The purpose of this study was to examine the Practice Difficulty on exam performance for each of the four exam given during the semester. Practice Difficulty was a 3-condition variable practice problems were either about the same difficulty as the exam problems (=1), they were easier than the exam problems (=2), or they were more difficult than the exam problems (=3). Different sections of the ...

Based on notes by Elizabeth Ellinger, Spring 2004, as expanded and modified by Bruce E. Trumbo, 2005-08. Copyright © 2005, 2008 by Bruce E. Trumbo. All rights reserved. 8.1.1. For your convenience the breaking strength measurements in the table above have been repeated below, reading across each row of the table. Put them into c1 of a Minitab worksheet; label it PSI. Then use the patterned data...

A grouping or blocking of observations can be achieved by using categorical or dummy variables. Examples of categorical variables include gender, country of origin, job title and experimental treatment. This should be contrasted with ordinal variables, such as age class, highest degree attained or a score on a 5-point scale with values comprised between strongly agree and strongly disagree. The...

This Handout illustrates traditional mixed-model ANOVA analyses of the data from my study of host effects on parasitoid larvae (Data Set 6) when the host species is treated as a random factor. Note: Treating species as random would not be reasonable in reality, given that these two moth species are the only common hosts for this parasitoid in North Carolina, where I conducted this study. It als...

We consider a possible scenario of experimental analysis on heuristics for optimization: identifying the contribution of local search components when algorithms are evaluated on the basis of solution quality attained. We discuss the experimental designs with special focus on the role of the test instances in the statistical analysis. Contrary to previous practice of modeling instances as a bloc...

This appendix contains the results obtained from the analysis of variance described in chapter three using " set " as the second factor.