Central limit theorems for four new types of U-designs

Orthogonal array (OA)-based Latin hypercube designs, also called U-designs, have been popularly adopted in designing a computer experiment. Nested U-designs, sliced U-designs, strong OA-based U-designs and correlation controlled U-designs are four types of extensions of U-designs for different applications in computer experiments. Their elaborate multi-layer structure or multi-dimensional uniformity, which makes them desirable for different applications, brings difficulty in analysing the related statistical properties. In this paper, we derive central limit theorems for these four types of designs by introducing a newly constructed discrete function. It is shown that the means of the four samples generated from these four types of designs asymptotically follow the same normal distribution. These results are useful in assessing the confidence intervals of the gross mean. Two examples are presented to illustrate the closeness of the simulated density plots to the corresponding normal distributions.     

D-1-Partially efficiency-balance designs with at most two efficiency classes

A wide class of block designs admitting a simple analysis has been considered. The statistical properties of such designs have been indicated and the problems relating to their characterization and construction have been investigated.     

Robustness group divisible designs

Robustness of group divisible (GD) designs is investigated, when one block is lost, in terms of efficiency of the residual design. The exact evaluation of the efficiency can be made for singular GD and semi-regular GD designs as ell as regular GD designs with λ₁ = 0. In a regular GD design with λ₁ > 0, the efficiency may depend upon the lost block and sharp upper and lower bounds on the efficiency are presented. The investigation shows that GD designs are fairly robust in terms of efficiency. As a special case, we can also show the robustness of balanced incomplete block design when one block is lost.     

A new response-adaptive design for continuous treatment responses for phase III clinical trials

A new response-adaptive design, applicable for general class of continuous response distributions, is proposed. The allocation design is studied both theoretically and numerically and compared with some existing procedures. The applicability of the proposed procedure is also illustrated using real life data sets.     

On fourth order rotatable designs

Recently, Draper and Herzberg posed some open problems on fourth order rotatable designs. It has been attempted to settle these open problems.     

Queer Questions

Abstract

As rights claims on the basis of sexual orientation and gender identity occupy an increasingly prominent place in international politics, it seems clear that the long-running Woman Question has been supplemented by a set of variously articulated “queer questions.” Drawing on postcolonial, feminist and queer theory, and readings of queer literary and cinematic texts from India and Iran, this article explores moments of resonance, intersection and tension between the Woman Question and queer questions. It argues, first, that contemporary queer questions echo the preoccupations of the Woman Question even as they are uncannily prefigured by it; second, that these questions have been mutually disruptive of one another, so that queer questions are not simply a rerun of the Woman Question; and third, that differences between these questions are problematically flattened out in projections of shared futurity articulated in the abstract universality of “human rights.” Navigating the shared pasts, fraught presents and imagined futures of Woman and queer questions, the article brings queer critiques of temporality to bear on the concerns of postcolonial queer activism. It elucidates opportunities and challenges for alliance between the subjectivities interpellated by these various questions. In addition, it asks how the proliferation of new subjectivities under the sign of “queer” troubles notions of universal human rights.     

Data-dependent probability matching priors for highest posterior density and equal-tailed two-sided regions based on empirical-type likelihoods

We consider a very general class of empirical-type likelihoods which includes the usual empirical likelihood and all its major variants proposed in the literature. It is known that none of these likelihoods admits a data-free probability matching prior for the highest posterior density region. We develop necessary higher order asymptotics to show that at least for the usual empirical likelihood this difficulty can be resolved if data-dependent priors are entertained. A related problem concerning the equal-tailed two-sided posterior credible region is also investigated. A simulation study is seen to lend support to the theoretical results.     

A new test for decreasing mean residual lifetimes

The mean residual life of a non negative random variable X with a finite mean is defined by M(t) = E[X ? t|X > t] for t ? 0. One model of aging is the decreasing mean residual life (DMRL): M is decreasing (non increasing) in time. It vastly generalizes the more stringent model of increasing failure rate (IFR). The exponential distribution lies at the boundary of both of these classes. There is a large literature on testing exponentiality against DMRL alternatives which are all of the integral type. Because most parametric families of DMRL distributions are IFR, their relative merits have been compared only at some IFR alternatives. We introduce a new Kolmogorov–Smirnov type sup-test and derive its asymptotic properties. We compare the powers of this test with some integral tests by simulations using a class of DMRL, but not IFR alternatives, as well as some popular IFR alternatives. The results show that the sup-test is much more powerful than the integral tests in all cases.     

A multi-treatment two stage adaptive allocation for survival outcomes

A multi-treatment two stage adaptive allocation design is developed for survival responses. Assuming noninformative random censoring, asymptotic p values of relevant tests of equality of treatment effects are used to derive the assignment probability of incoming second stage subjects. Several ethical and inferential criteria of the design are studied, and are compared with those of an existing competitor. Applicability and performance of the proposed design are also illustrated using a data arising from a real clinical trial.