基于机器学习的交通碳排放预测模型构建与分析

针对交通运输碳排放问题,基于2005~2019年30个省份的面板数据,采用多种机器学习算法构建不同预测模型对30个省份的交通碳排放量与影响因素进行分析.首先,基于固定效应模型思想将省份差异转化为影响因素,进一步采用Pearson相关系数法与Spearman秩相关系数相结合的方法对18个交通碳排放影响因素进行筛选；其次,采用K-折交叉验证方法,并绘制学习曲线对各预测模型性能进行测试,选用MSE、MAE、R²和MAPE作为模型的评价指标进行分析,来选定最佳预测模型,并选择SHAP值来计算最佳预测模型中各解释变量的重要度.结果表明,省份差异、社会商品消费总额、城市绿地面积、货运周转量、私家车数量、交通运输业产值和常住人口这7个因素之间多重共线性弱且均通过显著性检验,可作为交通运输碳排放预测模型的解释变量；随机森林算法和XGBoost算法预测结果均表现优异,R²均高于0.97,误差均低于10 %,且不存在过拟合与欠拟合现象,其中XGBoost算法表现最优,而KNN算法表现欠佳；各解释变量的重要度排名为:省份差异 > 社会商品消费总额 > 私家车数量 > 常住人口 > 货运周转量 > 城市绿地面积 > 交通运输业产值, 综合相关性与重要性分析来看,在交通运输碳排放预测中,省份差异是一个不可忽视的变量.研究结果可为政策制定者和决策者提供参考,促进交通运输行业的可持续发展.

Construction and Analysis of Machine Learning Based Transportation Carbon Emission Prediction Model

Addressing the issue of carbon emissions in the transportation sector, this research constructed various predictive models using multiple machine learning algorithms based on panel data from 30 provinces in China from 2005 to 2019. The study aimed to identify the optimal machine learning algorithm and key factors influencing the carbon emissions of transportation, providing potent references for policymakers and decision-makers to reduce carbon emissions and promote the sustainable development of the transportation sector. Initially, drawing from the concept of the fixed effects model, we included the heterogeneity differences among provinces as an important factor. We further employed a combined method of Pearson''s correlation coefficient and Spearman''s rank correlation coefficient to screen 18 factors influencing transportation carbon emissions. We then made a preliminary selection of seven common machine learning algorithms and used the screened factors as explanatory variables for model training. The three algorithms with the best performance were further optimized and trained. Subsequently, we utilized the K-fold cross-validation method; plotted learning curves to test the performance of each predictive model; and used MSE, MAE, R², and MAPE as evaluation indicators to determine the best predictive model. SHAP values were chosen to calculate the importance of each explanatory variable in the optimal predictive model. The results indicated that the multicollinearity among the seven factors of provincial differences, total consumption of social goods, urban green space area, freight turnover, number of private cars, transportation industry output, and permanent population was weak, and all passed the significance test. They could be used as explanatory variables in the prediction model of transportation carbon emissions. The prediction results of the Random Forest and XGBoost algorithms were both outstanding, with R² values above 0.97 and errors below 10 %, showing no signs of overfitting or underfitting. Among them, the XGBoost algorithm performed the best, whereas the KNN algorithm performed poorly. The importance ranking of the explanatory variables was as follows:provincial differences > total consumption of social goods > number of private cars > permanent population > freight turnover > urban green space area > transportation industry output. A comprehensive analysis of relevance and importance showed that provincial differences were an indispensable variable in the prediction of transportation carbon emissions. In conclusion, this study provides a new approach to the governance of carbon emissions in the transportation industry, and the results can serve as a reference for policymakers and decision-makers. In future policy design and decision-making, the distinctive factors of each province should not be overlooked. Measures targeted at specific regions need to be formulated to promote the sustainable development of the transportation industry.