ELA, Volume 13, pp. 131-145, April 2005, abstract. A Parallel Algorithm For Computing The Group Inverse Via Perron Complementation Michael Neumann and Jianhong Xu A parallel algorithm is presented for computing the group inverse of a singular M-matrix of the form A = I-T, where T is a real n-by-n matrix that is irreducible and stochastic. The algorithm is constructed in the spirit of Meyer's Perron complementation approach to computing the Perron vector of an irreducible nonnegative matrix. The asymptotic number of multiplication operations that is necessary to implement the algorithm is analyzed, which shows that the algorithm saves a significant amount of computation over the direct computation of the group inverse of A.