3.4 The infinite-horizon case 50
3.4.1 A martingale interpretation of the finite-horizon results 51
3.4.2 The infinite-horizon case for bounded reward 52
3.4.3 The general infinite-horizon case 55
3.4.4 The infinite-horizon case with Markov rewards 59
3.5 Markov optimal stopping in continuous time 60
3.6 Appendix: a proof of Lemma 3.8 61
4 Sequential detection 65
4.1 Introduction 65
4.2 Optimal detection 65
4.3 Performance analysis 74
4.4 The continuous-time case 81
4.4.1 The Brownian case 81
4.4.2 The Brownian case – an alternative proof 86
4.4.3 An interesting extension of Wald–Wolfowitz 90
4.4.4 The case of Itˆo processes 91
4.4.5 The Poisson case 93
4.4.6 The compound Poisson case 100
4.5 Discussion 101
5 Bayesian quickest detection 102
5.1 Introduction 102
5.2 Shiryaev’s problem 103
5.3 The continuous-time case 109
5.3.1 Brownian observations 109
5.3.2 Poisson observations 115
5.4 A probability maximizing approach 122
5.5 Other penalty functions 124
5.6 A game theoretic formulation 125
5.7 Discussion 128
6 Non-Bayesian quickest detection 130
6.1 Introduction 130
6.2 Lorden’s problem 130
6.3 Performance of Page’s test 142
6.4 The continuous-time case 144
6.4.1 Brownian observations 144
6.4.2 Itˆo processes 150
6.4.3 Brownian motion with an unknown drift parameter 152
6.4.4 Poisson observations 154