Files
geointel/backend/app/services/detection_comparison_service.py
T
JensandClaude Opus 5 c8d32a4801 serve a promoted model at the post-processing it was gated on
scripts/evaluate_belgium_building_candidate.py freezes its post-processing
before the protected test — NMS IoU and a containment threshold selected during
calibration, defaulting to 1.0. The runtime applied a hardcoded 0.85, so a
promoted candidate was served under suppression its evaluation never measured
and dropped detections the gate had counted. Neither report showed the
difference. That constant was mine, added without noticing the evaluation
pipeline already had a tuned value for the same concept.

Containment is now configuration, recorded on every run beside the duplicate
IoU threshold, so an operator can serve a candidate at the value it was gated
at and afterwards see which value produced a given score.

Two runs that post-processed differently produced different candidate sets from
the same model output, so the comparison endpoint refuses to rank them. Runs
recorded before those values were persisted carry none, and absence is not
treated as a difference.

The remaining gap is deliberate and documented rather than closed: the gate
scores the model on its protected test set, the workbench scores the whole
pipeline including coverage clipping and the tile-edge filter. A promoted
candidate will not reproduce its gate F1 exactly, and pretending otherwise
would be the worse answer.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-08-22 21:15:05 +02:00

201 lines
8.8 KiB
Python

"""Placing two detection runs side by side, honestly.
The workbench ranks model variants by a stored F1, each measured at that
variant's own confidence threshold. That number says as much about the
threshold as about the model: a conservatively calibrated detector looks worse
than a liberal one without detecting anything differently. Average precision
describes the whole ranking the model produced and is the comparable figure.
Comparability comes first, though. Two runs over different rasters, scored
against different references, or covering different ground are not two answers
to one question, and no metric makes them so.
"""
from __future__ import annotations
from typing import Any
from app.core.errors import AppError
class DetectionComparisonService:
# A run whose inference footprint was never established cannot be placed
# beside one that was: their recalls have different denominators.
PROVEN_COVERAGE_MODES = ("persisted_tile_manifest_union",)
@staticmethod
def assess_comparability(entries: list[dict[str, Any]]) -> dict[str, Any]:
"""Say whether these runs answer the same question, and why not if they don't."""
if len(entries) < 2:
raise AppError(
code="DETECTION_COMPARISON_NEEDS_TWO_RUNS",
message="Comparing detection models requires at least two runs",
status_code=400,
)
reasons: list[str] = []
source_rasters = {str(entry.get("dataset_id")) for entry in entries}
if len(source_rasters) > 1:
reasons.append("different_source_raster")
references = {str(entry.get("reference_dataset_id")) for entry in entries}
if len(references) > 1:
reasons.append("different_reference_dataset")
if any(
str(entry.get("coverage_mode")) not in DetectionComparisonService.PROVEN_COVERAGE_MODES
for entry in entries
):
reasons.append("coverage_not_proven")
populations = {int(entry.get("reference_evaluated_count") or 0) for entry in entries}
if len(populations) > 1:
reasons.append("different_evaluated_population")
# Two runs that suppressed duplicates differently produced different
# candidate sets from the same model output, so their scores describe
# different pipelines. Runs from before these values were recorded
# carry none; absence is not a difference.
post_processing = {
(
entry.get("containment_suppression_threshold"),
entry.get("duplicate_iou_threshold"),
)
for entry in entries
}
if len(post_processing) > 1:
reasons.append("different_post_processing")
return {
"comparable": not reasons,
"blocking_reasons": reasons,
"source_raster_count": len(source_rasters),
"reference_dataset_count": len(references),
"evaluated_population_counts": sorted(populations),
}
@staticmethod
def rank(rows: list[dict[str, Any]]) -> list[dict[str, Any]]:
"""Order runs by average precision, stating the margin and any tie.
