Students’ stress prediction and explainable analysis based on improved decision trees

Introduction: Nowadays students are burdened with pressures from various aspects such as academics, social life, and career planning. It is of great significance to accurately predict their stress levels and analyze the key influencing factors. Methods: A stress prediction model for students was constructed based on an enhanced decision tree (DT) algorithm. First, nine machine learning algorithms, including logistic regression (LR) and DT, were compared to screen out the optimal base model. Then, the harris hawks optimization (HHO) algorithm was introduced to optimize the DT model and improve its prediction performance. Finally, the Shapley Additive Explanations (SHAP) model was applied to interpret the prediction results and analyze the contribution of various features to stress levels. Results: The DT algorithm showed outstanding performance among the nine compared models, achieving a prediction accuracy of 0.909. After optimization by the HHO algorithm, the HHO-DT model further improved the accuracy to 0.927 and had the fewest misclassified samples. SHAP analysis revealed that blood pressure, social support, and depression were the key features affecting students' stress level prediction. Discussion: The research results provide a scientific and effective basis for intervention measures taken by mental health educators, parents, and students themselves, which is helpful to relieve students' stress and promote their physical and mental health.