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 governmentspledged to spend huge sums of money to subsidize internet networks. In this paper we reviewsome systematic flaws of present subsidy policies and outline a promising alternative. We proposethat governments...

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...

A general theoretical and empirical framework is developed for assessing the potential of a vertically integrated firm to foreclose downstream competitors. Using this framework a policymaker may also evaluate the empirical welfare effects from a vertically integrated firm raising rivals' costs....