The Effects of Alternative Interpretations of Incomplete and Withdrawal Grades on Course Placement Validity Indices

ACT Research Report Series93-3The Effects of Alternative Interpretations of Incomplete and Withdrawal Grades on Course Placement Validity IndicesCheng H. Ang Julie P. IMobleAugust 1993 For additional copies write: ACT Research Report Series P.O. Box 168 Iowa City, Iowa 52243©1993 by The American College Testing Program. All rights reserved. THE EFFECTS OF ALTERNATIVE INTERPRETATIONS OF INCOMPLETE AND WITHDRAWALGRADES ON COURSE PLACEMENT VALIDITY INDICESCheng H. Ang and Julie Noble A B S T R A C TIn validating tests for course placement in college, the criterion variable is usually defined in terms of the grade earned in a particular standard course. For example, success m ay be defined as com pleting the standard course with a grade of C or higher. This study considered the issue of interpreting incomplete (1) and withdrawal (W) grades either as unsuccessful outcomes or as m issing data. The effects of either type of interpretation on placement indices and optimum cutoff scores were studied. The data for the study were obtained from four two-year colleges through their participation in a pilot study of the ACT Course Placem ent Service. Courses included were m athematics and E nglish/read ing courses. ASSET test scores were used as predictor variables.The results of this study showed that interpreting I and W grades as unsuccessful outcom es, rather than as missing data, generally resulted in low er conditional probabilities of success, higher optimal cutoff scores, and higher estimated delta accuracy rates.The manner in which I and W grades are interpreted should depend on an institution's policy or philosophy on those grades. Ideally, grades of I should be changed to grades of A through F or S / U before being included in the analyses of course placem ent criteria, and only students who received grades of W because of academic reasons should be classified as unsuccessful. If course placement accuracy indices were determined using these criteria, then the resulting optimum cutoff scores would be more accurate and appropriate. THE EFFECTS OF ALTERNATIVE INTERPRETATIONS OF INCOMPLETE AND WITHDRAWALGRADES ON COURSE PLACEMENT VALIDITY INDICESAlthough grading policies may differ from one institution to another, most postsecondary institutions use a grading scale of A to F to denote excellent to failing performance in a course, and grades of I and W to denote incomplete work and withdrawal from a course. Some institutions may also use combinations of grades, such as withdrawal pass (W?) or withdrawal fail (WF). Students may receive grades of I or W for academic problems, such as the inability to cope with the demands of a course; or for nonacademic problems, such as illness, emotional distress, or financial difficulty. Institutions may also differ in how grades of I are maintained. Grades of I may be permanently kept on transcripts, or the grades may be changed to failure (F) if supplementary assignments (or course requirements) are not completed by a prespecified deadline.Many colleges, particularly two-year community colleges, have an open admission policy for all high school graduates. The implementation of this policy, and attempts by colleges to provide opportunities for students to succeed, has resulted in course placement policies and developmental/remedial instruction. Because course placement cutoff scores are often developed from statistical analyses of placement test scores and course grades, the interpretation of I and W grades as either unsuccessful outcomes or missing data (deleted from the analysis) may affect the cutoff scores selected for course placement and the resulting course placement decisions made for future students.If course placement validity indices and optimum cutoff scores differ because of the way in which 1 and W grades are interpreted, then thoughtful consideration must be given to how these grades are interpreted when evaluating the accuracy of course placement cutoff scores. Correct course placement decisions promote student success and foster persistence among students. Incorrect course placement decisions, however, waste students' time in school and educational expenses, as well as institutions' personnel allocations and costs.The purpose of this paper was to compare optimal placement cutoff scores and placement validity indices resulting from two interpretations of 1 and W grades, where I and W grades were interpreted as unsuccessful outcomes or as missing data. The placement validity indices and cutoff scores were deve