발행일 : 2015년 12월 24일
Factors influencing on users’ continuance intention toward
car sharing service:
An extension of the expectation-confirmation model
Seulgi Lee
Department of Management Engineering, KAIST
Abstract
Car sharing is a service that provides temporary mobility ownership, and its market is
growing in global size. Due to its several environmental merits, car-sharing is considered as a
promising sustainable service. This paper aims to investigate potential factors leading
customers to continuously use car-sharing service. The original model was constructed from
Expectation Confirmation Theorem. The existing model is extended by introducing two
additional factors; Economic Incentives and Environmental Self-identification. Findings from
this study will help car-sharing service to improve user retention rate and grow further in
business size.
໋Supervisor: Professor Jaemin Jung
Copyright by Graduate School of Green Growth, College of Business, KAIST. All Rights Reserved. All Pages
cannot be copied without permission
Table of Contents
1.
INTRODUCTION
2.
BACKGROUND REVIEW
4
CAR-SHARING SERVICE
4
2.1.
2.1.1.
2.2.
3.
3
TYPES OF CAR-SHARING SERVICE
5
EXPECTATION CONFIRMATION MODEL
EXTENDED EXPECTATION CONFIRMATION MODEL
3.1.
EXPECTATION CONFIRMATION MODEL
3.2.
ECONOMIC INCENTIVE
3.3.
ENVIRONMENT SELF-IDENTIFICATION
4.
7
METHODOLOGY
11
14
4.1.
QUESTIONNAIRE DEVELOPMENT
4.2.
DATA COLLECTION AND ANALYSIS 16
REFERENCE
18
10
14
12
10
1. Introduction
In order to hand down a sustainable Earth to future generations, it is universally
agreed upon by researchers that global temperature increase should be kept below 2°C by
controlling greenhouse gas (GHG) concentration in the atmosphere. The objective of this
plan, called the “2°C Scenario”, is to cut energy-related GHG emissions by more than the
half of 2009 in 2050 [26].
It is undeniable that transportation sector is largely responsible for causing
environmental issues. A study revealed that automobile emits major portion of GHG into
the atmosphere; 25 percent of Carbon dioxide, 70 percent of Carbon monoxide, 45 percent
of Nitrogen Oxides and 33 percent of Hydrocarbon is generated from automobile usage
[20]. As a response to growing environmental concern, car-sharing service is rising as a
possible solution. Car-sharing is a service that provides temporary mobility ownership [8].
This service can not only reduce GHGs from inefficient personal automobile use, but also
preserve landscape by preventing over construction of automobile related infrastructures.
As this service is actively offered in North America and Europe, South Korean market also
began to join the global trend.
Car-sharing service in South Korea is growing in fast rate. One head-starting brand in
Korea, SOCAR, was launched in 2011, and already achieved 500 thousands members in four
years. It is notable that the number is more than five-folds of the number a year ago [31].
Currently there are more than two thousands cars actively utilized for the service [31]. For
more convenient user environment, the company announced plans to expand its sphere of
service. The future of car-sharing industry in Korea seems very bright and sustainable.
Car-sharing service is mainly served through mobile application or Internet webpage.
Extensive distribution of smartphone throughout the country accelerated spread of the
service. Meanwhile, for this service to settle completely, the key is about how to attract
KAIST Graduate School of Green Growth Working Paper
loyalty from existing users. In this sense, research objective of this paper is to identify
potential factors that influence consumers’ continuous intention to use car-sharing service.
The theoretical background stems from Expectation Confirmation Theory [3]. ECT enables
us to understand how consumers’ post-purchase continuance intention is determined. In
addition to the original factors from past study, the existing model will be extended by
incorporating economic incentive and environmental self-identification as additional factors.
2. Background Review
2.1.
Car-sharing service
Through revolutionary mass production development, car has become a common
personal property in the twenty-first century. Especially in South Korea, the nation that
went through unprecedented innovation over last decades, number of cars increased
tremendously. Consequently, construction of additional parking and driving infrastructure
was inevitable. However, an argument sparked on questioning whether those cars are being
fully utilized. For instance, numbers of automobiles are easily found idling in parking lots.
One research discovered average car is being driven for only one hour or less during a day
[24]. Moreover, convenience provided from personal automobile leads car owners to give
little consideration before driving. Most of the time people decide to drive even for short
distance trips. Due to this inefficient car using habit, valuable raw materials are used in vain.
