Severe Loss Probabilities in Portfolio Credit Risk Models

Babbs, Simon H and Johnson, Andrew E (1999): Severe Loss Probabilities in Portfolio Credit Risk Models.

Abstract

We derive explicit sharp bounds on the distribution of the number of defaults from a pool of obligors with common probability of default and default correlation. These bounds are extremely wide, implying that default probabilities and default correlations only very loosely determine probabilities of severe portfolio losses. Our results quantify and thereby reinforce Gordy’s (2002) statement that “Capital decisions ... depend on higher moments”.

• Item Type: MPRA Paper
• Language: English
• Keywords: Portfolio Credit Risk Models
• Subjects: G - Financial Economics > G1 - General Financial Markets > G11 - Portfolio Choice ; Investment Decisions; G - Financial Economics > G3 - Corporate Finance and Governance > G31 - Capital Budgeting ; Fixed Investment and Inventory Studies ; Capacity

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