Recurrence and transience of near-critical multivariate growth models: criteria and examples

Abstract: We discuss complementary recurrence and transience criteria for stochastic processes $(X_n){n \ge 0}$ with values in the $d$-dimensional orthant $\mathbb R^d+$ fulfilling a non-linear stochastic equation of the form $X_{n+1}=MX_n+g(X_n)+ \xi_n$ with a primitive matrix $M$ and random noise $\xi_n$ and obeying a weak Markov property. As examples we discuss bisexual Galton-Watson processes and multivariate Galton-Watson processes, which both may be population size dependent.