As people become more conscious about environment issues, such ignorant behavior was
pointed first to fix.
Traditionally, the only way of driving a car was either by purchasing or through rental
service. However, increasing economic cost from insurance, maintenance and fluctuating
fuel cost made it burdensome to possess a personal car [14]. Consequently, more people
began to cry out for affordable alternatives.
KAIST Graduate School of Green Growth Working Paper
As the concept of sharing economy opened up a new pathway to sustainability, the
idea of car ownership has transformed. Sharing economy, or also known as collaborative
consumption, is obtaining, giving or sharing peer-to-peer activity via community based
online service [16]. According to Botsman and Rogers, there are three conceptual
requirements for a system to be accepted as sharing economy: Product service,
Redistribution markets and Collaborative lifestyle [7]. Car-sharing service, in all aspects,
satisfies requirements for sharing-economy, and frequently mentioned as a very promising
sustainable mobility service.
So far car-sharing lacks related academic study and official technical definition. Carsharing Association (CSA) specifies it as a service designed for local drivers in support of
short time transit and environmental goals [8]. Its aim is less about financial achievement
but mostly represented by environmental and social vision [8]. As business size expands, it
will settle down as representative ancestor of sustainable business.
2.1.1.
Types of Car-sharing service
Car-sharing service may take several different forms. The form of service depends on
whose car is provided to whom and ultimate vision of service providers.
The history of car-sharing starts in the form of B2C, Business to Consumer. B2C carsharing companies own cars and provide access to their members. What is known as car
rental service is a traditional form of B2C car-sharing. To rent a car from a rental brands,
customers need to visit a desired rental company’s office and rent for promised period of
time. The process requires steps of agreement paper work. The charging fee is in daily unit,
and customers should return the car to the same company’s office. Automobile
manufacturing companies such as BMW, Peugeot and Daimler also share their cars to
members in a similar way. For a long time, this form of the service was served for short
period use.
KAIST Graduate School of Green Growth Working Paper
In contrast to traditional B2C service, the latest form of B2C car-sharing is provided by
car-sharing companies. Although it is very similar to traditional rental service, there are
some differences that make B2C unique and modern. The most desirable characteristic is
smaller charging unit. Customers are free to choose their convenient time in minute-base.
Plans and rates may differ across companies but they are reasonable considering inclusion
of gas and insurance fee. For instance, Zipcar provides different plans for individual,
business and student customers. On the other hand, Korean companies charge in time
basis only. The minimum rental time is 30 minutes and it can be elongated by in the unit
of 10 minutes. Shorter rental time unit lets drivers to drive and pay efficiently, which
consequently lead to voluntary energy saving. Convenience is another merit to be praised.
Dispersed stations throughout service area provide more flexible access to customers. Since
the service is provided via web and mobile phone application, development of high speed
Internet, mobile broadband and GPS system facilitate advanced service quality. Customers
can easily find the nearest station and check available car models during suitable period.
Needless to go through compulsory paper works, customers can simply sign in and make
an appointment instantly. B2C car-sharing business is still a developing sector, and
providers are eager to promote the service quality.
Although relatively rare, Not-for-Profit car-sharing companies also exist. The service
format is exactly the same as B2C. However, the NFP car-sharing companies put aside
financial ambition and focus more on social and environmental missions. Currently, City Car
Share, Philly Car Share and I-GO Chicago are well known NFP car-sharing brands.
Companies do not necessarily have to own cars to provide car-sharing service. Peer-toPeer car-sharing serves a market for individuals who are willing to share personal vehicle
with their neighbors. The service match car seekers with available car owners. This service
gives monetary motive to car owners and minimizes waste of personal automobiles by
utilizing cars as much as possible. RelayRides, Whipcar, Wheelz and Getaround are
KAIST Graduate School of Green Growth Working Paper
companies with P2P car-sharing market. However, due to cultural and self-boundary issue,
some consumers are less willing to put their properties out to the public market.
Regardless of its form, car-sharing is growing globally with notable record. In 2009, car
sharing successfully reduced Carbon dioxide emission by 482,170 tons [29]. With 10,405
cars being shared in North America with 516,100 users, the impact of one rented car was
revealed to substitute 15 cars on the road [29]. Such remarkable numbers confirmed that
car-sharing service has bright future for sure.
