Detecting Student Code Plagiarism with MOSS

Detecting Student Code Plagiarism with MOSS

Table of Contents

1. Introduction
2. What is Moss?
3. How Does Moss Work?
4. Step 1: Downloading the Moss Script
5. Step 2: Organizing Your Files
6. Step 3: Using Moss Script Options
7. Step 4: Testing Moss in Practice
8. Understanding Moss Results
9. Advantages of Using Moss
10. Limitations of Moss
11. Conclusion

Introduction Welcome to the first video of Programming Workbook. In this video, we will be discussing a tool called Moss that helps detect code plagiarism among students. Moss is a free tool that can check for similarities in code by comparing lines. This article will guide you through the process of using Moss for code plagiarism detection.

What is Moss? Moss is a tool designed to detect if two students have similar code by comparing lines. It is commonly used for programming assignments and projects to identify potential cases of plagiarism. Moss is a free tool for non-commercial use and offers a simple yet effective way to analyze code similarities.

How Does Moss Work? Before we dive into using Moss, it is important to understand how the tool operates. Moss works by submitting files or directories containing the students' code to a remote server. The server processes the files and generates a URL with the file comparison results. It is crucial to note that Moss does not provide the actual files; instead, it gives you a URL where you can view the comparison report.

Step 1: Downloading the Moss Script To begin using Moss, you need to download the Moss script onto your machine. To do this, visit the Moss homepage or simply search for "Moss" on your favorite search engine. Once on the Moss website, you will need to provide your email address to receive the script. The email content should be as follows: "register user me" followed by your email address. Upon sending the email, you will receive a user ID, which is essential for further steps.

Step 2: Organizing Your Files While not mandatory, organizing your files is highly recommended to avoid a cluttered file system. Create a directory structure where you store the downloaded Moss script and the students' project files. By keeping the files neatly organized, you can easily access and submit them for plagiarism detection.

Step 3: Using Moss Script Options The Moss script provides several options that customize the plagiarism detection process. For instance, you can specify the programming language by using the "-l" flag followed by the language name (e.g., Java). Additionally, you can use the "-d" flag if each student's project is in a different directory. To set a base file template, use the "-b" flag followed by the path to the base file. Another useful option is the "-m" flag, which sets the maximum number of occurrences a given code can have before being ignored. Lastly, you can include a comment in the report using the "-c" flag followed by a string comment.

Step 4: Testing Moss in Practice Now that you have organized your files and configured the Moss script options, it's time to test the tool. Open the terminal and navigate to the directory where you saved the Moss script and the student project files. In the terminal, enter the command "perl mossnet.pl" (or the filename you used for the script). Specify the language with the "-l" flag, and if necessary, provide additional flags such as "-d" or "-b" to set the project directories and base file. Finally, submit the files by listing their directories or filenames. Moss will process the files remotely, and you will receive a URL with the comparison report.

Understanding Moss Results When you access the URL provided by Moss, you will find a comparison report of the submitted files. The report will display the similarities between the code files, highlighting similar lines in different colors. Variables or functions that have been renamed will be recognized as the same entity. For a comprehensive understanding of the results, it is essential to thoroughly analyze the report.

Advantages of Using Moss

• Moss is a free tool for non-commercial use.
• It effectively detects similarities between code files, aiding in identifying potential cases of plagiarism.
• Moss can identify code similarities even if variables or functions have been renamed or if minor changes have been made.

Limitations of Moss

• Moss operates remotely, which means You do not receive the actual files but rather a URL with the comparison report.
• While Moss is effective in detecting code similarities, it might not accurately identify all instances of plagiarism, especially if significant modifications have been made.
• Moss primarily focuses on detecting similarities in code and does not consider the overall structure or logic of the program.

Conclusion Using Moss for code plagiarism detection can greatly assist in maintaining academic integrity and fairness. By following the steps outlined in this article and understanding the advantages and limitations of Moss, you can effectively leverage this tool to identify and address potential cases of plagiarized code among students.