An expansion in mortgage credit to subprime borrowers is widely believed to have been a principal driver of the 2002-06 U.S. house price boom. Contrary to this belief, we show that the house price and subprime booms occurred in different places. Counties with the largest home price appreciation...

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 credit risk (measured either ex ante or ex post),...

We describe and evaluate the measures taken by the U.S. government to rescue Fannie Mae and Freddie Mac in September 2008. We begin by outlining the business model of these two firms and their role in the U.S. housing finance system. Our focus then turns to the sources of financial distress that...

We describe and evaluate the measures taken by the U.S. government to rescue Fannie Mae and Freddie Mac in September 2008. We begin by outlining the business model of these two firms and their role in the U.S. housing finance system. Our focus then turns to the sources of financial distress that...

We summarize and evaluate Fannie Mae and Freddie Mac's credit risk transfer (CRT) programs, which have been used since 2013 to shift a portion of credit risk on more than $1.8 trillion of mortgages to private sector investors. We argue that the CRT programs have been successful in reducing the...