Running Head: MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
The Mediating Role of Intrinsic Motivations in Personality Traits and Contribution of Consumer
Product Reviews Relationship
Youngsun Kwak
State University of New York at Buffalo
The Role of Social Feedback in Online Product Reviews
: Motivating Contributors
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
2
Abstract
This study are based on an online survey with individuals (n=60), consumer product
reviewers at Amazon.com as well as the content analysis of profile pages of the survey
respondents. The respondents were asked to answer their personality traits and intrinsic
motivations with the scales built in the Self-Determination Theory. Then, their profile pages
were analyzed to get the information of both their contribution level of product reviews and the
amount of social feedback they received from fellow customers. To shed light on the individual
behavior of voluntary participation in product reviews, this study focused on personality traits,
intrinsic and extrinsic motivations, and their relationship. The major findings were two points: (1)
the product reviewers at Amazon.com tended to be under influence of external feedback and
controlled personality; (2) intrinsic motivations mediated the effect of autonomous personality
orientation on contribution of consumer product reviews.
Keywords: Individual Behavior Online, Consumer Product Review, Intrinsic Motivations,
Extrinsic Motivation, Personality Traits, Self-Determination Theory
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
3
Introduction
This study is interested in the role played by social feedback in the context of online
product reviews. Research of online product reviews is skewed into the side of consumers by
whom the online product reviews is perceived as product information. Understanding
contributors on the other hand, especially what drives them to participate in online product
reviews voluntarily and how to read out possible clues in the activities of contributors can bring
balance and fullness to the field of research. Also, it can raise a theoretical question for
academics how to study individual’s behavior in Internet use, in which individual’s role differs
from the one in traditional media use, that is when it switches from the passive role of consumers
to the active one of producers.
Research of online product reviews has been actively conducted in academic fields since
2008. It was prompted by articles drawn from journals in SSCI. During the last 3 years, many
studies have dealt with the relationship between online product reviews and the impact on
individuals who are viewers as well as impact on business sectors. The empirical studies of
online product reviews found that individuals tend to refer to online product reviews when
making a decision of purchasing a product, and it leads, subsequently, to the increase of sales of
a product (Chevalier & Mayzlin, 2006; Forman, Ghose, & Wiesenfeld, 2008; Zhu & Zhang,
2010).
Little research, however, has been done about who contributes to online product review
and what motivates them. A recent survey of online product reviews use among American
Internet users by Pew Internet Research (2010) reported that online product reviews function as
public information pool of products. Consumers research online product reviews before they go
shopping to get information about products; they consider online product reviews as extremely
valuable information source about a product, and have a better overall shopping experience when
they research products online before shopping in-store. In the context of a massive and assertive
advertisements of the products and services addressed to the consumer by the manufacturers and
corporations, the online products reviews can be seen as a precious “third party,” the
involvement of which in a product characterization functions as an objective assessment of a
product, which thus increases trustworthiness of all the talks about the product. That calls for
additional attention to contributors offering online product reviews.
It is a well-known fact that the creation of user generated contents follows the 80/20
Pareto rule, which means 80% of user generated contents are created by 20% of active users.
Online product reviews, however, turned out not to follow the Pareto rule strictly. Pew Internet
Research (2010) reported that about 25% of American Internet users have posted product
comments on products on the web. This is a huge amount of participants compared to other type
of user contribution/participation behavior such as using online discussion boards or posting
video files on Youtube. This statistical finding tells that online product reviews might have
different characteristics from other types of user participation behaviors. A systematic empirical
study is called upon to examine what causes customers’ continuous voluntary participation in
publicly speaking out their shopping experience.
Literature Review
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
4
Writing something on the web has its burdens for individuals who are accustomed to
media consumption not production. Moreover, sustaining the contribution needs an enormous
time investment and overcoming many pressures. Many studies attempted to examine why
individuals voluntarily contribute to online product reviews, and most studies focused on
intrinsic motivations as a driving force for an individual to participate in the behavior. When it
comes to ongoing participation of individuals, however, intrinsic motivations seem to need
additional enhancement to keep the contributors active.
