2017/07/27 by Halidias, Nikolaos
#60J10 #FOS: Mathematics #Probability (math.PR)
paper · doi:10.48550/arxiv.1707.08827
Let Xn be a discrete time Markov chain with state space S (countably infinite, in general) and initial probability distribution μ(0) = (P(X0=i1),P(X0=i2),⋯,). What is the probability of choosing in random some k ∈ ℕ with k ≤ n such that Xk = j where j ∈ S? This probability is the average (1)/(n) ∑k=1n μ(k)j where μ(k)j = P(Xk = j). In this note we will study the limit of this average without assuming that the chain is irreducible, using elementary mathematical tools. Finally, we study the limit of the average (1)/(n) ∑k=1n g(Xk) where g is a given function for a Markov chain not necessarily irreducible.