Bidding markets with financial constraints

We develop a model of bidding markets with financial constraints a la Che and Gale (1998b) in which two firms optimally choose their budgets. First, we provide an alternative explanation for the dispersion of markups and “money left on the table” across procurement auctions. Interestingly, this explanation does not hinge on significant private information but on differences, both endogenous and exogenous, in the availability of financial resources. Second, we explain why the empirical analysis of the size of markups may be biased downwards or upwards with a bias positively correlated with the availability of financial resources when the researcher assumes that the data are generated by the standard auction model. Third, we show that large concentration and persistent asymmetries in market shares together with occasional leadership reversals can arise as a consequence of the firms internal financial decisions even in the absence of exogenous shocks

Why Do European Governments Favor Religion?

This paper explores a highly controversial issue: while most European countries are undergoing a clear and well-documented process of secularization, the governments of these countries widely support religious institutions. The arguments put forward by the median voter seem insufficient to explain the data. We show that if political parties are allowed to take an ideological position with respect to religion, the observed deviations from the most preferred policy by the median voter could be explained. The assumptions of our model are tested using European data. We observe that citizens are concerned about secularization, but that there are differences between religious and non-religious citizens as we assume. In addition, and in consonance with our assumptions, the percentage of religious-averse inhabitants is very small.religiosity, favoritism, voting, political economics.

D-instanton and polyinstanton effects from type I' D0-brane loops

We study non-perturbative D(-1)-instanton corrections to quartic gauge and curvature couplings in 8d type IIB orientifolds, in terms of a one-loop computation of BPS D0-branes in T-dual type I' models. The complete perturbative and non-perturbative results are determined by the BPS multiplicities of perturbative open strings and D0-brane bound states in the 9d type I' theory. Its modular properties admit a geometric interpretation by lifting to Horava-Witten theory. We use the type I' viewpoint to motivate a proper interpretation of 8d and 4d polyinstanton effects, consistent with heterotic - type II orientifold duality.Comment: 37 pages, 2 figures, clarifications and references adde

A structural approach including the behavior of collagen cross-links to model patient-specific human carotid arteries

The final publication is available at Springer via http://dx.doi.org/10.1007/s10439-014-0995-7The objective of this work is to develop a remodeling model for biological matter coupling two different processes in a 3D framework: reorientation of the preferential direction of a given fibered structure and reorientation of the fibrils or filaments that make up such a structure. This work uses the microsphere-based approach to take into account the micro mechanics involved in biological fibered structures regarding both their passive behavior and the reorientation of their micro constituents. Moreover, the macro behavior of the material as a whole is obtained by means of homogenizing the underlying micro response. We associate the orientation space of the integration directions to the physical space of micro-fibrils. To approximate the directional distribution of the fibrils within each fiber bundle, a Bingham probability orientation density function is introduced into the Helmholtz energy function. With all these assumptions, the problem is studied from an energetic point of view, describing the dissipation inherent to remodeling processes, and the evolution equations for both reorientations (change in preferential direction of the network and change in shape of the fibril distribution) re obtained. The model is included in a finite element code which allows computing different geometries and boundary value problems. This results in a complete methodology for characterizing the reorientation evolution of different fibered biological structures, such as cells. Our results show remodeling of fibered structures in two different scales, presenting a qualitatively good agreement with experimental findings in cell mechanics. Hierarchical structures align in the direction of the maximum principal direction of the considered stimulus and narrow in the perpendicular direction. The dissipation rates follows predictable trends although there are no experimental findings to date for comparison. The incorporation of metabolic processes and an insight into cell-oriented mechano-sensing processes can help to overcome the limitations involved.Peer ReviewedPostprint (author's final draft

Automating property-based testing of evolving web services

Web services are the most widely used service technology that drives the Service-Oriented Computing~(SOC) paradigm. As a result, effective testing of web services is getting increasingly important. In this paper, we present a framework and toolset for testing web services and for evolving test code in sync with the evolution of web services. Our approach to testing web services is based on the Erlang programming language and QuviQ QuickCheck, a property-based testing tool written in Erlang, and our support for test code evolution is added to Wrangler, the Erlang refactoring tool. The key components of our system include the automatic generation of initial test code, the inference of web service interface changes between versions, the provision of a number of domain specific refactorings and the automatic generation of refactoring scripts for evolving the test code. Our framework provides users with a powerful and expressive web service testing framework, while minimising users' effort in creating, maintaining and evolving the test model. The framework presented in this paper can be used by both web service providers and consumers, and can be used to test web services written in whatever language; the approach advocated here could also be adopted in other property-based testing frameworks and refactoring tools

EL ROL DEL ESTADO EN LA INTERNACIONALIZACION DE LA EDUCACION SUPERIOR EN ARGENTINA Y AMERICA LATINA NOTAS PRELIMINARES

Según Sebastián (2005) la internacionalización de la educación superior tiene un carácter dual: uno que se expresa al interior de la universidad y que busca mejorar la calidad y pertinencia, por lo que incluye la dimensión internacional en la cultura institucional y los estándares internacionales .La internacionalización hacia el exterior contempla la proyección internacional de la oferta institucional en la cual se trata de ampliar la visibilidad, el reconocimiento y el ámbito de actuación de la institución. Los países no participan del mismo modo en este proceso. En el mundo anglosajón la internacionalización se incorpora en la agenda desde la mirada de las oportunidades que ofrece la transnacionalización para incorporar estudiantes extranjeros y exportar capacidades docentes. En Europa, la declaración de Bolonia de 1999, declaración conjunta de los ministros europeos de educación, tuvo un papel central al consensuar “un área europea de educación superior”(EEES), promoviendo la cooperación entre instituciones, la movilidad estudiantil, sistemas de títulos homologables pero respetando la diversidad de culturas y la autonomía de las Universidades. En la región latinoamericana, y bajo el estímulo de la experiencia europea, la internacionalización se instaló en las agendas gubernamentales un poco más tarde. Dan cuenta de ello, las diferentes Declaraciones de la Cumbres Iberoamericanas donde los Jefes de Estado han remarcado la importancia de generación de espacio iberoamericano de conocimiento. Nuestro trabajo tiene como objetivo analizar las fortalezas y debilidades de las políticas de internacionalización de la educación superior en Argentina, en el período 1990 hasta la actualidad, con el objeto de reflexionar críticamente sobre su impacto en materia de equidad, inclusión, y calidad, a la luz de otras experiencias latinoamericanas. Se pretende asimismo, reflexionar en torno a las fortalezas, limitaciones y desafíos del rol del estado en el proceso de internacionalización en tanto actor central para garantizar el derecho a una educación inclusiva y de calidad