Intrinsic motivation in social computing applications use
Motivation as a psychological construct is to explain individual behavior in terms of
initiating, directing, and preserving a particular behavior to achieve a goal in a certain
circumstance. Motivation is normally classified into two types which are intrinsic one and
extrinsic one. Intrinsic motivation is a conceptual construct applicable to the situations when an
individual is driven to act for the sake of enjoyment, pleasure, cognitive curiosity, or by a sheer
challenge presented to him by the task (Deci & Ryan, 1985a; Ryan & Deci, 2000). It is a natural
propensity of a human behavior to be active, curious, or playful in learning and exploration
without external rewards. Intrinsic motivation theories were claimed to refer to non drive based
motivation in explanation of normal developmental human behaviors (Deci & Ryan, 1985a;
Ryan & Deci, 2000).
Many studies have attempted to shed a light on voluntary participation of individuals in
online social computing applications. They tended to focus on intrinsic motivations of an
individual to understand the individual behavior. For instance, some empirical studies based on
the theory of use and gratification revealed that some intrinsic motivations such as to be fun or to
feel a sense of belongings involves individual participation in online social computing tools
(Lampe, 2005). Likewise, in the context of online product review empirical studies found that
individuals are motivated to contribute to write online product review with self-oriented interests
as well as other-oriented interests. In the analysis of product reviewers at Amazon, Peddibhotla
& Subramani (2007) found that self-oriented motivations of contributors is positively associated
to the amount of contribution , and other-oriented motivations of contributors are positively
associated to the quality fo reviews. The authors defined self-oriented motivations as selfexpression and getting utilitarian benefits; other-oriented motivations as reciprocity and alturism.
Forman (2008) also found that the high level of contribution is positively related to a fun motive
(ego-oriented) whereas it is not related with other oriented factors in the context of online
product reviews.
Intrinsic motivation approach, however, has some limitation when it comes to individual
media engagement not only media consumption for a longer period of time. Thus, it is
questionable that intrinsic motivations are still main motivations when contributors’ site
participation is extended. In recent, circumstance noteworthy occurs in online product review
sites. Online transaction platforms are allowing viewers (fellow customers) to rate both product
reviews and reviewers. In particular, Yelp, known for local small businesses review like
restaurants, provides various kinds of peer feedback routes. Viewers are able to choose one of
feedback items to a product review – useful, funny, and cool. Also, viewers can send
encouraging feedback to reviewers through clicking one of feedback items out of complimentary,
thank you, you’re cool, just a note, you’re funny, and hot stuff. Other sites for online product
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
5
reviews also tend to equip with extensive devices allowing viewers to rate product reviews. This
extensive ways for feedback to contributors might be led by a certain reason, for example, for the
purpose of encouraging contributors to engage ongoing participation. It might be probable to
assume that intrinsic motivations such as self-motivated or other-oriented ones of individuals can
be lasting with intervention of external stimuli such as extrinsic motivations.
Self determination theory
Self determination theory (Deci & Ryan, 1985a), unlikely other intrinsic motivation
approaches, is concerned with the interplay between the intrinsic motivations inherent in human
nature and the external ones from social contexts/environments in leading individuals to initiate
and maintain a certain behavior. The theory defines itself as a broad theoretical framework for
the study of human nature and personality. The concept of self-determination, indicating self
directional and self regulated internal force in human behavior, differs from a drive theory or
intrinsic theories in recognition with individual’s autonomous/willingly/intentional involvement
in his or her behavior. Deci and Ryan (1985) specified three psychological needs to contribute to
satisfy individual’s innate growth tendencies in building self determination theory, which are
competence, relatedness, and autonomy. They provide definitions of the three needs; competence
indicates a sense of effectance in expressing and experiencing individual capacity to make
desirable outcomes; relatedness indicates a sense of connectedness to others to care or to be
cared or a sense of belongings to communities; and autonomy indicates a sense of being
initiative in doing a certain behavior and thus expressing the self. Self determination theory is
composed of several sub theories depending on which need among the three needs is focused.
