Guard DEB bucket calibration

tests/test_deb_evaluation_upgrade.py

@@ -5,11 +5,13 @@ from pathlib import Path
 
 from src.analysis.deb_evaluation import (
     DEB_BUCKET_CALIBRATED_VERSION,
+    DEB_GUARDED_CALIBRATED_VERSION,
     DEB_RAW_VERSION,
     DEB_RECENT_BIAS_CORRECTED_VERSION,
     backtest_deb_versions,
     build_bucket_calibrated_corrector,
     build_recent_bias_corrector,
+    choose_guarded_deb_correction,
     evaluate_prediction_records,
     write_backtest_report,
 )
@@ -69,6 +71,58 @@ def test_bucket_calibrated_corrector_optimizes_settlement_bucket_hits():
     assert corrected["samples"] == 5
 
 
+def test_guarded_deb_correction_rejects_bucket_when_recent_holdout_gets_worse():
+    history = [
+        {"city": "ankara", "target_date": "2026-05-20", "deb_prediction": 20.49, "actual_high": 20.51},
+        {"city": "ankara", "target_date": "2026-05-21", "deb_prediction": 20.49, "actual_high": 20.51},
+        {"city": "ankara", "target_date": "2026-05-22", "deb_prediction": 20.49, "actual_high": 20.51},
+        {"city": "ankara", "target_date": "2026-05-23", "deb_prediction": 20.49, "actual_high": 20.51},
+        {"city": "ankara", "target_date": "2026-05-24", "deb_prediction": 20.49, "actual_high": 20.51},
+        {"city": "ankara", "target_date": "2026-05-25", "deb_prediction": 20.49, "actual_high": 20.49},
+        {"city": "ankara", "target_date": "2026-05-26", "deb_prediction": 20.49, "actual_high": 20.49},
+        {"city": "ankara", "target_date": "2026-05-27", "deb_prediction": 20.49, "actual_high": 20.49},
+    ]
+
+    corrected = choose_guarded_deb_correction(
+        history,
+        "ankara",
+        raw_prediction=20.49,
+        min_samples=3,
+        validation_samples=3,
+    )
+
+    assert corrected["version"] == DEB_GUARDED_CALIBRATED_VERSION
+    assert corrected["selected_version"] == DEB_RECENT_BIAS_CORRECTED_VERSION
+    assert corrected["corrected_prediction"] == 20.5
+    assert corrected["guard_reason"] == "bucket_rejected_holdout"
+
+
+def test_guarded_deb_correction_accepts_bucket_when_holdout_improves():
+    history = [
+        {"city": "ankara", "target_date": "2026-05-20", "deb_prediction": 20.49, "actual_high": 20.51},
+        {"city": "ankara", "target_date": "2026-05-21", "deb_prediction": 20.49, "actual_high": 20.51},
+        {"city": "ankara", "target_date": "2026-05-22", "deb_prediction": 20.49, "actual_high": 20.51},
+        {"city": "ankara", "target_date": "2026-05-23", "deb_prediction": 20.49, "actual_high": 20.51},
+        {"city": "ankara", "target_date": "2026-05-24", "deb_prediction": 20.49, "actual_high": 20.51},
+        {"city": "ankara", "target_date": "2026-05-25", "deb_prediction": 20.49, "actual_high": 20.51},
+        {"city": "ankara", "target_date": "2026-05-26", "deb_prediction": 20.49, "actual_high": 20.51},
+        {"city": "ankara", "target_date": "2026-05-27", "deb_prediction": 20.49, "actual_high": 20.51},
+    ]
+
+    corrected = choose_guarded_deb_correction(
+        history,
+        "ankara",
+        raw_prediction=20.49,
+        min_samples=3,
+        validation_samples=3,
+    )
+
+    assert corrected["version"] == DEB_GUARDED_CALIBRATED_VERSION
+    assert corrected["selected_version"] == DEB_BUCKET_CALIBRATED_VERSION
+    assert corrected["corrected_prediction"] == 20.6
+    assert corrected["guard_reason"] == "bucket_selected_holdout"
+
+
 def test_backtest_deb_versions_compares_raw_and_bias_corrected_versions():
     history = [
         {"city": "ankara", "target_date": "2026-05-20", "deb_prediction": 20.0, "actual_high": 22.0},
@@ -83,6 +137,7 @@ def test_backtest_deb_versions_compares_raw_and_bias_corrected_versions():
     assert report["versions"][DEB_RAW_VERSION]["samples"] == 2
     assert report["versions"][DEB_RECENT_BIAS_CORRECTED_VERSION]["samples"] == 2
     assert report["versions"][DEB_BUCKET_CALIBRATED_VERSION]["samples"] == 0
+    assert report["versions"][DEB_GUARDED_CALIBRATED_VERSION]["samples"] == 2
     assert (
         report["versions"][DEB_RECENT_BIAS_CORRECTED_VERSION]["mae"]
         < report["versions"][DEB_RAW_VERSION]["mae"]

tests/test_deb_model_family.py

@@ -123,7 +123,9 @@ def test_calculate_deb_prediction_keeps_raw_and_adds_versioned_bias_correction(m
 
     assert result["raw_prediction"] == 24.0
     assert result["prediction"] == 25.0
-    assert result["version"] == "deb_v1_recent_bias_corrected"
+    assert result["version"] == "deb_v3_guarded_calibrated"
+    assert result["selected_version"] == "deb_v1_recent_bias_corrected"
+    assert result["guard_reason"] == "bucket_unavailable"
     assert result["bias_adjustment"] == 1.0
     assert result["bias_samples"] == 3
 
@@ -169,7 +171,9 @@ def test_calculate_deb_prediction_prefers_bucket_calibration_when_enough_samples
 
     assert result["raw_prediction"] == 25.4
     assert result["prediction"] == 26.0
-    assert result["version"] == "deb_v2_bucket_calibrated"
+    assert result["version"] == "deb_v3_guarded_calibrated"
+    assert result["selected_version"] == "deb_v2_bucket_calibrated"
+    assert result["guard_reason"] == "bucket_same_adjustment"
     assert result["bias_adjustment"] == 0.6
     assert result["bias_samples"] == 5
 

tests/test_ops_training_accuracy.py

@@ -37,6 +37,7 @@ def test_training_accuracy_payload_includes_recent_deb_summary():
     assert payload["deb_summary"]["recent_14d"]["samples"] == 5
     assert "deb_v1_raw" in payload["deb_summary"]["versions"]
     assert "deb_v2_bucket_calibrated" in payload["deb_summary"]["versions"]
+    assert "deb_v3_guarded_calibrated" in payload["deb_summary"]["versions"]
 
 
 def test_training_accuracy_payload_includes_city_deb_trust_strategy():