Visualizing and predicting the path to an undergraduate physics degree at two different institutions

This study examined physics major retention to degree at two institutions with substantially different admissions selectivity. Two modes of leaving the physics major were examined: leaving college and changing to another major while staying in college. The risk of leaving college while still enrolled as a physics major was highest in the spring freshman semester. The changing major risk was substantially different between the two institutions. For the less selective institution, the students changed major at the highest rate in the fall sophomore semester. For the more selective institution, the risk of changing major was high through the first two years of college with highest risk in the fall freshman semester and the fall junior semester. Different features were important in predicting the two modes of leaving; these also differed between institutions. For the less selective institution, math readiness (being academically prepared to enroll in Calculus 1 in the fall freshman semester) was the most predictive feature for leaving the physics major while staying in college; high school GPA was the most important feature for predicting both leaving college and graduating with a physics degree. For the more selective institution, ACT composite scores were the only significant predictor of retention. The role of math readiness was dramatic at the less selective institution with 41% of students not math ready upon enrolling in college as physics majors; 59% of these students failed to enroll in the first required physics class.

Figure 1

Sankey plot showing major changing and graduation patterns for students who elect a physics major at any point in their undergraduate career. Each group of two bars represents an academic year; fall semesters are odd numbers, spring semesters even.

Figure 2

Fraction departed or graduated for students entering the university declared as physics majors.

Figure 3

Hazard functions. The graduation hazard is plotted on a different scale shown by the right vertical axis. For Institution 1, each semester plotted has at least 50 students enrolled as physics majors. Only 5 semesters could be plotted for the smaller Institution 2; these semesters enroll 54, 40, 29, 24, and 19 students, respectively.

Figure 4

Traversing the major from entry to Modern Physics for students at Institution 1 who elect a physics major in their first semester. The figure uses the abbreviations $<\mathrm{Calc}$ for students whose first mathematics class is less advanced than Calculus 1, Calc for students whose first mathematics class is is Calculus 1, and $>\mathrm{Calc}$ for students whose first mathematics class is more advanced than Calculus 1.