9,984 research outputs found
Empirical likelihood confidence intervals for complex sampling designs
We define an empirical likelihood approach which gives consistent design-based confidence intervals which can be calculated without the need of variance estimates, design effects, resampling, joint inclusion probabilities and linearization, even when the point estimator is not linear. It can be used to construct confidence intervals for a large class of sampling designs and estimators which are solutions of estimating equations. It can be used for means, regressions coefficients, quantiles, totals or counts even when the population size is unknown. It can be used with large sampling fractions and naturally includes calibration constraints. It can be viewed as an extension of the empirical likelihood approach to complex survey data. This approach is computationally simpler than the pseudoempirical likelihood and the bootstrap approaches. The simulation study shows that the confidence interval proposed may give better coverages than the confidence intervals based on linearization, bootstrap and pseudoempirical likelihood. Our simulation study shows that, under complex sampling designs, standard confidence intervals based on normality may have poor coverages, because point estimators may not follow a normal sampling distribution and their variance estimators may be biased.<br/
SACY - a Search for Associations Containing Young stars
The scientific goal of the SACY (Search for Associations Containing
Young-stars) was to identify possible associations of stars younger than the
Pleiades Association among optical counterparts of the ROSAT X-ray bright
sources. High-resolution spectra for possible optical counterparts later than
G0 belonging to HIPPARCOS and/or TYCHO-2 catalogs were obtained in order to
assess both the youth and the spatial motion of each target. More than 1000
ROSAT sources were observed, covering a large area in the Southern Hemisphere.
The newly identified young stars present a patchy distribution in UVW and XYZ,
revealing the existence of huge nearby young associations. Here we present the
associations identified in this survey.Comment: 8 pages, 2 figures, to appear in the Proceedings of Open Issues in
Local Formation and Early Stellar Evolution, Ouro Preto, Brazi
Facetas del Miedo:: La piratería y la Gobernación de Yucatán (1565)
On November 26, 1565, the procurator of Yucatán, Joaquín Leguisamo, filed a report to expose the danger in which the province found itself due to the presence and plunder of French pirates. The report is analyzed with the objective of furnishing details of the piracy phenomenon and measures taken by Yucatán authorities to counter it. A cultural history of fear is invoked to address (1): the definition of privateering as a source of damages; (2) locations in the Gulf-Caribbean where piracy took place, its proximity to the Yucatán a cause for concern; and (3) vulnerability and insecurity, both arising from the fear of the Yucatán being lost to pirate assaults. These considerations allow us to assess the impact of piracy through the eyes of colonial authorities whose job it was the govern the province.El 26 de noviembre de 1565 el procurador de Yucatán, Joaquín Leguisamo, condujo la realización de una información para exponer el peligro en el que estaba la provincia gracias a la presencia y actividad de corsarios franceses. Nuestro propósito es analizar este documento para dar cuenta de los entrelazamientos suscitados entre el fenómeno de la piratería y la gobernación yucateca. Para ello, planteamos una historia cultural del miedo que atienda: la definición de corsario como origen de afectaciones; la ubicación de esa otredad peligrosa en el Golfo-Caribe y su cercanía a la península de Yucatán; las vulnerabilidades y un entorno de inseguridad, ambos procedentes del temor a la pérdida de Yucatán ante una invasión de corsarios. Estas dimensiones permiten un acercamiento tanto al impacto del fenómeno de la piratería en la provincia como las formas en que las autoridades coloniales dieron sentido a aquel
El aprendizaje cooperativo en el aula de inglés de 4º de Educación Primaria
El presente Trabajo de Fin de Grado nos da la oportunidad no solo de analizar el aprendizaje cooperativo que surge a raíz del trabajo cooperativo en el aula de inglés sino también ofrece una propuesta personal de intervención en el aula donde las actividades para trabajar son fundamentalmente grupos cooperativos.
En primer lugar hay que mencionar que este trabajo se ha hecho bajo la actual ley de educación, LOE, la cual recoge la enseñanza de una segunda lengua como es el inglés. En el marco teórico, definiremos que es el aprendizaje cooperativo y en que contextos surge. Para ello analizaremos los requisitos que hacen falta para que, de una actividad grupal, surja aprendizaje cooperativo. También nos centraremos en las ventajas y desventajas que puede haber a la hora de trabajar en grupos cooperativos. Investigaremos acerca de su origen, su situación actual y por qué ha resurgido el aprendizaje cooperativo de nuevo. Finalmente haremos un análisis sobre qué es y qué no es aprendizaje cooperativo.
En el marco práctico, se llevará a cabo una investigación cualitativa a partir de las ideas desarrolladas en el marco teórico. Por un lado se desarrollará una unidad didáctica, basada fundamentalmente en el trabajo por grupos cooperativos, a modo de propuesta personal de intervención educativa en el aula. Por otra parte se contrastarán opiniones acerca del trabajo cooperativo con otros docentes que imparten inglés en el segundo ciclo de educación primaria.
Asimismo se presentarán reflexiones y conclusiones finales en las que se puede ver la relación entre el tema analizado con aspectos fundamentales que los niños desarrollarán para poder adaptarse mejor a los cambiosGrado en Educación Primari
Progresa
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Political Science, 2007.Includes bibliographical references (leaves 190-202).Ever since Latin American economies collapsed in the 1980s and early 1990s, traditional redistributive programs began to coexist with new anti-poverty programs that usually took the form of conditional cash transfers (CCT). I examine the effects of the Mexican Education, Health, and Nutrition program (Progresa), the first and largest CCT implemented in the region, on electoral behavior. I argue that Progresa not only was substantially different from traditional clientelism, but that it challenged local monopolies on political power by increasing voter's income and giving recipients implicit and explicit information about its non-political nature. This weakening of monopolies, in turn, gave political parties incentives to compete for the votes of Progresa recipients. As a consequence, recipients increased their electoral participation, at least in the short term, and clientelism was irrevocably eroded. Despite the increased competition, however, recipients rewarded parties that proposed and retained Progresa. My understanding of Progresa's electoral effects is based on theory, field research on four villages, interviews with Progresa's designers and personnel, and analysis of media sources from 1996 until 2003. To test this argument, I use the Mexico 2000 Panel Study; aggregate data at the municipality level from 1997-2003; and to explicitly deal with the historic correlation between poverty, rural residence, and support for the seventy-year incumbent party, Institutional Revolutionary Party, I take advantage of the fact that early assignment of program benefits included a randomized component originally designed to evaluate the program effects on schooling and health.by Ana Lorena De La O Torres.Ph.D
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