Treasury auctions in Spain: a linear approach

Abstract. The majority of Treasuries use discriminatory auctions to sell government debt. A few Treasuries use uniform auctions. The Spanish Treasury is the only one that uses a hybrid format of discriminatory and uniform auctions. All Treasury auctions are multiple-unit multiple-bid auctions, usually assumed to be common and unknown value auctions. Taking in account these features, we analyze the Spanish auction format, taking a linear approximation to bidders' multiple bids, and characterize a parameter set in which the Spanish format gives higher expected seller's revenue than discriminatory and uniform auctions. Policy implications are obtained by calibrating theoretical results with data. We thank S. Nu?ez, and seminar participants at GREQAM, CEFI, the 1999 CEF meeting in Boston and the 57th European Meeting of the Econcometric Society for suggestions. We are especially grateful to two anonymous referees for detailed comments that greatly improved the paper. Any error is our responsability. The authors express their thanks for financial support to Ministerio de Ciencia y Teconologia from Proyecto SEC2000-0723, n_o 9114.