Bipartite completely positive matrices

Abstract

A non-zero n -by- n matrix A is said to be completely positive if there exist non-negative vectors b 1 ,…, b k , such that The smallest such integer k is called the factorization index of (completely positive) A , and is denoted by ø( A ). Completely positive matrices are important in the study of block designs [ 4 ], statistics and modelling of energy demand [ 3 ].