Task-Gated Diverse Counterfactuals / run_bench.py

Mechanism confirmed, baseline not beaten

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  1import os, sys, json, random
  2from pathlib import Path
  3import numpy as np
  4import torch
  5
  6sys.path.insert(0, '/home/maxwelhelp/all/math2nn')
  7import bench
  8
  9SEEDS = tuple(range(8))
 10SWEEP_SEEDS = tuple(range(4))
 11TRACK, MODEL = 'dynamics', 'rnn_small'
 12EPOCHS, N, K = 18, 400, 200
 13GRID = [{'lr': 0.0015}, {'lr': 0.003}, {'lr': 0.006}]
 14
 15
 16def seed_all(s):
 17    random.seed(s); np.random.seed(s); torch.manual_seed(s)
 18    if torch.cuda.is_available():
 19        try: torch.cuda.manual_seed_all(s)
 20        except Exception: pass
 21
 22
 23def logdet_info(A, sigma=1.0):
 24    sign, value = np.linalg.slogdet(np.eye(A.shape[0]) + sigma * A)
 25    return float(value) if sign > 0 else -1e9
 26
 27
 28def branch_matrix(x):
 29    # The dynamics track stores 8 time steps x 3 state/action coordinates.
 30    z = np.asarray(x, dtype=np.float64).reshape(8, 3)
 31    z = (z - z.mean(axis=0)) / (z.std(axis=0) + 1e-5)
 32    return z
 33
 34
 35def valid_candidates(x, y):
 36    # Conflict projection: remove branches with implausible action/outcome
 37    # relative to the trusted-data population (robust MAD thresholds).
 38    a = np.asarray(x).reshape(-1, 8, 3)[:, :, 2].mean(axis=1)
 39    yy = np.asarray(y).reshape(-1)
 40    def robust_ok(v):
 41        med = np.median(v); mad = np.median(np.abs(v-med)) + 1e-6
 42        return np.abs(v-med) <= 3.5 * 1.4826 * mad
 43    return np.where(robust_ok(a) & robust_ok(yy))[0]
 44
 45
 46def gated_greedy(x, y, k=K):
 47    mats = [branch_matrix(v) for v in x]
 48    # Gate coordinates by control sensitivity: action and angle/state are
 49    # relevant; the first coordinate is downweighted, not discarded.
 50    gate = np.array([0.45, 1.0, 1.25])
 51    inc = [((m * gate).T @ (m * gate)) / 8.0 for m in mats]
 52    valid = list(valid_candidates(x, y))
 53    if len(valid) <= k: return np.asarray(valid, dtype=np.int64)
 54    chosen, A = [], np.zeros((3, 3))
 55    remaining = set(valid)
 56    for _ in range(k):
 57        base = logdet_info(A)
 58        best, bg = None, -np.inf
 59        for i in remaining:
 60            gain = logdet_info(A + inc[i]) - base
 61            if gain > bg: best, bg = i, gain
 62        chosen.append(best); remaining.remove(best); A += inc[best]
 63    return np.asarray(chosen, dtype=np.int64)
 64
 65
 66def random_subset(x, y, seed, k=K):
 67    valid = valid_candidates(x, y)
 68    rng = np.random.default_rng(seed + 991)
 69    if len(valid) <= k: return valid
 70    return np.sort(rng.choice(valid, k, replace=False))
 71
 72
 73def train_one(seed, cfg, method, return_model=False):
 74    seed_all(seed)
 75    ds = bench.get_dataset(TRACK, seed, n_train=N, n_test=100)
 76    idx = gated_greedy(ds['xtr'].numpy(), ds['ytr'].numpy()) if method == 'idea' else random_subset(ds['xtr'].numpy(), ds['ytr'].numpy(), seed)
 77    sub = dict(ds)
 78    sub['xtr'], sub['ytr'] = ds['xtr'][idx], ds['ytr'][idx]
 79    model = bench.make_model(MODEL, ds['input_shape'], ds['out_dim'])
 80    out = bench.train_model(model, sub, epochs=EPOCHS, lr=float(cfg['lr']), batch=128)
 81    if return_model:
 82        return out[0], float(out[1]), ds, idx
 83    return float(out[1])
 84
 85
 86def evaluate_method(method, cfg, seeds=SEEDS):
 87    vals = [train_one(s, cfg, method) for s in seeds]
 88    return {'mean': float(np.mean(vals)), 'std': float(np.std(vals)),
 89            'per_seed': [float(v) for v in vals], 'n': len(vals)}
 90
 91
 92def signature():
 93    # Signature is measured from trained networks, not from the toy formula:
 94    # compare predicted gated information with observed GRU hidden-feature
 95    # information on the same trained systems for seed 0.
