A statistical analysis of multiple-choice answers is performed to identify anomalies that can be used as evidence of student cheating. The ratio of exact errors in common (EEIC: two students put the same wrong answer for a question) to differences (D: two students get different answers) was found to be a good indicator of cheating under a wide range of circumstances. The longest continuous streak of identical answers was also a good indicator of cheating, especially for short tests with a low class average. This article also discusses how to interpret the data for use in practical circumstances and discusses ways to prevent cheating. (Contains 8 tables.)