Homotopy groups of generic leaves of logarithmic foliations

We study the homotopy groups of generic leaves of logarithmic foliations on complex projective manifolds. We exhibit a relation between the homotopy groups of a generic leaf and of the complement of the polar divisor of the logarithmic foliation.Comment: Keywords: Foliations, Logarithmic, Topology of Leave

Endogenous spillovers, increased competition and re-organization waves

We consider an entrepreneur that is the sole producer of a cost reducing skill, but the entrepreneur that hires a team to use the skill cannot prevent collusive trade for the innovation related knowledge between employees and competitors. We show that there are two types of diffusion avoiding strategies for the entrepreneur to preempt collusive communication i) setting up a large productive capacity (the traditional firm) and ii) keeping a small team (the lean firm). The traditional firm is characterized by its many "marginal" employees that work short days, receive flat wages and are incompletely informed about the innovation. The lean firm is small in number of employees, engages in complete information sharing among members, that are paid with stock option schemes. We find that the lean firm is superior to the traditional firm when technological entry costs are low and when the sector is immature.Information sharing, endogenous spillovers, physical assets, corporate transformation, stock-options, collussion, trade secrets

New ideas need new space

We develop a setting with weak intellectual property rights, where firms' boundaries, location and knowledge spillovers are endogenous. We have two main results. The first one is that, if communication costs increase with distance, entrepreneurs concerned about information leakage have a benefit from locating away from the industry center: distance is an obstacle to collusive trades between members and non-members. The second result is that we identify a trade-off for the entrepreneur between owning a facility (controlling all its characteristics) and sharing a facility with a {\it non-member} (an agent not involved in production), therefore losing control over some of its characteristics. We focus on ``location" as the relevant characteristic of the facility, but location can be used as a spatial metaphor for other relevant characteristics of the facility. For the entrepreneur, sharing the facility with non-members implies that the latter, as co-owners, know the location (even if they do not have access to it). Knowledge of the location for the co-owners facilitates collusion with employees, what increases leakage. The model yields a benefit for new plants from spatial dispersion (locating at the periphery of the industry), particularly so for new plants of new firms. We relate this result with recent empirical findings on the dynamics of industry location.Intellectual property rights, employee hold-up, secrecy, location, endogenous spillovers

Potential climatic influence on the maximum stand carrying capacity of 15 Mediterranean conifers and broadleaves

Las proyecciones de cambio climático para la cuenca del Mediterráneo predicen un incremento continuo en episodios de sequía y calor extremos, afectando a la dinámica, estructura y composición de las masas forestales. En este contexto, resulta fundamental comprender cómo el clima influye en la relación tamaño-densidad máxima (recta de autoclareo) de estas masas con el fin de diseñar actuaciones de gestión forestal sostenible adaptadas a este nuevo escenario. Este estudio pretende avanzar en esta línea, analizando los potenciales impactos del clima en el Índice de Máxima Densidad (SDImax) de 15 especies forestales pertenecientes a los géneros Pinus, Fagus y Quercus. Para ello se utilizaron las bases de datos del Tercer Inventario Forestal Nacional Español (IFN3) y WorldClim. En primer lugar, se ajustaron rectas de autoclareo básicas mediante regresión cuantílica y se estimaron nuevos valores SDImax de referencia por especie. En un segundo paso, se seleccionaron 35 variables climáticas anuales y periódicas para ajustar rectas de autoclareo dependientes del clima. El mejor modelo climáticodependiente fue seleccionado para cada especie basándonos en el Indice de Información de Akaike con el fin de analizar las tendencias generales y específicas en la variación de SDImax. Para todas las especies de estudio, la influencia del clima sobre el SDImax fue significativa. Los resultados obtenidos mostraron una tendencia común en la variación de SDImax, con valores más pequeños vinculados a condiciones más secas y cálidas, lo que sugiere reducciones potenciales del stock de estas especies bajo futuros escenarios climáticos. En oposición a esta tendencia, el modelo de Pinus nigra sugiere que inviernos más suaves como efecto de incrementos en temperaturas mínimas podrían beneficiar a las especies en zonas de montaña. En general, el estrés hídrico (expresado a través del Indice De Martonne) fue un factor determinante afectando al SDImax de Fagus, mientras que cambios en las temperaturas de primavera y verano explicaron las variaciones SDImax de las especies del género Quercus. Las especies de Pinus se vieron indistintamente afectadas por potenciales variaciones de temperatura y humedad. Todos los modelos climático-dependientes seleccionados mejoraron los modelos básicos y los modelos ajustados en estudios similares, como aquellos que utilizan el Índice de Martonne como variable climática independiente. Nuestros hallazgos destacan la necesidad de utilizar variables climáticas periódicas para caracterizar mejor los impactos climáticos en el SDImax. Los modelos presentados en este estudio permitirán obtener estimaciones más precisas de la máxima densidad admisible por diferentes especies de coníferas y frondosas, proporcionando una herramienta avanzada para la gestión forestal sostenible de masas puras y mixtas mediterráneas bajo diferentes escenarios de cambio climático.Climate change projections for the Mediterranean basin predict a continuous increment in extreme drought and heat episodes, affecting forest dynamics, structure and composition. Understanding how climate influences the maximum size-density relationship (MSDR) is therefore critical to design adaptative silvicultural guidelines based on the potential stand carrying capacity of tree species. With this aim, data from the Third Spanish National Forest Inventory (3NFI) and WorldClim databases were used to analyze climate related variations of the maximum stand carrying capacity for 15 species from the Pinus, Fagus and Quercus genus. First, basic MSDR were fitted using linear quantile regression and observed size-density data from monospecific 3NFI plots. Reference values of maximum stocking, expressed as SDImax, were estimated by species. In a second step, climatedependent MSDR models including 35 different annual and seasonal climatic variables were fitted. The best climate-dependent MSDR model was selected by species according to the Akaike Information Criteria in order to analyze general and species-specific trends in the SDImax variation. Results showed a common trend across species in SDIgenus variation with smaller SDImax values linked to drier and warmer conditions, suggesting potential reductions of the maximum stocking for this species based on projected climatic scenarios. Opposed to this trend, results for Pinus nigra suggest that milder winters as effect of increments in minimum temperatures could beneficiate mountainous species. Humidity (expressed as the De Martonne Index) was found as key driver affecting SDImax of Fagus species, since changes in spring and summer temperatures explained SDImax variations of Quercus species. Pinus species were indistinctively affected by temperature and water stress. All the selected climate-dependent models improved the goodness of fit over the basic and the business-as-usual models including the De Martonne Index as independent climatic variable. Our findings highlight the importance of using specific climatic variables to better characterize climatic impacts on the MSDR. Models presented in this study will allow to obtain more precise estimations of the maximum stocking for different coniferous and broadleaved species, providing an advanced tool for managing Mediterranean pure and mixed forests under different scenarios of climate change.Máster en Gestión Forestal basada en Ciencia de Dato

