## A two-disorder detection problem

### Volume 24 / 1997

Applicationes Mathematicae 24 (1997), 231-241
DOI: 10.4064/am-24-2-231-241

#### Abstract

Suppose that the process $X=\{X_n,n\in\N\}$ is observed sequentially. There are two random moments of time $θ_1$ and $θ_2$, independent of X, and X is a Markov process given $θ_1$ and $θ_2$. The transition probabilities of X change for the first time at time $θ_1$ and for the second time at time $θ_2$. Our objective is to find a strategy which immediately detects the distribution changes with maximal probability based on observation of X. The corresponding problem of double optimal stopping is constructed. The optimal strategy is found and the corresponding maximal probability is calculated.