Educational integrity in the age of generative AI: an interpretable random forest-based detection framework
摘要
As generative AI tools become ubiquitous in education, the need for reliable, transparent, and efficient methods to ensure academic integrity is paramount. While deep learning models offer high accuracy, their computational cost and lack of interpretability often hinder practical deployment. To address this gap, this study evaluates the practical viability of classical machine learning frameworks for detecting AI-generated text. The framework utilizes TF-IDF features and evaluates six classifiers through a rigorous 10-fold stratified cross-validation. Our results demonstrate that multiple classical models, including Support Vector Machines (SVM) and Naive Bayes, achieve stable and near-perfect mean F1-scores (0.9986 and 0.9984, respectively). Crucially, our analysis of the performance-efficiency trade-off highlights that Naive Bayes and Logistic Regression provide this top-tier accuracy with significantly lower computational cost, making them highly practical solutions for real-world deployment. Explainability was enhanced using SHAP and LIME to ensure transparency. This study contributes a robustly evaluated, lightweight, and interpretable framework for AI text detection suitable for educational applications, emphasizing that efficiency is as critical as accuracy for widespread adoption.