A duration dependent rating migration model: Real data application and cost of capital estimation

This paper presents a duration dependent model for analysing the evolution of credit ratings. It considers the backward recurrence process to tackle the time of permanence problem in the rating classes. In this way it is possible to manage the duration effects, which represent one of the most important features in rating dynamics. Furthermore, the paper shows how it is possible to compute the cost of capital that an organisation is required to pay for the capital used in financing its activities. A real data application using Standard & Poor’s historical database is provided.