Mortgage default in an estimated model of the U.S. housing market

This paper models the housing sector, mortgages and endogenous default in a DSGE setting with nominal and real rigidities. We use data for the period 1981–2006 to estimate our model using Bayesian techniques. We analyze how an increase in risk in the mortgage market raises the default rate and spreads to the rest of the economy, creating a recession. In our model two shocks are well suited to replicate the subprime crisis and the Great Recession: the mortgage risk shock and the housing demand shock. Next we use our estimated model to evaluate a policy that reduces the principal of underwater mortgages. This policy is successful in stabilizing the mortgage market and makes all agents better off.     

Subprime mortgages and the housing bubble

This paper explores the link between the house-price expectations of mortgage lenders and the extent of subprime lending. It argues that bubble conditions in the housing market are likely to spur subprime lending, with favorable price expectations easing the default concerns of lenders and thus increasing their willingness to extend loans to risky borrowers. Since the demand created by subprime lending feeds back onto house prices, such lending also helps to fuel an emerging housing bubble. These ideas are illustrated in a theoretical model, and tentative support is found in empirical work exploring the connection between price expectations and the extent of subprime lending.     

Spillover effects of subprime mortgage originations: The effects of single-family mortgage credit expansion on the multifamily rental market

The dramatic expansion in subprime mortgage credit fueled a remarkable boom and bust in the US housing market and created a global financial crisis. Even though considerable research examines the housing and mortgage markets during the previous decade, how the expansion in mortgage credit affected the rental market remains unclear; and yet, over 30 percent of all U.S. households reside in the rental market. Our study fills this gap by showing how the multifamily rental market was adversely affected by the development of subprime lending in the single-family market before the advent of the 2007/2008 subprime induced financial crisis. We provide evidence for a fundamentals based linkage by which the effect of an innovation in one market (i.e, the growth in subprime mortgage originations) is propagated through to another market. Using a large database of residential rental lease payment records, our results confirm that the expansion in subprime lending corresponds with an overall decline in the quality of rental payments. Finally, we present evidence showing that the financial performance of multifamily rental properties reflected the increase in rental lease defaults.     

Subprime lending over time: the role of race

In light of the increased scrutiny of the subprime market nationally and the concerns raised that low- and moderate-income and minority homeowners are targeted for high-cost loans, this paper examines the extent to which subprime lending occurs in selected states and the role that race plays in obtaining prime versus subprime loans. It focuses on explaining the gap in subprime rates between African–Americans and whites and estimating its change over time (1999 to 2006) for the study states. We use a unique data set comprised of data from several data sources, including loan-level information, which allows for better controls over factors correlated with race so that better inferences can be drawn. Also, an estimating procedure is employed that fine-tunes the influence of race in the allocation of mortgage capital between the prime and subprime markets. After taking into accounts various controls, the results suggest the possibility of bias in mortgage lending for the prioed studied.     

美国次贷危机及对中国的启示

介绍了美国次级抵押贷款市场的演变,对此次次级抵押贷款市场危机爆发的诱因进行了详细探讨,同时结合中国住房抵押贷款市场的现状,对中美两国住房抵押贷款市场之间的相同及差异点进行比较分析,指出中国政府在防范住房抵押贷款风险方面应该予以重点关注的几个领域。     

Renter Mobility and Multifamily Mortgage Default Risk

Renter mobility is a major concern for the performance of multifamily mortgages. If enough new renters are not found to replace those that move, vacancy rates can quickly escalate to where cash flows are negative and property mortgages are in jeopardy. In this study we examine how differences in renter mobility patterns by property type can affect mortgage credit risk within submarkets of an MSA. We expand the default model developed by Goldberg and Capone (2000) to use unique distributions of rental unit turnover and vacancy durations for large and small multifamily rental properties. Monte Carlo simulations then show how credit risk on multifamily mortgages is affected if owners of small properties are able to keep tenants longer than owners of larger properties can. The model can be used to explore other potential intra-MSA differences in property market dynamics.     

