Plago: A system for plagiarism detection and intervention in massive courses

Abstract

Plago is as a tool for Instructors and TAs, especially in massive (200+ students) courses. Plago imports students’ essay style PDF assignment submissions directly from Canvas LMS and prepares them for scanning for plagiarism. Comparisons against a corpus of tens of thousands of existing papers takes a few minutes and flags potential plagiarism based on match percentages. Additionally, Plago provides evidence of plagiarism in way of a side by side comparison of papers with highlighting on matching text between the two papers. Plago uses an extrinsic method of plagiarism detection based on n-gram comparisons for content and structural similarities. The paper also provides research and discussion on intrinsic methods.