Choice over Time

Consumer intertemporal preferences Gal Zauberman1 and Oleg Urminsky2

Available online at www.sciencedirect.com

ScienceDirect

Consumers’ intertemporal preferences have been studied

across multiple theoretical and applied areas. This article

outlines research showing that the context in which

intertemporal preferences are expressed matters, as well as

research exploring the mechanisms that account for these

effects. These processes range from emotion-based to various

cognitive-based accounts, and focus on the outcomes relevant

to the choice, the future self, the perception of resources, and

the perception of the time horizon relevant to the choice. The

various mechanisms surveyed all tend to result in a heightened

motivation for an immediate outcome, compared to a distant

one. Understanding these mechanisms can yield better

designed behavioral interventions that could increase

farsighted consumer decision making and improve consumers’

long-term well-being.

Addresses 1 Yale University, USA 2 University of Chicago, USA

Corresponding authors: Zauberman, Gal ([email protected]) and

Urminsky, Oleg ([email protected])

Current Opinion in Psychology 2016, 10:136–141

This review comes from a themed issue on Consumer behavior

Edited by Jeff Joireman and Kristina M Durante

For a complete overview see the Issue and the Editorial

Available online 22th January 2016

http://dx.doi.org/10.1016/j.copsyc.2016.01.005

2352-250X/Published by Elsevier Ltd.

Intertemporal choices range from the very simple to the

complex, but all hinge on a tradeoff between a sooner

outcome with lower value (e.g. $10 tomorrow) and a later

outcome with higher value ($20 in a year). A wide range of

consumer decisions share this basic temporal structure,

such as whether to have a cookie for dessert or opt for

the healthier but less tasty option; whether to purchase

the more costly and efficient appliance or car that pro-

vides savings in the future; whether to spend money and

time now to refinance a mortgage to a lower future

interest rate, or even whether to impose a carbon tax

now for future environmental benefit.

The literature on intertemporal preferences, across mul-

tiple academic disciplines, including economics, psychol-

ogy, business, and public policy has grown extensively

over the last 25 years. The amount of new research on

Current Opinion in Psychology 2016, 10:136–141

intertemporal choice is due to both the complexity of the

psychological processes and the wide range of potential

applications. Prior reviews have discussed how the time

discounting literature in economics and psychology de-

veloped [1 ��

], models of intertemporal choice [2], and the

psychological foundations of intertemporal decisions and

their behavioral implications [3 ��

].

In this short review article we will therefore only provide

an introduction to this vast literature, focusing on what

motivates consumer patience or impatience. The main

goal of the current article is primarily to introduce the

reader to the psychological foundation of intertemporal

decisions, and will be structured as follows: (a) a brief

discussion of early work, mostly examining empirical

regularities, followed by (b) a discussion key psychologi-

cal processes that underlie these decisions.

The nature of intertemporal preferences In intertemporal decisions, people discount the value of

an option, based on the delay to receive the option. The

amount by which an option’s value declines when it is

delayed is captured by a discount rate. Early research on

the behavioral aspects of intertemporal preferences has

documented numerous ‘anomalies’, or violations of a

normative standard — the discounted utility model [4].

In particular, the normative model assumes that the

discount rate in intertemporal decisions is constant and

does not depend on the source of utility (e.g. whether the

now vs. later decision is about time, money, or food), since

it is the utility that is being discounted. A great deal of

evidence has been amassed showing that these assump-

tions are commonly violated [1 ��

,3 ��

].

The first notable empirical finding is impatience — indi-

viduals tend to forego larger future rewards in order to

receive smaller rewards sooner, a behavior that has often

been referred to as high rate of discounting. Researchers

have also documented a great deal of heterogeneity across

people and situations in their degree of patience. It is

often unclear what constitutes a non-normatively high

rate of discounting, and the prevailing monetary market

rates are often used as a basis of comparison. However,

other normative factors such as risk, low liquidity and

short-term opportunity costs may also contribute to high

discount rates.

