Hidden Markov models for inventory systems with deteriorating items

In this paper, we propose to apply hidden Markov model (HMM) in modelling an inventory system for deteriorating items. Each item in the inventory has certain chance to deteriorate in a fixed period of time. We propose models for both cases of deterministic and stochastic demands. With the information provided by customers, the inventory levels in the system, which are unknown, can be estimated. Numerical examples are provided to demonstrate the effectiveness of the proposed models.