A Computable general equilibrium approach to hypothetical extractions and missing links

Identifying key sectors or key locations in an interconnected economy is of paramount importance for improving policy planning and directing economic strategy. Hence the relevance of categorizing them and hence the corresponding need of evaluating their potential synergies in terms of their global economic thrust. We explain in this paper that standard measures based on gross outputs do not and cannot capture the relevant impact due to self- imposed modeling limitations. In fact, common gross output measures will be systematically downward biased. We argue that an economy wide Computable General Equilibrium (CGE) approach provides a modeling platform that overcomes these limitations since it provides (i) a more comprehensive measure of linkages and (ii) an alternate way of accounting for links' relevance that is in consonance with standard macromagnitudes in the National Income and Product Accounts.

Empleo de óptica adaptativa y fluorescencia en un oftalmoscopio laser de barrido para el registro de células

Estudio elaborado a partir de una estancia en la Universidad de Rochester, Estados Unidos, de octubre del 2006 a enero del 2007. La estancia realizada en la Universidad de Rochester estuvo orientada al aprendizaje en profundidad del oftalmoscopio láser de barrido. El oftalmoscopio láser de barrido emplea una técnica confocal con la finalidad de visualizar diferentes estructuras retinianas en seres vivos. El instrumento diseñado y desarrollado en el Centro de Ciencias de la Visión incorpora un sistema de óptica adaptativa y fluorescencia. La óptica adaptativa aplicada en este oftalmoscopio tiene como objetivo corregir las aberraciones existentes en el ojo y así permitir observar detalles de la retina que de otra forma se verían emborronados. De esta forma se consigue alcanzar valores de resolución muy cercanos a los impuestos por difracción. Por otro lado el uso de fluorescencia tiene por objetivo el permitir la visualización de células y estructuras que, de no ser teñidas, son transparentes a la luz y visible. Esta técnica se ha estado utilizando principalmente en primates y ratas, aunque actualmente también se están llevando a cabo medidas de células de epitelio pigmentario en seres humanos ya que el pigmento contenido en estas células permite la aplicación de la fluorescencia sin necesidad de utilizar tinción.

Model structures on the category of small double categories

In this paper we obtain several model structures on DblCat, the category of small double categories. Our model structures have three sources. We first transfer across a categorification-nerve adjunction. Secondly, we view double categories as internal categories in Cat and take as our weak equivalences various internal equivalences defined via Grothendieck topologies. Thirdly, DblCat inherits a model structure as a category of algebras over a 2-monad. Some of these model structures coincide and the different points of view give us further results about cofibrant replacements and cofi brant objects. As part of this program we give explicit descriptions and discuss properties of free double categories, quotient double categories, colimits of double categories, and several nerves and categorifications.

Olympic education experiences: the sponsorship in the promotion of Olympic values

This text was presented at the 16th International Seminar on Olympic Studies for Postgraduate Students that was organised by the International Olympic Academy in Ancient Olympia, from 1st to 30th July 2008. First here are reported, fundamental concepts on Olympics such as the Olympic values and the educational mandate of Pierre de Coubertin, the Olympic brand and symbols, the sponsorship and the Olympic partner programme. Then there is a chapter regarding the Top sponsors educational initiatives on Olympic values, and specially, describing the Olympic sponsors involvement in education and Top sponsors educational activities. And finally, the author analyses the sponsorship role in the promotion of Olympic Values Education, providing conclusions, comments on future and perspectives and some recommendations.

The new role of the mass media in the construction of sport and Olympic values

This paper was presented in the International Symposium on Toward the Creation of New-Sport Cultures, undertaken in Osaka, Japan, in January 28, 1996. The main purpose is to make an interpretation of the cultural values of sport and Olympism in contemporary society, considering the enormous influence that the media have on them.

Formal deformations of Poisson structures in low dimensions

In this paper, we study formal deformations of Poisson structures, especially for three families of Poisson varieties in dimensions two and three. For these families of Poisson structures, using an explicit basis of the second Poisson cohomology space, we solve the deformation equations at each step and obtain a large family of formal deformations for each Poisson structure which we consider. With the help of an explicit formula, we show that this family contains, modulo equivalence, all possible formal eformations. We show moreover that, when the Poisson structure is generic, all members of the family are non-equivalent.

Earnings management and cultural values

Using theory and empirical data from social psychology to measure for cultural differences between countries, we study the effect of individualism as defined by Hofstede (1980) and egalitarianism as defined by Schwartz (1994, 1999, 2004) on earnings management. We find a significant influence of both cultural measures. In line with Licht et al. (2004), who argue that individualistic societies may be less susceptible to corruption, we find that countries scoring high on individualism tend to have lower levels of earnings management. In addition, we find that egalitarianism, defined as a society's cultural orientation with respect to intolerance for abuses of market and political power, is negatively related with earnings management. Our results are robust to different specifications and controls. The main message of this paper is that besides formal institutions, cultural differences are relevant to explain earnings management behaviour. We think that our work adds to the understanding of the importance of cultural values in managerial behaviour across countries contributing to the literature on earnings management and law and institutions.

Dividends and weighted values in games with externalities

We consider cooperative environments with externalities (games in partition function form) and provide a recursive definition of dividends for each coalition and any partition of the players it belongs to. We show that with this definition and equal sharing of these dividends the averaged sum of dividends for each player, over all the coalitions that contain the player, coincides with the corresponding average value of the player. We then construct weighted Shapley values by departing from equal division of dividends and finally, for each such value, provide a bidding mechanism implementing it.

