MI-BIOT zero-phase IIR SSL 訓練結果
30 位未標記預訓練,正式 10 位正常人 left/right 個人化 5-fold,三個 fine-tune seeds。
固定輸入:Fp1/Fp2/Fz/C3/C4/Pz/O1/O2;raw 2 秒窗 → reflection-padded 4th-order SOS
sosfiltfilt 1–40 Hz → 200 Hz → model-side per-channel window Z-score。不使用 ASR、ICA、EA 或 causal filter。56.54%Scratch
61.09%SSL fine-tune
+4.55 ppPaired delta
8/10Subjects improved
預訓練
20,000 CUDA updates;best checkpoint 在 18,500 steps,validation reconstruction loss=0.02173,該點 external loss=0.01734。
左右腳分類
每個模式為 10 subjects × 5 folds × 3 seeds,共 300 folds。每位先平均 folds 與 seeds,再做 subject-level paired inference。SSL 相對 Scratch 為 +4.55 pp,bootstrap 95% CI [+1.58, +7.52] pp;Wilcoxon p=0.0273。


| Subject | Scratch | SSL fine-tune | Delta |
|---|---|---|---|
| sub1 | 51.73% | 64.71% | +12.98 pp |
| sub2 | 50.07% | 57.96% | +7.88 pp |
| sub3 | 54.50% | 62.83% | +8.33 pp |
| sub9 | 51.41% | 51.74% | +0.33 pp |
| sub10 | 52.00% | 56.83% | +4.83 pp |
| sub11 | 64.50% | 63.17% | -1.33 pp |
| sub12 | 74.13% | 75.58% | +1.45 pp |
| sub13 | 67.83% | 73.33% | +5.50 pp |
| sub14 | 48.67% | 57.17% | +8.50 pp |
| sub15 | 50.58% | 47.61% | -2.98 pp |
Seed 穩定性
三個 fine-tune seed 的群組 paired delta 全部為正:
| Seed | Mean delta |
|---|---|
| 20260717 | +3.62 pp |
| 20260718 | +4.47 pp |
| 20260719 | +5.56 pp |
判斷:這次可視為正向 SSL transfer:effect 超過預先常用的 +3 pp 門檻、CI 下界高於 0、8/10 位方向一致,且 Wilcoxon 通過 0.05。不過 sub11(-1.33 pp)與 sub15(-2.98 pp)仍有負遷移,受試者總數只有 10 位,因此適合稱為「有希望且具統計支持」,不宜宣稱已普遍優於所有個人化模型。
檔案
fold_results.csv · subject_comparison.csv · seed_summary.csv · statistics.json · pretrain_history.csv