The impact of quick response in inventory-based competition

We propose a multi-period extension of the competitive newsvendor model of Lippman and McCardle (1997) to investigate the impact of quick response under competition. For this purpose, we consider two retailers that compete in terms of inventory: customers that face a stockout at their first-choice store will look for the product at the other store. Consequently, the total demand that each retailer faces depends on the competitor's inventory level. We allow for asymmetric reordering capabilities, and we are particularly interested in the case when one of the firms has a lower ordering cost but can only produce at the beginning of the selling season, whereas the second firm has higher costs but can replenish stock in a quick response manner taking advantage of any incremental knowledge about demand (if it is available). We visualize this problem as the competition between a traditional make-to-stock retailer that builds up inventory before the season starts versus a retailer with a responsive supply chain that can react to early demand information. We provide conditions for this game to have a unique pure-strategy subgame-perfect equilibrium, which then allows us to perform numerical comparative statics. Our results confirm in a competitive setting the intuitive fact that quick response is more beneficial when demand uncertainty is higher, or exhibits a higher correlation over time. Finally, we find that part of the competitive advantage from quick response arises from the asymmetry in response capabilities.