A practical approach to overcoming biases in comparing student performance in higher education

Abstract In times of rankings and performance benchmarks, data on average marks of higher education students are very common internationally and are often used as quality indicators in practice. We discuss the principles behind the distribution of average marks of students. These principles need to be taken into account when calculating the percentile of (the average mark of) a student. An informative percentile is obtained only if the average mark is compared to a distribution of averages that have been calculated based on the same number of credit points obtained by the student. We provide an empirical example from a university in Germany, which shows that percentile information can differ considerably when based upon different samples. Our findings indicate that the approach proposed in this study may not only be the most efficient approach for ranking students to be implemented into university practice, but may also contribute to a much more objective and credible grade reporting system for student performance.