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 … credit risk (measured either ex ante or ex post), suggesting that ratings contain useful information for investors. However … standards around the MBS market peak between the start of 2005 and mid-2007. Conditional on initial ratings, we observe …