Researchers have also documented that intertemporal

preferences are highly context dependent. For example,

the empirical discount rate is higher for short delays than

longer delays, higher for smaller amounts than larger

amounts, higher for gains than for losses [5], higher when

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Consumer intertemporal preferences Zauberman and Urminsky 137

delaying a current amount than when expediting a future

amount [6,7], higher when expressed in terms of delays

rather than dates (e.g. on March 1st vs. in 6 months) [8,9],

and is often different for different resources (e.g. higher

for future time than future money [10 ��

]).

The empirical regularity that has received the most

attention is the sensitivity of discount rates for a given

delay to when that delay will occur. A large literature has

demonstrated higher (annualized) discounting for delays

of immediate outcomes than for the same delay of a future

outcome. That is, while people often require more to

delay for one year than one month, the annualized (or per

day) rate will typically be higher for shorter than longer

periods. For example, Thaler [5] found median discount-

ing over a set of values to be 345% over a one-month

delay, 120% over a one-year delay, and only 19% over a

10-year delay. The implication of this sensitivity of dis-

counting to time horizons is that preferences are time

inconsistent, which would then result in preference rever-

sals [11 � ]. For instance, a person who prefers $1 today over

$2 in a week might nevertheless prefer $2 in a year and

one week over $1 in a year. This tendency for higher

discounting of present delays is often referred to as

‘hyperbolic discounting,’ ‘declining impatience,’ or ‘pres-

ent bias’.

Psychological determinants of intertemporal choice The early work documenting empirical regularities and

violations of normativity provided an important step in

our understanding of how people make intertemporal

tradeoffs, but the psychological factors underlying time

preferences were not of primary interest. More recently,

research has shifted toward a more systematic study of the

psychological determinants of intertemporal preferences.

It is important to note upfront that intertemporal prefer-

ences are complex and no single psychological mecha-

nism could possibly explain all situations. Still,

understanding the psychological underpinnings may re-

sult in a better understanding of intertemporal prefer-

ences and behavioral interventions that would influences

preferences.

Emotional accounts. George Ainslie [11�] noted the cen- tral role of impulsivity in intertemporal decisions. Loe-

wenstein [12] argued that visceral factors, especially drive

states (e.g. hunger), have a significant influence on inter-

temporal decisions, in particular because people often do

not anticipate the influence of these factors on their

decisions. Stimuli that are associated with such factors

and can thus satisfy the particular state of deprivation

(such as water when thirsty, etc.) are most likely to display

impulsive preferences that are difficult to anticipate. In

line with this affect based mechanism, Shiv and Fedor-

ikhin [13] present evidence that the preference for an

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affect-rich chocolate cake (with immediate benefits of

taste) versus a more affect-poor fruit salad (with long-term

benefits of health) increases when cognitive resources are

low (e.g. under cognitive load), reducing people’s ability

to override impulsive tendencies. However, there is also

evidence that the discounting of visceral rewards over

short experienced delays, where impulsivity is likely to

play the largest role, represents a different type of dis-

counting, distinct from prospective discounting of future

monetary rewards [14]. Differences in emotional states

may also directly impact discounting, such as sad people

being more impatient [15].

Goal proximity. Intertemporal choices may also represent a conflict between competing goals. Consistent with this

possibility, Urminsky and Kivetz [16] document a ‘mere

token’ effect, in which providing perceived progress on

the immediacy goal (i.e. adding a small immediate

amount to both the sooner-smaller and later-larger

options) increases the later-goal motivation (choices of

the later-larger option), particularly when choice conflict

is high. More broadly, the preference for immediacy in

time discounting parallels the goal gradient in motivation,

in which nearer outcomes are more motivating [17,18 ��

].

While some goal gradient results could be explained by

discount rates, Urminsky and Goswami [19] indepen-

dently manipulate goal completion and reward timing,

and find evidence that goal gradient effects may contrib-

ute to elicited time discounting.

Connectedness. Intertemporal choices involve a tradeoff between costs and benefits to the present and future self.