Credit rationing, race, and the mortgage market

This study applies microdata from the 1983 Survey of Consumer Finances to evaluate the effects of borrower race and default risk in mortgage lending. The empirical analysis is based on a probit model of whether borrowers obtain FHA or conventional mortgages; the former are fully insured and are characterized by easier downpayment constraints, but are typically more expensive. Hence, households borrowing through the FHA will tend to be credit constrained in the conventional market. Results of the analysis indicate that variables which proxy lender concerns about default risk and cost have an important effect on the type of loan borrowers obtain. Empirical estimates also suggest that minority households are significantly less likely to obtain conventional financing than whites, even after controlling for various proxies of default risk. These results suggest that race effects in mortgage lending may persist for reasons unrelated to borrower default risk.     

Commercial mortgage underwriting: How well do lenders manage the risks?

Loan-to-value ratio and debt service coverage ratios have long been viewed as the two most important quantitative measures of the default risk of commercial mortgages. Option-based models of default provide strong theoretic support for the importance of original loan-to-value ratio. The same theoretical predictions have found strong empirical support in residential single-family mortgage analyses. However, recent empirical studies of commercial mortgage default have raised questions about the role of loan-to-value ratio in assessing the riskiness of commercial mortgages. These studies generally either find no relationship or a puzzling negative relationship between loan-to-value ratio and default. This paper uses a very large database of commercial loan histories to thoroughly investigate this issue. It finds strong evidence that loan-to-value and debt service coverage ratios are endogenous to the underwriting process. Lenders react to other—unmeasured—risk factors with credit rationing and pricing. As a result, unusually low loan-to-value ratio loans appear to have above average risk in other dimensions and their default probabilities are equal to or higher than average. The results show that the pricing spread that lenders establish as part of the underwriting process serves as an excellent summary measure of the riskiness of the loan. A test of lenders’ ability to appropriately price loan-to-value risk finds that, while there is some unpriced effect of loan-to-value ratio after controlling for the lender’s pricing, introducing lender pricing into the model removes the otherwise puzzling negative loan-to-value and default relationship previously observed in the literature.     

An analysis of default risk in the Home Equity Conversion Mortgage (HECM) program

While reverse mortgages are intended as a tool to enable financial security for older homeowners, in 2014, nearly 12 percent of reverse mortgage borrowers in the federally insured Home Equity Conversion Mortgage (HECM) program were in default on their property taxes or homeowners insurance. Unlike the traditional mortgage market, there were no risk-based underwriting guidelines for HECMs through 2014. In response to the relatively high default rate, a variety of policy responses were implemented, including establishing underwriting guidelines. However, there is a lack of data and analysis to inform such criteria. Our analysis follows 30,000 seniors counseled for reverse mortgages between 2006 and 2011. The data includes comprehensive financial and credit report attributes, not typically available in analyses of reverse mortgage borrowers. Using a bivariate probit model that accounts for selection, we estimate the likelihood of tax and insurance default. Financial characteristics that increase default risk include the percentage of funds withdrawn in the first month of the loan, a lower credit score, higher property tax to income ratio, low or no unused revolving credit, and a history of being past due on mortgage payments or having a tax lien on the property. Our estimate of the elasticity of default with respect to credit scores is similar to that for closed-end home equity loans, but higher than that for HELOCs. We simulate the effects of alternative underwriting criteria and policy changes on the probability of take-up and default. Reductions in the default rate with a minimal effect on participation can be achieved by requiring that participants with low credit scores set aside some of their HECM funds for future property tax and insurance payments, a form of escrowing.     

住房抵押贷款借款人违约风险影响因素及应对措施研究

随着房地产业的快速发展,个人住房抵押贷款已经成为商业银行的重要业务.然而,面对日趋复杂多变的市场环境,违约风险的隐患也日益显现.本文就国内外有关违约风险影响因素的研究进行了综述,指出以往研究的局限性,并结合我国实际提出了控制违约风险的建议和对策.     

