Private Mortgage Securitization and Loan Origination Quality - New Evidence from Loan Losses Abdullah Yavas Robert E. Wangard Chair School of Business University of Wisconsin - Madison Madison, WI 53706
[email protected] and Shuang Zhu Associate Professor Department of Finance Kansas State University Manhattan, KS 66506
[email protected] December 11, 2018 1 Private Mortgage Securitization and Loan Origination Quality - New Evidence from Loan Losses Abstract Due to data constraints, earlier studies of the impact of securitization on loan quality have used default probability as a proxy for loan quality. In this paper, we utilize a unique data set that allows us to use loan losses, which incorporate both probability of default and loss given default, to proxy for mortgage quality. Our analysis of prime loans shows that higher expected loan losses are associated with higher probability of securitization. Lenders sell prime loans with lower observable quality and keep higher observable quality loans on their books. For subprime loans, we observe opposite results that lenders sell better quality loans and keep lower quality loans on their book. We then use the cutoff FICO score of 620 to infer the lender’s screening effort with respect to unobservable loan quality. We find that securitized prime loans exhibit no significant difference in default losses for 620- versus 620+ loans. However, securitized subprime loans with a 620- score incur significantly lower loan losses than securitized subprime loans with a 620+ score. By using loan losses as the proxy of loan quality, separating the analysis into prime and subprime samples, and distinguishing between observable and unobservable risk characteristics, this study sheds additional light on the potential channels that the securitization affects loan quality.