Assessing Student Ability to Interpret Regression Diagnostic Plots
Simple linear regression analysis is an important component of introductory statistics courses, and testing the validity of its assumptions is an important part of regression modeling and analysis. The traditional approach in introductory statistics courses is to use residual plots to assess possible departures from the key assumptions. Confirmatory statistics are typically not used. But do undergraduate students in these introductory courses have the ability to assess residual plots correctly? This paper presents the results of an Institutional Review Board (IRB) approved study to address this question. The results are interesting and have implications for the teaching of regression in introductory courses as well as for textbook authors who cater to these courses.