商业银行市场风险预警体系构建及实证分析

2008年爆发的美国次贷危机暴露了商业银行市场风险预警的缺失。本文从宏观和微观两个层面选取12个市场风险预警指标,并结合因子分析方法,对中国商业银行市场风险预警体系进行实证研究,为商业银行市场风险管理实践提供理论指导。     

Spillover effects in oil-related CDS markets during and after the sub-prime crisis

This paper investigates the return and volatility spillover effects across oil-related credit default swaps (CDSs), the oil market, and financial market risks for the US during and after the subprime crises. The empirical analysis is based on monthly return and realized volatility data from February 2004 to April 2020. We estimate both static and dynamic generalized dynamic spillover measures based on vector autoregressive (VAR) models. Our full sample empirical findings show that the oil market is the primary source of risk transmission for all the oil-related credit default swaps, while the bond market is the highest source of risk transmission to the stock market and vice versa. We also provide evidence that the regulated monopoly US utility sector has the least role in volatility transmission. Furthermore, the bailout program conducted by the US Treasury and Federal Reserve helped stabilize the US financial market through the purchase of toxic assets after the subprime financial crisis. We find strong evidence that the federal funds rate hike cycles lessen total risk transmission throughout the US bond market. Finally, our findings assert that oil price shocks have a significant effect on the oil-related CDSs in some sub-periods via the demand and supply transmission channels.     

Reconciling theory and empirics on the role of unemployment in mortgage default

Empirical models of mortgage default typically find that the influence of unemployment is negligible compared to other well known risk factors such as high borrower leverage or low borrower FICO scores. This is at odds with theory, which assigns a critical role to unemployment in the decision to stop payment on a mortgage. We help reconcile this divergence by employing a novel empirical strategy involving simulated unemployment histories to measure the severity of attenuation bias in loan-level estimations of default risk due to a borrower becoming unemployed. Attenuation bias results because individual data on unemployment status is unobserved, requiring that a market-wide unemployment rate be used as a proxy. Attenuation is extreme, with our results suggesting that the use of an aggregate unemployment rate in lieu of actual borrower unemployment status results in default risk from a borrower becoming unemployed being underestimated by a factor more than 100. In addition, our analysis indicates that adding the unemployment rate as a proxy for the missing borrower-specific unemployment indicator does not improve the accuracy of the estimated model over the specification without the proxy variable included. Hence, aggregate portfolio-level risk estimates for mortgage guarantors such as FHA also are not improved.These views represent those of the authors and not necessarily those of the Federal Reserve Bank of New York or the Federal Reserve System. This is a revised version of a paper that previously circulated under the title “Unemployment and Unobserved Credit Risk in the FHA Single Family Mortgage Insurance Fund (NBER Working Paper No. 18880). John Grigsby provided excellent research assistance. We appreciate the helpful comments of Andrew Haughwout, Wilbert van der Klaauw, the editor (Stuart Rosenthal) and referees, but remain responsible for any errors.     

Extracting market information from equity options with exponential Lévy processes

Lévy processes have been successfully applied in the modeling of financial assets. Useful information such as implied volatility, skewness, and risk-preferences can be derived from market option prices. In this paper, we advocate using Esscher conjugate Lévy processes to estimate risk-neutral and empirical densities. More specifically, we employ the exponential Meixner and NIG processes to calculate in closed form the pricing kernel in the equity market and then study the evolution of equity market behavior between 2002 and 2010. Our empirical analysis using S&P 500 options shows that the risk preferences of equity investors were signalling an anomaly in the market well before the subprime prime mortgage crisis (August 2007) and the crisis of confidence that followed, anticipating the downfall in equity markets in 2008, but then returning to normal levels in 2009.     

