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Linear AlgebraHardMarkov Chains & Long-Run Behavior

Markov Chains & Long-Run Behavior · Hard problem

Each day, independently, a two-state chain follows rule M1=(0.90.20.10.8)M_1 = \begin{pmatrix} 0.9 & 0.2 \\ 0.1 & 0.8 \end{pmatrix} with probability 1/21/2 or rule M2=(0.40.70.60.3)M_2 = \begin{pmatrix} 0.4 & 0.7 \\ 0.6 & 0.3 \end{pmatrix} with probability 1/21/2 (each MijM_{ij} is the probability of moving to state ii from state jj). The EFFECTIVE one-step matrix is the average Mˉ=12M1+12M2\bar M = \tfrac12 M_1 + \tfrac12 M_2. What is the steady-state probability of state 11 under Mˉ\bar M? Express your answer as a common fraction.