Abstract: In this paper, an inventory management with selling by Internet auctions and purchasing by reverse auctions is studied in the context of e-commerce. The considered inventory management has the following two characteristics. One is that the retailer sells products by Internet auctions, another one is that the retailer makes procurement management by reverse auctions. For the single-period case, it is shown that the retailer's expected revenue is a strictly increasing and concave function of the purchased quantity under Internet auctions, leading to the retailer's optimal procurement strategy and the suppliers' optimal bidding strategy. For the multi-period case, the optimal control model is first constructed for the retailer by using Markov decision processes. Then, the retailer's optimal procurement strategy is obtained and the suppliers' Bayesian-Nash equilibrium bidding strategies are similar to the base-stock policy. These results not only show the effect of auction mechanism on optimal procurement strategy for the retailer, but also provide an important reference for managers to manage inventory under selling by Internet auctions and purchasing by reverse auctions.

Key words: inventory management, Internet auction, reverse auction, Markov decision processes