The Conceptual Survey of Electricity and Magnetism (CSEM) has been utilized to measure learning gains in electricity and magnetism (E&M) physics courses, where "correct" vs "incorrect" responses are typically used for analysis. However, such comparisons do not necessarily identify specific changes in student reasoning from pre- to post-instruction. To address this issue, we have generated network-like graphs for each question: Responses at pre- and post-test are represented by nodes connected by edges representing the change in student response choice. We demonstrate the visualizations using data from CSEM responses from over 2500 students at Cornell University across 12 semesters of an introductory E&M course. We demonstrate a vector analysis method that can categorize response patterns and quantify the way students change their responses. We show the potential use of these methods for both instructors as well as for answering deeper research questions.