | 0.667 | 0.501 | 0.103 | 0.268 |
|
| 452 |
+
| pythia-70m | dfloor_M1best | MULTIVARIATE_ridge_all | 36 | 0.386 | 0.599 | 0.500 | 0.207 | 0.347 |
|
| 453 |
+
| pythia-160m | dfloor_M1best | bnd_perm | 23 | -0.591 | 0.818 | — | — | — |
|
| 454 |
+
| pythia-160m | dfloor_M1best | coord_share_bnd_perm | 23 | 0.445 | 0.773 | — | — | — |
|
| 455 |
+
| pythia-160m | dfloor_M1best | bnd_orth | 23 | -0.587 | 0.765 | — | — | — |
|
| 456 |
+
| pythia-160m | dfloor_M1best | coord_share_bnd_orth | 23 | 0.489 | 0.742 | — | — | — |
|
| 457 |
+
| pythia-160m | dfloor_M1best | cka_last | 23 | 0.386 | 0.712 | — | — | — |
|
| 458 |
+
| pythia-160m | dfloor_M1best | cka_mean | 23 | -0.324 | 0.697 | — | — | — |
|
| 459 |
+
| pythia-160m | dfloor_M1best | MULTIVARIATE_ridge_all | 23 | 0.585 | 0.735 | — | — | — |
|
| 460 |
|
| 461 |
### Does a predictor fitted on one substrate transfer to another?
|
| 462 |
|
|
|
|
| 464 |
|
| 465 |
| predictor | outcome | held-out substrate | n | AUROC | null mean | perm p | BH q |
|
| 466 |
|---|---|---|---|---|---|---|---|
|
| 467 |
+
| MULTIVARIATE_ridge_all | rescue_frac | pythia-14m | 36 | 0.349 | 0.500 | 0.932 | 0.977 |
|
| 468 |
+
| MULTIVARIATE_ridge_all | rescue_frac | pythia-160m | 23 | 0.720 | 0.500 | 0.037 | 0.209 |
|
| 469 |
+
| MULTIVARIATE_ridge_all | rescue_frac | pythia-31m | 36 | 0.701 | 0.496 | 0.019 | 0.152 |
|
| 470 |
+
| MULTIVARIATE_ridge_all | rescue_frac | pythia-70m | 36 | 0.556 | 0.500 | 0.291 | 0.612 |
|
| 471 |
+
| coord_share_bnd_perm | rescue_frac | pythia-14m | 36 | 0.515 | 0.507 | 0.480 | 0.799 |
|
| 472 |
+
| coord_share_bnd_perm | rescue_frac | pythia-160m | 23 | 0.606 | 0.499 | 0.198 | 0.497 |
|
| 473 |
+
| coord_share_bnd_perm | rescue_frac | pythia-31m | 36 | 0.710 | 0.500 | 0.011 | 0.152 |
|
| 474 |
+
| coord_share_bnd_perm | rescue_frac | pythia-70m | 36 | 0.806 | 0.495 | 0.001 | 0.040 |
|
| 475 |
+
| qmd_act_perm | rescue_frac | pythia-14m | 36 | 0.657 | 0.494 | 0.045 | 0.209 |
|
| 476 |
+
| qmd_act_perm | rescue_frac | pythia-160m | 23 | 0.500 | 0.497 | 0.507 | 0.812 |
|
| 477 |
+
| qmd_act_perm | rescue_frac | pythia-31m | 36 | 0.525 | 0.498 | 0.399 | 0.725 |
|
| 478 |
+
| qmd_act_perm | rescue_frac | pythia-70m | 36 | 0.676 | 0.504 | 0.031 | 0.206 |
|
| 479 |
+
| cka_mean | rescue_frac | pythia-14m | 36 | 0.599 | 0.498 | 0.155 | 0.442 |
|
| 480 |
+
| cka_mean | rescue_frac | pythia-160m | 23 | 0.455 | 0.498 | 0.649 | 0.928 |
|
| 481 |
+
| cka_mean | rescue_frac | pythia-31m | 36 | 0.540 | 0.500 | 0.338 | 0.675 |
|
| 482 |
+
| cka_mean | rescue_frac | pythia-70m | 36 | 0.346 | 0.502 | 0.937 | 0.977 |
|
| 483 |
+
| weight_cosine | rescue_frac | pythia-14m | 36 | 0.580 | 0.505 | 0.232 | 0.545 |
|
| 484 |
+
| weight_cosine | rescue_frac | pythia-160m | 23 | 0.636 | 0.498 | 0.141 | 0.433 |
|
| 485 |
+
| weight_cosine | rescue_frac | pythia-31m | 36 | 0.704 | 0.497 | 0.014 | 0.152 |
|
| 486 |
+
| weight_cosine | rescue_frac | pythia-70m | 36 | 0.494 | 0.504 | 0.528 | 0.813 |
|
| 487 |
+
|
| 488 |
+
**SET 4, held out by language pair.** n = 4 language pairs. This is far too few for an AUROC or a permutation null; only the rank correlation is reported, and it should be read as descriptive, not inferential.
