On the generalized spectral subradius

In this note we study the concepts of generalized spectral subradius and joint spectral subradius of a family of matrices. We show that both these numbers are equal and we present two different formulas for them. We also explain the relation between them and maximal Lyapunov exponent of discrete linear time varying system. Finally we show that the spectral subradius is less than one if and only if a discrete linear inclusion is stable in a certain sense.