This paper provides an overview on classical and new methods for testing time series properties of migration matrices. It is well known that due to cyclical behaviour of the economy transition matrices for many credit portfolios cannot be considered to be constant through time. Further,...

In this paper, we show the importance of accounting for heterogeneity among sample firms in stochastic frontier analysis. For a fairly homogenous sample of German savings and cooperative banks, we analyze how alternative theoretical assumptions regarding the nature of heterogeneity can be...

In credit risk management migration matrices are major inputs for many applications, including the determination of Value-at-Risk or derivative pricing. After reviewing distance measures for migration matrices we motivate and propose new directed difference indices to measure changes in...

Die Rekordzahlen an Unternehmensinsolvenzen, die schlechte Ertragslage der deutschen Kreditinstitute in den vergangenen Jahren und der von Basel II ausgehende Druck zur Verwendung von realitätsnahen Ausfallwahrscheinlichkeiten haben es überdeutlich gemacht: Der Bedarf an leistungsfähigen...

We analyse a sample of funds and other securities each assigned a total rating score by an unknown expert entity. The scores are based on a number of risk and complexity factors, each assigned a category (factor score) of Low, Medium, or High by the expert entity. A principal component analysis...