File size: 16,745 Bytes
13aaf2d
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
import os, sys, json, glob, math
sys.path.insert(0, "/root/compose-audit")
from common import *
R = "/root/compose-audit/results"


def load(pat):
    rows = []
    for fp in sorted(glob.glob(f"{R}/{pat}")):
        for line in open(fp):
            try: rows.append(json.loads(line))
            except Exception: pass
    return rows


def md_table(headers, rows):
    out = ["| " + " | ".join(headers) + " |", "|" + "|".join(["---"] * len(headers)) + "|"]
    for r in rows:
        out.append("| " + " | ".join(str(x) for x in r) + " |")
    return "\n".join(out)


def fmt(x, n=3):
    try:
        if x is None or (isinstance(x, float) and not math.isfinite(x)): return "—"
        return f"{x:.{n}f}"
    except Exception:
        return str(x)


set1 = load("set1_*.jsonl")
set4 = load("set4_goldfish.jsonl")
VOCAB = {"14m": 50304, "70m": 50304, "160m": 50304}
sizes = sorted({r["size"] for r in set1}, key=lambda s: int(s[:-1]))

# ---------------- SET1 rung table
rung_rows, mdtabs = [], []
for sz in sizes:
    sub = [r for r in set1 if r["size"] == sz]
    d0 = np.array([r["rungs"]["M0_naive_avg"]["delta_floor"] for r in sub])
    floor = np.mean([r["floor"] for r in sub])
    keys = list(sub[0]["rungs"])
    body = []
    for k in keys:
        d = np.array([r["rungs"][k]["delta_floor"] for r in sub if k in r["rungs"]])
        nll = np.array([r["rungs"][k]["nll"] for r in sub if k in r["rungs"]])
        body.append([k, len(d), fmt(nll.mean(), 2), fmt(d.mean(), 2), fmt(np.median(d), 2),
                     fmt(d.min(), 2), f"{int((d < d0).sum())}/{len(d)}",
                     fmt(np.mean(1 - d / d0) * 100, 1) + "%"])
        rung_rows.append({"set": "SET1", "substrate": f"pythia-{sz}", "rung": k, "n_pairs": len(d),
                          "mean_nll": float(nll.mean()), "mean_dfloor": float(d.mean()),
                          "median_dfloor": float(np.median(d)), "min_dfloor": float(d.min()),
                          "n_better_than_naive": int((d < d0).sum()),
                          "mean_pct_of_naive_dfloor_removed": float(np.mean(1 - d / d0) * 100)})
    bn = np.mean([r["barrier_naive"]["barrier"] for r in sub if "barrier_naive" in r])
    bp = np.mean([r["barrier_perm"]["barrier"] for r in sub if "barrier_perm" in r])
    mdtabs.append((sz, len(sub), floor, math.log(VOCAB.get(sz, 50304)), bn, bp,
                   md_table(["rung", "n", "mean nats/tok", "mean Δfloor", "median Δfloor",
                             "best Δfloor", "beats naive", "% of naive Δfloor removed"], body)))

# ---------------- write
L = []
L.append("# Compose-audit: putting the alignment map and the merging payoff on the SAME real models\n")
L.append(f"_Generated {time.strftime('%Y-%m-%d %H:%M UTC')} · training-free · "
         "code: `/root/compose-audit` · operators/aligners/metrics imported unmodified from "
         "`mergeschool.core` (`/root/mergeability`, treated as read-only)._\n")

L.append("""## Read this first: what substrate, and what metric

| | SET 1 | SET 4 |
|---|---|---|
| **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 |
| **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 |
| **Held-out corpus** | FLORES-200 devtest `eng_Latn` | FLORES-200 devtest, `eng_Latn` + the partner language |
| **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) |
| **What the metric is** | a **likelihood** metric | a **likelihood** metric |