Parfit [20] argued that people who see their present and

future selves as the same person should normatively

weight delayed outcomes more highly than if they see

the future self as fundamentally different, almost like

another person. Recent empirical research suggests that

the degree of psychological ‘connectedness’ people have

with their future self (i.e. the perceived stability of their

identity [21]) relates to their motivation to forego imme-

diate consumption and benefit the future self [22 � ,23 ��

].

Neural-activation approximations of connectedness cor-

relate with discount rates [24], and people who have been

made to feel more connected to their future selves exhibit

lower discount rates [23 ��

].

Differences in perceived connectedness over time can

also help explain hyperbolic discounting [22 � ], as both

patience and connectedness to the future self decline

more over time from the present than from a future

starting point.

Mental representation. The way in which options are mentally represented seems to play a key role in inter-

temporal choices. Construal Level Theory [25] argues

that evaluations of the near future are more concrete,

whereas the evaluations of future outcomes are more

Current Opinion in Psychology 2016, 10:136–141

138 Consumer behavior

abstract. The level of representation can then affect

intertemporal preferences, as abstract mental construal

leads to greater ability to compare non-alignable differ-

ences [26], to more self-control [27] and less present-bias

[10 ��

,28]. Malkoc and Zauberman [10 ��

] also demonstrat-

ed that the greater concreteness of outcomes in the near

future, compared to the distant future, contributes to

higher discounting in delay versus expedite decisions.

When considering whether to delay a DVD available

today, the reduction in enjoyment from watching it later

is more vivid than the gain in enjoyment when consider-

ing whether to expedite the receipt of a DVD originally

expected next month [28]. These differences in repre-

sentations are malleable, and mentally simulating future

outcomes moderates the standard temporal construal

effects by changing the weight of the different attributes

[29].

Opportunity costs. In those intertemporal decisions where the tradeoff is implicit (e.g. whether or not to

purchase, which trades-off spending money now vs. sav-

ing for the future), people may also have an incomplete

representation, and fail to appreciate the more remote

future consequences of their choices, contributing to

present bias. Recent research has shown that people often

fail to take into account unspecified opportunity costs of

their decisions [30,31], and both connectedness to the

future self and discount rates better predict consumer

spending choices when opportunity costs are made salient

[32 � ], see Figure 1. Zauberman [33] shows that the failure

to consider future switching costs is also associated with

consumer lock-in. That is, a consumer buys boots at

Zappos.com, without realizing that the next time they

buy a pair it will be easier to go back there, compared to

Figure 1

60%

P ro

b a b ili

ty o

f C

h o o si

n g

E xp

e n si

ve P

ro d u ct

( +

/– S

E M

)

50%

40%

30%

20%

10%

0% Low Connectedness, Tradeoffs Not Cued

High Connectednes Tradeoffs Not Cue

Joint effect of connectedness and opportunity cost salience (rank first = hig

option). People are most likely to prioritize saving over spending when they

choices about less strongly desired products.

Current Opinion in Psychology 2016, 10:136–141

the competition. This future effort is being discounted,

making them subsequently more likely to go back to

Zappos.com than they had initially anticipated.

Resource slack. More broadly, Slack Theory [10��] argues that the perceived level of available resources, or ‘slack’,

influences intertemporal preference. Slack is ‘the per-

ceived surplus of a given resource available to complete a

focal task without causing failure to achieve goals associ-

ated with competing uses of the same resource’ [10 ��

].

For example, Zauberman and Lynch [10 ��

] show that

intertemporal preferences, including overall discount

rates, the extent of hyperbolic discounting, and differ-

ences in discounting between resources (i.e. time and

money) can be explained by differences in perceived

slack over time. They show that because people generally

believe that they will have more slack in the future (e.g. I

expect to be much less busy in 3 months than I am now),

and because the perceived increase in slack is greater for

time than for money (how much more free time I will

have in 3 months shows more growth than how much

more money I expect to have in 3 months), people also

tend to discount time more than money. This theory also

predicts that people will show negative time discounting,

preferring to complete a task or take on an expense now

rather than later, when they expect less slack in the future

than the present.

