汾河流域灰绿空间对季节PM2.5 的非线性影响及阈值效应

邓椿, 聂桐, 张仲伍, 孙维峰

Seasonal variations and threshold effects of gray-green space on PM2.5 in the Fenhe River Basin

Chun Deng, Tong Nie, Zhongwu Zhang, Weifeng Sun

表2 7个机器学习模拟性能评估指标

Table 2 Evaluation metrics for seven machine-learning models’simulation performance

Model Train_R2 Train_RMSE Train_MAE Test_R2 Test_RMSE Test_MAE Elastic Net（EN） 0.382 4.193 3.500 0.252 4.846 3.701 Multiple Linear Regression （MLR） 0.382 4.193 3.497 0.247 4.860 3.700 Support Vector Regression (SVR) 0.564 3.518 2.696 0.514 3.860 3.053 Multi Layer Perceptron(MLP) 0.536 3.612 2.945 0.507 3.872 3.145 Extreme Gradient Boosting （XGBoost） 0.826 2.017 1.591 0.572 3.589 2.835 Gradient Boosting Decision Tree（GBDT） 0.772 2.520 2.016 0.567 3.613 2.857 Extreme Trees（ET） 0.791 2.370 1.881 0.560 3.640 2.873