A Three-Condition Characterization of the Moore—Penrose Generalized Inverse
Xiaomi Hu · The American Statistician · 2008
Moore—Penrose generalized inverses of matrices, defined by four conditions, are useful tools in statistical analysis. In this article a three-condition characterization of the inverses is derived. This characterization is then applied to establish a result on the Moore—Penrose generalized inverse of a matrix product.