New results on the newsvendor model and the multi-period inventory model with backordering

We analyze the newsvendor model and the multi-period inventory model, and provide some new results. For the newsvendor model, the best case newsvendor cost over all demand distributions with a given demand mean and variance is zero. In addition, under symmetric demand distributions, the newsvendor's costs remain the same when the holding and shortage costs are switched. For the multi-period inventory model with stochastic lead times, a dilation ordering of lead times implies an ordering of optimal costs.