A simplified version of successive intervals scaling is described. Scale values for various datasets obtained with simplified successive intervals scaling are approximately linearly related to those obtained with traditional successive intervals scaling and the method of pair comparisons. The ease of use and some cautions in method use are…

Some of the methods originally used to find relationships between reliability and power associated with a single measurement are extended to difference scores. Results, based on explicit power calculations, show that augmenting the reliability of measurement by reducing error score variance can make significance tests of difference more powerful.…

Analysis of hypothetical data with dependent responses demonstrates how information loss caused by the overt response scale has an unknown influence on effect sizes in moderated regression analysis. The number of scale steps measuring the dependent variable results in a form of systematic error that alters interaction effect sizes. (SLD)

The importance of regression diagnostics in detecting influential data points is discussed, and five statistics are recommended for the applied researcher. The suggested diagnostics were used on a dataset of 24 subjects, and effects were analyzed. Colinearity-based diagnostics and diagnostics for a variety of procedures are discussed. (SLD)