¿Rankings educativos : indicadores de resultados o de diferencias socioeconómicas?

Resumen tomado de la publicación

Los rankings universitarios : estado de la cuestión y posibles aplicaciones al caso español.

Resumen tomado de la publicación

Rankings internacionales y calidad de los sistemas universitarios.

Resumen tomado de la publicación. Monográfico con el título: Tiempos de cambio universitario en Europa

Gu??a de buenas pr??cticas para la participaci??n de las universidades espa??olas en los rankings internacionales

Resumen basado en el de la publicaci??n

Rankings internacionales : metodolog??a y posicionamiento de las universidades espa??olas

Se analiza un grupo de rankings internacionales, los denominados League Tables (ARWU, THE, QS); un segundo grupo de rankings centrados en resultados de investigaci??n (CWTS, HEEACT, SCIMAGO Institutions Ranking, URAP); y un tercer grupo de rankings internacionales basados en varios indicadores sin intenci??n de crear tablas ordenadas de instituciones (CHE, UMultirank, U-Ranking).

An??lisis de los datos de las universidades espa??olas en los rankings internacionales

Se analiza la informaci??n con la que los rankings globales ( Arwu, THE y QS, SCIMAGO; CWTS, HEEACT y CHE; U-Multirank y U-Ranking.) elaboran sus indicadores as?? como las puntuaciones y posiciones resultantes obtenidas por las universidades espa??olas. A partir de una solicitud de participaci??n canalizada desde el Ministerio de Educaci??n, Cultura y Deporte a las 72 universidades espa??olas, p??blicas y privadas que presentan datos de investigaci??n en el Observatorio IUNE, se obtienen y analizan los cuestionarios e informes de datos para la participaci??n en los rankings de 2013 de 19 universidades. A continuaci??n, se describen los datos solicitados a las universidades por los tres rankings, que est??n referidos a profesorado, estudiantes, t??tulos y datos econ??micos. Por ??ltimo, se detallan los datos que cada universidad participante en el estudio aporta a los rankings y con los que ??stos obtienen sus indicadores, mostr??ndose los perfiles de cada una de ellas. Tambi??n se muestra el nivel de concordancia entre los datos solicitados y los aportados.

Competir o compartir? : reflexionant sobre els efectes dels rankings en els sistemes educatius

Resumen basado en el de la publicaci??n

La literatura cient??fica sobre rankings universitarios : una revisi??n sistem??tica

Resumen basado en el de la publicaci??n

Medical image registration based on random line sampling

One of the key aspects in 3D-image registration is the computation of the joint intensity histogram. We propose a new approach to compute this histogram using uniformly distributed random lines to sample stochastically the overlapping volume between two 3D-images. The intensity values are captured from the lines at evenly spaced positions, taking an initial random offset different for each line. This method provides us with an accurate, robust and fast mutual information-based registration. The interpolation effects are drastically reduced, due to the stochastic nature of the line generation, and the alignment process is also accelerated. The results obtained show a better performance of the introduced method than the classic computation of the joint histogram

Random walk radiosity with generalized absorption probabilities

The author studies random walk estimators for radiosity with generalized absorption probabilities. That is, a path will either die or survive on a patch according to an arbitrary probability. The estimators studied so far, the infinite path length estimator and finite path length one, can be considered as particular cases. Practical applications of the random walks with generalized probabilities are given. A necessary and sufficient condition for the existence of the variance is given, together with heuristics to be used in practical cases. The optimal probabilities are also found for the case when one is interested in the whole scene, and are equal to the reflectivities

Error and complexity of random walk Monte Carlo radiosity

The author studies the error and complexity of the discrete random walk Monte Carlo technique for radiosity, using both the shooting and gathering methods. The author shows that the shooting method exhibits a lower complexity than the gathering one, and under some constraints, it has a linear complexity. This is an improvement over a previous result that pointed to an O(n log n) complexity. The author gives and compares three unbiased estimators for each method, and obtains closed forms and bounds for their variances. The author also bounds the expected value of the mean square error (MSE). Some of the results obtained are also shown

