JPlag: finding plagiarisms among a set of programs

JPlag is a system that finds pairs of similar programs among a
given
set of programs. It has successfully been used in practice to
detect
plagiarisms among student Java exercise submissions.
Support for the languages C, C++ and Scheme is also available.
This report presents the design of JPlag, in particular the
comparison
algorithm, and carefully evaluates JPlag's performance on 12
rather
different sets of Java programs.
The results indicate that JPlag will find all plagiarisms with
only
very few exceptions. The execution time is less than one minute
for submissions of 100 programs of several hundred lines
each.