No abstract

No abstract

No abstract

compound symmetry, Cronbach's alpha, internal consistency, test reliability,

Two transformation matrices are introduced, L and D, which contain zero and unit elements only. If A is an arbitrary (n, n) matrix, L eliminates from vecA the supradiagonal elements of A, while D performs the inverse transformation for symmetric A. Many properties of L and D are derived, in particular in relation to Kronecker products. The usefulness of the two matrices is demonstrated in three areas of mathematical statistics and matrix algebra: maximum likelihood estimation of the multivariate normal distribution, the evaluation of Jacobians of transformations with symmetric or lower triangular matrix arguments, and the solution of matrix equations.