Self determination as a personality trait
Causality orientations theory (Deci & Ryan, 1985b), one of the five mini-theories of self
determination theory, defined individual differences in perceived locus of causality of behavior
initiation and regulation with three orientations: internal (autonomy) orientation, external
(control) orientation, and impersonal (orientation). The autonomy orientation refers to a high
degree of experienced choice of one’s own behavior. Individuals with a high level of autonomy
are more likely to be internally motivated and less controlled by external rewards. The control
orientation refers to individual behavior strongly under influence of external factors such as
rewards, gains, or approval. The impersonal orientation indicates that individuals believe they
are unable to control their own behavior; for instance, a sense of depression and strong anxiety
can drive individuals into an unintentional direction in their own behavior. Deci and Ryan
(1985b) pointed out that ‘locus of causality’ differs from ‘locus of control’ by Rotter. They
delineated that locus of causality indicates perceived source of initiation and regulation of
behavior whereas locus of control indicates individual’s belief of their behavior either guided by
external factors or internal ones.
External factors facilitating intrinsic motivations
Deci and Ryan (1985) specified external factors to facilitate intrinsic motivations with
cognitive evaluation theory, which is a sub theory of self-determination theory. The theory
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
6
claims external factors such as rewards, communication with others, or positive feedback from
others can enhance individual’s internal motivation of feeling of competence. The feeling of
competence is assumed as a critical motivational factor to cause internal motivation of an
individual in action. In other words, competence means a personal ability to achieve desirable
outcomes. Cognitive evaluation theory explains how external rewards/feedback can contribute to
strengthen intrinsic motivations through the connection to their self-determination theory; that is,
enhanced feeling of competence will stimulate a sense of autonomy, which is an attributional
intrinsic motivation factor, and the increased autonomy leads an individual to the state of
maintenance of the behavior. Cognitive evaluation theory received a strong empirical support
from the field of education. For instance, in classroom learning environment, students who got
positive performance feedback from a teacher showed enhanced intrinsic motivation (Ryan &
Grolnick, 1986).
In a similar vein, Research of individual online behavior related to social computing
applications found evidences supporting the theory. Several empirical studies examined what
motivates individuals to keep posting on social computing tools, and their common finding are
that social/peer feedback is playing a critical role in encouraging or discouraging continued
contributions. (Burke, 2009) examined positive feedbacks (e.g., comments on photos) from
fellow members as predicting ongoing contribution for newcomers who were more active
initially on Facebook use. In the context of online community (Slashdot),(Cliff Lampe, 2005)
found the high rates of drop out of newcomers is caused by negative feedbacks from other
contributors. The rating system of Slashdot allows a negative rating for each post. On the
contrary, (Elisabeth Joyce1, 2006) found the quality of feedback did not affect the likelihood of
newcomer’s posting again in the study of newsgroup. Taken these empirical evidences together,
social feedback from fellow members is one of strong motivations to encourage or discourage
members’ contributions across social media.
Intrinsic Motivations
Personality Traits
Autonomy
Interest/Enjoymen
t
Orientation
-
Controlled
Contribution Level of
Consumer Product Reviews
Orientation
-
Impersonal
Orientation
Extrinsic Motivations
- Positive Social Feedback
Figure 1. A Research Model
Hypotheses
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
7
This study aims to examine the main patterns involved in individuals’ voluntary
participation in consumer product reviews; and also which factors prompt the participants’’
behavior and make them preserver in it. Based on the theory of Self-Determination by Deci and
Ryan, this study suggests two main behavior routes/patterns leading to participation in online
product reviews of individuals. The first of them is grounded in intrinsic motivations.
H1: Intrinsic motivations will be positively influence contribution level of consumer product
reviewers.
