Optimized collusion prevention for online exams during social distancing

Online education surged during the COVID-19 pandemic, but home-based online exams increase opportunities for cheating, especially collusion. Rigorous online proctoring is costly, invasive to privacy, and may not prevent collusion. The authors develop an optimization-based anti-collusion approach for distanced online testing (DOT) that minimizes collusion gain by scheduling synchronized question sequences tailored to students, using prior knowledge of student competence. With this design, the collusion gain is reduced by 2–3 orders of magnitude relative to conventional exams where all students receive identical questions simultaneously. The theory provides control to reduce collusion gain to a very low level. A final exam conducted using the DOT format demonstrated success via statistical tests and a post-exam survey.

Mengzhou Li, Lei Luo, Sujoy Sikdar, Navid Ibtehaj Nizam, Shan Gao, Hongming Shan, Melanie Kruger, Uwe Kruger, Hisham Mohamed, Lirong Xia, Ge Wang