信用評等產業問題之探討

無論資本計提或業務推展，銀行業仰賴信用評等來評估風險，是簡單且易於執行的策略，但需建立在具高度準確性的信評結果前提，才可能會有良好成效。然而深究2008年金融海嘯起因，乃是自2007 年美國房市泡沫化，促使以次級房貸為基礎而發行具投資級的資產證券，接連發生違約情事，當時市場普遍認為，信評機構的「評等膨脹」是造成金融危機的主原因之一。是以本研究將透過瞭解信評服務機制運作、信評產業發展與相關文獻，探究信評結果不準確的因素為何，同時探討在現行機制不變下，發行公司、信用評等機構與投資人三者間須由何者承擔不準確信評結果衍生的外部成本、投資人充分信賴信評結果或不信賴信評結果，又將對信評市場造成何種影響，以及對信評機構相關監理措施，是否足以防範下一次金融危機的發生。

關鍵字

信用評等；評等膨脹；金融危機；信評產業；監理措施

並列摘要

Regardless of capital adequacy calculation or business development, banking relies on credit ratings to assess risk, which is a simple and easy-to-execute strategy, but it needs to be based on highly accurate credit rating results before they can be effective. However, a deep look at the causes of the 2008 financial tsunami was the housing bubble in the United States since 2007, which prompted the issuance of investment-grade asset securities based on subprime mortgages, followed by successive defaults. The market generally believed that the "rating inflation" of credit rating agencies was one of the main causes of the financial crisis. This study will explore the factors of inaccurate credit rating results by understanding the operation of the credit rating service, the development of the credit rating industry and related literature. Under the current model, the issuer, credit rating agencies or investors who should bear the external costs derived from the results of the inaccurate rating. Investors fully trust the results of the credit rating or do not trust the results of the credit rating, and what impact will it have on the credit rating market. As well as the relevant regulatory measures of credit rating agencies, whether it is enough to prevent the next financial crisis.