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Optimize tabular models with cross-validation, grid and random search, Bayesian and multi-fidelity optimization, and Optuna for reliable, efficient tuning.
Implement k-means, PCA, UMAP, DBSCAN/HDBSCAN and Louvain clustering from scratch and with scikit-learn, then apply them to single-cell RNA, geospatial and mixed-type data.
Forecast single and multiple time series with linear regression, random forests and xgboost: engineer lag and window features, apply recursive and direct multistep strategies, and backtest with error metrics.
Create lag, window, trend and seasonality features from time series — Fourier terms, calendar holidays, encodings — then forecast with regression models using direct and recursive strategies.
Transform raw data into model-ready features by imputing missing values, encoding categorical variables, discretizing, scaling, and assembling pipelines with pandas, scikit-learn, and Feature-engine.
Select the best features in a dataset using filter, wrapper, embedded and hybrid methods: correlation, chi-square, ANOVA, Lasso, tree importance and recursive elimination.
Interpret linear regression, decision trees, random forests, and black-box models in Python using LIME, SHAP, partial dependence, ALE plots, and permutation feature importance.
Improve classifiers trained on imbalanced data: apply under-sampling, SMOTE and other over-sampling methods, cost-sensitive learning, ensembles, and metrics like ROC-AUC and balanced accuracy.
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