后金融危机时代房地产金融创新与风险防范

由美国次贷危机引发的全球金融危机深刻展现了房地产金融创新的现实风险,住房贷款供需两旺的繁荣背后,商品房价的高位运行足以引起我们对房地产市场风险的重视,以加快金融创新,增强防范意识和能力。     

波动和相关的一致性与差异及传染的阶段特征

本文首次分析了市场波动和相关的一致性与差异,并进而考察金融危机期间传染的阶段特征。研究表明,危机期间,高波动与高相关具有较高的一致性,其他时期则存在差异;几乎不会出现高波动低相关的情形,但并非总是波动性的增加引致了关联水平的上升,关联水平的上升也可能会先于波动性的增加;危机初期,市场需要对复杂的信息进行不断地识别和过滤,以至于波动机制、相关机制都存在较为频繁的转换;次贷危机、欧洲主权债务危机的传染具有系统性特征。     

Volatility contagion: A range-based volatility approach

This article proposes a new approach to evaluate volatility contagion in financial markets. A time-varying logarithmic conditional autoregressive range model with the lognormal distribution (TVLCARR) is proposed to capture the possible smooth transition in the range process. Additionally, a smooth transition copula function is employed to detect the volatility contagion between financial markets. The approach proposed is applied to the stock markets of the G7 countries to investigate the volatility contagion due to the subprime mortgage crisis. Empirical evidence shows that volatility is contagious from the US market to several markets examined.     

Payment shock and mortgage performance

The effect of payment shocks on subprime hybrid ARM mortgage prepayment and delinquency is examined. Using loan level data from private label securities, we modeled the effects of payment shocks on mortgage performance. Our study provided interesting empirical results in three main areas: First, we addressed the effect of payment shocks on subsequent mortgage delinquency. Second, we studied how the effect of payment shocks varies and decays over time. Third, we disentangled the impact of payment shocks based on the reason for the shocks: payment shock due to the expiration of a teaser rate (i.e. “teaser shock”) versus the payment shock due to index rate changes at the time of reset (i.e. “market rate shock”).We find that the effect of payment shock on loan performance varies by the delinquency status of the loan at the time of the shock. That is, the payment shock has the most significant effect on “current” loans rather than loans already in delinquency. Also of note, we find that the effect of a payment shock decays only gradually over time. We find that the impact of “teaser shocks” and “market rate shocks” on mortgage performance do not differ substantially, even though teaser shocks may be somewhat more predictable than market rate shocks. This suggests that either subprime ARM borrowers did not fully understand the product and the extent of the shock at the first reset date or that financially strapped borrowers used the product to speculate and were caught by the teaser shock when they were unable to refinance or sell (i.e. “flip”) their properties .The study suggests that any modification plan designed to eliminate potential payment shocks or to otherwise lower payments will be most effective for loans that are currently performing rather than loans that are already in delinquency.     

Analyzing yield, duration and convexity of mortgage loans under prepayment and default risks

In this article, we construct a general model, which considers the borrower’s financial and non-financial termination behavior, to derive the closed-form formula of the mortgage value for analyzing the yield, duration and convexity of the risky mortgage. Since the risks of prepayment and default are reasonably expounded in our model, our formulae are more appropriate than traditional mortgage formulae. We also analyze the effects of the prepayment penalty and partial prepayment on the yield, duration and convexity of a mortgage, and provide lenders with an upper-bound for the mortgage default insurance rate. Our model provides portfolio managers a useful framework to more appropriately appraise the mortgage and more effectively hedge their mortgage holdings. From the results of sensitivity analyses, we find that higher interest-rate, prepayment and default risks will increase the mortgage yield and reduce the duration and convexity of the mortgage.     

美国次贷危机对我国住房金融的启示

本文从美国次贷危机的形成着手分析其产生的背景,剖析其风险积累过程,进而阐述该危机对美国经济乃至世界经济和中国的影响,并结合日本金融泡沫破裂的教训,总结对我国住房金融发展的启示。