Software metrics and plagiarism detection

The reliability of plagiarism detection systems, which try to identify similar programs in large populations, is critically dependent on the choice of program representation. Soft-ware metrics conventionally used as representations are described, and the limitations of metrics adapted from software complexity measures are outlined. An application-specific metric is proposed, one that represents the struc-ture of a program as a variable-length profile. Its constituent terms, each recording the control structures in a program fragment, are ordered for efficient comparision. The supe-rior performance of the plagiarism detection system based on this profile is reported, and deriving complexity measures from the profile is discussed. 1