As auctions are becoming the main mechanism for selling advertisement space on the web, marketing agencies specialized in bidding in online auctions are proliferating. We analyze theoretically how bidding delegation to a common marketing agency can undermine both revenues and efficiency of the...

We analyze strategic leaks due to spying out a rival’s bid in a first-price auction. Such leaks induce sequential bidding, complicated by the fact that the spy may be a counterspy who serves the interests of the spied at bidder and reports strategically distorted information. This ambiguity...

I find that current US's and EU's Antitrust laws -- in particular their "moderate" leniency programmes that only reduce or at best cancel sanctions for price-fixing firms that self-report -- may make collusion enforceable even in one-shot competitive interactions, like Bertrand oligopolies and...

A competition authority has an objective, which specifies what output profile firms need to produce as a function of production costs. These costs change over time and are only known by the firms. The objective is implementable if inequilibrium, the firms cannot collude on their reports to the...

The theoretical literature on collusion in auctions suggests that the first-price mechanism can deter the formation of bidding rings. In equilibrium, collusive negotiations are either successful or are avoided altogether, hence such analysis neglects the effects of failed collusion attempts. In...

This study explores stability in efficient collusion in government procurement auctions. In first- and second-price auctions with independent private values, we look at the possibility of vetoing collusion mechanisms and the learning of the other bidders after vetoing. The collusions in...

We consider an ad network's problem of allocating the auction for each individual impression to an optimal subset of advertisers, with the goal of revenue maximization. This is a variant of bipartite matching, except that advertisers may strategize by choosing their bidding profiles and their...

Keyword advertising, or "sponsored links" that appear alongside online search results or other online content, has grown into a multibillion-dollar market. Providers of keyword advertising, such as Google and Yahoo!, profit by auctioning keywords to advertisers. One issue of increasing...