Pautas recientes de la movilidad laboral entre las provincias españolas. Periodo 2001-2006

En el trabajo tratamos de caracterizar la movilidad espacial existente en el mercado laboral español, tomando como referencia lo sucedido en el periodo comprendido entre los años 2001 a 2006. Para ello utilizamos datos sobre contratación producidos por el Instituto Nacional de Empleo. El objetivo que inicialmente nos proponemos es caracterizar la estructura espacial que subyace en los datos relativos a migración contratada. El análisis lo ampliamos introduciendo cierto detalle sectorial y sociodemográfico, en busca de singularidades y aspectos de interés. Sin embargo, la estructura espacial que encontramos es débil por lo que, en la segunda parte del trabajo, avanzamos hacia un modelo panel de tipo dinámico. Esta solución nos permite combinar la dimensión espacial, que da soporte físico a los datos, con la secuencia temporal que subyace en los flujos

Optimization techniques in respiratory control system models

One of the most complex physiological systems whose modeling is still an open study is the respiratory control system where different models have been proposed based on the criterion of minimizing the work of breathing (WOB). The aim of this study is twofold: to compare two known models of the respiratory control system which set the breathing pattern based on quantifying the respiratory work; and to assess the influence of using direct-search or evolutionary optimization algorithms on adjustment of model parameters. This study was carried out using experimental data from a group of healthy volunteers under CO2 incremental inhalation, which were used to adjust the model parameters and to evaluate how much the equations of WOB follow a real breathing pattern. This breathing pattern was characterized by the following variables: tidal volume, inspiratory and expiratory time duration and total minute ventilation. Different optimization algorithms were considered to determine the most appropriate model from physiological viewpoint. Algorithms were used for a double optimization: firstly, to minimize the WOB and secondly to adjust model parameters. The performance of optimization algorithms was also evaluated in terms of convergence rate, solution accuracy and precision. Results showed strong differences in the performance of optimization algorithms according to constraints and topological features of the function to be optimized. In breathing pattern optimization, the sequential quadratic programming technique (SQP) showed the best performance and convergence speed when respiratory work was low. In addition, SQP allowed to implement multiple non-linear constraints through mathematical expressions in the easiest way. Regarding parameter adjustment of the model to experimental data, the evolutionary strategy with covariance matrix and adaptation (CMA-ES) provided the best quality solutions with fast convergence and the best accuracy and precision in both models. CMAES reached the best adjustment because of its good performance on noise and multi-peaked fitness functions. Although one of the studied models has been much more commonly used to simulate respiratory response to CO2 inhalation, results showed that an alternative model has a more appropriate cost function to minimize WOB from a physiological viewpoint according to experimental data.Postprint (author's final draft

Bayesian networks applied to credit scoring problems: A practical application

En este artículo se aborda la forma de construir un clasificador eficiente a través de redes bayesianas utilizadas en la minería de datos y cuya finalidad es conseguir más precisión que otros modelos empleados en los problemas de credit scoring. El enfoque bayesiano, basado en modelos de probabilidad, emplea la teoría de la decisión para el análisis del riesgo eligiendo en cada situación que se presenta la acción que maximiza la utilidad esperada. Usando una muestra de datos bancarios reales se concluye la superior capacidad predictiva de estos modelos respecto a los resultados obtenidos por otros métodos estadísticos paramétricos y no paramétricosThis paper analyses how to build an efficient classifier across Bayesians networks usedin data mining. The purpose of using the Bayesian model is to improve credit scoring accuracy. The Bayesian approach, based on probability models, analyses risk by using the decision theory, yielding as a solution that action that maximizes the expected utility. Expert assessment maybe included in the model. To show the superiority of the Bayesian approach, results obtained for real bank data are compared with those obtained with alternative parametric and non-parametric model

Approaching the environmental rationale of extractivism in an afro-descendant community from the colombian pacific region

