Measuring Whitespace Pattern Sequences as an Indication of Plagiarism

Nikolaus Baer, Robert Zeidman

Zeidman Consulting, Cupertino, USA.
Zeidman Consulting, Cupertino, USA..

DOI: 10.4236/jsea.2012.54029                

Abstract

There are several methods and technologies for comparing the statements, comments, strings, identifiers, and other visible elements of source code in order to efficiently identify similarity. In a prior paper we found that comparing the whitespace patterns was not precise enough to identify copying by itself. However, several possible methods for improving the precision of a whitespace pattern comparison were presented, the most promising of which was an examination of the sequences of lines with matching whitespace patterns. This paper demonstrates a method of evaluating the sequences of matching whitespace patterns and a detailed study of the method’s reliability.

Keywords

Plagiarism; Source Code; Source Code Similarity; Whitespace; Obfuscation; Indentation; Maintainability; Copyright Infringement; Intellectual Property; Litigation; Open Source

Conflicts of Interest

The authors declare no conflicts of interest.

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