Glossary: Unsupervised Learning
PCA (principal component analysis)
Also written: PCA, principal component analysis
A method that finds the directions along which the data spreads most and describes each row by its coordinates (scores) along them. It draws a 2D map or compresses many columns into a few, and needs scaled data.
Where the book teaches it
Related terms
principal componentloadingsexplained variance ratioreconstruction error