From bargaining solutions to claims rules: a proportional approach

Is it important to negotiate on proportions rather than on numbers? To answer this question, we analyze the behavior of well-known bargaining solutions and the claims rules they induce when they are applied to a "proportionally transformed" bargaining set SP -so-called bargaining-in-proportions set. The idea of applying bargaining solutions to claims problems was already developed in Dagan and Volij (1993). They apply the bargaining solutions over a bargaining set that is the one de ned by the claims and the endowment. A comparison among our results and theirs is provided. Keywords: Bargaining problem, Claims problem, Proportional, Constrained Equal Awards, Constrained Equal Losses, Nash bargaining solution. JEL classi fication: C71, D63, D71.

Supply Multipliers in Two Regional Economies

This paper focuses on the analysis of the economic impact that sectorial total factor productivity – or valued added - gains have on two regional Spanish economies (Catalonia and Extremadura). In particular it is studied the quantitative effect that each sector’s valued added injections has on household welfare (real disposable income), on the consumption price indices and factor relative prices, on real production (GDP) and on the government and foreign net income. To do that, we introduce the concept of supply multiplier. The analytical approach consists of a computable general equilibrium model, in which it is assumed perfect competition and cleared markets of goods and factors. All the parameters and exogenous variables of the model are calibrated by means of two social accounting matrices, one for each region under study. The results allow identifying those sectors with the greatest multipliers impact on consumer welfare as the key sectors in the regional economies. Keywords: efficiency gains, supply multipliers, key sectors, computable general equilibrium. JEL Classification: C68, R13.

Irregular to regular sampling, denoising and deconvolution

We propose a restoration algorithm for band limited images that considers irregular(perturbed) sampling, denoising, and deconvolution. We explore the application of a family ofregularizers that allow to control the spectral behavior of the solution combined with the irregular toregular sampling algorithms proposed by H.G. Feichtinger, K. Gr¨ochenig, M. Rauth and T. Strohmer.Moreover, the constraints given by the image acquisition model are incorporated as a set of localconstraints. And the analysis of such constraints leads to an early stopping rule meant to improvethe speed of the algorithm. Finally we present experiments focused on the restoration of satellite images, where the micro-vibrations are responsible of the type of distortions we are considering here. We will compare results of the proposed method with previous methods and show an extension tozoom.

Derivats financers al mercat espanyol: el Model de Black-Scholes i corbes de volatilitat per opcions sobre l'índex niniIBEX-35

El nostre treball es centrarà en conèixer i aprendre les nocions bàsiques del mercat financer espanyol, primer; i aplicar uns coneixements per veure si es verifica unahipòtesi plantejada, després. La incògnita que volem resoldre és la següent: comprovarsi tots els supòsits i resultats que faciliten els models teòrics emprats en l’estudi dels mercats financers a l’hora de la veritat es compleixen.D’entre els múltiples conceptes que ens proporcionen els estudis de mercatsfinancers ens centrarem sobretot en el model de Black-Scholes i els somriures devolatilitat per desenvolupar el nostre treball. Després de cercar les dades necessàries a través de la web del M.E.F.F., entrevistar-nos amb professionals del sector i fer un seguiment d’aproximadament dos mesos dels moviments de les opcions sobre l’Índex Mini-Íbex 35, amb l’ajuda d’un programa informàtic en llenguatge C, hem calculat les corbes de volatilitat de les opcions sobre l’Índex Mini-Íbex 35.Les conclusions més importants que hem extret són que el Model de Black-Scholes, malgrat va revolucionar el món dels mercats financers, està basat en 2 supòsits que no es compleixen a la realitat: la distribució lognormal del preu de les accions i unavolatilitat constant. Tal i com hem pogut comprovar, la corba de volatilitat de lesopcions sobre l’Índex Mini-Íbex 35 és decreixent amb el preu d’exercici i laMoneyness, tal i com sostenen les teories dels somriures de volatilitat; per tant, no és constant. A més, hem comprovat que a mesura que s’apropa el venciment d’una opció,el preu acordat de l’actiu subjacent a l’opció s’apropa al preu de mercat.

Grinder's Group Mastery Theory : scientific research and its application to classroom teaching

Estudi centrat en el paper de la comunicació no verbal com a eina docent per a la gestió de l’aula, prenent com a referència el model de comunicació de Michael Grinder (Pentimento), basat en la Programació Neuro-lingüística (PNL). Aquest model s’analitza i es compara amb altres models i estudis sobre la comunicació no verbal, per establir-ne similituds i diferències. Per tal d’avaluar l’eficàcia de les tècniques de gestió de l’aula a través de la comunicació no verbal proposades per Grinder en un context educatiu real, s’inclouen i s’analitzen enregistraments de la implementació de diferents tècniques en un institut de secundària de Catalunya. Tota la informació recollida i analitzada permet valorar i ressaltar com és de significatiu tot allò que s’expressa més enllà del llenguatge, i per tant, com són d’importants i d’útils les habilitats comunicatives d’un professor en la seva tasca d’ensenyar.

