Assessing Students' Understanding of Uncertainty in Undergraduate Physics Laboratory Courses at a Major Canadian University

TL;DR

This study assesses undergraduate physics students' understanding of uncertainty at McGill University, revealing progress over courses but persistent misconceptions, using the CDPA test across multiple years and course levels.

Contribution

It introduces the use of the CDPA assessment to track conceptual understanding of uncertainty and identifies specific gaps in student knowledge in undergraduate physics labs.

Findings

Student understanding of uncertainty improves over consecutive courses.

No significant difference in scores before and after the pandemic.

Many students still struggle with basic data analysis and curve fitting.

Abstract

Over the last five years, the McGill University Office of Science Education (OSE) has partnered with faculty members from the Department of Physics to form an education research group with the aim of charting the progression of student conceptual understanding of uncertainties across their undergraduate degree. The research conducted by this group seeks to provide further insight into the experimental skillset that students gain through undergraduate laboratory courses and noticeable gaps in student understanding that the department could address. In this paper, we evaluate the conceptual understanding of uncertainty using the Concise Data Processing Assessment (CDPA) test. First, we characterize the physics laboratory curriculum at McGill University by evaluating the evolution of CDPA scores across consecutive laboratory courses, and further propose the utilization of this tool for identifying gaps in student understanding. Following the analysis of student responses (N = 2023), we specifically investigate data collected in second-year courses to better understand what student errors reveal about common misconceptions in experimental physics. This more in-depth analysis focuses on data collected from students at the beginning and end of two consecutive experimental laboratory courses that build on each other. By the end of the second course, students have engaged with all the material covered in the CDPA test. Overall results show an upward shift in student understanding of uncertainties over time. Interestingly, we did not observe any change in CDPA scores comparing throughout and post-pandemic scores. Despite the upward shift, many students continue to struggle with uncertainties, basic data analysis, and curve fitting.