Rating downgrades are known to make subsequent downgrades more likely. We analyze the impact of this 'downward momentum' on credit portfolio risk. Using S&P ratings from 1996 to 2005, we estimate a transition matrix that is insensitive to and a second matrix that is sensitive to previous...

Measuring and displaying uncertainty around path-forecasts, i.e. forecasts made in period T about the expected trajectory of a random variable in periods T+1 to T+H is a key ingredient for decision making under uncertainty. The probabilistic assessment about the set of possible trajectories that...

In this paper, we investigate the implications of the two concepts of asymmetry defined by Sichel (1993) - deepness and steepness - for first-order autoregressive processes with a Markov-switching intercept. In order to do so, we derive the two required formulas determining the coefficient of...