Paul S. Calem

The Neighborhood Distribution of Subprime Mortgage Lending

Subprime lending in the residential mortgage market, characterized by relatively high credit risk and interest rates or fees, has developed over the past decade into a prominent segment of the market (Temkin, 2000). Recent research indicates that there is geographical concentration of subprime mortgages in Census tracts where there are high concentrations of low-income and minority households. The growth in subprime lending represents an expansion in the supply of mortgage credit among households who do not meet prime market underwriting standards. Nonetheless, its apparent concentration in minority and lower income neighborhoods has generated concerns that these households may not be obtaining equal opportunity in the prime mortgage market. Such lending may undermine revitalization to the extent that it is associated with so-called predatory practices.

Risk-based capital requirements for mortgage loans

We develop estimates of risk-based capital requirements for single-family mortgage loans held in portfolio by financial intermediaries. Our method relies on simulation of default and loss probability distributions via simulation of changes in economic variables with conditional default probabilities calibrated to recent actual mortgage loan performance data from the 1990s. Based on simulations with varying input parameters, we find that appropriate capital charges for credit risk vary substantially with loan or borrower characteristics and are generally below the current regulatory standard. These factors may help explain the high degree of securitization, or regulatory capital arbitrage, observed for this asset category.

The Concentration/Conduct Relationship in Bank Deposit Markets

This study investigates the structure/conduct/performance relationship in retail deposit markets. The study explicitly incorporates conduct as the link between structure and performance in local deposit markets. It attempts to determine whether banks typically behave competitively or strategically, and whether their conduct is influenced by market concentration. The empirical investigation is guided by an equilibrium model of a retail deposit market. The model is applied to regression equations for local (MSA) MMDA and three- and six-month CD rates. The empirical results indicate that strategic conduct is the norm in MMDA and in three- and six-month CD markets. Copyright 1991 by MIT Press.

Switching costs and adverse selection in the market for credit cards: New evidence

To explain persistence of credit card interest rates at relatively high levels, Calem and Mester (AER, 1995) argued that informational barriers create switching costs for high-balance customers. As evidence, using data from the 1989 Survey of Consumer Finances, they showed that these households were more likely to be rejected when applying for new credit. In this paper, they revisit the question using the 1998 and 2001 SCF. Further, they use new information on card interest rates to test for pricing effects consistent with information-based switching costs. The authors find that informational barriers to competition persist, although their role may have declined. ; Also issued as Payment Cards Center Discussion Paper No. 05-09

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. The paper, however, focuses on the reverse causal linkage, where subprime lending is a consequence rather than a cause of bubble conditions. These ideas are illustrated in a theoretical model, and empirical work tests for a connection between price expectations and the extent of subprime lending.

Branch Banking and the Geography of Bank Pricing

We show that bank branching tends to mitigate localized market power by broadening the geographic scope of competition among banks, even though branch banking allows banks to differentiate themselves through their choices of branch locations. Banking services at peripheral locations will be priced more competitively when those locales are served by branch networks. We develop a theoretical model in support of this view and offer empirical evidence.

Consolidation and bank branching patterns

Abstract This paper examines the association between consolidation and changes in levels of bank branching as measured by changes in the number of bank branches per capita. Using a specially-constructed data set, we address this issue as well as how this relationship varies with the type of consolidation and initial regulatory, competitive, and market conditions. We find that merges where merging institutions have branch networks which overlap within a ZIP code (within-ZIP merger) are strongly associated with a reduction in offices per capita in that ZIP code. This result is robust across time and holds in both rural and urban areas. The findings also suggest that, contrary to popularly held views, consolidation is not unambiguously negatively associated with changes in the number of banking offices per capita. Neither within-market-but-not-within-ZIP mergers nor out-of-market mergers consistently show such a relationship. We also find that the relationships between within-ZIP and within-market-but-not-within-ZIP mergers and changes in the number of bank offices per capita are more negative in low-income neighborhoods than in other neighborhoods. However, because most states now have unrestricted branching and because savings associations are less prevalent and financially healthier than in the past, these findings may not be indicative of future branching patterns.

Competition and specialization in the hospital industry: an application of Hotelling's location model

Technological advancement is proceeding rapidly in the hospital industry, as hospitals compete for physicians and their patients. The determinants of such quality competition have been studied extensively [18; 24; 29]. Concomitant with this technological arms race has been the emergence of new services and treatment arrangements, along with increased specialization by hospitals [6; 24]. The specialty mix of a hospital affects its ability to meet patient-specific needs. For instance, hospitals that specialize in coronary care can respond more readily to unanticipated treatment complications among cardiac patients than could other hospitals. Patterns of specialization vary substantially across geographic markets. As Luke [19, 241] notes,

Risk Based Capital Requirements for Mortgage Loans

We develop estimates of risk-based capital requirements for single-family mortgage loans held in portfolio by financial intermediaries. Our method relies on simulation of default and loss probability distributions via simulation of changes in economic variables with conditional default probabilities calibrated to recent actual mortgage loan performance data from the 1990s. Based on simulations with varying input parameters, we find that appropriate capital charges for credit risk vary substantially with loan or borrower characteristics and are generally below the current regulatory standard. These factors may help explain the high degree of securitization, or regulatory capital arbitrage, observed for this asset category.

Credit Scoring: Statistical Issues and Evidence from Credit-Bureau Files

Although credit scoring offers benefits to lenders and borrowers, its use raises important statistical issues that may affect the ability of scoring systems to accurately quantify an individuals credit risk. The evidence from a national sample of credit-bureau records suggests that concerns about omitted-variable bias may be justified, as local economic factors show significant correlations with credit scores. Copyright American Real Estate and Urban Economics Association.