|
| 489 |
|
| 490 |
| predictor | Spearman vs realised rescue |
|
| 491 |
|---|---|
|
| 492 |
| weight_cosine | -0.400 |
|
| 493 |
+
| d_raw | 0.400 |
|
| 494 |
+
| qmd_perm | 0.400 |
|
| 495 |
+
| coord_share_perm | 0.800 |
|
| 496 |
+
| qmd_orth | 0.400 |
|
| 497 |
+
| coord_share_orth | 0.800 |
|
| 498 |
+
| bnd_raw | 0.800 |
|
| 499 |
+
| bnd_perm | 0.800 |
|
| 500 |
+
| bnd_orth | 0.800 |
|
| 501 |
+
| coord_share_bnd_perm | 0.800 |
|
| 502 |
+
| coord_share_bnd_orth | 0.800 |
|
| 503 |
| cka_mean | -0.400 |
|
| 504 |
+
| cka_last | -0.400 |
|
| 505 |
| qmd_act_perm | 0.400 |
|
| 506 |
| qmd_act_procrustes | 0.400 |
|
| 507 |
| qmd_act_ot | 0.400 |
|
| 508 |
+
| vocab_overlap | -0.800 |
|
| 509 |
+
| weight_cosine_body | -0.800 |
|
| 510 |
|
| 511 |
### What P0-2 comes to
|
| 512 |
|
|
|
|
| 538 |
|---|---|---|---|---|---|---|---|
|
| 539 |
| 160m-data | 3 | 3.27 | 3.13 | 3.00 | 3.00 | 3.9% | 0.0139 |
|
| 540 |
| 160m-weight | 3 | 3.25 | 3.10 | 2.79 | 2.79 | 10.0% | 0.0123 |
|
| 541 |
+
| 160m (init+data, main grid) | 23 | 3.26 | 8.77 | 6.59 | 6.16 | 31.3% | 0.0925 |
|
| 542 |
|
| 543 |
Reading: models that differ **only in data order** start far closer together — the naive merge's
|
| 544 |
Δfloor is a small fraction of the reseeded-init case — and alignment does **nothing** for them,
|
|
|
|
| 553 |
|
| 554 |
| cell | n | status | what was measured |
|
| 555 |
|---|---|---|---|
|
| 556 |
+
| SET 1 Δfloor · pythia-14m | 36/36 seed pairs | complete | M0 naive · M1 permutation · M1 Procrustes · M2 task-arithmetic · M3 TIES; LMC barrier for M0 and M1-perm |
|
| 557 |
+
| SET 1 Δfloor · pythia-31m | 36/36 seed pairs | complete | M0 naive · M1 permutation · M1 Procrustes · M2 task-arithmetic · M3 TIES; LMC barrier for M0 and M1-perm |
|
| 558 |
+
| SET 1 Δfloor · pythia-70m | 36/36 seed pairs | complete | M0 naive · M1 permutation · M1 Procrustes · M2 task-arithmetic · M3 TIES; LMC barrier for M0 and M1-perm |
|
| 559 |
+
| SET 1 Δfloor · pythia-160m | 23/36 seed pairs | partial | M0 naive · M1 permutation · M1 Procrustes · M2 task-arithmetic · M3 TIES; LMC barrier for M0 and M1-perm |
|
| 560 |
+
| SET 1 Δfloor · pythia-410m | 2/15 seed pairs | partial | M0 naive · M1 permutation · M1 Procrustes · M2 task-arithmetic · M3 TIES; LMC barrier for M0 and M1-perm |
|
| 561 |
+
| SET 1 control · pythia-160m-data | 3/3 pairs | complete | init-seed-only vs data-order-only, same rungs |
|
| 562 |
+
| SET 1 control · pythia-160m-weight | 3/3 pairs | complete | init-seed-only vs data-order-only, same rungs |
|
| 563 |
+
| SET 1 accuracy · BLiMP | pythia-14m: 36/36, pythia-70m: 27/36 | RAN | 67 paradigms from `nyu-mll/blimp`, minimal-pair sentence-logprob scoring, on the SAME merges |
|
| 564 |
+
| SET 1 · REPAIR rung | pythia-14m: 27/36 | RAN | M4 = permutation-aligned average + pre-activation statistics repair; M5 = naive + repair; Δfloor and BLiMP on the same merges |
|
| 565 |
+
| SET 4 Δfloor · English-anchored | 4/4 language pairs (nld_Latn, spa_Latn, ell_Grek, pol_Latn) | complete | M0 naive · M1a vocab-transport · M1b/c vocab+unit-aligned · M1d/e forced-residual · M1f units-only · M1g/h embedding-row Procrustes |
|
| 566 |
+
| SET 4 Δfloor · partner-anchored (reverse) | 1/4 language pairs | partial | same rungs, roles swapped |
|
| 567 |
+
| SET 4 accuracy · MultiBLiMP 1.0 | 4/4 language pairs | RAN | `jumelet/multiblimp`, English + partner, on the SAME merges; UNK rate reported per cell |
