Validation of Inventory models for Single-echelon Supply Chain using Discrete-event Simulation

Abstract: Inventory decision frameworks proposed in the literature for single-echelon supply chain systems rely on assumptions to obtain closed form expressions. In particular, two such frameworks - one conventional and the other with a demand undershoot - determine optimal reorder point for a desired $\beta$ or Type-II service level. In this work we assess the accuracy and applicability of these frameworks with the help of a discrete event simulation framework developed in SimPy. While in several cases the closed form literature models under-predict the service level, and thus result in a higher reorder point and safety stock, we observe some situations where model predicted service levels match the simulated results with statistical significance.