Market Selection and the Information Content of Prices

We study information aggregation when n bidders choose, based on their private information, between two concurrent common‐value auctions. There are k s identical objects on sale through a uniform‐price auction in market s and there are an additional k r objects on auction in market r, which is identical to market s except for a positive reserve price. The reserve price in market r implies that information is not aggregated in this market. Moreover, if the object‐to‐bidder ratio in market s exceeds a certain cutoff, then information is not aggregated in market s either. Conversely, if the object‐to‐bidder ratio is less than this cutoff, then information is aggregated in market s as the market grows arbitrarily large. Our results demonstrate how frictions in one market can disrupt information aggregation in a linked, frictionless market because of the pattern of market selection by imperfectly informed bidders.

Market power and welfare in asymmetric divisible good auctions

We analyze a divisible good uniform‐price auction that features two groups, each with a finite number of identical bidders, who compete in demand schedules. In the linear‐quadratic‐normal framework, this paper presents conditions under which the unique equilibrium in linear demands exists and derives novel comparative statics results that highlight the interaction between payoff and information parameters with asymmetric groups. We find that the strategic complementarity in the slopes of traders' demands is reinforced by inference effects from prices, and we display the role of payoff and information asymmetries in explaining deadweight losses. Furthermore, price impact and the deadweight loss need not move together, and market integration may reduce welfare. The results are consistent with the available empirical evidence.

Mixed Mechanisms for Auctioning Ranked Items

This paper deals with the problem of designing and choosing auctioning mechanisms for multiple commonly ranked objects as, for instance, keyword auctions in search engines on Internet. We shall adopt the point of view of the auctioneer who has to select the auction mechanism to be implemented not only considering its expected revenue, but also its associated risk. In order to do this, we consider a wide parametric family of auction mechanisms which contains the generalizations of discriminatory-price auction, uniform-price auction and Vickrey auction. For completeness, we also analyze the Generalized Second Price (GSP) auction which is not in the family. The main results are: (1) all members of the family satisfy the four basic properties of fairness, no over-payment, optimality and efficiency, (2) the Bayesian Nash equilibrium and the corresponding value at risk for the auctioneer are obtained for the considered auctions, (3) the GSP and all auctions in the family provide the same expected revenue, (4) there are new interesting auction mechanisms in the family which have a lower value at risk than the GSP and the classical auctions. Therefore, a window opens to apply new auction mechanisms that can reduce the risk to be assumed by auctioneers.

Underwriting Government Debt Auctions: Auction Choice and Information Production

In this paper, we examine a novel two-stage mechanism for selling government securities, wherein the dealers underwrite in the first stage the sale of securities, which are auctioned in stage 2 via either a discriminatory auction (DA) or a uniform price auction (UPA). Using proprietary data on auctions during 2006–2013, we find that (a) the first stage underwriting auction generates significant information, including predicting the likelihood of devolvement, and bid shading, and (b) the outcome of the underwriting auction may generate enough asymmetry amongst bidders that may make DA dominate UPA in certain counterfactual situations. We document that the unique two-stage auction design provides a market-driven mechanism to simultaneously insure against auction failures and produce information about the quality of the underlying issue. This paper was accepted by Karl Diether, finance.