Commit Graph

2 Commits

Author SHA1 Message Date
ramseshk 11182b47f8 Fix ML calibration: logistic regression + Platt/isotonic + realistic NWP errors
Calibration overhaul:
- Logistic regression mode for synthetic/bootstrap data (prevents LightGBM overfit)
- 3-layer calibration stack: raw LR → Platt scaling → isotonic regression
- Extreme probability smoothing: blend toward 0.5 when raw>0.95 or raw<0.05
- Platt preferred over isotonic (isotonic produces step functions with few points)
- Continuous precipitation probability in bootstrap (beta distribution, not just 0/100)
- Realistic NWP forecast errors: temp σ=2.0°C, rain calibration bias, diurnal-aware noise
- Outlier injection: 10% of days have 2-3x larger errors (typhoon/low-pressure days)
- LR model + StandardScaler saved as _lr.pkl alongside .lgb marker

Results:
- temp_gt_30c: AUC=0.987, Brier=0.049, predictions vary 20-85% per day
- rain_gt_0mm: AUC=0.979, Brier=0.042, predictions vary 15-85% per day
- temp_gt_35c: AUC=0.713 (realistic — extreme heat is hard to predict)
2026-08-11 10:50:05 +08:00
ramseshk 7d7a67bd20 Add ML prediction pipeline — LightGBM, calibration fix, ensemble disagreement
Tier 1 ML enhancements:
- Feature engineering (37 features across 5 groups: thermal, dynamic,
  moisture, temporal, interaction) from NWP model output
- 7 LightGBM probability models for rain/temp/wind thresholds
- Temperature-scaled probabilities to prevent overconfidence on bootstrap data
- MLPredictor: unified inference pipeline replacing heuristic sigmoids
- Ensemble disagreement signals (composite spread → edge amplification)
- Fixed calibration loop: update_calibration() now functional (EMA of errors)
- record_outcome() wired for post-resolution feedback
- Nautilus strategy updated: ML predictions take priority, heuristics as fallback
- Historical backtest engine with Sharpe/ROI/max-DD simulation
- Bootstrap training data generator from HK climate normals

Run: python ml/train.py && python ml/backtest.py --edge 50
2026-08-10 17:50:07 +08:00