整合存量與流量模型之結構型信用風險模型

An Integrated Structural form Credit Risk Model ---A Combination of Stock- and Flow-based Credit Risk Models

盧嘉梧(Chia-Wu Lu)

指導教授 ： 廖咸興

國立臺灣大學/管理學院/財務金融學研究所/博士(2009年)

https://doi.org/10.6342/NTU.2009.10024

摘要

本研究建立一個整合存量基礎與流量基礎的結構型企業信用風險評估模型。與傳統結構型模型不同點在於，傳統結構型模型僅考慮存量基礎的違約（資產不足以抵償債務）風險，而本研究模型則同時考慮存量基礎的違約型態，以及流量基礎的違約（流動性償付不能）風險，並可內生化地決定企業未來的違約機率。經由數值分析的結果顯示，相對於傳統Merton形式的存量基礎模型傾向於低估短期違約機率，本研究模型具有較能捕捉短期的違約風險之特點；此外，實際應用本模型於評估樣本銀行之違約風險，亦顯示本模型能增進短期違約機率評估之有效性。

關鍵字

存量基礎信用風險模型 ； 流量基礎信用風險模型 ； 償付不能

並列摘要

This study develops an integrated structural-form credit risk model which combines both stock-based and flow-based corporate credit information. The new model differs from traditional structural-form credit models in that it considers not only stock-based default but also flow-based insolvency. This model can generate endogenously a firm’s probabilities of default, resulting from either asset inadequacy or liquidity crunch. Numerical analyses show that the model can catch short-term default risk which is underestimated by traditional Merton-type stock-based models. An application to a bank sample shows that this model is able to improve the effectiveness for evaluating short-term default probabilities.

並列關鍵字

Stock-based Credit Model ； Flow-based Credit Model ； Flow-based Insolvency

參考文獻

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