The paper considers a continuous review (s,S) inventory system where the interarrival times of the customers and the quantities demanded by them (demand batch sizes) form two independent and identically distributed sequences. The performance of several easy-to-compute optimal policy approximations based on the asymptotic renewal theory are evaluated. The results are tabulated for a wide range of parameter settings for gamma, log-normal, truncated normal, Weibull and inverse Gaussian batch size distributions. The interarrival time distributions are assumed to be exponential. The exact policy is computed by a search routine using the numerical methods of McConalogue.
