Determinant and inverse of a sum of matrices with applications in economics and statistics

Abstract

In this note we present some useful tools concerning the determinant and the inverse of the sum of two matrices. Some of the results shown here are found in the statistical and econometric literature, but often without proof and without a clear statement of the conditions under which they hold. Some other results, however, are believed to be original. A number of applications in the fields of economics and statistics are given