Answer Watermarking: Using Answer Generation Assistance Tools to Find Evidence of Cheating

Christopher Cui, Jui-Tse Hung, Pranav Sharma, Saurabh Chatterjee, Thad Starner

Abstract: Cheating detection in large classes with online, take-home exams is an extremely difficult problem. While some cheating can be identified through statistical analysis of all student responses, this analysis can easily be fooled by "smart cheaters'' actively attempting to hide evidence of their unauthorized collaboration. We demonstrate the effectiveness of watermarks combined with creative question design to provide evidence of cheating. We provide results from an initial deployment of our answer watermarking method and do a case study into how "smart cheaters'' attempt to cover their tracks, demonstrating the need for more advanced methods of catching cheating in online, take-home exams.