1: Estimation of residuals assumes an accurate model, and we cannot make that assumption in EFA. [return]

2: In this context, we will use the term “outlier” to loosely describe a thing that does not belong. There are more technical definitions for different contexts, but you will have to indulge us here. There are also some in the scholarly community who insist that removing outliers (and indeed, data cleaning in general) is detrimental to the scientific process. The first author has published many articles, given numerous talks and, ultimately, wrote an entire book to empirically demonstrate why this position is wrong-headed. [return]

3: Please note, parts of this section are adapted from Osborne, J.W., & Blanchard, M. R. (2011). [return]

4: One option, used in this particular data set included having 20 questions with four choices: A-D, with other questions scattered throughout the test, and particularly near the end, with items that contain only three (A-C) or two (A-B) legitimate answers. Students or respondents choosing illegitimate answers one or more times can be assumed to be randomly responding, as our results show. [return]