ABSTRACT
ANALYSIS OF DIFFERENCES BETWEEN TWO LEVELS OF AN INDEPENDENT VARIABLE Introduction The present chapter deals with designs that involve one independent variable with only two levels. Parametric and non-parametric tests are introduced that analyse between-and within-subjects designs. The use of z-tests to evaluate larger samples in non-parametric tests is explained. The power and effect size of the two-sample t-test and its non-parametric equivalents are discussed. An additional measure of effect size for certain designs with nominal data-the odds ratio-is presented.