Intrinsic motivations may be not enough. The participants may require other stimuli.
Thus, the following hypotheses, concerned with external motivations in the individual voluntary
behavior, can be stated:
H2: Extrinsic motivations will positively influence contribution level of consumer product
reviewers.
The Self Determination Theory assumes that some personality traits enhance intrinsic
motivations or extrinsic motivation, thereby contributing to participants’ voluntary behavior in a
positive way. Therefore, this study formulates the following hypotheses:
H3: Personality traits will positively influence contribution level of consumer product reviewers.
H4-1: Autonomous orientation as a personality trait will be positively related to intrinsic
motivations (interest/enjoyment and perceived choice) and the intrinsic motivations will be
positively related to contribution level of consumer product reviewers (the mediating effect of
intrinsic motivations on contribution level of consumer product reviewers).
H4-2: Controlled orientation as a personality trait will be positively related to an extrinsic
motivation (positive social feedback) and the extrinsic motivation will be positively related to
contribution level of consumer product reviewers (the mediating effect of extrinsic motivations
on contribution level of consumer product reviewers).
Methods
This study employed both a web survey method and a content analysis method. A survey
questionnaire is designed to measure both personality traits and intrinsic motivations of
contributors (voluntary product reviewers). A content analysis method was employed to measure
the level of contribution of the reviewers. Amazon.com provides a profile page for registered
customers at the site. The profile page is for mainly documenting user activities such as product
reviews they purchased at Amazon, photos of the products or wish lists. Amazon.com allows the
public to access to the profile pages. Although a profile page has control functions to protect
information privacy, some menu items consisting of the profile page are given as public. The
default menus include contribution related customer activities such as reviews, lists, guides, and
images of products the customer purchased or is interested in.
Participants
This study contact consumer product reviewers at Amazon through customer community.
Amazon.com provides tons of community forums for customer product reviews and discussions.
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
8
Due to the big volumes of customer discussions of products, Amazon.com does offer tag clouds
or lists of popular forums as indices of customer forums instead of presenting the entire existing
forums. One can access to not listed forums through search function with product related
keywords, for instance, ‘cooking community.’ This study posted a survey participation solitaire
on several popular customer forums, which are kindle, history, rock, Christianity, romance, top
reviewers, and politics. The survey offered a $5 gift card reward for the survey participants to
increase survey response rate and obtained 300 responses.
After collecting survey responses, data filtering process was conducted. It was important
for this study whether or not the survey respondents provide their own authentic profile page at
Amazon.com. The survey included the question to share respondent’s profile name with the
researcher in case of determining the real profile page at Amazon. Then, when sending a follow
up email to send a reward for the respondents, the researcher asked them to provide the
information to verify their participation in the survey in the reply email to the researcher, which
is (1) where they found the survey recruitment announcement and (2) the URL of their profile
page at Amazon.com. This study chose the data if two information related to the profile name are
identical each other: that is, a profile name that a respondent offered in the survey response and
the one in the profile page that a respondent provided the researcher to receive a survey reward.
The final authentic data ended up being 85, which takes 30% of the initial responses.
Measures
Intrinsic Motivation
To measure intrinsic motivations, this study employed the scale of the intrinsic
motivation inventory (IMI) by the self-determination theory (Deci and Ryan, 1984; Deci et al.,
1991). The IMI scale is a multidimensional measure composed of four subscales:
interest/enjoyment, perceived choice, competence, and pressure/tension. There are several
versions of this scale fitting into research interest. Among them, this study utilized a 22-item
version that has been used in several studies: interest/enjoyment (7 items), perceived competence
(5 items), perceived choice (5 items), and pressure/tension (5 items). The items were measured
by a 7-point Likert scales anchored by from not at all true to very true. The scales were assessed
by a factor analysis with the current survey data and adjusted for this study.