Free Mobility and Taste-Homogeneity of Jurisdiction Structures

We consider a population of agents distributed on the unit interval. Agents form jurisdictions in order to provide a public facility and share its costs equally. This creates an incentive to form large entities. Individuals also incur a transportation cost depending on their location and that of the facility which makes small jurisdictions advantageous. We consider a fairly general class of distributions of agents and generalize previous versions of this model by allowing for non-linear transportation costs. We show that, in general, jurisdictions are not necessarily homogeneous. However, they are if facilities are always intraterritory and transportation costs are superadditive. Superadditivity can be weakened to strictly increasing and strictly concave when agents are uniformly distributed. Keywords: Consecutiveness, stratification, local public goods, coalition formation, country formation. JEL Classification: C71 (Cooperative Games), D71 (Social Choice; Clubs; Committees; Associations), H73 (Interjurisdictional Differentials and Their Effects).

Un estudi de les argumentacions d’estudiants anglesos i catalans en activitats de resolució de problemes no formals en ciències i de les estratègies didàctiques dels professors que afavoreixen l’argumentació a les classes

Una de les contribucions de la recerca sobre concepcions prèvies dels estudiants en ciències durant els darrers 25 anys ha estat mostrar la influència del context sociocultural dels nois i noies en les idees i concepcions que desenvolupen i mantenen des de la seva infància. Hi ha l’acord que algunes diferències en les concepcions poden dependre de la cultura social en la qual s’integren. Alguns investigadors també pensen que els esquemes argumentatius també poden ser influenciats per la cultura de les comunitats. Els contextos Català i Anglès semblen similars, ambdós formen part del context cultural de les societats desenvolupades; per tant, podem pensar que els esquemes argumentatius que els estudiants apliquen, poden tenir moltes similituds, però també importants diferències. Les dades analitzades provenen de les respostes escrites dels estudiants individuals i de les transcripcions de 8 grups de discussió sobre quatre tasques. L’anàlisi es fa a tres nivells: 1)comparació del nombre d’arguments entre tasques i entre països, 2) qualitativa i descriptiva comparació entre tipus d’esquemes argumentatius per tasques i per països i 3) explicació de tipus d’esquemes argumentatius que es donen molt, i identificació d’estructures argumentatives complexes que lliguen diversos esquemes en un argument més gran i que poden caracteritzar l’argumentació d’alguns grups (aplicant Toulmin) i que poden ser indicadors d’aspectes cooperatius i de canvis de punts de vista en les discussions. Els resultants ens indiquen que encara que els estudiants Catalans dediquen més temps a les discussions, la ratio nombre d’esquemes per unitat de temps és similar als dos països. S’han trobar algunes diferències entre tipus d'esquemes per països i per tasques, també que molts arguments es basen en valors i idees preconcebudes. S’han pogut identificar també algunes estructures argumentatives complexes no gaire comunes.

Moduli of flat conformal structures of hyperbolic type

"Vegeu el resum a l'inici del document del fitxer adjunt."

Heterogeneous dynamics, aggregation and the persistence of economic shocks

It has been recently emphasized that, if individuals have heterogeneous dynamics, estimates of shock persistence based on aggregate data are significatively higher than those derived from its disaggregate counterpart. However, a careful examination of the implications of this statement on the various tools routinely employed to measure persistence is missing in the literature. This paper formally examines this issue. We consider a disaggregate linear model with heterogeneous dynamics and compare the values of several measures of persistence across aggregation levels. Interestingly, we show that the average persistence of aggregate shocks, as measured by the impulse response function (IRF) of the aggregate model or by the average of the individual IRFs, is identical on all horizons. This result remains true even in situations where the units are (short-memory) stationary but the aggregate process is long-memory or even nonstationary. In contrast, other popular persistence measures, such as the sum of the autoregressive coefficients or the largest autoregressive root, tend to be higher the higher the aggregation level. We argue, however, that this should be seen more as an undesirable property of these measures than as evidence of different average persistence across aggregation levels. The results are illustrated in an application using U.S. inflation data.

Condensation of polyhedric structures onto soap films

We study the existence of solutions to general measure-minimization problems over topological classes that are stable under localized Lipschitz homotopy, including the standard Plateau problem without the need for restrictive assumptions such as orientability or even rectifiability of surfaces. In case of problems over an open and bounded domain we establish the existence of a “minimal candidate”, obtained as the limit for the local Hausdorff convergence of a minimizing sequence for which the measure is lower-semicontinuous. Although we do not give a way to control the topological constraint when taking limit yet— except for some examples of topological classes preserving local separation or for periodic two-dimensional sets — we prove that this candidate is an Almgren-minimal set. Thus, using regularity results such as Jean Taylor’s theorem, this could be a way to find solutions to the above minimization problems under a generic setup in arbitrary dimension and codimension.

Work values, endogenous sentiments and redistribution

We examine the interactions between individual behavior, sentiments and the social contract in a model of rational voting over redistribution. Agents have moral "work values". Individuals' self-esteem and social consideration of others are endogenously determined comparing behaviors to moral standards. Attitudes toward redistribution depend on self-interest and social preferences. We characterize the politico-economic equilibria in which sentiments, labor supply and redistribution are determined simultaneously. The equilibria feature different degrees of "social cohesion" and redistribution depending on pre-tax income inequality. In clustered equilibria the poor are held partly responsible for their low income since they work less than the moral standard and hence redistribution is low. The paper proposes a novel explanation for the emergence of different sentiments and social contracts across countries. The predictions appear broadly in line with well-documented differences between the United States and Europe.