Code / experiments/micro/expA_probe_reliability/implementation/benchmark.py
experiments/micro/expA_probe_reliability/implementation/benchmark.py
185 lines
#!/usr/bin/env python3
# =============================================================================
# Project : modelmap
# File : experiments/micro/expA_probe_reliability/implementation/benchmark.py
# Purpose : expA run #1 — probe noise floor on a real 4-bit model + nulls
# Author : Simon-Pierre Boucher
# Contact : contact@spboucher.ai
# Website : https://modelmap.io
# Created : 2026-08-12
# Modified : 2026-08-12
# Platform : macOS / Apple Silicon (arm64) — MLX / Metal
# License : All rights reserved (research code)
# =============================================================================
"""expA run #1 (hypothesis registered in hypothesis.md before this run).
Per-layer linear probes with the full controls doctrine on Qwen3-0.6B-4bit:
3 properties x 2 disjoint promptsets x 28 layers x 5 seeds, shuffled-label
controls built into every probe, random-init architecture twin as the
structure-from-architecture null, bootstrap p-values + BH-FDR across layer
scans, replication rate on top-k layer sets.
"""
from __future__ import annotations
import json
import subprocess
import sys
import time
from pathlib import Path
import numpy as np
ROOT = Path(__file__).resolve().parents[4]
sys.path.insert(0, str(ROOT / "src"))
sys.path.insert(0, str(ROOT / "benchmarks"))
from hardware_manifest import manifest
from modelmap.capture.mlx_capture import capture_mean_pooled, install_taps, random_init_twin
from modelmap.probes.linear import probe_with_control
from modelmap.stats.replication import bh_fdr, bootstrap_ci, replication_rate
MODEL = "mlx-community/Qwen3-0.6B-4bit"
PROPERTIES = ("lang_id", "code_prose", "arith")
SETS = ("A", "B")
SEEDS = (0, 1, 2, 3, 4)
TOP_K = 5
FDR_Q = 0.05
PROMPTS = ROOT / "benchmarks" / "promptsets"
def load_set(name: str) -> tuple[list[str], np.ndarray]:
items = [json.loads(l) for l in (PROMPTS / f"{name}.jsonl").read_text().splitlines()]
return [it["text"] for it in items], np.array([it["label"] for it in items])
def probe_grid(reps: np.ndarray, labels: np.ndarray) -> list[dict]:
"""All (layer, seed) probe cells for one representation tensor."""
out = []
n_layers = reps.shape[1]
for layer in range(n_layers):
for seed in SEEDS:
r = probe_with_control(reps[:, layer, :], labels, seed=seed)
out.append({"layer": layer, "seed": seed,
"task_acc": r.task_accuracy,
"control_acc": r.control_accuracy,
"selectivity": r.selectivity})
return out
def summarize(cells: list[dict], n_layers: int) -> dict:
"""Per-layer aggregation: means, seed SD, bootstrap CI + p on selectivity."""
rng = np.random.default_rng(0)
layers = []
pvals = []
for layer in range(n_layers):
sel = np.array([c["selectivity"] for c in cells if c["layer"] == layer])
acc = np.array([c["task_acc"] for c in cells if c["layer"] == layer])
point, lo, hi = bootstrap_ci(sel, rng=rng)
boots = rng.choice(sel, size=(10_000, sel.size)).mean(axis=1)
p = float(max((boots <= 0).mean(), 1 / 10_000))
pvals.append(p)
layers.append({"layer": layer,
"task_acc_mean": float(acc.mean()),
"task_acc_seed_sd": float(acc.std(ddof=1)),
"selectivity_mean": point,
"selectivity_ci": [lo, hi],
"p_boot": p})
disc = bh_fdr(np.array(pvals), q=FDR_Q)
for row, d in zip(layers, disc):
row["fdr_significant"] = bool(d)
top_sets = []
for seed in SEEDS:
acc_by_layer = [(c["layer"], c["task_acc"]) for c in cells if c["seed"] == seed]
