Ryan Bubb

Securitization and Moral Hazard: Evidence from Credit Score Cutoff Rules

A growing literature exploits credit score cutoff rules as a natural experiment to estimate the moral hazard effect of securitization on lender screening. However, these cutoff rules can be traced to underwriting guidelines for originators, not for securitizers. Moreover, loan-level data reveal that lenders change their screening at credit score cutoffs in the absence of changes in the probability of securitization. Credit score cutoff rules thus cannot be used to learn about the moral hazard effect of securitization on underwriting. By showing that this evidence has been misinterpreted, our analysis should move beliefs away from the conclusion that securitization led to lax screening.

Optimal Agency Bias and Regulatory Review

AbstractWhy do bureaucratic principals appoint agents who hold different policy views from themselves? We posit an explanation based on the interplay between two types of agency costs: shirking on information production and policy bias. Principals employ biased agents because they shirk less. This creates an incentive for the principal to use review mechanisms that mitigate the resulting bias in the agents’ decisions. The availability of such review mechanisms encourages principals to employ more extreme agents. We apply the theory to explain various features of the administrative state. In contrast to existing accounts, in our model the use by the president of ideological bureaucrats at regulatory agencies and centralized regulatory review are complements. The use of bias to mitigate shirking results in an amplification of the swings of regulatory policy and heightens the role of regulatory policy in partisan politics.

Consumer Biases and Mutual Ownership

We show how ownership of the firm by its customers, as well as nonprofit status, can prevent firms from using contractual terms that take advantage of consumer biases. By eliminating an outside residual claimant with control over the firm, these alternatives to investor ownership reduce the incentive of the firm to offer such terms. However, customers who are unaware of their behavioral biases may fail to recognize this advantage of non-investor-owned firms. We present evidence from the consumer financial services market that supports our theory. Comparing contract terms, we find that mutually owned firms offer lower penalties, such as default interest rates, and higher up-front prices, such as introductory interest rates, than do investor-owned firms. However, consumers most vulnerable to these penalties are no more likely to use mutually owned firms.

Further Investigations into the Origin of Credit Score Cutoff Rules

Keys, Mukherjee, and Vig (2010a) argue that the evidence presented in Bubb and Kaufman (2009) is based on an inappropriate pooling of loans sold to private-label securitizers with loans sold to the government sponsored enterprises (GSEs). In this paper we investigate the issues raised by the authors and conclude that they do not change our basic analytical approach or conclusions. We examine samples that do not pool together loans sold to these two types of purchasers—a sample of loans bought by the GSEs, a sample of loans originated in 2008–2009 after the private-label market collapsed, and a sample of jumbo loans—and find discontinuities in the number and default rate of loans at credit score cutoffs in the absence of corresponding discontinuities in the securitization rate. We also examine a key assumption underlying their estimates—that no loans are both at risk of being sold to the GSEs and at risk of being sold to private-label securitizers—and show that the data are inconsistent with that assumption. We find that 18 percent of conforming loans in our sample at some time switched between GSE and private-label ownership, demonstrating that the GSEs and private-label securitizers competed for the same loans. Additionally, we show that lender screening cutoffs grew steadily over the period 1997–2010 during which the private-label market rose and collapsed.