Robust Hurwitz property of bivariate polynomials in the space of Markov parameters

A procedure is given to determine the interval within which the Markov parameters of a general polynomial, such as real and complex univariate as well as real bivariate, might be allowed to vary so that the strict Hurwitz property remains invariant. These results may be generalized to multivariable polynomials, with complex coefficients. Based on the fact that the space of Markov parameters is a convex one this method may be used to find a quick qualitative measure of the degree of stability robustness for a nominal polynomial of a general type, i.e. interval, polytopic, and multilinear, whose treatment in general is impractical in the space of polynomial coefficients, from a computational point of view