Doubly Robust Sure Screening for Elliptical Copula Regression Model

Regression analysis has always been a hot research topic in statistics. We propose a very flexible semi-parametric regression model called Elliptical Copula Regression (ECR) model, which covers a large class of linear and nonlinear regression models such as additive regression model,single index model. Besides, ECR model can capture the heavy-tail characteristic and tail dependence between variables, thus it could be widely applied in many areas such as econometrics and finance. In this paper we mainly focus on the feature screening problem for ECR model in ultra-high dimensional setting. We propose a doubly robust sure screening procedure for ECR model, in which two types of correlation coefficient are involved: Kendall tau correlation and Canonical correlation. Theoretical analysis shows that the procedure enjoys sure screening property, i.e., with probability tending to 1, the screening procedure selects out all important variables and substantially reduces the dimensionality to a moderate size against the sample size. Thorough numerical studies are conducted to illustrate its advantage over existing sure independence screening methods and thus it can be used as a safe replacement of the existing procedures in practice. At last, the proposed procedure is applied on a gene-expression real data set to show its empirical usefulness.Comment: 22 pages, 2 figure

El entendimiento sobre el Tratado de Libre Comercio entre China y Chile

Las relaciones chino-chilenas se encuentran actualmente en la mejor época de su historia, y al mismo tiempo, enfrentan una oportunidad importante para profundizarlas. Teniendo presente la situación del mundo y de la Cuenca del Pacífico, así como las relaciones chino-chilenas, ambos países resolvieron que era importante establecer mecanismos económico-comerciales bilaterales, y en junio de 2002, la República Popular China propuso a Chile iniciar negociaciones orientadas a suscribir un tratado de libre comercio, las que se formalizaron en noviembre de 2004, durante la cumbre de APEC. Tras 5 rondas de negociaciones, el 18 de noviembre de 2005 se firmó oficialmente el Tratado de Libre Comercio entre ambos países. Este importante paso puede reforzarse en el futuro aprovechando la creciente globalización económica, los avances de la ciencia y de la tecnología, las nuevas facilidades de transferencia de información y de comunicaciones y transporte, y afianzando el intercambio político y entre diversos sectores sociales de ambos países, a fin de profundizar el conocimiento y el entendimiento recíprocos. Para profundizar aún más esta relación se hace por tanto necesario, mantener intercambios entre las esferas políticas de ambos países; reforzar el intercambio entre los diversos sectores sociales; iniciar y completar cuanto antes las negociaciones sobre servicios e inversión al mismo tiempo, hay que reglamentar las relaciones económico-comerciales bilaterales en el marco del tratado de libre comercio, y reforzar la cooperación bilateral dirigida a terceros países, para que los efectos de estas se amplíen hacia el resto de los países de Sudamérica y Asia; explorar y probar nuevos modelos y formas de cooperación chino-chilena; y explotar las potencialidades de las empresas privadas de China, a fin de que participen en los esfuerzos por afianzar relaciones mutuas, incluso en las microempresas y las empresas pequeñas, medianas y grandes

Demonstration of Geometric Landau-Zener Interferometry in a Superconducting Qubit

Geometric quantum manipulation and Landau-Zener interferometry have been separately explored in many quantum systems. In this Letter, we combine these two approaches to study the dynamics of a superconducting phase qubit. We experimentally demonstrate Landau-Zener interferometry based on the pure geometric phases in this solid-state qubit. We observe the interference caused by a pure geometric phase accumulated in the evolution between two consecutive Landau-Zener transitions, while the dynamical phase is canceled out by a spin-echo pulse. The full controllability of the qubit state as a function of the intrinsically robust geometric phase provides a promising approach for quantum state manipulation.Comment: 5 pages + 3 pages supplemental Materia

A SPLIT Model for Extraction of Subpixel Impervious Surface Information

This paper introduces a Subpixel Proportional Land cover Information Transformation (SPLIT) model to extract proportions of impervious surfaces in urban and suburban areas. High spatial resolution airborne Digital Multispectral Videography (DMSV) data provided subpixel information for Landsat TM data. The SPLIT model employed a Modularized Artificial Neural Network (MANN) to integrate multi-sensor remote sensing data and to extract proportions of impervious surfaces and other types of land cover within TM pixels. Through a control unit, the MANN was able to decompose a complex task into multiple subtasks by using a group of sub-networks. The SPLIT model identified spectral relations between TM pixel values and the corresponding DMSV subpixel patterns. The established relationship allows extrapolation of the SPLIT model to the areas beyond DMSV data coverage. We applied five intervals, i.e., \u3c20 percent, 21 to 40 percent, 41 to 60 percent, 61 to 80 percent, and \u3e81 percent, to map the subpixel proportions of land cover types. We extrapolated the SPLIT model from training sites that have both TM and DMSV coverage into the entire DuPage County with TM data as the input. The extrapolation received 82.9 percent overall accuracy for the extracted proportions of urban impervious surface

A comparative study of the Chinese characters in the Graded list and the EBCL list

This study scrutinizes the Chinese characters in two reference works compiled as part of two projects: the Graded list and the EBCL list. Situated in the character-based theory, the characters compiled in both are examined in depth from the perspective of character complexity, character structure, semantic and phonetic radical transparency, frequency of character and frequency of word formation. The results show that the two lists share similarities in terms of distribution of characters of different structures, level of semantic radical transparency, and frequencies of character and word formation. The character complexity of the Graded list is higher than that of the EBCL, while the level of phonetic radical transparency of the Graded list is lower than that of the EBCL list. With the Graded list, the high demands of character learning need to be borne in mind; this is due to the visual load of character complexity and the pronunciation information provided in phonetic radicals. Against a backdrop of increasing demand for CFL pedagogical materials, the differences and similarities between the two lists analysed and discussed in this study contribute to their pedagogical applications in teaching and learning Chinese characters