unsupervised learning using scikit-learn dimensionality reduction the motivation for dimensionality reduction the mnist digits database dimensionality reduction algorithms linear projection vs manifold learning principal component analysis pcathe concept pca in practice incremental pca sparse pca kernel pca singular value decomposition random projection gaussian random projection sparse random projection isomap multidimensional scaling locally linear embedding -distributed stochastic neighbor embedding other dimensionality reduction methods dictionary learning independent component analysis conclusion anomaly detection credit card fraud detection prepare the data define anomaly score function define evaluation metrics define plotting function normal pca anomaly detection pca components equal number of original dimensions search for the optimal number of principal components sparse pca anomaly detection kernel pca anomaly detection gaussian random projection anomaly detection sparse random projection anomaly detection nonlinear anomaly detection dictionary learning anomaly detection ica anomaly detection table of contents