MTH302 Applied Probability - CourseWork
Hello, dear friend, you can consult us at any time if you have any questions, add WeChat: daixieit
MTH302 Applied Probability - CourseWork
1. (2 points) Let F and G be probability generating functions. Show that FG is also a probability generating function.
2. (2 points) For a simple random walk S with S0 = 0 and 0 < p = 1 − q < 1, show that the maximum M = max{Sn : n ≥ 0} satisfies P(M ≥ k) = [P(M ≥ 1)]k for k ≥ 0.
3. (2 points) Let Zn be the size of the nth generation in a GW process with Z0 = 1, E(Z1 ) = µ . Show that
E(Zn Zm ) = µn −mE(Zm(2)) for m ≤ n.
4. (3 points) Let {Sn : n ≥ 0} be a simple random walk with S0 = 0, and let Mn = max{Sk : 0 ≤ k ≤ n}. Show that Yn = Mn −Sn defines a Markov chain; find the transition probabilities of this chain.
5. (3 points) Last exits. Let
lij (n) = P(Xn = j,Xk i for 1 ≤ k < n|X0 = i),
the probability that the chain passes from i to j in n steps without revisiting i. Writing
∞
Lij (s) =X sn lij (n),
n=1
show that Pij (s) = Pii (s)Lij (s) if i j .
6. (3 points) Let X be a Markov chain containing an absorbing state s with which all other states i communicate, in the sense that pis (n) > 0 for some n = n(i). Show that all states other than s are transient.
2022-05-31