[Table 1] Types of Car-sharing service
Type
Characteristics
Examples
Auto Maunfacturers:
BMW, Peugeot, Daimler
Business to
Car-sharing companies own cars and
Rental Brands: Hertz,
Customer (B2C)
provide access to their members.
WeCar
Car-sharing Brands:
Zipcar, StattAuto, GoGet
Similar to B2C, companies provide
automobile to their members.
Not-For-Profit
Focuses on social and environmental
City Car Share, Philly Car
Share, I-GO Chicago
missions, rather than
Individual puts own vehicle to share in
Peer to Peer (P2P)
the market, and service members are
allowed to use cars out in the market.
RelayRides, Whipcar,
Wheelz, Getaround
Source: The Bright Future of Car-sharing [29]
2.2. Expectation Confirmation Model
Theoretical background of Expectation Confirmation Model (ECM) is Expectation
Confirmation Theory (ECT). ECT was established to study the mechanism of consumers’
repurchase behavior. While pre-purchase consumer behavior was majorly discussed in the
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past, this theory was novel in a way by approaching influence of post-purchase satisfaction
on continuous use intention.
[Figure 1] Expectation Confirmation Theorem
The process of repurchase decision making described by ECT is illustrated in Figure 1.
Specific process is as follows [23]. Before purchasing certain product, consumers build up
pre-purchase expectation of the product. This initial expectation leads them to purchase
and experience the product for the first time. Through initial experience, consumers
evaluate its performance and attain perceptions about it. After consumers’ cognitive
assessments about the product are made, either confirmation or disconfirmation is formed.
If perceived performance concords well with pre-purchase expectation, confirmation ensues.
However, occurrence of discrepancies between the two cognitive variables results
disconfirmation. There are two types of disconfirmation: positive and negative. If products
outperform or meet the ex-ante expectation, consumers are positively disconfirmed. In the
opposite case, consumers are negatively disconfirmed [10]. The final level of confirmation
affects satisfaction, which leads customers repurchase or continue to use the product.
As an extension to the theory, Bhattacherjee suggested that ECT could also be applied
to investigate one’s continued Information System usage decisions. In fact, most part of
contemporary service is similar to traditional tangible products. Before adoption decision is
made, IS users have certain expectation about the service before their initial experience. The
KAIST Graduate School of Green Growth Working Paper
ex-ante expectation is a stimulus, which makes consumers to end up with adoption decision.
The perceived quality of the service experience is highly influenced by the prior expectation.
Thus, either confirmation or disconfirmation leads continuous or discontinuous use of IS. The
scenario seems to perfectly fit for ECT. However, in order to extend the idea to a different
context, Bhattacherjee made additional improvement on the theory and established a new
model, Expectation Confirmation Model (ECM).
[Figure 2] Expectation Confirmation Model
There are key conversions made in ECM, which differentiate the model from the
construction of ECT. Entire model is illustrated in Figure 2. One modification comes from
different perceived time of cognitive variables. ECT primarily looked into both pre and post
acceptance level of perceptions. ECM, on the other hand, selected to examine postacceptance variables only. This does not mean pre-acceptance level of expectation was
neglected in ECT. Instead, the effect of pre-acceptance variables was captured in
confirmation and satisfaction.
Additional amendment was made on some old constructs. The new model included postacceptance expectation into the model, which was not considered in the original theory.
Expectation is time changing cognitive variable, and especially in IS usage context, this
perception is more vulnerable to change. Therefore expectation after purchase is more
appropriate to incorporate. This concept was named as perceived usefulness in the new
KAIST Graduate School of Green Growth Working Paper
model. Although post-purchase expectation seems more encompassing, definition of
perceived usefulness justifies the revision. Technology Acceptance Model (TAM) defines
perceived usefulness as “the degree to which a person believes that using a particular system
would enhance his or her job performance” [13]. With suitable extension and alternation, ECM
is accepted widely as a good mechanism for investigation of factors influencing on IS
continuous use.
3. Extended Expectation Confirmation Model
3.1.
Expectation Confirmation Model
With theoretical support from ECT, similar hypotheses can be justified in the context of
car-sharing service. From the initial car-sharing service experience, customers form
confirmation according to their perceived cognition state. ECT suggests the confirmation has
positive influence on perceived usefulness. The resulted perceive usefulness and confirmation
both act upon satisfaction as positive antecedents. Finally, satisfaction has positive impact on
continuance intention to use car-sharing service. The list below summarizes suggested
hypotheses.
