# Short form:

Win-Vector LLC’s Dr. Nina Zumel has a three part series on Principal Components Regression that we think is well worth your time.

- Part 1: the proper preparation of data (including scaling) and use of principal components analysis (particularly for supervised learning or regression).
- Part 2: the introduction of
*y*-aware scaling to direct the principal components analysis to preserve variation correlated with the outcome we are trying to predict. - Part 3: how to pick the number of components to retain for analysis.