Warwick Business School
University of Warwick
Institutional Affiliation: University of Warwick
NBER Working Papers and Publications
|February 2019||How Do Americans Repay Their Debt? The Balance-Matching Heuristic|
with John Gathergood, Neale Mahoney, Jörg Weber: w25557
In Gathergood et al. (forthcoming), we studied credit card repayments using linked data on multiple cards from the United Kingdom. We showed that individuals did not allocate payments to the higher interest rate card, which would minimize the cost of borrowing, but instead made repayments according to a balance-matching heuristic under which the share of repayments on each card is matched to the share of balances on each card. In this paper, we examine whether these results extend to the United States using a large sample of TransUnion credit bureau data. These data do not provide information on interest rates, so we cannot examine the optimality of payments. However, we observe balances and repayments, so we can examine balance-matching behavior. We replicate our analysis and find that Am...
|Naïve *Buying* Diversiﬁcation and Narrow Framing by Individual Investors|
with John Gathergood, David Hirshleifer, David Leake, Hiroaki Sakaguchi: w25567
Individual investors buying multiple stocks on the same day often use a naïve diversification 1/N heuristic, dividing purchase value equally across stocks. Yet very few investors maintain a 1/N portfolio allocation. Instead, investors appear to narrowly frame their buy-day decision independently of their portfolio, applying the 1/N heuristic only for new purchases. The use of this heuristic decreases, but does not disappear, as financial stakes and investor trading experience increase. These findings indicate that the simple heuristics individual investors use in practice depart further from rationality than is often assumed even in behavioral models of investment decisions.
|December 2017||How Do Individuals Repay Their Debt? The Balance-Matching Heuristic|
with John Gathergood, Neale Mahoney, Joerg Weber: w24161
We study how individuals repay their debt using linked data on multiple credit cards. Repayments are not allocated to the higher interest rate card, which would minimize the cost of borrowing. Moreover, the degree of misallocation is invariant to the economic stakes, which is inconsistent with optimization frictions. Instead, we show that repayments are consistent with a balance-matching heuristic under which the share of repayments on each card is matched to the share of balances on each card. Balance matching captures more than half of the predictable variation in repayments and is highly persistent within individuals over time.