Why Grade Distribution Is Often Multi-Modal: an Uncertainty-Based Explanation

Authors

Olga Kosheleva, The University of Texas at El PasoFollow
Christian Servin, El Paso Community CollegeFollow
Vladik Kreinovich, The University of Texas at El PasoFollow

Publication Date

2-2019

Comments

Technical Report: UTEP-CS-19-10a

To appear in Proceedings of the World Congress of the International Fuzzy Systems Association and the Annual Conference of the North American Fuzzy Information Processing Society IFSA/NAFIPS'2019,, Lafayette, Louisiana, June 18-22, 2019.

Abstract

There are many different independent factors that affect student grades. There are many physical situations like this, in which many different independent factors affect a phenomenon, and in most such situations, we encounter normal distribution -- in full accordance with the Central Limit Theorem, which explains that in such situations, distribution should be close to normal. However, the grade distribution is definitely not normal -- it is multi-modal. In this paper, we explain this strange phenomenon, and, moreover, we explain several observed features of this multi-modal distribution.