The good, the bad and the impaired: A credit risk model of the Irish mortgage market

Using a uniquely constructed loan-level dataset of the residential mortgage book of Irish financial institutions, this paper provides a framework for estimating default probabilities of individual mortgages. In contrast to the popular stock delinquency approach, this model provides estimates of default and cure flows: a requirement of the stress test approach adopted by the European Central Bank's comprehensive assessment. In addition, both default and cure transitions are modelled as functions of micro- and macro-covariates including loan characteristics and current macroeconomic conditions such as house prices and unemployment. When comparing the competing equity and affordability effects, labour market deterioration played a stronger role than house equity in the rise of Irish default rates. For cures, a scarring effect of default is identified and estimated with the probability of a loan returning to performing reducing by almost four per cent each month a loan remains delinquent.