Medida del impacto económico de la salida del mercado laboral de trabajadores inmigrantes en la Comunidad de Madrid

This paper analyses the economic impact of the loss of employment suffered by the immigrant population in Madrid’s regional economy during the years of the latest economic crisis, specifically during the period 2010-2016. First, it examines the labour characteristics of the immigrant population, a community mainly employed in unstable and low-skilled jobs and overrepresented in economic sectors that are sensitive to fluctuations in the labour market. Financial crisis forced these workers exiting labour market and the present work focuses on the modelling of this phenomenon by means of the construction of a multisectoral model of the supply-side type, also known as Ghosh model. This analytic approach provides estimates of the direct impacts of the immigrant working population leaving the labour market, and of its indirect and induced impacts on the greater economy.Este trabajo analiza el coste para la economía madrileña de la pérdida de empleos que ha sufrido la población activa extranjera en los años de la crisis, en concreto en el período 2010-2016. En primer lugar, se analizan las características laborales de la población inmigrante, población que en su mayoría cubre puestos de trabajo inestables y de baja cualificación, estando sobrerrepresentada en sectores económicos que son muy sensibles a las fluctuaciones del mercado laboral. La crisis financiera obligó a estos trabajadores a abandonar el mercado laboral y el presente trabajo se centra en la modelización de este fenómeno mediante la construcción de un modelo multisectorial de oferta, también conocido como modelo Ghosh. Este enfoque analítico proporciona estimaciones de los impactos directos en la población trabajadora inmigrante que abandona el mercado laboral, y de los impactos indirectos e inducidos en la economía en general

Critical angular momentum distributions in collapsars: quiescent periods from accretion state transitions in long gamma-ray bursts

The rotation rate in pre-supernova cores is an important ingredient which can profoundly affect the post-collapse evolution and associated energy release in supernovae and long gamma ray bursts (LGRBs). Previous work has focused on whether the specific angular momentum is above or below the critical value required for the creation of a centrifugally supported disk around a black hole. Here, we explore the effect of the distribution of angular momentum with radius in the star, and show that qualitative transitions between high and low angular momentum flow, corresponding to high and low luminosity accretion states, can effectively be reflected in the energy output, leading to variability and the possibility of quiescent times in LGRBs.Comment: 22 pages, 6 figures, 2 Tables, accepted for publication in Ap

Human capital and biological well-being : a first exploration of intragenerational and intergenerational effects in 20th-century Spain

El text s'ha presentat com a comunicació a l'European Population Conference 2010. Viena (Àustria), 1-4 de setembre de 2010.During the last five decades, Spain experienced a rapid transition towards high levels of development and well-being standards among Western societies. The specific contribution of human capital to the attainment of high development levels and its interaction with wellbeing and its biological components remains understudied. It is ignored to what extend economic growth and modernization would have rendered in terms of health without the improvement of educational status, particularly among mothers. It is also unknown to what extent differences in health status among Spanish regions and social classes are due to the human capital factor. In this paper it is aimed to explore the relationship between human capital formation and the biological wellbeing throughout the 20th century in Spain. The former will be approached by educational levels whereas cohort adult height will serve as a proxy of biological well-being. We will study both intra and intergenerational effects of human capital accumulation on the biological well-being of the Spanish population born between 1910 and 1976. A number of sociodemographic and socioeconomic characteristics will be used as control variables. The bulk of this work is based on microdata from the waves of the Spanish National Health Survey (ENSE) held between 1987 and 2006. Demographic analysis together with regression techniques form the core of the methodology.Durant les darreres cinc dècades, Espanya ha experimentat una ràpida transició cap a nivells de desenvolupament i benestar més alts. La contribució específica del capital humà a aquest procés i la seva interacció amb el benestar biològic és un aspecte encara poc investigat dins d'aquesta transició. En aquest sentit, desconeixem fins a quin punt el creixement econòmic espanyol hauria repercutit, en termes de salut, si no s'hagués donat, en paral·lel, una millora en els nivells de formació, particularment entre les mares. Es desconeix també el paper específic que ha jugat la formació del capital humà, en la configuració de les diferències de salut entre les regions espanyoles i entre les classes socials. En aquest treball s'explora, per a Espanya, la relació entre el capital humà i el benestar biològic de la població al llarg del segle XX,. El capital humà es troba a partir del nivell d'instrucció, mentre que pel benestar biològic s'utilitza l'alçada adulta de les generacions. Es plantegen dos nivells d'anàlisi: intrageneracional i intergeneracional, per a les cohorts nascudes entre 1910 i 1976, a partir de microdades de l'Enquesta Nacional de Salut (ENSE; edicions 1987-2006). Es combina l'anàlisi demogràfica amb l'anàlisi de regressió i s'introdueixen diverses variables sociodemogràfiques com a controladors de la relació abans esmentada.Durante las últimas cinco décadas, España ha experimentado una rápida transición hacia altos niveles de desarrollo y bienestar. La contribución específica del capital humano a este proceso así como su interacción con el bienestar biológico, es un aspecto aún poco investigado dentro de esa transición. En este sentido, se desconoce hasta qué punto el crecimiento económico español habría repercutido de igual forma, en términos de salud, sin una mejora en paralelo de los niveles de formación, particularmente entre las madres. Se desconoce también el papel específico de la formación del capital humano, en la configuración de las diferencias de salud entre las regiones españolas y las clases sociales. En este trabajo se explora la relación entre el capital humano y el bienestar biológico de la población a lo largo del siglo XX en España. El capital humano se deduce del nivel educativo mientras que para el bienestar biológico se utiliza la estatura adulta de las generaciones. Se plantean dos niveles de análisis: intrageneracional e intergeneracional para las cohortes nacidas entre 1910 y 1976 a partir de microdatos de la Encuesta Nacional de Salud (ENSE; ediciones 1987-2006). Se combina el análisis demográfico con el análisis de regresión y se introducen diversas variables sociodemográficas como controladores de la relación mencionada

