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How Much Copied Stack Overflow Code Do Plagiarism Tools Actually Catch General 10 min
Alex Petrov Alex Petrov · 3 weeks ago

How Much Copied Stack Overflow Code Do Plagiarism Tools Actually Catch

Traditional similarity tools like MOSS and JPlag compare student submissions against each other but leave a massive blind spot: code copied directly from Stack Overflow, GitHub repositories, and online tutorials. This article examines how web source detection works, what it catches that peer comparison misses, and why both approaches together give you the real picture of code originality.

Teaching Code Attribution Before Students Write a Single Line Academic Integrity 11 min
Emily Watson Emily Watson · 4 weeks ago

Teaching Code Attribution Before Students Write a Single Line

Too many CS students treat code from Stack Overflow, GitHub, or AI tools as free for the taking. Teaching attribution as a core skill from the first assignment reduces plagiarism and builds professional habits. This article walks through concrete strategies, assignment patterns, and detection workflows that make attribution part of the learning process.

How Burstiness and Perplexity Catch AI-Generated Code AI Detection 9 min
Priya Sharma Priya Sharma · 4 weeks ago

How Burstiness and Perplexity Catch AI-Generated Code

Burstiness and perplexity aren't just linguistic curiosities—they're the primary statistical signals that distinguish human-written source code from LLM output. This article explains exactly how these measures work under the hood, with worked examples, real-world detection rates, and honest limitations.

One Community College's Web Code Plagiarism Strategy Case Studies 2 min
David Kim David Kim · 1 month ago

One Community College's Web Code Plagiarism Strategy

When intro programming students at a mid-sized community college were copying entire code snippets from Stack Overflow and GitHub, the department needed a scalable detection solution. By integrating Codequiry’s web-source matching into their grading pipeline, they reduced surface-level copy-paste incidents by 40% in a single semester while cutting manual review time by 60%.

What 1200 Python CS1 Submissions Reveal About AI-Written Code Signatures Case Studies 9 min
Emily Watson Emily Watson · 1 month ago

What 1200 Python CS1 Submissions Reveal About AI-Written Code Signatures

We analyzed 1200 introductory Python submissions from three semesters, applying perplexity, burstiness, and token-frequency analysis to separate human-written code from AI-generated samples. The results reveal a consistent set of statistical signatures that can catch GPT-generated and Copilot-assisted assignments—with measured false-positive rates at each threshold.

How Code Similarity Checks Catch Open Source License Violations General 9 min
Alex Petrov Alex Petrov · 1 month ago

How Code Similarity Checks Catch Open Source License Violations

Code similarity analysis isn't just for catching student plagiarism. Organizations use the same techniques to identify GPL and other open source license violations in their proprietary codebases. This article walks through the algorithms, real-world cases, and practical workflows for automated license compliance auditing.

Cross-Language Code Plagiarism Detection Methods Tested General 8 min
James Okafor James Okafor · 1 month ago

Cross-Language Code Plagiarism Detection Methods Tested

A rigorous head-to-head comparison of three cross-language code plagiarism detection approaches—tokenization, AST matching, and semantic fingerprinting—tested on 100 student-style assignments translated between Java, Python, and C++. We reveal which method catches translated loops, renamed variables, and switched control flow, and which one drowns in false positives.

Automating Code Plagiarism Detection in Your Grading Workflow Tutorials 8 min
Emily Watson Emily Watson · 1 month ago

Automating Code Plagiarism Detection in Your Grading Workflow

A practical walkthrough for CS instructors who want to wire code similarity checks directly into their grading workflow. Covers tooling choices, LMS integration, and how to layer in web-source and AI-generated code detection for a complete academic integrity pipeline.

K-gram Fingerprinting for Source Code Similarity Analysis General 9 min
Emily Watson Emily Watson · 1 month ago

K-gram Fingerprinting for Source Code Similarity Analysis

K-gram fingerprinting is the backbone of modern code plagiarism detection. This step-by-step guide walks through tokenization, k-gram generation, hashing, winnowing, and comparison — the exact pipeline used by MOSS and Codequiry. Includes Python code examples, algorithmic tradeoffs, and real-world scaling numbers.

Automated Code Similarity Checks in a CI Lab Pipeline Tutorials 7 min
Alex Petrov Alex Petrov · 1 month ago

Automated Code Similarity Checks in a CI Lab Pipeline

Setting up automated code plagiarism and similarity checks inside a CI pipeline cuts manual grading time and catches copying that individual reviewers miss. This practical guide walks through the architecture, tooling choices, and honest tradeoffs of running MOSS, JPlag, or Codequiry’s API on every lab push.

How Abstract Syntax Tree Comparison Detects Restructured Code General 1 min
Emily Watson Emily Watson · 1 month ago

How Abstract Syntax Tree Comparison Detects Restructured Code

Abstract syntax tree (AST) comparison is a powerful technique for detecting code plagiarism that has been restructured through variable renaming, method reordering, and whitespace changes. This article explains how AST comparison works, its strengths and limitations, and when to combine it with token-based methods for best results.

Why Some CS Departments Are Moving Beyond Moss for Plagiarism Detection General 8 min
Dr. Sarah Chen Dr. Sarah Chen · 1 month ago

Why Some CS Departments Are Moving Beyond Moss for Plagiarism Detection

Riverdale State University’s computer science department spent years relying on Moss to catch plagiarised assignments. But as student work grew more sophisticated — combining copied web code, heavy refactoring, and AI-generated fragments — the department realised token-based similarity alone was no longer sufficient. This case study covers how they transitioned to a multi-tool detection pipeline.