This paper studies leverage regulation and monetary policy when equity investors and/or creditors have distorted beliefs relative to a planner. We characterize how the optimal leverage regulation responds to arbitrary changes in investors' and creditors' beliefs and relate our results to...

This paper studies optimal second-best corrective regulation, when some agents/activities cannot be perfectly regulated. We show that policy elasticities and Pigouvian wedges are sufficient statistics to characterize the marginal welfare impact of regulatory policies in a large class of...

This paper studies optimal financial policy in a world where the financial sector can become excessively optimistic. I decompose the welfare effects of bank capital regulation to demonstrate the effects of exuberance and its interaction with incentive problems in banking. The optimal policy...

This paper studies optimal second-best corrective regulation, when some agents/activities cannot be perfectly regulated. We show that policy elasticities and Pigouvian wedges are sufficient statistics to characterize the marginal welfare impact of regulatory policies in a large class of...

Surprisingly little is known about the importance of mortgage payment size for default, as efforts to measure the treatment effect of rate increases or loan modifi cations are confounded by borrower selection. We study a sample of hybrid adjustable-rate mortgages that have experienced large rate...

Fixed-rate mortgages (FRMs) dominate the U.S. mortgage market, with important consequences for household risk management, monetary policy, and systemic risk. In this paper, we show that securitization is a key driver of FRM supply. Our analysis compares the agency and nonagency...

Surprisingly little is known about the importance of mortgage payment size for default, as efforts to measure the treatment effect of rate increases or loan modifications are confounded by borrower selection. We study a sample of hybrid adjustable-rate mortgages that have experienced large rate...

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...

Spreads of agency mortgage-backed securities (MBS) vary significantly in the cross section and over time, but the sources of this variation are not well understood. We document that, in the cross section, MBS spreads adjusted for the prepayment option show a pronounced smile with respect to the...

The sensitivity of housing demand to mortgage rates and available leverage is key to understanding the effect of monetary and macroprudential policies on the housing market. However, since there is generally no exogenous variation in these variables that is independent of confounding factors...