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A novel model for hourly PM2.5 concentration prediction based on CART and EELM
Zhigen Shang1, Tong Deng2, Jianqiang He1
1Department of Automation, Yancheng Institute of Technology, Yancheng 224051, China.
This study introduces a novel hierarchical model using Classification and Regression Trees (CART) and Ensemble Extreme Learning Machines (EELM) for accurate hourly PM2.5 concentration prediction. The model effectively addresses the global-local duality, outperforming existing methods.
Area of Science:
- Environmental Science
- Data Science
- Machine Learning
Background:
- Hourly PM2.5 concentrations exhibit complex, multi-pattern changes.
- Accurate prediction requires localized models but faces challenges with global-local duality.
Purpose of the Study:
- To develop a novel hierarchical prediction model for hourly PM2.5 concentrations.
- To address the global-local duality inherent in localized prediction methods.
Main Methods:
- A hybrid approach combining Classification and Regression Trees (CART) for hierarchical data splitting.
- Ensemble Extreme Learning Machines (EELM) are trained at each node and leaf of the CART-generated tree.
- Model selection at each leaf considers both global and path-specific local EELM models.
Main Results:
- The developed CART-EELM model effectively handles multiple change patterns in PM2.5 data.
- It demonstrates superior performance compared to global models (Random Forest, v-SVR, EELM) and traditional local models (season, k-means).
- The method successfully resolves the global-local duality issue.
Conclusions:
- The novel hierarchical CART-EELM model offers improved accuracy for hourly PM2.5 prediction.
- This approach enhances the capability to model complex air pollutant concentration dynamics.
- The study provides a robust framework for environmental data prediction challenges.
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