🤖 AI Summary
To address the premature convergence and slow convergence issues of the Whale Optimization Algorithm (WOA) in XGBoost hyperparameter optimization, this paper proposes a Nonlinear Adaptive Whale Optimization Algorithm (NAWOA). NAWOA integrates five key enhancements: Good Nodes Set-based initialization, a Leader-Followers Foraging mechanism, a dynamic prey-encircling strategy, a triangular cooperative hunting structure, and a nonlinear convergence factor—collectively strengthening global exploration and convergence stability. We embed NAWOA into XGBoost hyperparameter tuning to construct the NAWOA-XGBoost model, applied to early academic potential prediction for students—a multiclass, class-imbalanced educational task. Evaluated on a real-world dataset of 495 students, the model achieves accuracy = 0.8148, macro-F1 = 0.8101, AUC = 0.8932, and G-mean = 0.8172, consistently outperforming standard XGBoost and WOA-XGBoost. Results validate both the effectiveness and practical applicability of the proposed algorithmic improvements.
📝 Abstract
Whale Optimization Algorithm (WOA) suffers from limited global search ability, slow convergence, and tendency to fall into local optima, restricting its effectiveness in hyperparameter optimization for machine learning models. To address these issues, this study proposes a Nonlinear Adaptive Whale Optimization Algorithm (NAWOA), which integrates strategies such as Good Nodes Set initialization, Leader-Followers Foraging, Dynamic Encircling Prey, Triangular Hunting, and a nonlinear convergence factor to enhance exploration, exploitation, and convergence stability. Experiments on 23 benchmark functions demonstrate NAWOA's superior optimization capability and robustness. Based on this optimizer, an NAWOA-XGBoost model was developed to predict academic potential using data from 495 Computer Science undergraduates at Macao Polytechnic University (2009-2019). Results show that NAWOA-XGBoost outperforms traditional XGBoost and WOA-XGBoost across key metrics, including Accuracy (0.8148), Macro F1 (0.8101), AUC (0.8932), and G-Mean (0.8172), demonstrating strong adaptability on multi-class imbalanced datasets.