A coalition structure-based decision method in B2B E-commerce model with multiple-items

This paper proposes a new B2B electronic commerce model by using bidding information in double auctions. In B2B electronic commerce, buyers try to purchase in multiple items at the same time, since a buyer develops something products by using purchased items. Also suppliers have an incentive of making coalitions, since buyers want to purchase in multiple items. A mechanism designer has to consider an optimal mechanism which calculates an optimal matching between buyers and suppliers. But to find an optimal matching is very hard, since a mechanism calculates all combinations between buyers and suppliers. Consequently, we propose a calculation method which has two steps, first a mechanism determines winners of buyers' side, then, determines coalitions and winners of suppliers by using the result of buyers' side. This paper also discusses the improved method with dynamical mechanism design by using the bidding information. The auction protocol trees are expressed by all possible results of auctions. The result of each auction is recorded and stored with bidding data and conditions for subsequent auctions. Advantages of this paper are that each developer can procure the components to develop a certain item and tasks are allocated to suppliers effectively. The previous result of auction data can be available to shorten the period of winner determinations.