The aim of this paper is to explain why cross-sectional estimated migration correlations displayed in the academic and professional literature can be either not consistent, or inefficient, and to discuss alternative approaches. The analysis relies on a model with stochastic migration in which...

This paper examines latent risk factors in models for migration risk. We employ thestandard statistical framework for ordered categorical variables and induce dependencebetween migrations by means of latent risk factors. By assuming a Markov process forthe dynamics of the latent factors, the...

The dynamic analysis of corporate credit ratings is needed for predicting the risk included in a credit portfolio at different horizons. In this paper, we present the estimation of an ordered probit model with factors for the migration probabilities, with its application to aggregate data...

We consider a set of Markovian processes with Stochastic transition matrices. This specification extends the standard stochastic intensity model introduced by Cox in the two state case. Such a model is appropriate for the joint analysis of rating histories of several corporates, including the...

The aim of this paper is to explain why cross-sectional estimated migration correlations displayed in the academic and professional literature can be either not consistent, or inefficient, and to discuss alternative approaches. The analysis relies on a model with stochastic migration in which...

In this paper we shed more light on the portfolio behaviour of the older part of the UK population over the period 1988-94. We employ data from the Retirement Survey and different econometric specifications in order to model the risky asset ownership decisions over time. The unique nature of the...

Information on the expected changes in credit quality of obligors is contained in credit migration matrices which trace out the movements of firms across ratings categories in a given period of time and in a given group of bond issuers. The rating matrices provided by Moody’s, Standard...

This paper uses the market-standard Gaussian copula model to show that fair spreads on CDO tranches are much higher than fair spreads on similarly-rated corporate bonds. It implies that credit ratings are not sufficient for pricing, which is surprising given their central role in structured...

Starting from the Merton framework for firm defaults, we provide theanalytics and robustness of the relationship between defaultprobabilities and default correlations. We show that loans with higherdefault probabilities will not only have higher variances but also highercorrelations with other...

Since 2011, Morningstar has issued Morningstar Analyst Ratings on many of the largest mutual funds in the United States. In June 2017, Morningstar launched the Morningstar Quantitative Rating™ to provide a forward‐looking rating on all mutual funds. Morningstar uses a “robo‐rater”...