What impact does the use of mean versus median statistics have on student grading?

Abstract

The decision to calculate students' grades using a mean or a median statistic is an important consideration for educators. However, the choice of which statistic is used could have a significant impact on students' grades. Using real data from a preclinical course at a large pharmacy school in the United States, students' grades on five examinations were calculated using both mean and median statistics. With respect to grade performance, 84 (61.3%) students would have received a score increase if using the median statistic to calculate grades, whereas 53 (38.7%) students would have received a score decrease if using the median statistic. Letter grades for the course would also vary for some students depending on which statistic was used to calculate grades. The choice of using a mean or a median statistic can have a considerable effect on student grading. We encourage other educators to examine the influence of mean versus median statistics may have on grade calculations and select the statistic that will lead to the most valid indicator of student performance.