Dado que el uso y transformación del territorio en el Pacífico colombiano se ha realizado a través de una serie de prácticas y lógicas ancestrales que empiezan a transformarse desde finales del siglo XX, a través del empleo de la observación participante, este artículo describe las prácticas extractivas en el Consejo Comunitario de San Marcos (Buenaventura, Colombia) a inicios del siglo XXI, buscando presentar una aproximación a la racionalidad ambiental asociada, que orienta las acciones. Se concluye que la orientación hacia el mercado o el autoabastecimiento de las actividades extractivas en San Marcos y la escala de la intervención asociada, permiten dilucidar dos racionalidades ambientales en conflicto: la depredadora asociada a la presión de la modernidad capitalista y la alterna asociada a la cosmovisión y concepción afrocolombiana de la naturaleza.Since the use and transformation of the territory in the Colombian Pacific Region was conducted through a series of ancestral practices and rationales that have started changing since the late 20th century.by the use of participant observation, this article describes the extractive practices in the Community Council of San Marcos (Buenaventura, Colombia) at the beginning of the 21st century in order to present an approach to the associated environmental rationale that supports the actions. It is concluded that the market-oriented and the self-sufficiency orientation of extractive activities in San Marcos and the associated scale of intervention elucidate two environmental rationales in conflict: the predatory associated with the pressure of modern capitalism and the alternative associated to the Colombian Afrodescendent worldview and conception of nature

Imaging study of NGC 3372, the Carina nebula : I. UBVRIJHK photometry of Tr 14, Tr 15, Tr 16 and Car I

We present the results of a large-scale imaging photometric study of the stellar population in the northern part of NGC 3372 in the UBVRIJHK bands with a wavelength coverage from 0.33 to 2.5 μm. The observations were made at Las Campanas Observatory. The optical CCD mosaics cover an area approximately of 32 × 22 arcmin2 centred between the Tr 14 and Tr 16 clusters. The survey was extended to cover 12 × 12 arcmin2 at the location of Tr 15. Near-infrared NICMOS3 mosaics covering the areas occupied by these clusters were obtained in the JHK photometric bands. By means of star counts in V, the centres and sizes of each cluster were redetermined yielding: Tr 14 (r = 264 arcsec), Tr 15 (r = 320 arcsec) and Tr 16 (r = 320 arcsec). It was confirmed that Cr 232 is not a true cluster. Multicolour optical photometry was obtained for 4152 stars. Two colour and colour-magnitude diagrams are presented and analysed for each individual cluster and compared to those of the field. We confirm the widespread variations in the dust density and also in the dust size distribution leading to widely different values of AV and reddening laws towards Tr 14 and Tr 16. No spatial patterns were found for these variations. Spectroscopic parallaxes were computed and the results are consistent with all three clusters being at a similar distance from the Sun (〈d〉 = 2.7 kpc) but the data have shown very large scatter in both AV and d. Analyses of the extinction-corrected colour-magnitude diagrams suggest ages between 3 and 60 million years for the stars in Tr 15 and between less than 1 and 6 million years for Tr 14 and Tr 16. A small number of infrared-excess stars were found in Tr 16 and Tr 14 but not in Tr 15. The distribution of stars in Tr 14 seen in the near-infrared suggests that this cluster is partially embedded in a molecular cloud. This molecular cloud extends towards the west reaching its highest density, marked by a CO peak emission, some three arcmin to the south-west of the nucleus of Tr 14. The rich ultraviolet field created by the Tr 14 stars ionizes most of the visible H II region in its vicinity and most of the radio H II region Car I. Evidence is found of ionization fronts leading into the molecular cloud, which appears to be 'wrapping' the Tr 14 cluster. Deep JHK images of the Car I region reveal the presence of an embedded stellar population illuminating a large infrared reflection nebula. It includes at least one O9-B0 star associated with an ultracompact H II region. Nebulous 2.2 μm emission from three of the mid-infrared sources in the Tr 14 region is also found.Facultad de Ciencias Astronómicas y Geofísica