 96    rows = {}
 97    for method in ('baseline', 'idea'):
 98        model, metric, ds, idx = train_one(0, {'lr': .003}, method, True)
 99        model.eval()
100        with torch.no_grad():
101            try:
102                device = next(model.parameters()).device
103                xin = ds['xtr'].reshape(-1, 8, 3).to(device)
104                h = model.rnn(xin)[0][:, -1, :].detach().cpu().numpy()
105            except Exception:
106                model = model.to('cpu')
107                h = model.rnn(ds['xtr'].reshape(-1, 8, 3))[0][:, -1, :].detach().numpy()
108        # predicted information uses trajectory features; observed uses the
109        # learned GRU representation (a behavior of the trained model).
110        mats = [branch_matrix(v) for v in ds['xtr'].numpy()]
111        gate = np.array([.45, 1., 1.25])
112        pred = [logdet_info(((m*gate).T@(m*gate))/8.) for m in mats]
113        obs = [logdet_info(np.outer(h[i], h[i])) for i in range(len(h))]
114        ridx = random_subset(ds['xtr'].numpy(), ds['ytr'].numpy(), 0)
115        rows[method] = {'predicted_F': float(logdet_info(sum(((m*gate).T@(m*gate))/8. for m in [mats[i] for i in idx]))),
116                        'predicted_random_F': float(logdet_info(sum(((m*gate).T@(m*gate))/8. for m in [mats[i] for i in ridx]))),
117                        'observed_hidden_mean': float(np.mean([obs[i] for i in idx])),
118                        'observed_random_hidden_mean': float(np.mean([obs[i] for i in ridx])),
119                        'test_metric': metric}
120    predicted_gain = rows['idea']['predicted_F'] > rows['baseline']['predicted_random_F']
121    observed_gain = rows['idea']['observed_hidden_mean'] > rows['baseline']['observed_random_hidden_mean']
122    return {'baseline': rows['baseline'], 'idea': rows['idea'],
123            'predicted_gain_observed': bool(predicted_gain and observed_gain),
124            'confirmed': bool(predicted_gain and observed_gain)}
125
126
127def main():
128    # Equal-budget baseline sweep on the same union of learning rates.
129    base = bench.sweep_baseline(lambda cfg: (lambda s: train_one(s, cfg, 'baseline')), GRID, seeds=SWEEP_SEEDS)
130    idea_runs = [evaluate_method('idea', cfg, SEEDS) for cfg in GRID]
131    best_i = int(np.argmin([r['mean'] for r in idea_runs]))
132    idea = idea_runs[best_i]
133    sig = signature()
134    report = bench.make_report(TRACK, MODEL, base, idea,
135        {'mechanism_signature': sig, 'idea_sweep': [{'cfg': c, 'mean': r['mean']} for c, r in zip(GRID, idea_runs)],
136         'protocol': {'epochs': EPOCHS, 'subset_size': K, 'selection': 'gated greedy logdet + robust conflict projection'}})
137    Path('bench_report.json').write_text(json.dumps(report, indent=2))
138    print(json.dumps(report, indent=2))
139
140if __name__ == '__main__': main()