General Causality Orientations
This study employed the general causality orientations scales by Deci and Ryan (1985) to
measure individual personality traits. This scale assesses the strength of three different
motivational orientations within an individual. These orientations, labeled autonomy, controlled,
and impersonal, are understood as relatively enduring aspects of personality. There are two
versions of the scale. This study adopted 12 vignettes composed of 36 items validated in a
variety of areas. Each vignette describes a typical social or achievement oriented situation (e.g.,
applying for a job or interacting with a friend) and is followed by three types of responses-autonomous, controlled, and impersonal. Each construct is measured using a 7-pointLikert scale
anchored by from very unlikely to very likely. The scales were assessed by a factor analysis with
the current survey data and adjusted for this study.
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
9
Contribution of Reviewers
Amazon.com profile page is documenting customer activities automatically if they write
product reviews. The profile page is composed of several sub categories such as person related
information (name, location, birthday, anniversary, email, web page, and interests), contributions
(reviews, lists, guides, and images), wish lists and registries, favorite items, and shared recent
purchases. The contribution category is set to open to the public by default. The reviewers can
store their opinion about a product, their know-how tips related to a product, the lists of products
under a certain topic, and the images of a product. Other sub categories for a profile page can be
open to the public selectively by the owner. This study analyzed the contribution category to
obtain data for the variable of contribution of reviewers.
Extrinsic Motivation
The variable of extrinsic motivation is defined as social feedback from fellow customers
for consumer product reviews. Amazon.com provides some interaction functions between
product reviews and review viewers. Each product reviews have the question of “Was this
review helpful to you?” at the review contents with yes and no clickable buttons, and the viewers
can choose one of them. A profile page presents the total amount of the helpful votes a reviewer
received from fellow customers. This study utilized the number to measure the social feedback
from fellow customers.
Preliminary Data Analysis
Factor analysis
Exploratory, principled component factor analysis with Varimax rotation method was
conducted with the data gathered to check internal consistency of the scales employed in this
study. Intrinsic motivational inventory was adjusted with the data set of this study based on the
result of a factory analysis. Intrinsic motivation inventory of Self determination theory is
composed of 4 sub scales, which are interest/enjoyment, perceived choice, perceived competence,
and pressure/tension. Several items were dropped to meet the high level of internal reliability of
the scales. Specifically, an item was dropped if it did not reach the threshold loading of 0.40 on
any factor (Appendix 2. A factor analysis with the Intrinsic Motivation Inventory).A factor
analysis with the data did not load ‘perceived competency’ and ‘pressure/tension’ scales. Thus,
only two sub scales – interest/enjoyment and perceived choice – among the intrinsic motivation
inventory were chosen. The internal reliability coefficients (Cronbach’s alpha) of the scales
are .720 and .849 each, which tell fairly reliable in measuring variables (see Appendix 1).
The same procedure was applied to the scales of personality. An item was dropped if it
does not reach the threshold loading of 0.40 on any. Internal reliability coefficients (Cronbach’s
alpha) of the modified scales turned out to be good – i.e., 0.828 for the autonomy scale, 0.839 for
the controlled orientation, and 0.899 for the impersonal orientation (see Appendix 3).
Normality Test for the dependent variable
To perform a linear or multiple regression, a normality test was conducted with the
dependent variable. Since some respondents in the data have huge amounts of reviews, it caused
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
10
very much skewed distribution in the data of the contribution level variable (a dependent
variable). Thus, the data of the dependent variable was transformed by the logarithm function to
correct the strong right skewness of the variable. Then, a normality test was conducted with the
transformed data. Skeweness of the dependent variable, however, was not corrected despite of
the logarithm data transformation. Thus, some outliers were taken out based on the normal Q-Q
plot of the dependent variable until the data distribution of the dependent variable reaches
acceptable normality, and finally the sample size ended up being 60 (Kolmogorov-Smimov
coefficient, p>.05) (see Appendix 4).
