OPERATIONS RESEARCH
Vol. 63, No. 6, November–December 2015, pp. 1420–1430
ISSN 0030-364X (print) ISSN 1526-5463 (online)
http://dx.doi.org/10.1287/opre.2015.1433
© 2015 INFORMS
Discounted Utility and Present
Value—A Close Relation
Han Bleichrodt
Erasmus School of Economics, Erasmus University Rotterdam, Rotterdam, 3000 DR, the Netherlands, bleichrodt@ese.eur.nl
Umut Keskin
Department of Economics, Istanbul Bilgi University, 34060 Eyup Istanbul, Turkey, umut.keskin@bilgi.edu.tr
Kirsten I. M. Rohde, Vitalie Spinu, Peter Wakker
Erasmus School of Economics, Erasmus University Rotterdam, Rotterdam, 3000 DR, the Netherlands
{rohde@ese.eur.nl, spinuvit@gmail.com, wakker@ese.eur.nl}
We introduce a new type of preference condition for intertemporal choice, which requires present values to be independent
of various other variables. The new conditions are more concise and more transparent than traditional ones. They are
directly related to applications because present values are widely used tools in intertemporal choice. Our conditions give
more general behavioral axiomatizations, which facilitate normative debates and empirical tests of time inconsistencies and
related phenomena. Like other preference conditions, our conditions can be tested qualitatively. Unlike other preference
conditions, our conditions can also be directly tested quantitatively, and we can verify the required independence of
present values from predictors in regressions. We show how similar types of preference conditions, imposing independence
conditions between directly observable quantities, can be developed for decision contexts other than intertemporal choice
and can simplify behavioral axiomatizations there. Our preference conditions are especially efficient if several types of
aggregation are relevant because we can handle them in one stroke. We thus give an efficient axiomatization of a market
pricing system that is (i) arbitrage-free for hedging uncertainties and (ii) time consistent.
Keywords : intertemporal optimization; present value; discounted utility; time inconsistency; arbitrage-free; preference
axiomatization; decision analysis: sequential; utility: multi-attribute; mathematics: functions.
Subject classifications : decision analysis: sequential; utility/preference: multiattribute; mathematics: functions.
Area of review : Decision Analysis.
History : Received February 2015; revision received June 2015; accepted August 2015. Published online in Articles in
Advance November 5, 2015.
1. Introduction
Debates about appropriate models of intertemporal choice,
both for the normative purpose of making optimal decisions
and for the descriptive purpose of fitting decisions, usually
focus on the critical preference conditions that distinguish
these models. The two most discussed conditions are time
consistency, which plays a role in distinguishing constant
and hyperbolic discounting, and intertemporal separability,
which pertains to habit formation, satiation, addiction, and
sequencing effects.
1
Both time consistency and intertempo-
ral separability are assumed in the classical models but they
are usually violated empirically. Their normative status has
also been questioned.
2
To shed new light on the appropriateness of intertem-
poral decision models, we introduce a new kind of prefer-
ence conditions to distinguish them, stated directly in terms
of present values (PVs). PVs are simple and tractable and
have been widely used in intertemporal choice, both when
reflecting the preferences of the financial market
3
and when
reflecting subjective preferences of individuals.
4
They relate
to the indifferences most commonly encountered in every-
day life. We often have to decide on whether to pay up front
for goods consumed later, whether to pay a price now for
a financial product with future financial consequences, or
whether to choose a savings plan that requires the money
to be delivered now. For these reasons, present values are
widely used in experimental measurements of intertemporal
preferences.
People can more easily relate to independence conditions
imposed on present values than to independence preference
conditions. “For your present value of this extra payment
on day 10, the payments on the other days do (not) matter”
is easier to relate to for most people than the usual pref-
erence conditions (see Equation (16) in §7, for instance).
In general, PVs can depend on many variables, such as
the periods of the receipt of future outcomes, the initial
wealth levels at those periods, and the wealth levels at other
periods. Our preference conditions will impose indepen-
dence of PVs from some of those other variables. We show
that many models can be characterized by the appropriate
independencies.
Like all preference conditions, our conditions can be
tested qualitatively. Unlike other preference conditions,
our conditions can also be directly tested quantitatively.
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