We consider carrier collaboration in less-than-truck load transportation, where multiple carriers exchange their pickup and delivery requests with service time windows in order to improve their operational efficiency by increasing vehicle fill rates and reducing empty vehicle repositions. Because of the autonomy and confidentiality requirements of these carriers, combinatorial auctions are usually used for collaborative transportation planning among them. However, single-round combinatorial auctions proposed in the literature suffer from the difficulty of determining which bundles of requests to bid for, whereas iterative combinatorial auctions based on linear prices suffer from the difficulty of reaching market-clearing prices, which may lead to an inefficient request allocation. Moreover, combinatorial auctions are not well adapted to carrier collaboration since carriers are both sellers and buyers. Motivated by the clock-proxy auction proposed by Ausubel, Cramton, and Milgrom (2006), we develop a combinatorial clock-proxy exchange for carrier collaboration. This exchange has two phases. The first chock phase is an iterative exchange designed based on Lagrangian relaxation, whereas in the second proxy phase, the bids that each carrier submits to its proxy agent are determined based on the information observed in the clock phase. The proposed approach combines the simple and transparent price discovery of the clock exchange with the efficiency of the proxy exchange. Numerical experiments on randomly generated instances demonstrate the effectiveness of the clock-proxy exchange.
Mots clés : Collaborative logistics, carrier collaboration, combinatorial exchange, combinatorial auction, collaborative transportation planning