Journal of Banking Regulation

, Volume 20, Issue 4, pp 341–347 | Cite as

The disparity in PD and LGD estimates within the IRB framework and prospects for future improvement

  • Patricia Stupariu
  • Juan Rafael RuizEmail author
  • Ángel Vilariño
Original Article


The internal ratings-based approach (IRB) to calculating capital requirements for credit risk was the main novelty brought about by Basel II and remains fundamentally unchanged in Basel III. The adequacy of this framework has been controversial since its inception, but throughout the years, most regulators and the banking industry have remained among its strong supporters. This paper focuses on some of the most problematic elements of the IRB approach, concerning the estimation of the main parameters capital requirements depend on and the difficulty embedded in the validation process. In the light of these difficulties, it concludes maintaining the IRB approach in its current form and scope reflects an overly optimistic stance with respect to financial institutions’ ability to accurately estimate critical risk parameters and prospects for future improvements.


Basel IRB LGD Credit Risk Financial Regulation 



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Copyright information

© Springer Nature Limited 2019

Authors and Affiliations

  • Patricia Stupariu
    • 1
  • Juan Rafael Ruiz
    • 1
    • 2
    Email author
  • Ángel Vilariño
    • 1
  1. 1.Instituto Complutense deEstudios InternacionalesUniversidad Complutense deMadridMadridSpain
  2. 2.Universidad Metropolitana del EcuadorQuitoEcuador

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