5. This exercise is designed to show differences in findings depending on whether you use simultaneous or sequential regression, and depending on the order of entry in sequential regression. Angela Duckworth and Martin Seligman (2005) were interested in the effects of self-discipline on students’ academic performance. They measured the self-discipline

(degree of self-regulation and lack of impulsiveness across multiple domains) of 154 eighth-graders in the Fall, and used that to predict (or was it explain?) final GPA in the Spring. Also controlled were students’ IQs and their previous GPA, also measured in the Fall. The data are in the file “Duckworth Seligman sim data.sav”; the data are simulated but are designed to produce results consistent with the findings of the original study.