Evidence that computer science grades are not bimodal

Abstract

Although it has never been rigorously demonstrated, there is a common belief that grades in computer science courses are bimodal. We statistically analyzed 778 distributions of final course grades from a large research university and found that only 5.8% of the distributions passed tests of multimodality. We then devised a psychology experiment to understand why CS educators believe their grades to be bimodal. We showed 53 CS professors a series of histograms displaying ambiguous distributions that we asked them to categorize. A random half of participants were primed to think about the fact that CS grades are commonly thought to be bimodal; these participants were more likely to label ambiguous distributions as "bimodal." Participants were also more likely to label distributions as bimodal if they believed that some students are innately predisposed to do better at CS. These results suggest that bimodal grades are instructional folklore in CS, caused by confirmation bias and instructor beliefs about their students.

Modularization for mastery learning in CS1: a 4-year action research study

“…Improving the academic results of CS1 courses can reduce student attrition, increase graduation rates, and increase the supply of qualified workers in scientific and technological fields to meet the growing demand. A wealth of research in computer science education has sought to explain why some students perform better than others in CS1 courses (Basnet et al, 2018;Guzdial, 2019;McCartney et al, 2017;Patitsas et al, 2019). One hypothesis for academic failure in CS1 courses relates to the cumulative nature of the materials and posits the existence of "stumbling points" in the learning path of programming: that is, there is a small number of identifiable skills and concepts that can have a major impact on a student's progress (Ahadi & Lister, 2013).…”

“…Thus, students who enroll in STEM curricula in higher education must typically learn computational thinking and programming at an accelerated pace in their first introductory course to the subject (Ahadi, et al, 2014). When this is done via traditional 'one size fits all' instructional approaches, students experiencing learning difficulties in introductory programming courses are rapidly overwhelmed by the pace of instruction, resulting in early attrition and high rates of course failure (Patitsas et al, 2019;Robins, 2010).…”

Sympathetic Activation in Deadlines of Deskbound Research - A Study in the Wild

“…Researchers know that the odds of having a paper or proposal accepted is low, and failure is the normal outcome [12,30]. This is not the case with most student exams, where the typical grade distribution is approximately Normal [31], and failure is the exception rather than the rule. In this context, our work is closer to deadline studies of funding solicitations.…”