Nonbanks originated about half of all mortgages in 2016, and 75 percent of the mortgages insured by the FHA and the VA. Both shares are much higher than those observed at any point in the 2000s. In this paper, we describe how nonbank mortgage companies are vulnerable to liquidity pressures in both their loan origination and servicing activities, and we document that this sector in the aggregate appears to have minimal resources to bring to bear in an adverse scenario. We show how the same liquidity issues unfolded during the financial crisis, leading to the failure of many nonbank companies, requests for government assistance, and harm to consumers. The high share of nonbank lenders in FHA and VA lending suggests that the government has significant exposure to the vulnerabilities of nonbank lenders, but this issue has received very little attention in the housing reform debate. M ost narratives of the housing and mortgage market crash in the late 2000s attribute it to house price declines, weak underwriting, and other factors that caused credit losses in the mortgage system. The Financial

Nonbanks originated about half of all mortgages in 2016, and 75% of mortgages insured by the FHA or VA. Both shares are much higher than those observed at any point in the 2000s. We describe in this paper how nonbank mortgage companies are vulnerable to liquidity pressures in both their loan origination and servicing activities, and we document that this sector in aggregate appears to have minimal resources to bring to bear in a stress scenario. We show how these exact same liquidity issues unfolded during the financial crisis, leading to the failure of many nonbank companies, requests for government assistance, and harm to consumers. The extremely high share of nonbank lenders in FHA and VA lending suggests that nonbank failures could be quite costly to the government, but this issue has received very little attention in the housing-reform debate.

We study impacts of advertising as a channel of risk selection in Medicare Advantage. We show evidence that both mass and direct mail advertising are targeted to achieve risk selection. We develop and estimate an equilibrium model of Medicare Advantage with advertising to understand its equilibrium impacts. We find that advertising attracts the healthy more than the unhealthy. Moreover, shutting down advertising increases premiums by up to 40% for insurers that advertised by worsening their risk pools, which further reduces the demand of the unhealthy. We argue that risk selection may make consumers better off by improving insurers' risk pools.

The U.S. government guarantees a majority of residential mortgages, which is often justified as a means to promote homeownership. In this paper we use property-level data to estimate the effect of government mortgage guarantees on homeownership, by exploiting variation of the conforming loan limits (CLLs) along county borders. We find substantial effects on government guarantees, but find no robust effect on homeownership. This finding suggests that government guarantees could be considerably reduced with modest effects on homeownership, which is relevant for housing finance reform plans that propose to reduce the government's involvement in the mortgage market by reducing the CLLs.