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Quarterly Journal of Economics Vol. 128 No. 4 2013

Fungibility and Consumer Choice: Evidence from Commodity Price Shocks*

Justine Hastings1; Jesse M. Shapiro2

1 Brown University · 2 Booth University College

open access

Abstract

We formulate a test of the fungibility of money based on parallel shifts in the prices of different quality grades of a commodity. We embed the test in a discrete-choice model of product quality choice and estimate the model using panel microdata on gasoline purchases. We find that when gasoline prices rise consumers substitute to lower octane gasoline, to an extent that cannot be explained by income effects. Across a wide range of specifications, we consistently reject the null hypothesis that households treat "gas money" as fungible with other income. We compare the empirical fit of three psychological models of decision-making. A simple model of category budgeting fits the data well, with models of loss aversion and salience both capturing important features of the time series.

DOI
10.1093/qje/qjt018
Volume
128
Issue
4
Pages
1449-1498
Language
en
Sources
bibtex:phds-export.bib openalex crossref

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