Improving models & hyperparameter tuning

The improvement playbook (follow in order — tuning is the LAST step)

Hyperparameter tuning is expensive and usually not the bottleneck. Escalate in this order, re-validating after each step:

1. Fix the data — check confusion_matrix.png and train_batch*.jpg for label noise; review the top false-negative/false-positive val images; add examples of failing classes and true-background images. Data quality beats every other lever.
2. Train longer — if val mAP was still rising at the end: more epochs, higher patience.
3. Bigger input — small objects or mAP50 ≫ mAP50-95: raise imgsz (640 → 960/1280).
4. Bigger model — underfitting (train and val both mediocre): n → s → m → l.
5. Domain-matched augmentation — aerial degrees=180 flipud=0.5, crowded scenes mixup=0.1 (plus copy_paste=0.3 for segment/OBB), color-critical classes lower hsv_h (see yolo-training's training-args.md).
6. Only now: hyperparameter tuning — worth ~0.5–2 mAP when everything above is exhausted.

Decision signals: overfitting (val drops while train improves) → more data/aug or smaller model, NOT tuning. Underfitting → bigger model/longer, NOT tuning. Label noise in the confusion matrix → nothing else matters until fixed.

Compare experiments in Platform

Keep candidates in one Platform project. Train from the New Model dialog, ask Ask AI to run and compare experiments (AutoTrain), or stream authenticated local runs by setting project=username/project-slug and a unique name. Select models together in the project charts, or use Table > Diff to compare training arguments and final metrics.