H1: Confirmation from car-sharing experience has positive influence on Perceived Usefulness.
H2: Confirmation from car-sharing experience has positive influence on Satisfaction level of
users.
H3: Perceived Usefulness of car-sharing service has positive influence on Satisfaction level of
users.
H4: Perceived Usefulness of car-sharing service has positive impact on continuance intention
to use car-sharing service.
H5: Satisfaction level of users has positive impact on continuance intention to use car-sharing
service.
KAIST Graduate School of Green Growth Working Paper
3.2.
Economic Incentive
Living the most capital-centered era, we cannot deny the fact that economic incentive is
irresistible attraction to contemporaries. Perhaps, price is the first coming factor people take
account of in the process of purchase decision making. Yet, in order to maximize one’s utility,
rational consumers refer to the perceived value over labeled price and figure out consequent
economic outcome from purchase commitment. Although sharing economy is often
understood as ecological practice, it is also regarded as economically sound act [16].
Therefore, decision by participants of sharing economy is made for the sake of their own
utility maximization. In fact, economic incentive, such as potential rewards, is a strong
extrinsic motivation to rational consumers [17]. Furthermore, such extrinsic motivation has
significant positive influences on intentions to participate in sharing economy [16].
Beyond the adoption process, economic incentive has overreaching influence even after
the adoption. Bolton and Lemon named post-purchase perceived economic incentive by
payment equity. Payment equity represents the shift in evaluation of the economic fairness
level earned from user experience in relation to paid cost. Their study revealed that
expectation is supportive antecedent of price equity and, simultaneously, it has positive
influence on overall satisfaction of customers [5]. Therefore, it is reasonable to extend the
idea to car sharing context and hypothesize confirmation, which involves expectation, has
positive influence on economic incentive. With the same logic applied, the economic
incentive is a fair antecedent of customer’s satisfaction.
H6: Confirmation from car-sharing experience has positive influence on Perceived Economic
Incentive.
H7: Perceived Economic Incentive from car-sharing experience has positive influence on
Satisfaction level of users.
H8: Perceived Economic Incentive from car-sharing experience has positive impact on
continuance intention to use car-sharing service.
KAIST Graduate School of Green Growth Working Paper
3.3. Environment Self-identification
Every individual bears certain image about oneself in mind. The concept of such selfillustration is referred to as self-identity [11]. Multiple past studies have revealed strong causal
relationship between self-identity and behavioral intention. Especially, self-identity is a strong
motivator on consumption and adoption decision [11].
Environmental self-identity is the degree of how one illustrates oneself to behave
environmental friendly [33]. The idea can be implied to car-sharing. In all aspects, car-sharing
is pro-environmental service. Thus, environmental self-identification becomes a major driver
to initiate and continue service use. After the experience, users generate positive or negative
service impression. Motivation to participate in sustainable behavior in the future is intensified
or weakened respectively [21]. Finally, individual environmental self-identification is adjusted
after the post-environmental experience. A study from Sparks and Shepherd verified
performance of certain behavior affirm related self-identity. [25] Similarly, confirmation from
car-sharing service experience may have positive influence on environmental self-identification.
Moreover, the act of sustainable behavior carried out by environmental self-identity has
positive psychological consequences such as satisfaction, strengths, and mental well-being
[32]. Therefore, users with strong environmental identity will have greater satisfaction from
service experience. Furthermore, Charng et al. discussed the impact of repetitive behavior on
related self-identity. Regardless of one’s old attitude toward the behavior, repetition may
bolster associated self-identity [9]. In a similar vein, it is reasonable to claim that
environmental self-identity effectively persuades individual to frequently use car-sharing
service. From legitimate assumptions, suggested hypotheses are as follows.
H9: Confirmation from car-sharing experience has positive influence on Environmental selfidentification.
H10: Environmental self-identification has positive influence on Satisfaction level of car-
KAIST Graduate School of Green Growth Working Paper
sharing service users.
H11: Environmental self-identification has positive impact on continuance intention to use carsharing service.
[Figure 3] Research Model
[Table 2] Operationalization of Constructs
Construct
Operational definition
User’s perception of the congruence between
Confirmation
expectation of car-sharing service use and its
actual performance
Source
Bhattacherjee
2001 [3]
Perceived
User’s perception of the expected benefits of car-
Davis et al. 1989
Usefulness
sharing service use
[12]
Economic
User’s extrinsic rewards from car-sharing service
Hamari et al.
