Green cells = good parameters
Best combinations for the chosen metric. Prefer wide green plateaus over a single bright peak — plateaus mean results are robust to small parameter changes.
Red cells = poor parameters
Avoid regions where colours shift sharply with small parameter changes. Sharp gradients signal fragile, likely overfit results.
Crosshair = your current params
Ideally sits inside a green plateau. If it's on a steep colour gradient, consider moving — small α or N changes may hurt performance significantly.
Patterns to look for
Ridge: one axis dominates. Plateau: robust zone, target this. Single peak: fragile, likely overfit.