A covariance matrix is a square matrix whose entries represent pairwise covariances among variables. In principal component analysis, it captures relationships between features so PCA can reduce redundancy by minimizing covariance between feature pairs while maximizing feature variance. section 3.5
Feature relationships in house-price data
A PCA workflow can analyze variables such as area, bedrooms, distance, and schools, then create new variables as combinations of the original features. section 3.5