Time perception. While the cognitive mechanisms men- tioned so far have centered on how people perceive the

value of alternatives, recent work has started to explore

the role of how the time horizon (delay) itself is perceived

and considered. The role of time in intertemporal deci-

sions could be conceptualized in terms of the weight

Low Connectedness, Tradeoffs Cued

s, d

High Connectedness, Tradeoffs Cued

Three More Desirable Products

Three Less Desirable Products

Current Opinion in Psychology

h; choose first = low) on price sensitivity (choosing the more expensive

are connected to the future self, thinking about tradeoffs, and making

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Consumer intertemporal preferences Zauberman and Urminsky 139

Figure 2

350

300

250

200

150

100

50

0 3 6 9 12

Months

D is

c o

u n

t R

a te

( %

)

Objective time Subjective time

15 18 21 24 27 30 33 36

Current Opinion in Psychology

The rate of discounting calculated based on objective and subjective

time. The figure shows classic hyperbolic discounting with respect to

objective time, but a near-constant rate of discounting with respect to

subjective time.

given to the time delay versus the value being delayed

[34,35], as well as the way in which time is actually

subjectively perceived [36 ��

,37,38].

Zauberman et al. [36��] empirically demonstrated that people’s perception of future time durations follows a

standard nonlinear psychophysical function rather than a

linear mapping to calendar time, which can account for

observed hyperbolic discounting (see Figure 2). Further-

more, those individuals who perceived a given future

duration as longer discounted outcomes over that dura-

tion more steeply, compared to those who perceived the

delay as shorter [37].

Factors that change the perceived length of a given delay

also have been found to change the level of discounting

over the same duration. Zauberman et al. [36��] found that asking people to judge expected durations of various tasks

(e.g. learning a new language, or painting a house), makes

people more sensitive to time and more linear in their

perceptions, and they therefore show less hyperbolic

discounting. Kim et al. [37] applied the relationship between spatial distance and temporal distance, where

people judge a given delay to be longer when it is

associated with a longer spatial distance than a shorter

one (e.g. a far-away vs. nearby location). They then

showed that the subjectively longer time judgments

are associated with more discounting. Following a similar

logic, Kim and Zauberman [39] showed that because

individuals perceive a given future time duration to be

longer when they are exposed to sexual cues, they were

more impatient for immediate monetary rewards when

sexually aroused. In sum, these findings establish that the

way people perceive future time itself is an important

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factor in how they form their intertemporal preferences

(for brain imaging evidence, see Cooper et al. [40]).

Conclusions Gaining a better understanding how people form inter-

temporal preferences has been of great interest across

multiple theoretical and applied areas because of its

direct relevance to a wide range of real-world behaviors.

Prior research has found that intertemporal preferences

relate to people’s savings behaviors [41 � ,42], consumer

self-control and purchase decisions [32 � ,43–45], employ-

ment decisions [46], educational investment [47,48], en-

ergy conservation [49], and health behaviors and

outcomes [50–52] (see Urminsky and Zauberman [3 ��

]

for a full integrative review).

This article provided a brief overview of the underlying

psychological mechanisms that drive intertemporal pre-

ferences. The mechanisms outlined range from emotion-

based to cognitive, and relate to the decision context,

mental representations, how people think about their

future self and their goals, the perception of resources

and outcomes, and the perception of the time horizon

relevant to the choice.

While intertemporal preferences are inherently multiply

determined, a great deal of progress has been made in

recent years in understanding the processes involved in

intertemporal decisions. What is common across the

various factors influencing intertemporal preferences is

that all these mechanisms influence the relative attrac-

tiveness of achieving a present goal compared to a later

more distant one.

Further research is needed to better understand how

these different mechanisms interact in shaping intertem-

poral preferences, as well as the mapping between time

preferences and how people make relevant real-world

decisions [53 � ]. While key pieces of the puzzle have been

identified, much work remains to develop a comprehen-

sive theory that will enable us to predict under what

conditions people will be most likely to make farsighted

choices, in their long-term self-interest. This will result in

better-designed behavioral interventions that could

improve consumer decision making and well-being.

Conflict of interest statement Nothing declared.

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� of special interest �� of outstanding interest

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140 Consumer behavior

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