Nova troballa d'inscripcions funeràries a la parròquia de Fortià (Alt Empordà)

Notícia sobre la troballa de vuit làpides funeràries i dues osseres a l'interior de l'església de Sant Julià i Santa Basilissa de Fortià (Alt Empordà

Essays on firms, competition and public procurement

This thesis consists of three chapters that study the interaction between public procurement and firms’ behavior. Chapters 1 and 2 study the pharmaceutical market in Ecuador, where, as in many middle-income countries, large public and private sectors coexist. Since the same set of firms often serve both sectors, there are important dependencies in the firms’ decisions across sectors that can affect medicine supply. Using a novel dataset, in Chapter 1, I provide reduced-form evidence that firms’ pricing decisions in the public and private sectors, indeed, respond to cross-sector incentives. Motivated by this evidence, in Chapter 2, I develop and estimate a model in which firms compete in auctions in the public sector and in prices in the private market. I use the model to quantify the effects of increasing the number of participants in the auction, changing the reserve prices, and introducing local-preference rules in the auction on the supply decisions in both sectors. Chapter 3, co-authored with Felipe Brugués and Samuele Giambra, uses detailed ownership information of private firms in Ecuador and the identity of the universe of bureaucrats to provide evidence of the welfare consequences of the misallocation of public procurement contracts due to political connections. Using an event study design, we show that after establishing a political connection, firms are more likely to win government contracts and charge, on average, 7% higher prices than unconnected firms. Production function estimates reveal that politically connected firms are, on average, less efficient. We propose a framework to estimate the losses to society that derive from the under-provision of public services caused by price inflation and from the excess costs generated by the misallocation of government contracts

Supersymmetric quantum mechanics from wrapped branes

We explicitly construct a solution of eight-dimensional gauged supergravity representing D6-branes wrapped on six-cycles inside Calabi-Yau fourfolds. The solution preserves two supercharges and asymptotically is a cone with the coset space SU(2)^4/U(1)^3 as its base. It is shown to correspond to an M-theory compactification on a Calabi-Yau manifold with SU(5) holonomy and we discuss in detail its geometrical and topological features. We also construct a family of related higher dimensional metrics having SU(n+1) holonomy, which of course have no brane interpretation.Comment: 15 pages, Latex. V2: Physics Letters B version; discussion on fluxes has been modifie