Pricing to Market at firm level

This paper tries to contribute to the renewed literature about price differences across countries (the so-called border effect). Specifically, it analyzes the reasons underlying changes in relative prices across export/domestic markets for an open economy. The theoretical benchmark, based on the existence of Pricing to Market strategies, also takes into account some hypotheses about the effects of demand variations and market power on prices. The empirical analysis, using firm panel data for the nineties, points out the positive (though small) impact of the exchange rate on the evolution of price ratio. Additionally, the results also suggest a procyclical behavior of prices in both markets, which is positively affected by the degree of competition. Though data do not allow an in-depth analysis, some hypothesis in terms of foreseeable effects of the European Monetary Union on relative prices are provided.

Domestic and foreign price-marginal cost margins: an application to Spanish manufacturing firms

The objective of this paper is to analyse the differences in price-marginal cost margins of the export and domestic markets by the estimation of a multiproduct cost function. We apply this method to a panel of Spanish export manufacturing firms from the period 1990-1997. Some results emerge from the estimations. First, price-marginal cost margins in domestic markets are larger than foreign margins throughout the period. Second, price-marginal cost margins are procyclical in the domestic market but there is no evidence of this behaviour in the foreign markets. Third, there is no evidence that export firms used the devaluation of the currency to increase their margins. Finally, price-cost margins reveal some degree of heterogeneity across industries in both markets.Marginal cost, price-cost margins, translog cost function, export firm

Markups, bargaining power and offshoring: An empirical assessment

This paper tests the pro-competitive effect of imports on product and labour markets for Spanish manufacturing firms in the period 1990-2005. In doing so, it takes into account the type of imported products: final vs intermediate. Markups are estimated following the procedure suggested by Roeger (1995) and including an efficient bargaining model. The observed heterogeneity among firms is parameterized to consider additional product standardization and market concentration. The results support the Imports as Market Discipline hypothesis for importers of final goods, while firms that offshore intermediate inputs show similar markups to non-importers. Additionally, the union bargaining power is smaller the more final-goods oriented imports are and the more homogeneous is the type of goods elaborated by firms.Markups, Offshoring, Bargaining power.

Persistence in inequalities across the Spanish regions

In this paper we investigate several issues concerning persistence in inequalities of relative income per capita among the Spanish regions over 1980-2002. For that purpose we take a Bayesian approach which extends the work by Canova and Marcet (1995). Firstly, we study to what extent there exists a fixed effect bias in the standard cross-section estimates, and we find that the speed of convergence is indeed underestimated. Secondly, we provide a battery of results in which steady states and convergence rates have been obtained for a continuum of prior distributions. Finally, we also deal with persistence in inequalites by determining whether initial conditions matter in the distribution of regional steady states, and our conclusion is that regional disparities tend to persist over time in Spain.Convergence, Inequalities, Bayesian Econometrics, Gibbs sampling

The role of new technologies in the economic growth of Andalucia

This paper explores the contribution of Information and Communication Technologies (ICT) on economic growth and labor productivity growth of Andalucía during 1995-2004. We find that the contribution of ICT assets to total market GVA growth is quantitatively modest. Anyway the contribution to GVA growth and employment growth within the intensive ICT sectors has experienced a considerable increase in Andalucía. Although our analysis detects that intensive ICT sectors exhibit a high productivity level with respect to that of the non intensive ones, our main conclusion is that the advantages that might emerge from the use of ICT are nor yet observable in the economic dynamics of Andalucía, at least in a similar manner to that of the most developed.Information and Communication Technologies, productivity growth, regional growth