Published online by Cambridge University Press: 01 January 2025
An n-rowed correlation matrix may be thought of as an ellipsoid in n-dimensional space with its center at the origin. The principal components of the matrix are essentially the semi-axes of the ellipsoid. A direct and simple method of computing the lengths and directions of these semi-axes is presented.
For the matric terminology, notation, and theorems used in this paper, see Wedderburn's Lectures on Matrices (6), particularly Chaps. 1, 2, 3, and 6. An elegant presentation of the method of principal components, using the algebra of matrices, has been given by Householder and Young (7).