We document substantial cross-individual dispersion in U.S. credit card borrowing costs, even after controlling for borrower risk and card characteristics. That remaining dispersion arises because cross-lender pricing heterogeneity generates dispersion in annual percentage rate (APR) offers to borrowers, and borrowers vary in shopping intensity. Our empirics match administrative data to self-reported card shopping intensity and use instruments suggested by fair lending law to account for the endogeneity between APRs and search. The results show that shoppers versus nonshoppers pay APRs as different as those paid by borrowers in the best versus worst credit score deciles. We discuss implications for policy and practice.

We explore dynamics of limited attention in the $35 billion market for checking overdrafts, using survey content as shocks to the salience of overdraft fees. Conditional on selection into surveys, individuals who face overdraft-related questions are less likely to incur a fee in the survey month. Taking multiple overdraft surveys builds a "stock" of attention that reduces overdrafts for up to two years. The effects are significant among consumers with lower education and financial literacy. Individuals avoid overdrafts by making fewer low-balance debit transactions and cancelling automatic recurring withdrawals. The results raise new questions about consumer financial protection policy.

[We posit that consumer lenders shroud interest rates and market "low monthly payments" to price discriminate on "fuzzy math" or "payment/interest bias": consumers' pervasive tendency to underestimate borrowing costs when an interest rate is not disclosed. We test whether mandated disclosure changes lenders' ability to price discriminate using withinhousehold interactions between payment/interest bias and policy-induced variation in the strength of Truth-in-Lending Act (TILA) enforcement across lenders and time. Weak TILA enforcement substantially widens the gap between rates paid by more-biased and lessbiased borrowers. TILA compliance costs appear to increase interest rates overall, making the net effect on interest rates ambiguous.]

Exponential growth bias is the pervasive tendency to linearize exponential functions when assessing them intuitively. We show that exponential growth bias can explain two stylized facts in household finance: the tendency to underestimate an interest rate given other loan terms, and the tendency to underestimate a future value given other investment terms. Bias matters empirically: More-biased households borrow more, save less, favor shorter maturities, and use and benefit more from financial advice, conditional on a rich set of household characteristics. There is little evidence that our measure of exponential growth bias merely proxies for broader financial sophistication.

Many credit card issuers charge “fixed rates” that remain the same for three to five years, while the rest charge “variable rates” that are indexed to market rates. The presence of these two distinct rate types forces prices at firms selling an otherwise identical product to move asynchronously; variable rates move one-for-one with the index, while fixed rates stay constant. Empirical and theoretical analysis shows that this pricing structure provides an explanation for the simultaneous (yet seemingly contradictory) existence of high rate-cost margins and aggressive non-price competition for new customers, a phenomenon that existed in the credit card market in the early 1990s.

Abstract We examine how 17 behavioural biases relate to each other, to three standard measures of risk and time preferences, to cognitive skills, personality, and demographics, and to outcomes in household finance, well-being, and health. Most consumers in our nationally representative panel data exhibit multiple biases, with substantial cross-person heterogeneity. Biases are positively correlated within person, especially after adjusting for measurement error. From that correlation structure, we reduce our 20 bias and standard preference measures to four behavioural common factors. Each BCF reflects a group of related biases regarding beliefs, decision quality, discounting, or risk/uncertainty attitudes. The first two BCFs also strongly correlate with each other (positively) and cognitive skills (negatively). The first three BCFs and cognitive skills strongly correlate with various outcomes in the expected directions. Our results support processing-based models where basic limitations in cognition and/or attention produce multiple biases, and they have several other implications for theory and practice.

We document substantial cross-individual dispersion in U.S. credit card borrowing costs, even after controlling for borrower risk and card characteristics. That remaining dispersion arises because cross-lender pricing heterogeneity generates dispersion in annual percentage rate (APR) offers to borrowers, and borrowers vary in shopping intensity. Our empirics match administrative data to self-reported card shopping intensity and use instruments suggested by fair lending law to account for the endogeneity between APRs and search. The results show that shoppers versus nonshoppers pay APRs as different as those paid by borrowers in the best versus worst credit score deciles. We discuss implications for policy and practice. Received August 2, 2014; accepted July 7, 2015 by Editor Philip Strahan.

We explore dynamics of limited attention in the $35 billion market for checking overdrafts, using survey content as shocks to the salience of overdraft fees. Conditional on selection into surveys, individuals who face overdraft-related questions are less likely to incur a fee in the survey month. Taking multiple overdraft surveys builds a “stock” of attention that reduces overdrafts for up to two years. The effects are significant among consumers with lower education and financial literacy. Individuals avoid overdrafts by making fewer low-balance debit transactions and cancelling automatic recurring withdrawals. The results raise new questions about consumer financial protection policy.

We posit that consumer lenders shroud interest rates and market “low monthly payments” to price discriminate on “fuzzy math” or “payment/interest bias”: consumers' pervasive tendency to underestimate borrowing costs when an interest rate is not disclosed. We test whether mandated disclosure changes lenders' ability to price discriminate using within-household interactions between payment/interest bias and policy-induced variation in the strength of Truth-in-Lending Act (TILA) enforcement across lenders and time. Weak TILA enforcement substantially widens the gap between rates paid by more-biased and less-biased borrowers. TILA compliance costs appear to increase interest rates overall, making the net effect on interest rates ambiguous.

What Do Consumers Really Pay on Their Checking and Credit Card Accounts? Explicit, Implicit, and Avoidable Costs by Victor Stango and Jonathan Zinman. Published in volume 99, issue 2, pages 424-29 of American Economic Review, May 2009