In this paper we provide evidence that financial option markets for equity indices give rise to non-trivial dependency structures between its constituents. Thus, if the individual constituent distributions of an equity index are inferred from the single-stock option markets and combined via a Gaussian copula, for example, one fails to explain the steepness of the observed volatility skew of the...

Heon-Jae Jeong1*, Minji Kim2, Eun Ae An3, So Yeon Kim4 and Byung Joo Song4 1Department of Health Policy and Management, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, USA 2Annenberg School for Communication, University of Pennsylvania, USA 3Leadership Development Division, The Catholic Education Foundation, Korea 4Performance Improvement Team, Seoul St. Mary’s Hospit...

In this note we discuss model fit evaluation for the Latent Class Analysis (LCA) model under complex sampling. Suppose that for the i− individual in the sample we observe r categorical/discrete variables Ui1, ..., Uir. Suppose that for individual i there exist one unobserved categorical variable Ci, called the latent class variable. The LCA model is described by the following equations P (Uij =...

Résumé. Dans ce papier nous proposons PLCM, un algorithme parallèle de découverte d’itemsets fréquents fermés basé sur l’algorithme LCM, reconnu comme l’algorithme séquentiel le plus efficace pour cette tâche. Nous présentons aussi une interface de parallélisme à la fois simple et puissante basée sur la notion de Tuple Space, qui permet d’avoir une bonne répartition dynamique du travail. Grâce ...

This cross-national study investigates the perception of the impact of students’ relationships towards teachers and peers on scholastic motivation in a total sample of 1477 seventh and eighth grade German (N1⁄4 1088) and Canadian (N1⁄4 389) secondary school students. By applying Multigroup Confirmatory Latent Class Analysis in Mplus we confirmed four different motivation types: (1) teacher-depe...

In this paper we deal with the problem of identifying a valid way to characterize heterogeneity in the analysis of customer satisfaction observing the phenomenon through a new perspective. In the literature, the variability of a Customer Satisfaction index is measured by the standard deviation or the coefficient of variation. In this way, heterogeneity among customers may be masked. To overcome...

....................................................................Page 6 Introduction................................................................Pages 7-11 Materials and Methods...................................................Pages 12-17 Results......................................................................Pages 18-31 Discussion.......................................................

This paper describes a method of explorative data analysis which allows to detect logical implications between items of a dichotomous questionnaire or test. These logical dependencies are organized to form a hierarchical structure (quasi-order) on the items. Our analysis method, which is called Inductive Item Tree Analysis, can be seen as a method of Boolean analysis. We discuss the relation of...

This paper outlines the combination of two prominent theories of social life: 1) modernization theory and 2) W.I. Thomas’ theorem that people’s perceptions have real consequences. It then documents the extent to which the complex idea of modernization and development has cemented itself in the minds of ordinary people as a model of how the world works. I employ latent class analysis and use 200...

Received March 13, 2007 Abstract For any positive integer n, the Smarandache LCM dual function SL∗(n) is defined as the greatest positive integer k such that [1, 2, · · · , k] divides n. The main purpose of this paper is using the elementary method to study the calculating problem of a Dirichlet series involving the Smarandache LCM dual function SL∗(n) and the mean value distribution property o...