5 An inspector has three factories, A, B, C, to check. He spends each day in one of the factories. He chooses the factory to visit on a particular day according to the following rules.
- If he is in A one day, then the next day he will never choose A but he is equally likely to choose B or C .
- If he is in B one day, then the next day he is equally likely to choose \(\mathrm { A } , \mathrm { B }\) or C .
- If he is in C one day, then the next day he will never choose A but he is equally likely to choose B or C .
- Write down the transition matrix, \(\mathbf { P }\).
- On Day 1 the inspector chooses A.
(A) Find the probability that he will choose A on Day 4.
(B) Find the probability that the factory he chooses on Day 7 is the same factory that he chose on Day 2. - Find the equilibrium probabilities and explain what they mean.
The inspector is not satisfied with the number of times he visits A so he changes the rules as follows.
Still not satisfied, the inspector changes the rules as follows.
The new transition matrix is \(\mathbf { R }\).
On Day 15 he visits C . Find the first subsequent day for which the probability that he visits B is less than 0.1.Show that in this situation there is an absorbing state, explaining what this means.
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