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Library/ Machine Learning (Supervised + Unsupervised)/ Supervised Learning by Building/ S02 · Build: An Evaluation Harness (used for every model)

subtopic

Cross-validation done right

10 min applied10 min research2 curated resources

Compare KFold, StratifiedKFold, RepeatedStratifiedKFold and TimeSeriesSplit; use cross_validate with several metrics. Concepts: CV strategies; variance of estimates; time-aware CV; group CV Project A: RepeatedStratifiedKFold(5×3): mean ± std of recall and ROC-AUC. Project B: TimeSeriesSplit(5) with a 24-hour gap so lag features cannot leak.

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Cross-validation done right · 1x1labs.ai