> **Δfloor is a likelihood metric, not benchmark accuracy.** Nothing below shows that a likelihood
> rescue transfers to BLiMP/MultiBLiMP accuracy, or to any downstream task. The audit's sharpest
> point — *recovery is not success* — is **not** settled by these numbers and must not be written up
> as if it were. No accuracy benchmark was run inside this window (see Coverage).
""")

if set1:
    L.append("\n## SET 1 · PolyPythia seed-merge (the pure-coordinate ceiling)\n")
    L.append(f"C(9,2) = 36 seed pairs per size. Predictors are computed **before** any merge; the "
             f"alignment factors (residual basis map fitted from activations on the shared corpus, "
             f"free MLP hidden axis, attention heads) are each accepted only if they do not increase "
             f"the scale-free block-normalised weight distance.\n")
    for sz, n, floor, unif, bn, bp, tab in mdtabs:
        L.append(f"\n### pythia-{sz}{n} seed pairs · mean parent floor **{floor:.3f}** nats/token · "
                 f"uniform-over-vocabulary reference **{unif:.3f}** nats/token\n")
        L.append(tab)
        L.append(f"\nLinear-mode-connectivity barrier (`eval.merge_barrier`): naive **{bn:.2f}**, "
                 f"permutation-aligned **{bp:.2f}** nats/token.\n")
    L.append("""
**What this says.**

1. **Naive averaging of two same-data, same-architecture, same-tokenizer models that differ only in
   seed is catastrophic.** The merged model's loss is tens of nats/token above the better parent —
   far above the uniform-over-vocabulary reference, i.e. the merge is not a degraded model, it is a
   destroyed one. This is the pure-coordinate case: there is no data, architecture or tokenizer
   difference left to blame.
2. **Unit alignment removes a large, highly consistent fraction of that gap** — the permutation rung
   beats naive on essentially every pair — **and still does not produce a usable model.** The aligned
   merge remains above the uniform reference at every size we ran. So on real LMs at this scale,
   alignment *predicts and reduces* the obstruction without *enabling* the merge. Reporting the
   reduction as "merging works once you align" would be wrong.
3. **Task-arithmetic and TIES are not applicable here and the numbers show it.** PolyPythia seeds are
   independent re-initialisations: `EleutherAI/pythia-<size>` is *not* a shared ancestor, so the
   "task vectors" those operators subtract are not task vectors. Their rows are reported only to
   document that the shared-base family degenerates when the base is not shared.
4. The linear interpolation path has its minimum at the endpoints for every pair — there is no
   interior t that beats the better parent, aligned or not.
""")

if set4:
    L.append("\n## SET 4 · Goldfish monolingual → bilingual merge (the real composition models)\n")
    rung_keys = list(set4[0]["rungs"])
    hdr = ["pair", "vocab overlap", "floor eng", "floor X"] + [k for k in rung_keys]
    body = []
    for r in set4:
        row = [f"eng–{r['lang']}", f"{r['predictors']['vocab_overlap']:.1%}",
               fmt(r["floor_eng"]), fmt(r["floor_x"])]
        for k in rung_keys:
            row.append(fmt(r["rungs"][k]["delta_floor_mean"]))
        body.append(row)
        for k in rung_keys:
            rung_rows.append({"set": "SET4", "substrate": f"goldfish eng-{r['lang']}", "rung": k,
                              "n_pairs": 1, "mean_nll": float(r["rungs"][k]["eng"]["nats_per_byte"]),
                              "mean_dfloor": float(r["rungs"][k]["delta_floor_mean"]),
                              "median_dfloor": float(r["rungs"][k]["delta_floor_mean"]),
                              "min_dfloor": float(r["rungs"][k]["delta_floor_mean"]),
                              "n_better_than_naive": int(r["rungs"][k]["delta_floor_mean"] <
                                                         r["rungs"]["M0_naive_avg"]["delta_floor_mean"]),
                              "mean_pct_of_naive_dfloor_removed": float(
                                  100 * (1 - r["rungs"][k]["delta_floor_mean"] /
                                         r["rungs"]["M0_naive_avg"]["delta_floor_mean"]))})
    # uniform-over-vocabulary reference in nats/byte, per language pair
    uref = []
    for r in set4:
        v = r["rungs"]["M0_naive_avg"]
        be = math.log(51200) * v["eng"]["nats_per_byte"] / v["eng"]["nats_per_token"]
        bx = math.log(51200) * v["x"]["nats_per_byte"] / v["x"]["nats_per_token"]
        uref.append([f"eng-{r['lang']}", fmt(0.5 * (be + bx))])
    L.append("Uniform-over-vocabulary reference (a model that has learned nothing), mean over the two "
             "languages, in the same units: " +
             ", ".join(f"**eng-{r['lang']}** {u[1]}" for r, u in zip(set4, uref)) + " nats/byte.\n")
    L.append("**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):\n")
    L.append(md_table(hdr, body))
    body2 = []
    for r in set4:
        for k in rung_keys:
            body2.append([f"eng–{r['lang']}", k, fmt(r["rungs"][k]["delta_floor_eng"]),
                          fmt(r["rungs"][k]["delta_floor_x"]),
                          fmt(r["rungs"][k]["delta_floor_mean"] -
                              r["rungs"]["M0_naive_avg"]["delta_floor_mean"])])
    L.append("\n**Split by language, and Δ vs naive:**\n")
    L.append(md_table(["pair", "rung", "Δfloor eng", "Δfloor X", "Δ vs naive (mean)"], body2))
    L.append("""
**Rungs.** `M0_naive_avg` = straight weight average in raw index space (the merge the manuscript
reports as failing). `M1a_vocab_avg` = English/partner embedding + unembedding rows transported into
the English tokenizer's id space over shared surface forms, ids absent from the partner vocabulary
left at English's own row so the average over them is a no-op. `M1b/M1c` add the unit alignment
(residual-basis map fitted from **parallel** FLORES sentence representations — rows matched across
languages by sentence id — plus the free MLP hidden axis and the attention-head permutation), under
permutation and under Procrustes respectively, each factor accepted only if it does not increase the
block-normalised weight distance. `M1d/M1e` force the residual factor in regardless of that test.
`M1f_perm_novocab` isolates the unit alignment with **no** vocabulary transport.
""")

