exp-model-parameter-similarity/results/cross-layer-qkv/REPORT.md

Cross-layer QKV CPU study

Primary protocol and exploratory addendum are reported separately; no post-hoc success relabeling.

• Primary state: completed; selected candidate: [].
• Candidate counts: {'full_attention': 15, 'qkv_head': 960, 'qk_map': 30, 'qk_head': 960, 'v_group': 60}.
• Passing counts (approximate tier, all gates): {'full_attention': 0, 'qkv_head': 0, 'qk_map': 0, 'qk_head': 0, 'v_group': 0}.
• Primary computation seconds: 74.78326310915872; peak RSS KiB: 172056.

What was measured

Six full-attention layers, indices 3/7/11/15/19/23; all 15 cross-layer pairs. No within-layer Q/K/V interchange. Same normalized hidden inputs from both source layers; frozen Q/K norm, partial RoPE, GQA, V, output gate and O. QK head probabilities, whole-map injection in original/frozen matched head order, direct V functions, complete head contributions in residual coordinates, and complete branches were separated. Primary metrics use queries 7–31. Discrete matching uses calibration only; no continuous alignment, scale fitting or training. No primary candidate passed, so primary validation/fresh/network intervention stages were not entered.

• full_attention: n=15, best worst output error=1.8534952718777882, minimum worst-text mean JS=None, best worst direct V error=None.
• qkv_head: n=960, best worst output error=1.3442678606109162, minimum worst-text mean JS=0.08609102699674716, best worst direct V error=None.
• qk_map: n=30, best worst output error=0.7028184861876081, minimum worst-text mean JS=0.1696159433927246, best worst direct V error=None.
• qk_head: n=960, best worst output error=None, minimum worst-text mean JS=0.08609102699674716, best worst direct V error=None.
• v_group: n=60, best worst output error=None, minimum worst-text mean JS=None, best worst direct V error=1.503141145681371.

Exploratory metric audit: frozen one-source candidate

After inspecting primary calibration results, one candidate was frozen: layer3 head7 vs layer23 head6 on H23. This addendum audited the instability of unweighted top-k tail ranking; original primary results were not changed. Four old validation and four previously unused fresh texts were evaluated with frozen extra gates and no candidate fallback.

• Addendum fresh function pass: False.
• Overall addendum state: completed; primary unchanged/negative: True. Fresh probability-mass and fixed V/gate/O readout measurements show conditional behavioral overlap; strict fresh mean-JS, row-JS-P95 and row-TV-P95 limits still failed. No full-network substitution was run after that failure. V similarity, bidirectionality and complete QKV-head equivalence are not established. The actual-H3 cache probability is a separate different-input diagnostic, not the same-input function comparison.

Limits and retention

This is a short text-only pilot, not proof of absence of repetition elsewhere. Exact arithmetic, matrix coordinates, retrieval behavior and final residual output are distinct questions. Centered value Gram CKA can be high even for independent Gaussian projections of common inputs; it is not substitution evidence. All weights and large profile caches remain on the authorized server. Git delivery includes all plot tables, probabilities, protocols and cache location/hash metadata. No GPU, new checkpoint download, model training, continuous R fitting or automatic weight/cache deletion.