Accelerated tumor invasion under non-isotropic cell dispersal in glioblastomas

Glioblastomas are highly diffuse, malignant tumors that have so far evaded clinical treatment. The strongly invasive behavior of cells in these tumors makes them very resistant to treatment, and for this reason both experimental and theoretical efforts have been directed toward understanding the spatiotemporal pattern of tumor spreading. Although usual models assume a standard diffusion behavior, recent experiments with cell cultures indicate that cells tend to move in directions close to that of glioblastoma invasion, thus indicating that a biasedrandom walk model may be much more appropriate. Here we show analytically that, for realistic parameter values, the speeds predicted by biased dispersal are consistent with experimentally measured data. We also find that models beyond reaction–diffusion–advection equations are necessary to capture this substantial effect of biased dispersal on glioblastoma spread

Dispersal probability distributions and the wave-front speed problem

The speed and width of front solutions to reaction-dispersal models are analyzed both analytically and numerically. We perform our analysis for Laplace and Gaussian distribution kernels, both for delayed and nondelayed models. The results are discussed in terms of the characteristic parameters of the models

Optimal management of microgrids

Desenvolupament dels models matemàtics necessaris per a controlar de forma òptima la microxarxa existent als laboratoris del Institut de Recerca en Energia de Catalunya. Els algoritmes s'implementaran per tal de simular el comportament i posteriorment es programaran directament sobre els elements de la microxarxa per verificar el seu correcte funcionament.. Desenvolupament dels models matemàtics necessaris per a controlar de forma òptima la microxarxa existent als laboratoris del Institut de Recerca en Energia de Catalunya. Els algoritmes s'implementaran per tal de simular el comportament i posteriorment es programaran directament sobre els elements de la microxarxa per verificar el seu correcte funcionament.

Predicting the potential for lightning activity in mediterranean storms based on the WRF model dynamic and microphysical fields

A new parameter is introduced: the lightning potential index (LPI), which is a measure of the potential for charge generation and separation that leads to lightning flashes in convective thunderstorms. The LPI is calculated within the charge separation region of clouds between 0 C and 20 C, where the noninductive mechanism involving collisions of ice and graupel particles in the presence of supercooled water is most effective. As shown in several case studies using the Weather Research and Forecasting (WRF) model with explicit microphysics, the LPI is highly correlated with observed lightning. It is suggested that the LPI may be a useful parameter for predicting lightning as well as a tool for improving weather forecasting of convective storms and heavy rainfall.

Modelling of weather radar echoes from anomalous propagation using a hybrid parabolic equation method and NWP model data

Contamination of weather radar echoes by anomalous propagation (anaprop) mechanisms remains a serious issue in quality control of radar precipitation estimates. Although significant progress has been made identifying clutter due to anaprop there is no unique method that solves the question of data reliability without removing genuine data. The work described here relates to the development of a software application that uses a numerical weather prediction (NWP) model to obtain the temperature, humidity and pressure fields to calculate the three dimensional structure of the atmospheric refractive index structure, from which a physically based prediction of the incidence of clutter can be made. This technique can be used in conjunction with existing methods for clutter removal by modifying parameters of detectors or filters according to the physical evidence for anomalous propagation conditions. The parabolic equation method (PEM) is a well established technique for solving the equations for beam propagation in a non-uniformly stratified atmosphere, but although intrinsically very efficient, is not sufficiently fast to be practicable for near real-time modelling of clutter over the entire area observed by a typical weather radar. We demonstrate a fast hybrid PEM technique that is capable of providing acceptable results in conjunction with a high-resolution terrain elevation model, using a standard desktop personal computer. We discuss the performance of the method and approaches for the improvement of the model profiles in the lowest levels of the troposphere.

Valores medios del coeficiente de atenuación de las ondas Rayleigh para Europa occidental

En este estudio presentamos los valores medios del coeficiente de atenuación de las ondas Rayleigh para Europa occidental, obtenidos a partir del estudio de tres terremotos situados en las Azores, Sicilia y Mar Negro y registrados por estaciones europeas. Los resultados presentan una gran dispersión, mostrando claramente la inhomogeneidad de la zona. Para el terremoto del Atlántico, los resultados son muy coherentes y presentan unos valores del coeficiente de atenuación comparables, aunque ligeramente superiores para periodos cortos, a los haliados para la region estable de la placa Euroasiática.

Anelasticidad de la zona estable euroasiática y de la zona europea occidental

La teoria de inversión en su forma estocastica ha sido aplicada a dos conjuntos de coeficientes de atenuación de las ondas de Rayleigh correspondientes a la zona estable Euroasiatica y a la zona Europea Occidental. Los resultados obtenidos muestran que las propiedades anelásticas bajo dichas zonas son distintas. Europa Occidental se halla caracterizada por valores mas bajos de los factores especificos de calidad de las ondas de cizalla(Qbeta) que los correspondientes a la zona Estable Euroasiática. Las profundiades a las que los valores de Qbeta decrecen más rápidamente son alrededorde 60 km para Europa Occidental y de 40 km para la zona Estable Euroasiática. La comparación con un estudio de atenuación en el Océano Atlántico muestra que los coeficientes de atenuación correspondientes a la zona Europea Occidental pueden ser considerados representativos para dicha zona.

The relationship of capitalization period length with market portfolio composition and betas

Beta coefficients are not stable if we modify the observation periods of the returns. The market portfolio composition also varies, whereas changes in the betas are the same, whether they are calculated as regression coefficients or as a ratio of the risk premiums. The instantaneous beta, obtained when the capitalization frequency approaches infinity, may be a useful tool in portfolio selection.

The mean-variance model from the inverse of the variance-covariance matrix

En este artículo, a partir de la inversa de la matriz de varianzas y covarianzas se obtiene el modelo Esperanza-Varianza de Markowitz siguiendo un camino más corto y matemáticamente riguroso. También se obtiene la ecuación de equilibrio del CAPM de Sharpe.