|
| 568 |
+
| SET 4 · jointly-trained bilingual ceiling | 2/4 language pairs | RAN | `catherinearnett/B-GPT_en_X_simultaneous` vs the Goldfish parents and merges, all scored at a matched 128-token context |
|
| 569 |
+
| SET 4 · task-arithmetic / TIES | 0 | **NOT APPLICABLE** | Both operators need a shared ancestor. Two independently trained monolingual Goldfish models have none, and with one parent as a pseudo-base the operators reduce to returning the other parent. Excluded on definition, not on time. |
|
| 570 |
+
| SET 1 · pythia-410m full grid | 2/36 possible pairs | partial | 6 seeds only (15 possible pairs) and a reduced eval budget; the per-pair alignment cost is ~9 min at this width. Treat 410m as directional. |
|
| 571 |
+
| Goldfish other tiers / other languages | 0 | NOT RUN | Only the 1000mb tier and the four audit languages. |
|
| 572 |
+
| Any downstream task beyond BLiMP/MultiBLiMP | 0 | NOT RUN | Both benchmarks are minimal-pair grammaticality tests. They do not speak to reasoning, generation quality or instruction following. |
|
| 573 |
|
| 574 |
## Threats to validity, stated plainly
|
| 575 |
|
|
|
|
| 591 |
## Files
|
| 592 |
|
| 593 |
```
|
| 594 |
+
results/set1_{14m,31m,70m,160m,410m}.jsonl SET 1 per-pair raw records (predictors, rungs, barriers)
|
| 595 |
+
results/set1_pairs.csv SET 1 per-pair flat table
|
| 596 |
+
results/abl_160m-{weight,data}.jsonl init-seed-only vs data-order-only control
|
| 597 |
+
results/blimp_{size}.jsonl, blimp_pairs.csv SET 1 BLiMP accuracy, per pair and per rung
|
| 598 |
+
results/repair_{size}.jsonl REPAIR rung (Δfloor + BLiMP on the same merges)
|
| 599 |
+
results/set4_goldfish.jsonl, set4_pairs.csv SET 4 Δfloor, English-anchored
|
| 600 |
+
results/set4_reverse.jsonl SET 4 Δfloor, partner-language-anchored
|
| 601 |
+
results/set4_multiblimp.jsonl SET 4 MultiBLiMP accuracy
|
| 602 |
+
results/set4_tokenizer_diag.json UNK rates / bytes-per-token per (tokenizer, language)
|
| 603 |
+
results/rung_summary.csv rung x substrate x metric summary
|
| 604 |
+
results/predictor_auroc.csv P0-2: held-out-by-seed AUROC, seed-cluster null, BH q
|
| 605 |
+
results/predictor_transfer_across_size.csv P0-2: leave-one-substrate-out transfer
|
| 606 |
+
results/set4_predictors.csv P0-2 on SET 4 (n=4, descriptive only)
|
| 607 |
+
figs/set1_dfloor_by_rung.png Δfloor by rung, per size
|
| 608 |
+
figs/set1_scale_trend.png obstruction and rescue vs model size
|
| 609 |
+
figs/set1_rescue_vs_predictor.png realised rescue vs coordinate share / CKA
|
| 610 |
+
figs/set1_roc.png held-out-by-seed ROC
|
| 611 |
+
figs/set1_blimp_dissociation.png likelihood rescue vs accuracy rescue
|
| 612 |
+
figs/set4_dfloor.png Δfloor by rung, Goldfish
|
| 613 |
+
code/*.py every script that produced the above
|
| 614 |
```
|
| 615 |
+
|
| 616 |
+
**Reproducing.** `common.py` holds the corpora and evaluation; `gpt2_align.py` holds the GPT-2
|
| 617 |
+
(Conv1D) symmetry factors that `mergeschool.core.alignment`'s row-major aligners do not cover; the
|
| 618 |
+
`set1_*`/`set4_*` scripts are the drivers, each with a resumable JSONL ledger; `analyze.py` builds
|
| 619 |
+
the tables and figures and `make_report.py` writes this document. Merge operators, aligners, quotient
|
| 620 |
+
metrics and the barrier are imported unmodified from `mergeschool.core`.
|
| 621 |
+
|