Common ownership, market power, and innovation

examine the effects of overlapping ownership on market power when there are external effects across firms. This is done in an oligopoly model with cost-reducing innovation with technological spillovers where firms have an overlapping ownership structure based largely on López and Vives (2019). The model allows for Cournot competition with homogeneous product and for Bertrand with differentiated products as well as for strategic effects of R&D investment. It derives positive testable implications and normative results to inform polic

Dynamic trading and asset prices: Keynes vs. Hayek

We investigate the dynamics of prices, information, and expectations in a competitive, noisy, dynamic asset pricing equilibrium model with long-term investors. We argue that the fact that prices can score worse or better than consensus opinion in predicting the fundamentals is a product of endogenous short-term speculation. For a given positive level of residual pay-off uncertainty, if liquidity trades display low persistence, rational investors act like market makers and accommodate the order flow and prices are farther away from fundamentals compared to consensus. This defines a "Keynesian" region; the complementary region is "Hayekian" in that rational investors chase the trend and prices are systematically closer to fundamentals than average expectations. The standard case of no residual uncertainty and liquidity trading following a random walk is on the frontier of the two regions and identifies the set of deep parameters for which rational investors abide by Keynes' dictum of concentrating on an asset "long-term prospects and those only". The analysis also explains momentum and reversal in stock returns and how accommodation and trend-chasing strategies differ from these phenomena

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

General equilibrium oligopoly and ownership structure

We develop a tractable general equilibrium framework in which firms are large and have market power with respect to both products and labor, and in which a firm's decisions are affected by its ownership structure. We characterize the Cournot–Walras equilibrium of an economy where each firm maximizes a share‐weighted average of shareholder utilities—rendering the equilibrium independent of price normalization. In a one‐sector economy, if returns to scale are non‐increasing, then an increase in “effective” market concentration (which accounts for common ownership) leads to declines in employment, real wages, and the labor share. Yet when there are multiple sectors, due to an intersectoral pecuniary externality, an increase in common ownership could stimulate the economy when the elasticity of labor supply is high relative to the elasticity of substitution in product markets. We characterize for which ownership structures the monopolistically competitive limit or an oligopolistic one is attained as the number of sectors in the economy increases. When firms have heterogeneous constant returns to scale technologies, we find that an increase in common ownership leads to markets that are more concentrated

¿Qué hay de nuevo en la Rizartrosis?

La rizartrosis en el momento actual está en periodo de avance, ya que nuevos descubrimientos biomecánicos sobre que ligamento es más importante para la estabilidad, e histológicos con el hallazgo de mecanoreceptores en los ligamentos abren un nuevo abanico de posibilidades terapéuticas con el control neuromuscular. La clasificación de Eaton y Littler sigue vigente actualmente, aunque hay nuevas propuestas como el índice radiológico para la artrosis del pulgar. El tratamiento poco ha variado, ya que la trapecectomía sigue siendo una opción válida, pero numerosas técnicas han sido desarrolladas, sin tener ningún estudio que confirme la superioridad de alguna con las demás. Últimamente, nuevas técnicas como la artroscopia, o la utilización de dispositivos tipo Tightrope®, se empiezan a utilizar, sin tener todavía estudios a largo plazo que nos indiquen si son realmente eficaces.Nowadays, osteoarthritis of the thumb is breakthrough time. Thaks to the new biomechanical findings which ligament is more important for stability, and the histological finding of tha mechanoreceptors in the ligaments, that open up a new range of therapeutic possibilities with neuromuscular control. The classification of Eaton and Littler is still currently in force, although there are new proposals as the radiological index for osteoarthritis of the thumb. Treatment has changed little, the trapeziectomy remains as an option, but many techniques have been developed without any studies that confirm the superiority of one with the other ones. Recently, new techniques such as arthroscopy, or use Tightrope® type devices are beginning to use, without yet having longterm studies that tell us whether they are really effective

Costly interpretation of asset prices

We propose a model in which investors cannot costlessly process information from asset prices. At the trading stage, investors are boundedly rational, and their interpretation of prices injects noise into the price, generating a source of endogenous noise trading. Our setup predicts price momentum and yields excessive return volatility and excessive trading volume. In an overall equilibrium, investors optimally choose sophistication levels by balancing the benefit of beating the market against the cost of acquiring sophistication. There can exist strategic complementarity in sophistication acquisition, leading to multiple equilibria

Leishmaniosis felina a propósito de un caso clínico : ¿Nos olvidamos de que existe?

En este trabajo se describe un caso de leishmaniosis felina con sintomatología cutánea y sistémica, así como el protocolo diagnóstico realizado. También se exponen las razones por las cuales se trata de una enfermedad que debemos tenerla en cuenta en nuestra práctica diaria y, por lo tanto, en nuestros diagnósticos diferenciales

Competition in the Supply Option Market

This paper develops a multiattribute competition model for procurement of short life-cycle products. In such an environment, the buyer installs dedicated production capacity at the suppliers before demand is realized. Final production orders are decided after demand materializes. Of course, the buyer is reluctant to bear all the capacity and inventory risk, and thus signs flexible contracts with several suppliers. We model the suppliers' offers as option contracts, where each supplier charges a reservation price per unit of capacity and an execution price per unit of delivered supply. These two parameters illustrate the trade-off between total price and flexibility of a contract, which are both important to the buyer. We model the interaction between suppliers and the buyer as a game in which the suppliers are the leaders and the buyer is the follower. Specifically, suppliers compete to provide supply capacity to the buyer, and the buyer optimizes its expected profit by selecting one or more suppliers. We characterize the suppliers' equilibria in pure strategies for a class of customer demand distributions. In particular, we show that this type of interaction gives rise to cluster competition. That is, in equilibrium suppliers tend to be clustered in small groups of two or three suppliers each, such that within the same group all suppliers use similar technologies and offer the same type of contract. Finally, we show that in equilibrium, supply chain inefficiencies—i.e., the loss of profit due to competition—are at most 25% of the profit of a centralized supply chain.United States. Office of Naval Research (contract N00014-95-1-0232)United States. Office of Naval Research (contract N00014-01-1-0146)National Science Foundation (U.S.) (contract DMI-0085683)National Science Foundation (U.S.) (DMI-0245352)National Science Foundation (U.S.) (CMMI-0758069)Massachusetts Institute of Technology. Center for Digital BusinessUniversity of Navarra. IESE Business School (CIIL International Center for Logistics Research

Wholesale Price Discrimination: Innovation Incentives and Upstream Competition

In intermediate goods markets where there are alternative supply sources, wholesale price discrimination may enhance retailersíinnovation incentives. We consider a vertical chain where a dominant Örm and a competitive fringe supply imperfect substitutes to duopolistic retailers which carry both varieties. We show that a ban on price discrimination by the dominant supplier makes uniform pricing credible and reduces retailersíincentives to decrease the cost of acquiring the competitively supplied variety, leading to higher upstream proÖts and lower downstream welfare. Our analysis complements existing results by identifying a novel channel through which wholesale price discrimination can improve dynamic e¢ ciency of the market