pythonoptunamlhyperparameterafter-work
Optuna 5.0 after work: default sampler → Multivariate TPE
Optuna 5.0.0: single-obj default → Multivariate TPE (+ constant liar, enhanced bandwidth); multi-obj NSGA-II → Multi-Objective TPE; importance → PED-ANOVA. Same seed may diverge after ~trial 10. Revert: TPESampler(multivariate=False, constant_liar=False). Not investment advice.