Three different operations research models for the same (s, S) policy

Operations Research techniques are usually presented as distinct models. Difficult as it may often be, achieving linkage between these models could reveal their interdependency and make them easier for the user to understand. In this article three different models, namely Markov Chain, Dynamic Programming, and Markov Sequential Decision Processes, are used to solve an inventory problem based on the periodic review system. We show how the three models converge to the same (s, S) policy and we provide a numerical example to illustrate such a convergence.