Equivariant estimation for the parameters of location-scale multivariate exponential models and its application in reliability analysis

ABSTRACT

By considering an absolutely continuous location-scale multivariate exponential model (Weier and Basu, 1980), we obtain minimum risk equivariant estimator(s) of the parameter(s). Given a location-scale multivariate exponential random vector, it is shown that the normalized spacings associated with the random vector are independent standard exponential. The distribution of the complete sufficient statistic is derived. We derive the performance measures of standby, parallel, and series systems and also obtain the minimum risk equivariant estimator of the mean time before failure of the three systems. Some of the results of this article are extensions of those of Chandrasekar and Sajesh (2010).     

Arab-American male identity negotiations: caught in the crossroads of ethnicity,religion, nationality and current contexts

We examine how the identities of male adolescents of Arab descent (ArD) relate to their current physical and phenomenological contexts and to the negative fallout from recent ethnicity-related political events. Seventy-seven ArD adolescents in seven United States middle schools with varying proportions of ArD students participated in focus-group interviews. Qualitative analysis provides evidence that adolescents' social identities depended on complex combinations of personal, situational, and contextual factors. Findings extend Spencer's PVEST theory, demonstrating that the salience of adolescents' national, pan-Arab, hyphenated Arab-American, or assimilated American identity stems from phenomenological experiences within their current context and from the cognitive processes and associated affects of their prior experiences in other proximal and distal contexts.