Linked from
The 28 pages that link to Principal component analysis, each with the reason it gives.
EigenvalueRelated: Covariance-matrix eigenvalues quantify variance along principal components.
Linear algebraBroader topic: It uses eigenvectors of a covariance matrix to reduce data dimensions.
OrthogonalityRelated: Its component directions are orthogonal eigenvectors of the covariance matrix.
EigenvectorRelated: Its principal directions are eigenvectors of the data covariance matrix.
Eigenvalue problemRelated: Its principal directions are eigenvectors of the data covariance matrix.
Matrix theoryRelated: Its directions arise from eigenvectors or singular vectors of data matrices.
Michael E. MannRelated: The 1998 study used this method to summarize regional tree-ring networks.