University of Sheffield: Lab Report for PAN at CLEF 2010

This paper describes the University of Sheffield entry for the 2nd international plagiarism detection competition (PAN 2010). Our system attempts to identify extrinsic plagiarism. A three-stage approach is used: pre-processing, candidate document selection (using word n-grams) and detailed analysis (using the Running Karp-Rabin Greedy String Tiling string matching algorithm). This approach achieved an overall performance of 0.20 in the official evaluation with a precision of 0.40, recall of 0.16 and granularity of 1.21.