L.append("\n## P0-2 · Do the pre-merge predictors predict the realised rescue?\n")
if os.path.exists(f"{R}/predictor_auroc.csv"):
    rows = [l.rstrip("\n").split(",") for l in open(f"{R}/predictor_auroc.csv")]
    hdr, dat = rows[0], rows[1:]
    ix = {h: i for i, h in enumerate(hdr)}
    body = []
    for d in dat:
        body.append([d[ix["substrate"]], d[ix["predictor"]], d[ix["n_pairs"]],
                     fmt(float(d[ix["spearman_rescue"]]) if d[ix["spearman_rescue"]] else None),
                     fmt(float(d[ix["auroc_heldout_by_seed"]]) if d[ix["auroc_heldout_by_seed"]] else None),
                     fmt(float(d[ix["perm_null_mean"]]) if d[ix["perm_null_mean"]] else None),
                     fmt(float(d[ix["perm_null_p"]]) if d[ix["perm_null_p"]] else None),
                     fmt(float(d[ix["bh_q"]]) if d[ix["bh_q"]] else None)])
    L.append("Outcome = **realised rescue** = the fraction of the naive Δfloor that the best M1 rung "
             "removes. Label = above the within-size median. Held out **by seed**: fold *k* is every "
             "pair touching seed *k*, trained on the pairs touching neither, so the predictor's sign "
             "(and, for the multivariate row, its coefficients) never see the held-out pairs. Null = "
             "**seed-cluster permutation** (2000 draws): permute the seed identities and re-map each "
             "pair's outcome to the permuted pair, leaving the predictor vector untouched — this "
             "preserves the pair-dependence structure that a plain label shuffle destroys. "
             "BH-corrected across the predictor family.\n")
    L.append(md_table(["substrate", "predictor", "n", "Spearman", "AUROC (held out by seed)",
                       "null mean", "perm p", "BH q"], body))
if os.path.exists(f"{R}/set4_predictors.csv"):
    rows = [l.rstrip("\n").split(",") for l in open(f"{R}/set4_predictors.csv")]
    hdr, dat = rows[0], rows[1:]
    ix = {h: i for i, h in enumerate(hdr)}
    L.append("\n**SET 4, held out by language pair.** n = %d 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.\n" % len(set4))
    L.append(md_table(["predictor", "Spearman vs realised rescue"],
                      [[d[ix["predictor"]], fmt(float(d[ix["spearman_rescue"]]) if d[ix["spearman_rescue"]] else None)]
                       for d in dat]))

