AISM 52, 778-789
(Received May 18, 1998; revised August 6, 1999)
Abstract. Let $F_0$ be the event that $l_0$ $0$-runs of length $k_0$ occur and $F_1$ be the event that $l_1$ $1$-runs of length $k_1$ occur in a two-state Markov chain. In this paper using a combinatorial method and the Markov chain imbedding method, we obtained explicit formulas of the probability generating functions of the sooner and later waiting time between $F_0$ and $F_1$ by the non-overlapping, overlapping and "greater than or equal" enumeration scheme. These formulas are convenient for evaluating the distributions of the sooner and later waiting time problems.
Key words and phrases: Waiting time problems, discrete distributions of order $k$, Markov chain, Markov chain imbedding method, probability generating function.