Abstract This article provides a comprehensive history of default risk for newly originated home mortgages in the USA over past quarter century. The loan-level source data include entire guarantee book Fannie Mae and Freddie Mac. We track many loan characteristics produce summary measure risk. Among our results, we show that mortgage had already risen 1990s, planting seeds financial crisis well...

A linear regression of y on x can be approximated by a simple difference: the average values of y corresponding to the highest quarter or third of x, minus the average values of y corresponding to the lowest quarter or third of x. A simple theoretical analysis shows this comparison performs reasonably well, with 80%–90% efficiency compared to the linear regression if the predictor is uniformly ...

We introduce and study (metrically) quarter-stratifiable spaces and then apply them to generalize Rudin and Kuratowski-Montgomery theorems about the Baire and Borel complexity of separately continuous functions. The starting point for writing this paper was the desire to improve the results of V.K. Maslyuchenko et al. [MMMS], [MS], [KM], [KMM] who generalized a classical theorem of W.Rudin [Ru]...