This laboratory experiment was divided into four parts. In the first part, students evaluate previously published data and check their normality using histograms, Q-Q plots, the Shapiro-Wilk test, and boxplots. In the second part, two different groups were compared. First, data normality and homoskedasticity were checked by using the Shapiro-Wilk…

Problems associated with ranking a large number of objects are discussed. It is recommended that only a subset of the most preferred objects be ranked by each judge. A test statistic for testing the hypothesis of no difference in preference among the objects is developed for the recommended procedure. (Author/JKS)

The purpose of the current study was to investigate the relative performance of the parametric, rank, and normal scores procedures when the classical assumptions were met and under violations of these assumptions. This investigation included the normal scores as well as the rank test. (LMO)

When repeated measures are obtained on the same subjects, interobservation dependencies frequently are generated. The major ways in which these dependencies can arise are illustrated and it is shown how these dependencies may invalidate the use of analysis of variance (ANOVA) and its extension, trend analysis, as methods of evaluating the data of…