Kaynak dağıtımı kararlarının kapasite kısıtlı çok modelli Markov karar süreçleri ile modellenmesi ve eniyilenmesi

This thesis proposes a new formulation for the dynamic resource allocation problem, which converts the traditional MDP model with known parameters and no capacity constraints to a new model with uncertain parameters and a resource capacity constraint. Our motivating example comes from a medical resource allocation problem: patients with multiple chronic diseases can have either regular or special care, where the capacity of special care is limited due to financial or human resources. In such systems, it is difficult, if not impossible, to generate good estimates for the disease evolution for each patient. We formulate the problem as a two-stage stochastic integer program. However, it becomes easily intractable in larger instances of the problem for which we propose and test a parallel approximate dynamic programming algorithm. We show that commercial solvers are not capable of solving the problem instances with a large number of scenarios. Nevertheless, the proposed algorithm provides a solution in seconds even for very large problem instances. In our computational experiments, it finds the optimal solution for 42.86% of the instances. On aggregate, it achieves 0.073% mean gap value. Finally, we estimate the value of our contribution for different realizations of the parameters. Our findings show that there is a significant amount of additional utility contributed by our model.