This paper considers the analysis of Weibull distributed lifetime data observed under Type II progressive censoring with random removals, where the number of units removed at each failure time follows a binomial distribution. Maximum likelihood estimators of the parameters and their asymptotic variances are derived. The expected time required to complete the life test under this censoring scheme is investigated.

This paper considers the estimation problem when lifetimes are Weibull distributed and are collected under a Type-I1 progressive censoring with random removals, where the number of units removed at each failure time follows a uniform discrete distribution. The expected time of this censoring plan is discussed and compared numerically to that under a Type I1 censoring without removal. Maximum likelihood estimator of the parameters and their asymptotic variances are derived.

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We study approximate algorithms for placing a set of documents into M distributed Web servers in this paper. We define the load of a server to be the summation of loads induced by all documents stored. The size of a server is defined in a similar manner. We propose five algorithms. Algorithm 1 balances the loads and sizes of the servers by limiting the loads to k l and the sizes to k s times their optimal values, where 1 klÀ1 þ 1 ksÀ1 1. This result improves the bounds on load and size of servers in [10]. Algorithm 2 further reduces the load bound on each server by using partial document replication, and Algorithm 3 by sorting. Algorithm 4 employs both partial replication and sorting. Last, without using sorting and replication, we give Algorithm 5 for the dynamic placement at the cost of a factor Oðlog MÞ in the time-complexity.

This paper concerns techniques for detection of a potential outlier or extreme observation in a bioavailability/bioequivalence study. A bioavailability analysis that includes possible outlying values may affect the decision on bioequivalence. We consider a general crossover model that takes into account period and formulation effects. We derive two test procedures, the likelihood distance and the estimates distance, to detect potential outliers. We show that the two procedures relate to a chi-square distribution with three degrees of freedom. The main purpose of this paper is to exhibit and discuss these two general approaches of outliers detection in the context of a bioavailability/bioequivalence study. To illustrate these approaches, we use data from three-way crossover experiment in the pharmaceutical industry that concerned the comparison of the bioavailability of two test formulations and a standard (reference) formulation of a drug. This example demonstrates the influence of an outlying value in the study of bioequivalence.