Incentive
use
2015 [16]
Environmental
The degree of how one illustrates oneself to
Whitmarsh et al.
Self-identification
behave environmental friendly
2010 [33]
KAIST Graduate School of Green Growth Working Paper
Satisfaction
IS Continuance
Intention
User’s affect with feelings about prior car-sharing
service use
Spreng and
Olshavsky 1993
[27]
User’s intention to continue using car-sharing
Bhattacherjee
service
2001 [3]
4. Methodology
4.1.
Questionnaire Development
In this study, there are six constructs to be measured; confirmation, perceived
usefulness, economic incentive, environmental self-identification, satisfaction, and IS
continuance intention. Table 2 summarizes operational definition and academic origin of
each construct. Original constructs from ECT will be measured by paraphrasing existing
measures to fit car-sharing context. For new constructs, appropriate measurement will be
brought to evaluate each construct. Economic incentives will be assessed by importing
questions established by Bock et al. [4].
For the measurement of Environmental Self-
identification, Spark and Shepherd’s measurement method will be utilized [25]. All
questions will be measured in a base of 7-point Likert scale, 1 as strong disagreement and
7 as strong agreement. Before actual survey is conducted, validity and reliability tests will
be hold to evaluate construct measurement. Some questions will be eliminated or clarified
for accuracy improvement. Specific list of measurement method follows in Table 3.
[Table 3] Construct Measurements
Construct
Confirmation
Questions
Source
 My experience with using car-sharing service was
Bhattacherjee
better than what I expected.
2001 [3]
KAIST Graduate School of Green Growth Working Paper
 The service level provided by car-sharing service
was better than what I expected.
 Overall, most of my expectations from using the
car-sharing service were confirmed.
 Using car-sharing service improves performance
of my mobility.
Perceived
Usefulness
 Using car-sharing service improves skill of my
portability.
Davis et al. 1989
[12]
 Using car-sharing service enables me to access
wide ranges of location to travel.
 I can save money if I participate in car-sharing.
 My participation in car-sharing benefits me
Economic
Incentive
financially.
 My participation in car-sharing can improve my
Bock et al. 2005
[4]
economic situation.
 My participation in car-sharing saves me time.
 I think of myself as an environmentally-friendly
consumer.
 I think of myself as someone who is very
Environmental
Selfidentification
concerned with environmental issues.
Cook et al. 2002
[11]; Sparks and
 I would be embarrassed to be seen as having an
environmentally-friendly lifestyle (reversed score).
Shepherd 1992
[25]
 I would not want my family or friends to think of
me as someone who is concerned about
environmental issues.
 Using car-sharing service makes me feel very
Satisfaction
satisfied.
 Using car-sharing service makes me feel very
Spreng and
Olshavsky 1993
[27]
KAIST Graduate School of Green Growth Working Paper
pleased.
 Using car-sharing service makes me feel very
contented.
 Using car-sharing service makes me feel very
delighted.
 I intend to continue using the car-sharing service
rather than discontinue its use.
IS Continuance
Bhattacherjee
 My intentions are to continue using the car-
Intention
2001 [3]
sharing service rather than use any alternative
means.
4.2.
Data Collection and Analysis
Data for analysis will be collected through online survey. Subjects of the survey are
members of Korean car-sharing brand. They are required to have experience with car-sharing
service. Filtering out unfinished or inappropriate answers, only valid survey will be accounted
in the final data analysis.
The suggested model will be tested through LISREL 9.2. A Confirmatory Factor Analysis
(CFA) will be conducted as the first step of structural equation modeling. CFA refers to several
representative variables to figure out model fit of the suggested model. Different variables
can be included in analysis such as standardized root mean square residual (SRMSR),
goodness-of-fit (GFI), and comparative fit index (CFI) [2]. The result of CFA explains how
reliable each construct was measured and how much improvement was made compare to the
original model, ECM.
As the following procedure, the structural model assessment will be conducted. Using
the output from the first step, significant test will be held for each suggested hypothesis.
KAIST Graduate School of Green Growth Working Paper
Hypothesis with p-value less than 0.05 will be accepted as significant relation, while one with
p-value greater than 0.05 will be unqualified to be accepted.
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