The ability to discover equilibrium prices efficiently makes auctions an effective way to trade goods. One of the recent trends in the development of auctions is combinatorial auctions. Combinatorial auctions allow the simultaneous sale of more than one item. In the existing literature, the factor of transportation cost has not been considered in combinatorial auctions. In this paper, we formul...

Combinatorial auctions, i.e. auctions where bidders can bid on combinations of items, tend to lead to more eecient allocations than traditional auctions in multi-item auctions where the agents' valuations of the items are not additive. However, determining the winners so as to maximize revenue is NP-complete. First, existing approaches for tackling this problem are reviewed: exhaustive enu-mera...

In this paper, we study the problem of maximizing welfare in combinatorial auctions with k(> 1)duplicates of each item, where k is a fixed constant (i.e. k is not the part of the input) and bidders are submodular or subadditive. We exhibit some upper and lower approximation bounds for k-duplicates combinatorial auctions. First, we show that it is NP-hard to approximate the maximum welfare for k...

We study combinatorial auctions with bidders that exhibit an endowment effect. In most of the previous work on cognitive biases in algorithmic game theory focus was analyzing implications and mitigating their negative consequences. contrast, this paper we show how some cases can be harnessed to obtain better outcomes. Specifically, Walrasian equilibria markets. It is well known exist only limit...