Alternatives to the Grade Point Average as a Measure of Academic Achievement in College

. e s e a r c12 Report'ernes001-4Alternatives to the Grade Point Average as a Measure of Academic Achievement in CollegePui-Wa Lei Dina Bassiri E. Matthew SchultzACTDe c e m o e Fter 2 0 0 1 For additional copies write: ACT Research Report Series P.O. Box 168Iowa City, Iowa 52243-0168©2001 by ACT, Inc. All rights reserved. Alternatives to the Grade Point Average as a Measure of Academic Achievement in CollegePui-Wa Lei Dina Bassiri E. Matthew Schulz AbstractCollege GPA, a linear combination of assigned grades from different courses, is widely known to be an imperfect measure of student achievement. This unreliable measure decreases the predictive validity of college admission tests. Research has shown that adjusting course grades for differential grading practices improves predictive validity. Relative rankings of students on adjusted college GPAs are also more consistent with their course grade standings. These findings were replicated with course grade data from consecutive cohorts of two universities using 4 polytomous IRT and 3 linear models. Unlike previous studies, course parameter estimates and regression weights were cross-validated. Both same-sample and cross-validated alternative measures showed improvement over simple GPA. The rating scale and partial credit IRT models excelled on multiple correlations with admission test scores. The graded response IRT model was the most unstable across cohorts. Implications of these findings and limitations of the studies are discussed. Alternatives to the Grade Point Average as a Measure of Academic Achievement in CollegeGPA, a linear combination of grades assigned in different courses, is not an ideal measure of student achievement because it reflects not only academic achievement, but also course taking strategies and instructor grading practices. Unless course selection is not allowed and all instructors are willing to adhere to a universal grading standard, GPAs for different students do not necessarily have the same meaning.Several problems are associated with the use of GPA as a measure of academic achievement in college. One is that it is difficult to select candidates from different departments or different institutions for scholarship or employment purposes (e.g., Caulkins, et al., 1996). Different teachers/professors have different grading criteria according to their own perception of student achievement (Hoover, Roller, Liddell, Moore, McCarthy, and Hlebowitsh, 1999). Perhaps due to the composition of “like-minded” individuals, departments vary in their grading tendencies (Hoover, et al., 1999; Johnson, 1997). Grade point averages are, therefore, not strictly comparable among students, particularly across departments or majors.The use of GPA as a measure of academic achievement also drives grade inflation. It has been suggested that instructors lower their standards in order to improve their course ratings by students. Students may shop for courses taught by leniently grading instructors (e.g., Johnson, 1997) or switch to departments that tend to give high grades (e.g., Young, 1993). As a result, grades may be raised without reflecting increased students’ abilities, a phenomenon known as grade inflation (Bejar & Blew, 1981). Note that grade inflation is not necessary specific to the college level. Ziomek and Svec (1995) documented a similar phenomenon at the high school level. Relying on GPA as a measure of academic achievement also makes it more difficult to evaluate college admissions tests (e.g., Young, 1993; Strieker, Rock, Burton, Muraki, & Jirele, 1994). Admissions tests are rightly expected to predict grades but should not be expected to predict whether a student will choose an easier curriculum.To make course grades more comparable, a viable alternative to imposing a common grading standard on all instructors (or to denying course selection by students) is to adjust GPA for differential course difficulty (Caulkins, Larkey, and Wei, 1996). Adjusted-GPA, like GPA, represents student achievement on a single (unidimensional) scale and is constructed entirely from course grade data. An adjusted-GPA does not resolve the underlying problem of representing an inherent multidimensional domain with respect to the specific subject areas with a simple unidimensional measure. Other dimensions may also include non-cognitive characteristics such as attending class and turning in homework. However, it is better than GPA because it reduces the error arising from differential course-taking patterns and variation in course difficulty. It is hoped that by leveling course difficulty, incentives other than learning the course content will be discouraged in the long run. Immediate effects of adjusting GPA include improved predictive validity of college