Margin of Conservatism Framework for IRB PD, LGD and CCF - Extended with Numerical Example

Abstract

The EBA Guidelines on PD and LGD estimation is due to apply from 1 January 2021, in which the banks are expected to have a framework in place as part of the risk rating and reporting process to adjust and correct the uncertainties identified from deficiencies in data, system and methodology. The ECB Guide on the TRIM in the meantime state that the requirement of Margin of Conservatism (MoC) also applies for the CCF estimation. In this paper, we develop and present a consistent framework to quantify the identified uncertainties for the purpose of IRB risk parameter estimation.

Keywords: Advanced IRB, Long-Run Default Rate, Long-Run LGD, Central Default Tendency, Risk Weighted Assets (RWA), Margin of Conservatism (MoC), Probability of Default (PD), Loss Given Default (LGD), Credit Conversion Factor (CCF), Exposure at Default (EAD)