A SAS® Macro for the Generalized RAS Algorithm

The problem of constraining matrices of mixed sign to controls of possibly mixed sign arises in input-output matrices in economics and net migration in demography. The recently developed Generalized RAS (GRAS) algorithm is presented to solve these problems. The GRAS algorithm produces a unique solution that minimizes an entropy-like function. The algorithm is applied to a well-known example and compared to the solution originally obtained using a generalization of the Akers-Siegel procedure.