Statistical pattern classification methods based on data-random graphs were introduced recently. In this approach, a random directed graph is constructed from the data using the relative positions of the data points from various classes. Different random graphs result from different definitions of the proximity region associated with each data point and different graph statistics can be employe...

A family of maximum mean discrepancy (MMD) kernel two-sample tests is introduced. Members of the test family are called Block-tests or B-tests, since the test statistic is an average over MMDs computed on subsets of the samples. The choice of block size allows control over the tradeoff between test power and computation time. In this respect, the B-test family combines favorable properties of p...

Kendall and Gehan estimating functions are used to estimate the regression parameter in accelerated failure time (AFT) model with censored observations. The accelerated failure time model is the preferred survival analysis method because it maintains a consistent association between the covariate and the survival time. The jackknife empirical likelihood method is used because it overcomes compu...

The use of data-random graphs in statistical testing of spatial patterns is introduced recently. In this approach, a random directed graph is constructed from the data using the relative positions of the points from various classes. Different random graphs result from different definitions of the proximity region associated with each data point and different graph statistics can be employed for...

In this article, new moment inequalities are derived for new renewal better than used (NRBU) and renewal new better than used (RNBU) classes of life distributions demonstrateing that if the mean life is finite for any of them, then all higher order moments exist. Next, based on these inequalities, new testing procedures for testing exponentiality against any one of the above classes are introdu...

Rank regression is a highly-efficient and robust approach to estimate regression coefficients and to make inference in the presence of outlying survival times. Heller (2007) developed a smoothed weighted rank regression function, which is used to estimate the regression parameter vector in an accelerated failure time model with right censored data. This function can be expressed as a U -statist...

This study was designed to elucidate the effect of ascorbic acid on salivary total antioxidant capacity in smokers. In this single blind crossover clinical trial, the whole unstimulated saliva of 30 smokers, who were randomly divided into two groups, was collected. In the first phase after the saliva collection, one group of patients took 500 mg of vitamin C powder, for 3 weeks. Then, saliva of...

The bootstrap is a popular and useful tool for estimating the asymptotic variance of complicated estimators. Ironically, the fact that the estimators are complicated can make the standard bootstrap computationally burdensome because it requires repeated re-calculation of the estimator. In this paper, we propose a method which is specific to extremum estimators based on U -statistics. The contri...