Interpretable Machine Learning Model for Default Risk Identification of Corporate Bonds

doi:10.3778/j.issn.1002-8331.2310-0298

Abstract

Abstract: Against the backdrop of the gradually exposed credit bond default risk in China, how to accurately identify and efficiently warn of corporate bond default risk has become a key concern for both academia and practice. To effectively solve a series of key problems in the traditional credit risk warning model, such as insufficient warning performance, single optimization target of hyperparameters, and weak model interpretability, this study integrates machine learning algorithms such as LightGBM, NSGA-II, and SHAP to constructs a LightGBM-NSGA-II-SHAP for early warning of corporate bond default risk, and empirically analyzes and tests the warning performance of the proposed model. The research results show that the warning accuracy of the proposed model exceed 85%, and compared with traditional machine learning models, the warning performance of the proposed model in this study is more excellent. In addition, the impact of visualization of warning features on warning results is demonstrated through the SHAP algorithm, and it is found that coupon interest rate, profit margin on fixed assets, total issuance, and receivable turnover etc. are the key features for identifying corporate bond defaults.

Key words: bond default, risk identification, machine learning

摘要： 在我国信用债违约风险不断积累的背景下，如何精准识别、高效预警企业债券违约风险成为学术界及实务界所重点关注的问题。为有效解决传统违约风险预警模型存在的预警性能不强、超参数优化目标单一以及模型可解释性较弱等关键问题，通过有机融合LightGBM、NSGA-II、SHAP等机器学习算法，构建了LightGBM-NSGA-II-SHAP企业债券违约风险预警模型，并通过实证分析检验了所提出模型的预警性能。研究结果表明，所提出模型的预警准确率达到85%以上，相比传统机器学习模型，所提出模型的预警性能更加优异。另外，通过SHAP算法可视化展示预警特征对于预警结果的影响，发现票面利率、固定资产净利润率、发行总额、应收账款周转率等是识别企业债券违约的关键特征。

关键词: 债券违约, 风险识别, 机器学习

DENG Shangkun, NING Hong, LIU Zonghua, ZHU Yingke. Interpretable Machine Learning Model for Default Risk Identification of Corporate Bonds[J]. Computer Engineering and Applications, 2024, 60(12): 334-345.

邓尚昆, 宁宏, 刘宗华, 朱应可. 企业债券违约风险识别的可解释机器学习模型研究[J]. 计算机工程与应用, 2024, 60(12): 334-345.

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