OBSERVABILITY AND OBSERVERS IN A FOOD WEB

The problem of the possibility to recover the time-dependent state of a whole population system out of the observation of certain components has been studied in earlier publications, in terms of the observability concept of mathematical systems theory. In the present note a method is proposed to effectively calculate the state process. For an illustration an observer system for a simple food web is numerically constructed

Observer design for open and closed trophic chains

Monitoring of ecological systems is one of the major issues in ecosystem research. The concepts and methodology of mathematical systems theory provide useful tools to face this problem. In many cases, state monitoring of a complex ecological system consists in observation (measurement) of certain state variables, and the whole state process has to be determined from the observed data. The solution proposed in the paper is the design of an observer system, which makes it possible to approximately recover the state process from its partial observation. Such systems-theoretical approach has been applied before by the authors to Lotka–Volterra type population systems. In the present paper this methodology is extended to a non-Lotka–Volterra type trophic chain of resource–producer–primary consumer type and numerical examples for different observation situations are also presented

Recent Developments in Monitoring of Complex Population Systems

The paper is an update of two earlier review papers concerning the application of the methodology of mathematical systems theory to population ecology, a research line initiated two decades ago. At the beginning the research was con- centrated on basic qualitative properties of ecological models, such as observability and controllability. Observability is closely related to the monitoring problem of ecosystems, while controllability concerns both sustainable harvesting of population systems and equilibrium control of such systems, which is a major concern of conservation biology. For population system, observability means that, e.g. from partial observation of the system (observing only certain indica- tor species), in principle the whole state process can be recovered. Recently, for different ecosystems, the so-called ob- server systems (or state estimators) have been constructed that enable us to effectively estimate the whole state process from the observation. This technique offers an efficient methodology for monitoring of complex ecosystems (including spatially and stage-structured population systems). In this way, from the observation of a few indicator species the state of the whole complex system can be monitored, in particular certain abiotic effects such as environmental contamina- tion can be identified. In this review, with simple and transparent examples, three topics illustrate the recent develop- ments in monitoring methodology of ecological systems: stock estimation of a fish population with reserve area; and observer construction for two vertically structured population systems (verticum-type systems): a four-level ecological chain and a stage-structured fishery model with reserve area

Iterative scheme for the observation of a competitive Lotka-Volterra system

In this work, in terms of the model parameters, suffcient conditions are established to construct a sequence of approximate observers for a two-species competitive Lotka-Volterra system. This iterative approach makes it possible to localize the solution of the system, and reveal its long-term behaviour. The main results are also illustrated by numerical simulations

Equilibrium, observability and controllability in selection-mutation models

In this paper we shortly discuss the problem of the equilibrium in the well-known Fisher type selection-model, also providing a formula for particular three-allele models. The considered continuous-time dynamics is a known extension of the classical model of natural selection given by Fisher. We also extend the existing investigation of the observability of Fisher’s model to the case when another evolutionary factor, mutation is also present. Moreover, we prove a result of technical character, which makes it possible to apply the methodology of nonlinear systems with invariant manifold, to models of artificial selection. For an illustration, a class of three-allele systems is presented in which the controllability into equilibrium is guaranteed without any condition on the biological parameters