If I have that $X_n$ is a two-state Markov chain whose transition probability matrix is:
$P = \left( \begin{smallmatrix} \alpha & 1-\alpha\\ 1-\beta & \beta \\\end{smallmatrix} \right)$
Then $Z_n=(X_{n-1},X_n)$ is a Markov chain having the four states (0,0), (0,1), (1,0) and (1,1). How would I determine the transition probability matrix? I appreciate all of the help and suggestions!
the possible transistions are those for which $Z_{n,2} = Z_{n+1, 1}$, ie $$ (0,0) \to (0, 0)\\ (0,0) \to (0, 1)\\ (1,0) \to (0, 0)\\ (1,0) \to (0, 1)\\ (0,1) \to (1, 0)\\ (0,1) \to (1, 1)\\ (1,1) \to (1, 0)\\ (1,1) \to (1, 1) $$
and for instance the transition $(0,1)\to (1,1)$ has probability $$ P(X_{n+1} = 1, X_{n} = 1 | X_{n} = 1, X_{n-1} = 0) = P(X_{n+1} = 1, X_{n} = 1 | X_{n} = 1) $$ because of the Markov property, $$ = P(X_{n+1} = 1| X_{n} = 1) = \beta $$