facorread/fpdt

Fabio's plagiarism detection tool

fpdt: Fabio's plagiarism detection tool

Copyright and license

Copyright (C) 2016 - 2017 Fabio Correa [email protected]

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/.

Description

This is a small C++ program designed to detect intra-corpal plagiarism; this is, students copying texts among themselves.

This program is not designed for general use. You are welcome to use it to develop your own derivative program for your own purposes. In my case, this program is designed to work with student assignment submissions downloaded from the University of Maryland's ELMS learning management system.

In my class webpage the students download the assignment questions in the form of docx and xlsx documents; they answer the questions directly there, and submit the completed documents via ELMS.

This program takes as input the file submissions.zip downloaded from the ELMS assignment page. It will use the unzip program to extract the submissions into a fpdt folder, then it will extract the text from all submissions into memory.

This program optionally takes as input the original questions documents, which is highly recommended; otherwise the program will interpret the questions and guides as plagiarism as they will appear in every submission.

Workflow

Please read carefully and understand all instructions in this section, as they will result in file deletion.

The workflow of plagiarism detection starts with a text terminal located at the folder to which web downloads are saved (usually ~/Desktop or ~/Downloads).

rm -rv submissions*.zip *.docx *.xlsx fpdtSubmissions fpdt.txt

The ELMS assignment webpage is opened, the questions are downloaded, and then the Download Submissions link is clicked. Once the files are downloaded, the program is invoked at the terminal without changing the working directory. Every docx and xlsx file currently at the download directory (not subdirectories or zipfiles) is taken as questions input.

Output

This program produces a file fpdt.txt containing a list in which each entry consists of the names of the students and the phrases that match between them, in decreasing length order. Each item serves as a red flag for your own inspection of their assignments.

Known issues

This program will certainly output some questions as false positives. This is because hashes are calculated per sentence, but sentences are identified by the program using a primitive algorithm. This is why your own inspection of the assignments is required after looking at the output. There are no plans to address this issue.

System requirements

This program requires cmake, a recent C++14 compiler, and the unzip utility.

Source code

The source code for this program is hosted at https://gitlab.com/facorread/fpdt