TY - BOOK AU - Rana Nabil Salah Eldeen Abdelaziz AU - Abdalla A. Abdelghaly , AU - Hanan M. Aly , TI - Applying the copula theory on accelerated life test under censoring / PY - 2019/// CY - Cairo : PB - Rana Nabil Salah Eldeen Abdelaziz , KW - Accelerated Life Testing KW - Log Linear Model KW - Step Stress Accelerated Life Testing N1 - Thesis (Ph.D.) - Cairo University - Faculty of Economics and Political Science - Department of Statistics; Issued also as CD N2 - Models with copulas have become increasingly popular for modeling multivariate data.The copula is a function that links the multivariate distributions to their one-dimensional marginal distributions. It is capable of describing the dependence structure between vari- ables. An important field of reliability in which the copula approach could be applied, is the accelerated life testing (ALT). In ALT, the test products are run at higher than usual levels of stress for shortening the life of products. Accelerated testing consists of a variety of test methods for shortening the life of products or hastening the degradation of their perfor- mance. The aim of such testing is to quickly obtain data which are properly modeled and analyzed, and yield desired information on product life or performance under normal use. Such testing saves much time and money. When the product fails because of one of many possible failure modes, it is said that we have competing failures which may react with each other. Moreover, accelerated life tests (ALTs) usually involve experimental protocols that lead to a grouped structure among observations.Thus, it is important to consider the group effect in the analysis to get accurate results ER -