top = {l for l, _ in sorted(acc_by_layer, key=lambda t: -t[1])[:TOP_K]}
top_sets.append(top)
rep_point, rep_lo, rep_hi = replication_rate(top_sets)
return {"layers": layers,
"replication_rate_topk": {"k": TOP_K, "point": rep_point, "ci": [rep_lo, rep_hi]},
"n_fdr_significant": int(disc.sum())}
def main() -> int:
import mlx.core as mx
from mlx_lm import load
from mlx_lm.utils import hf_repo_to_path
t_start = time.time()
mx.random.seed(0)
model, tokenizer = load(MODEL)
taps = install_taps(model)
model_path = hf_repo_to_path(MODEL)
twin = random_init_twin(model_path)
twin_taps = install_taps(twin)
results = {"real": {}, "twin": {}}
grids = {"real": {}, "twin": {}}
for prop in PROPERTIES:
for s in SETS:
name = f"{prop}_{s}"
texts, labels = load_set(name)
toks = [tokenizer.encode(t) for t in texts]
print(f"capture real {name} ({len(texts)} prompts)…", flush=True)
reps = capture_mean_pooled(model, taps, toks)
grids["real"][name] = (probe_grid(reps, labels), reps.shape[1])
if s == "A": # architecture null on the A sets
print(f"capture twin {name}…", flush=True)
reps_t = capture_mean_pooled(twin, twin_taps, toks)
grids["twin"][name] = (probe_grid(reps_t, labels), reps_t.shape[1])
for kind in ("real", "twin"):
for name, (cells, n_layers) in grids[kind].items():
results[kind][name] = summarize(cells, n_layers)
results[kind][name]["cells"] = cells
# -------- headline numbers
summary = {}
for prop in PROPERTIES:
a = results["real"][f"{prop}_A"]["layers"]
b = results["real"][f"{prop}_B"]["layers"]
seed_sd = float(np.mean([r["task_acc_seed_sd"] for r in a + b]))
shifts = [abs(ra["task_acc_mean"] - rb["task_acc_mean"]) for ra, rb in zip(a, b)]
n_shift = int(sum(s > max(seed_sd, 1e-9) for s in shifts))
twin_sel = float(max(r["selectivity_mean"] for r in results["twin"][f"{prop}_A"]["layers"]))
summary[prop] = {
"mean_seed_sd": seed_sd,
"mean_dataset_shift": float(np.mean(shifts)),
"layers_shift_gt_seed_sd": n_shift,
"n_layers": len(a),
"max_task_acc_A": float(max(r["task_acc_mean"] for r in a)),
"max_task_acc_B": float(max(r["task_acc_mean"] for r in b)),
"twin_max_selectivity": twin_sel,
"replication_topk_A": results["real"][f"{prop}_A"]["replication_rate_topk"]["point"],
"replication_topk_B": results["real"][f"{prop}_B"]["replication_rate_topk"]["point"],
}
print(f"{prop:12s} seedSD={seed_sd:.4f} shift={summary[prop]['mean_dataset_shift']:.4f} "
f"layers(shift>sd)={n_shift}/{len(a)} maxAccA={summary[prop]['max_task_acc_A']:.3f} "
f"twinMaxSel={twin_sel:.3f} repl={summary[prop]['replication_topk_A']:.2f}")
commit = subprocess.run(["git", "rev-parse", "HEAD"], cwd=ROOT,
capture_output=True, text=True, check=False).stdout.strip()
ts = time.strftime("%Y%m%dT%H%M%SZ", time.gmtime())
outdir = ROOT / "results" / "expA_probe_reliability" / ts
outdir.mkdir(parents=True)
doc = {
"experiment": "expA_probe_reliability",
"run": 1,
"scope": "probe noise floor, 3 properties x 2 sets x 28 layers x 5 seeds + twin null",
"commit": commit,
"config": {"model": MODEL, "seeds": list(SEEDS), "top_k": TOP_K, "fdr_q": FDR_Q,
"promptsets": json.loads((PROMPTS / "manifest.json").read_text())},
"manifest": manifest(),
"summary": summary,
"results": results,
"wall_seconds": round(time.time() - t_start, 1),
}
(outdir / "results.json").write_text(json.dumps(doc, indent=2) + "\n")
print(f"results -> {outdir / 'results.json'} ({doc['wall_seconds']} s)")
return 0
if __name__ == "__main__":
sys.exit(main())