Ashcraft, Adam B.; Goldsmith-Pinkham, Paul; Vickery, James - 2010
We study credit ratings on subprime and Alt-A mortgage-backed-securities (MBS) deals issued between 2001 and 2007, the … period leading up to the subprime crisis. The fraction of highly rated securities in each deal is decreasing in mortgage … standards around the MBS market peak between the start of 2005 and mid-2007. Conditional on initial ratings, we observe …