Two tests of heterozygosity for phenylketonuria, the phenylalanine/tyrosine ratio in the plasma after a fast and the response to an oral load of phenylalanine, have been compared in obligate heterozygotes for phenylketonuria and apparent normal homozygotes. The discriminatory ability of the tests is measured using both parametric and non-parametric methods, the correlation between them is deter...

Non-parametric paired analyses are approached through the same logic as the parametric paired t-tests: a 2 sample paired analysis can be reduced to a 1 sample test by creating a single distribution of the differences between each pair. If the distribution of the differences are nonnormal, and cannot be normalized by transforming the data to some other ratio scale, a 1 sample non-parametric test...

We present a novel characterization of the generalized family wise error rate: kFWER. The interpretation allows researchers to view kFWER as a function of the test statistics rather than current methods based on p-values. Using this interpretation we present several theorems and methods (parametric and non-parametric) for estimating kFWER in various data settings. With this version of kFWER, re...

Several tests for a zero random effect variance in linear mixed models are compared. This testing problem is non-regular because the tested parameter is on the boundary of the parameter space. Size and power of the different tests are investigated in an extensive simulation study that covers a variety of important settings. These include testing for polynomial regression versus a general smooth...

In adaptive randomized experiments, researchers verify that random allocation yielded equivalent experimental groups before proceeding with data analysis. Given a precise definition of balanced groups (e.g., Cohen’s d < 0.5 for a continuous covariate), researchers may plan to keep reshuffling participants until balance is achieved. However, reshuffling can invalidate standard parametric tests, ...

Two frequently used parametric statistics of person-fit with the dichotomous Rasch model (RM) are adjusted and compared to each other and to their original counterparts in terms of power to detect aberrant response patterns in short tests (10, 20, and 30 items). Specifically, the cube root transformation of the mean square for the unweighted person-fit statistic, t, and the standardized likelih...