Analysis and Simulation of Transverse Random Fracture of Long Fibre Reinforced Composites

La present tesi proposa una metodología per a la simulació probabilística de la fallada de la matriu en materials compòsits reforçats amb fibres de carboni, basant-se en l'anàlisi de la distribució aleatòria de les fibres. En els primers capítols es revisa l'estat de l'art sobre modelització matemàtica de materials aleatoris, càlcul de propietats efectives i criteris de fallada transversal en materials compòsits. El primer pas en la metodologia proposada és la definició de la determinació del tamany mínim d'un Element de Volum Representatiu Estadístic (SRVE) . Aquesta determinació es du a terme analitzant el volum de fibra, les propietats elàstiques efectives, la condició de Hill, els estadístics de les components de tensió i defromació, la funció de densitat de probabilitat i les funcions estadístiques de distància entre fibres de models d'elements de la microestructura, de diferent tamany. Un cop s'ha determinat aquest tamany mínim, es comparen un model periòdic i un model aleatori, per constatar la magnitud de les diferències que s'hi observen. Es defineix, també, una metodologia per a l'anàlisi estadístic de la distribució de la fibra en el compòsit, a partir d'imatges digitals de la secció transversal. Aquest anàlisi s'aplica a quatre materials diferents. Finalment, es proposa un mètode computacional de dues escales per a simular la fallada transversal de làmines unidireccionals, que permet obtenir funcions de densitat de probabilitat per a les variables mecàniques. Es descriuen algunes aplicacions i possibilitats d'aquest mètode i es comparen els resultats obtinguts de la simulació amb valors experimentals.

Nem tudo o que conta em educação é mensurável ou comparável. Crítica à accountability baseada em testes estandardizados e rankings escolares

O conceito de accountability é, em geral, polissémico e denso. Contudo, eu pretendo, neste texto, mencionar apenas alguns dos aspectos da sua contextualização ampla em termos teórico-conceptuais. Associo o conceito de accountability a três dimensões articuláveis: avaliação, prestação de contas e responsabilização. Depois, analiso algumas das relações entre avaliação e accountability tendo como pretexto os testes estandardizados, os exames nacionais e os rankings. Finalmente, concluo que a accountability baseada apenas nestes procedimentos é uma forma parcelar, incompleta e redutora face à complexidade e pluralidade dos objectivos, missões e funções da educação escolar.

Patch Scale Nest-Site Selection by Marbled Murrelets (Brachyramphus marmoratus)

The Marbled Murrelet (Brachyramphus marmoratus) is a threatened alcid that nests almost exclusively in old-growth forests along the Pacific coast of North America. Nesting habitat has significant economic importance. Murrelet nests are extremely difficult and costly to find, which adds uncertainty to management and conservation planning. Models based on air photo interpretation of forest cover maps or assessments by low-level helicopter flights are currently used to rank presumed Marbled Murrelet nesting habitat quality in British Columbia. These rankings are assumed to correlate with nest usage and murrelet breeding productivity. Our goal was to find the models that best predict Marbled Murrelet nesting habitat in the ground-accessible portion of the two regions studied. We generated Resource Selection Functions (RSF) using logistic regression models of ground-based forest stand variables gathered at plots around 64 nests, located using radio-telemetry, versus 82 random habitat plots. The RSF scores are proportional to the probability of nests occurring in a forest patch. The best models differed somewhat between the two regions, but include both ground variables at the patch scale (0.2-2.0 ha), such as platform tree density, height and trunk diameter of canopy trees and canopy complexity, and landscape scale variables such as elevation, aspect, and slope. Collecting ground-based habitat selection data would not be cost-effective for widespread use in forestry management; air photo interpretation and low-level aerial surveys are much more efficient methods for ranking habitat suitability on a landscape scale. This study provides one method for ground-truthing the remote methods, an essential step made possible using the numerical RSF scores generated herein.