# coverage
L.append("\n## Coverage — what ran and what did not\n")
cov = []
for sz in ["14m", "70m", "160m"]:
    n = len([r for r in set1 if r["size"] == sz])
    cov.append([f"SET 1 · pythia-{sz}", f"{n}/36 seed pairs", "complete" if n == 36 else ("partial" if n else "NOT RUN"),
                "M0 naive · M1 permutation · M1 Procrustes · M2 task-arithmetic · M3 TIES; barrier for M0 and M1-perm"])
langs = [r["lang"] for r in set4]
cov.append(["SET 4 · goldfish eng×X", f"{len(set4)}/4 language pairs ({', '.join(langs) or '—'})",
            "complete" if len(set4) == 4 else ("partial" if set4 else "NOT RUN"),
            "M0 naive · M1a vocab-transport · M1b/c vocab+unit-aligned (perm/Procrustes) · M1d/e forced-residual · M1f unit-aligned only"])
cov.append(["BLiMP / MultiBLiMP accuracy", "0", "**NOT RUN**",
            "No benchmark harness was close to wired inside this window. Deliberately not built from scratch. The Δfloor results below therefore say nothing about accuracy."])
cov.append(["B-GPT joint bilingual reference", "0", "**NOT RUN**", "Out of window; the merged models are not compared against a jointly-trained bilingual ceiling."])
cov.append(["Goldfish 160m/other tiers, other language pairs", "0", "NOT RUN", "Only the 1000mb tier and the four audit languages."])
L.append(md_table(["cell", "n", "status", "what was measured"], cov))

L.append("""
## Threats to validity, stated plainly

- **Likelihood ≠ accuracy.** Repeated because it is the single most load-bearing caveat here.
- **SET 1's held-out corpus is FLORES-200 English devtest**, not a Pile validation split. It is
  genuinely held out from PolyPythia training, but it is out-of-domain, so the absolute nats/token
  floors are higher than a Pile-val number would be. Δfloor is a *difference* against parents
  measured on the same corpus, so the comparison between rungs is unaffected.
- **SET 4's nats/byte is comparable across tokenizers but not free of tokenizer effects**: block
  boundaries fall at different places for different tokenizers, and each block's first token is
  unscored. With ~30k tokens per evaluation this is a sub-1% effect.
- **The alignment search is over the permutation group (residual basis, MLP hidden axis, attention
  heads) and its orthogonal relaxation.** It is not the full symmetry group, and the residual factor
  is fitted from a finite activation sample. A better aligner could raise the M1 rungs; nothing here
  bounds how far.
- **SET 4's n = 4 language pairs.** Any predictor claim on that substrate is descriptive.
""")

L.append("\n## Files\n")
L.append("""```
results/set1_{14m,70m,160m}.jsonl   per-pair raw records (predictors, rungs, barriers, align info)
results/set1_pairs.csv              per-pair flat table, SET 1
results/set4_goldfish.jsonl         per-language-pair raw records, SET 4
results/set4_pairs.csv              per-language-pair flat table, SET 4
results/rung_summary.csv            rung x substrate x metric summary
results/predictor_auroc.csv         SET 1 predictor table: held-out AUROC, permutation null, BH q
results/set4_predictors.csv         SET 4 predictor rank correlations (n=4, descriptive)
figs/set1_dfloor_by_rung.png        Δfloor by rung, per size
figs/set1_rescue_vs_predictor.png   realised rescue vs coordinate share / CKA
figs/set1_roc.png                   held-out-by-seed ROC
figs/set4_dfloor.png                Δfloor by rung, Goldfish
```""")

open("/root/compose-audit/RESULTS_COMPOSE_AUDIT.md", "w").write("\n".join(L) + "\n")

if rung_rows:
    keys = list(rung_rows[0])
    with open(f"{R}/rung_summary.csv", "w") as f:
        f.write(",".join(keys) + "\n")
        for r in rung_rows:
            f.write(",".join(str(r.get(k, "")) for k in keys) + "\n")
print("report written:", sum(len(x) for x in L), "chars")