The Combinatorial Clock Auction (CCA) has frequently been used in recent spectrum auctions. It combines a dynamic clock phase and a one-off supplementary round. The winning allocation and the corresponding prices are determined by the VCG rules. These rules should encourage truthful bidding,...

We show that the class of preferences satisfying the Gross Substitutes condition of Kelso and Crawford (1982) is strictly larger than the class of Endowed Assignment Valuations of Hatfield and Milgrom (2005), thus resolving the open question posed by the latter paper. In particular, our result...

This paper studies the possibility of implementing Pareto optimal outcomes in the combinatorial auction setting where bidders may have budget constraints. I show that when the setting involves a single good, or multiple goods but with single-minded bidders, there is a unique mechanism, called...

Many auctions involve the sale of heterogenous indivisible objects. Examples are wireless spectrum, delivery routes and airport time slots. Because of complementarities or substitution effects between the objects, bidders have preferences not just over individual items but over subsets of them....

Millions of citizens and firms lack access to high speed internet, even though governments pledged to spend huge sums of money to subsidize internet networks. In this paper we review some systematic flaws of present subsidy policies and outline a promising alternative. We propose that...

Millions of citizens and firms lack access to high speed internet, even though gov- ernments pledged to spend huge sums of money to subsidize internet networks. In this paper we review some systematic flaws of present policies and outline a promising alternative. We propose that governments...

We consider the problem of allocating multiple units of an indivisible object among agents and collecting payments. Each agent can receive multiple units of the object, and his (consumption) bundle is a pair of the units he receives and his payment. An agent's preference over bundles may be...

Many financial markets are populated by dealers, who commit to participate regularly in the market, and non-dealers, who do not commit. This market structure introduces a trade-off between competition and volatility, which we study using data on Canadian treasury auctions. We document a...