On a Mixed-Type Randomized Rule for Selecting Superior Binomial Models

We propose a new class of selection rules for selecting superior models from finite Binomial models. This new class of rules extends the classes of classical rules and shows its superiority to the classical selection rules by some Monte Carlo results. This new class of rules is easier and more flexible to apply than these known classical rules.     

How Subchronic and Chronic Health Effects can be Neglected for GMOs, Pesticides or Chemicals

Chronic health effects are increasing in the world such as cancers, hormonal, reproductive, nervous, or immune diseases, even in young people. During regulatory toxicological subchronic tests to prevent these on mammalian health, prior commercialization of chemicals, including pesticides and drugs, or GMOs, some statistically significant findings may be revealed. This discussion is about the need to investigate the relevant criteria to consider those as biologically significant. The sex differences and the non linear dose or time related effects should be considered in contrast to the claims of a Monsanto-supported expert panel about a GMO, the MON 863 Bt maize, but also for pesticides or drugs, in particular to reveal hormone-dependent diseases and first signs of toxicities.     

Difference of two dependent sensitivities and specificities: Comparison of various approaches

In diagnostic studies, a new diagnostic test is often compared with a standard test and both tests are applied on the same patients, called paired design. The true disease state is in general given by the so‐called gold standard (most reliable method for classification), which has to be known for all patients. The benefit of the new diagnostic test can be evaluated by sensitivity and specificity, which are in fact proportions. This means, for the comparison of two diagnostic tests, confidence intervals for the difference of the dependent estimated sensitivities and specificities are calculated. In the literature, many comparisons of different approaches can be found, but none explicitly for diagnostic studies. For this reason we compare 13 approaches for a set of scenarios that represent data of diagnostic studies (e.g., with sensitivity and specificity ?0.8). With simulation studies, we show that the nonparametric interval with normal approximation can be recommended for the difference of two dependent sensitivities or specificities without restriction, the Wald interval with the limitation of slightly anti‐conservative results for small sample sizes, and the nonparametric intervals with t‐approximation, and the Tango interval with the limitation of conservative results for high correlations.     

Testing against Ordered Alternatives in One-way Layout

In this paper we investigate a simple method of modifying well known nonparametric tests for the several samples location problem to yield a class of test statistics suitable for ordered alternatives. Optimum member of the class is identified in each case and its efficacy obtained. The method is applied to five statistics.     

Deep mutational scanning identifies SARS-CoV-2 Nucleocapsid escape mutations of currently available rapid antigen tests

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Estimates of a Treatment Effect Based on Censored Data Rank Tests

Linear rank test statistics are applied to the problem of estimating a treatment effect if two sets of censored failure time data are compared and the distributions of the log-failure times of the two samples are assumed to differ only in location. Rank tests for this accelerated failure time model are reviewed and Hodges-Lehmann type estimates for the shift parameter are proposed. Properties of these estimates are investigated, computational aspects are discussed and an example is presented.     

Generalized Rank Transformations for Tests of Survival

The asymptotic equivalence of nonparametric tests and parametric tests based on rank-transformed data (CONOVER and IMAN , 1981) can be extended to the case of censoring. This paper presents generalized rank transformations for analyses of censored data, of interval-censored data and of survival data with uncertain causes of death. A Monte Carlo study and an analysis of leukemia remission times demonstrate excellent agreement of suggested procedures with GEHAN 'S (1965) and PRENTICE 'S (1978) tests.     

Exact Calculation of Permutational Distributions for Two Dependent Samples I

A simple Fortran subroutine is given for the calculation of permutational distributions. Important special cases are Fisher's randomization test, the Wilcoxon signed ranks test and the sign test. The algorithm works in polynomial time. Thus it can be used even for micro-computers within justifiable time limits.     

Effect of 16 weeks diving practice at two different times of day on the pulmonary function,spirometry measurements and 6-minute walk test data of healthy professional Tunisian scuba divers

The aim of this study was to investigate the effect of time of the day (TOD) and 16 weeks diving practice (16WDP) on the spirometric parameters and 6-min walk test data (6MWT) on professional Tunisian scuba divers. In randomized order, 36 health males divided into 3 groups [morning practice group) (MPG): n = 12; evening practice group (EPG): n = 12; control group (CG) n = 12] participated voluntary in this study. They performed spirometry measurements and 6MWT during two periods: [before-season (June 05–10), and after-season (October 05–10)]. Our results revealed that assessment sessions comprised the following: FVC, FEV1, FEV1/FVC and PEF. Results were analyzed by applying repeated measures analysis of variance ANOVA. The spirometric parameters were similar upon two times of day on both EPG and MPG before the season (i.e. FEV1, FVC). Likewise, our finding revealed a significant decrease in lung functions following the 16 weeks practice of scuba diving upon two times of day. Thus, this period of hyperbaric scuba diving practice lead a significant alteration of lung function parameters with decrease of percent of variation in EPG vs. CEG compared to MPG vs. CMG: (i.e. FEV1, FVC, and PEF). In conclusion, 16 weeks of hyperbaric scuba diving lead a significant change in the spirometric and 6MWT values and respiratory problem with damage on lung function in healthy adult divers older than 40 years. Professional divers are recommended to have practice diving in the morning.