Ranking on the F1 each run happened to be read at would order the
thresholds, not the models.
"""
ordered = sorted(
rows,
key=lambda row: (-(row.get("average_precision") or 0.0), str(row.get("model_asset_id") or "")),
)
if not ordered:
return []
leader = ordered[0].get("average_precision") or 0.0
tied_count = sum(1 for row in ordered if (row.get("average_precision") or 0.0) == leader)
runner_up = (ordered[1].get("average_precision") or 0.0) if len(ordered) > 1 else leader
ranked: list[dict[str, Any]] = []
for row in ordered:
average_precision = row.get("average_precision") or 0.0
is_leader = average_precision == leader
ranked.append(
{
**row,
"rank": 1 if is_leader else 1 + sum(
1 for other in ordered if (other.get("average_precision") or 0.0) > average_precision
),
# Distance behind the best run; zero for the leader itself.
"average_precision_gap": leader - average_precision,
"tied": is_leader and tied_count > 1,
# Only the leader has a lead; stating it on every row would
# invite reading a follower's gap as an advantage.
"lead_over_next": (leader - runner_up) if is_leader and tied_count == 1 else None,
}
)
return ranked
@staticmethod
def compare_runs(
db,
*,
analysis_run_ids: list,
reference_dataset_id,
iou_threshold: float = 0.5,
) -> dict[str, Any]:
"""Score several runs against one reference and rank them on AP.
Each run is scored through the same QA path the workbench uses, so the
comparison and the persisted quality checks cannot drift apart.
"""
# Lazy: detection_service imports this module's siblings at load.
from app.models import AnalysisRun
from app.services.detection_service import DetectionService
if len(set(analysis_run_ids)) < 2:
raise AppError(
code="DETECTION_COMPARISON_NEEDS_TWO_RUNS",
message="Comparing detection models requires at least two distinct runs",
status_code=400,
)
entries: list[dict[str, Any]] = []
rows: list[dict[str, Any]] = []
for analysis_run_id in analysis_run_ids:
result = DetectionService.compare_detections_with_reference(
db,
analysis_run_id=analysis_run_id,
reference_dataset_id=reference_dataset_id,
iou_threshold=iou_threshold,
)
run = db.get(AnalysisRun, analysis_run_id)
parameters = (run.parameters_json if run and isinstance(run.parameters_json, dict) else {}) or {}
run_result = (run.result_json if run and isinstance(run.result_json, dict) else {}) or {}
coverage = result.get("coverage") if isinstance(result.get("coverage"), dict) else {}
curve = result.get("precision_recall_curve") or {}
entries.append(
{
"analysis_run_id": analysis_run_id,
"dataset_id": getattr(run, "dataset_id", None),
"model_id": getattr(run, "model_name", None),
"model_asset_id": parameters.get("model_asset_id"),
"reference_dataset_id": reference_dataset_id,
"coverage_mode": coverage.get("mode"),
"reference_evaluated_count": coverage.get("reference_evaluated_count"),
# Recorded on the run itself, so two runs that suppressed
# duplicates differently cannot be ranked against each other.
"containment_suppression_threshold": run_result.get("containment_suppression_threshold"),
"duplicate_iou_threshold": run_result.get("duplicate_iou_threshold"),
}
)
rows.append(
{
"analysis_run_id": str(analysis_run_id),
"quality_check_id": result.get("quality_check_id"),
"model_id": getattr(run, "model_name", None),
"model_asset_id": parameters.get("model_asset_id"),
"run_confidence_threshold": parameters.get("confidence_threshold"),
"average_precision": curve.get("average_precision"),
"best_f1": curve.get("best_f1"),
"best_f1_threshold": curve.get("best_f1_threshold"),
# The figure the workbench used to rank on, kept visible so
# the difference between the two readings is auditable.
"f1_at_run_threshold": result.get("f1_score"),
"precision_at_run_threshold": result.get("precision"),
"recall_at_run_threshold": result.get("recall"),
"containment_suppression_threshold": run_result.get("containment_suppression_threshold"),
"duplicate_iou_threshold": run_result.get("duplicate_iou_threshold"),
}
)
comparability = DetectionComparisonService.assess_comparability(entries)
return {
"reference_dataset_id": str(reference_dataset_id),
"iou_threshold": iou_threshold,
"comparability": comparability,
"ranking_metric": "average_precision",
"rows": DetectionComparisonService.rank(rows),
}