ThmDex – An index of mathematical definitions, results, and conjectures.
Result R4814 on D3348: Markov chain
Markov chain triple iff reverse is a Markov chain triple
Formulation 0
Let $X$, $Y$, and $Z$ each be a D202: Random variable.
Then the following statements are equivalent
(1) $X \to Y \to Z$ is a D3348: Markov chain
(2) $Z \to Y \to X$ is a D3348: Markov chain
Proofs
Proof 0
Let $X$, $Y$, and $Z$ each be a D202: Random variable.
Follows from the characterisation result R4811: Markov chain triple iff endpoints conditionally independent since the conditional independence relation is symmetric. $\square$