Plagiarism Detection

Currently the most widely used code plagiarism detection software is serviced by Moss

• ~give/stable/bin/ contains scripts to make the process easier:

• moss - sends submissions to moss for processing.

• example:

• % moss -l python -m 4 -b template.py -d "*/*.py"

• moss_setup - retrieve submissions and put them into directories suitable for moss-ing.

• example:

• % ~give/stable/bin/moss_setup  21T2  ass1

  • a plague directory will be created under ~/21T2.work/ass1
  • remove any files not to be included in moss plagiarism detection
  • copy template files to plague/Samples to ignore similarity from these files

• moss_run - wrapper script for moss script.

• example:

• % ~give/stable/bin/moss_run  en1811  21T2  ass1  python  "*/*.py"

• % ~give/stable/bin/moss_run  -d /home/en1811/21T2.work/ass1/plague  python  "*/*.py"

  • last two arguments specify the programming language (python) and which files to process (all .py files for each student).

• plague.pl

  • Paste everything on moss summary page into moss_report_file 

  • Look at similarities in code on moss pages and select plagiarised pairs:

  • % plague.pl -s  assignment  moss_report_file  selected_plague_file

  • Report assignment mark, submission history

  • % plague.pl -s  assignment  selected_plague_file

Plagiarism Procedures