Demographic data of the sample
The respondents consisted of 40 males (66.7%) and 20 females (33.3%). Age distribution
among the respondents showed that 6 respondents are in their twenties (10.0%), 39 in their
thirties (65.0%), 11 in their forties (18.3%), and 4 in their fifties (6.7%). In term of race of the
respondents, 6 respondents are African-American (10.0%), 53 respondents are White/Caucasian
(88.3%), and 1 respondent is Asian/Pacific-Islander (1.6%) (see Table 3).
Table 3
Demographic Statistics of the Respondents
Measure
Value
Frequency
(%)
Gender
Male
Female
Total
40
20
60
66.7
33.3
100%
Age
20-29
30-39
40-49
50-59
Total
6
39
11
4
60
10.0
65.0
18.3
6.7
100%
Race
African-American
6
10.0
White/Caucasian
Hispanic
53
0
88.3
0.0
Asian/Pacific-Islander
Total
1
60
1.6
100%
Table 4
Descriptive Statistics and Correlations of Variables Used
1
2
Variables
Mean
SD
1
2
3
4
Contribution
Interest/Enjoy
43.28
15.88
76.23
2.28
1
.219
1
.216
-.017
.511**
.045
5
6
7
-.014 -.402**
.235 -.173
-.234
-.164
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
3 Perceived Choice
19.08
5.037
4 Helpful Vote
260.33 831.21
5 Autonomy
31.73
4.65
6 Controlled
33.73
6.55
7 Impersonal
38.85
10.38
**. Correlation is significant at the 0.01 level (2-tailed).
a. Listwise N=60
1
-.020
1
11
.381** -.447**
-.044 -.080
1 -.022
1
-.681**
-.078
-.226
.571**
1
A multiple regression with the all the variables involved
Raw values from the all variables were converted into standard scores (z scores) before
being submitted to statistical tests. Among the personality trait variables, the impersonal
orientation variable is highly correlated to the perceived choice variable. Taking both
correlations and collinearity statistics into account, the impersonal orientation in the personality
traits was dropped in the whole statistical tests. A model fit without the impersonal orientation
variable got better. A multiple regression analysis was performed with the five variables – two
intrinsic motivations, one extrinsic motivation, and two personality traits.
All the independent variables accounted for 37.2% (Adjusted R square = .372) of the
variance in the dependent variable in the model. ANOVA test for a model fit showed it is
statistically significant (F 5,54 = 7.991, p < .05). The variables of both the extrinsic motivation
and the controlled orientation among personality traits were statistically significant in predicting
the dependent variable (β = .480, p < .05; β = -.270, p < .05). The significance tests for each
variable are shown below:
Table 5
Results of Multiple Regression Model Predicting Contribution of Consumer Product Reviewers
Model
B
(Constant)
1.593E-016
Helpful Vote
.480
Interest/Enjoyment
.176
1
Perceived Choice
.145
Autonomous
-.095
Controlled
-.270
a. Dependent Variable: Contribution
Coefficientsa
Std. Error
.102
.104
.111
.130
.119
.122
Beta
.480
.176
.145
-.095
-.270
t
.000
4.628
1.589
1.110
-.800
-2.215
Sig.
1.000
.000
.118
.272
.427
.031
To specify the effect of each independent variable on the dependent variable, a
multiple regression analysis was conducted to test hypothesis 1, 2, and 3. Then, for
hypothesis 4-1 and 4-2, mediating effects of intrinsic/extrinsic motivations on the
dependent variable of contribution of consumer product review were tested. The
regression analysis to test mediating effects utilized the macro for bootstrapping for
specific indirect effects in SPSS by Preacher and Hayes (Preacher, K.J. & Hayes, A.F.,
2004).
Results
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
12
Hypotheses Testing
Effect of the intrinsic motivations on the contribution level of consumer product reviews
A multiple regression analysis was conducted to test hypothesis 1 with the two
independent variables of the intrinsic motivations and the dependent variable of contribution of
consumer product reviewers. The result of ANOVA test to see a model fit turned out to be
statistically non-significant (F 57, 59 = 3.047, p < .05). The p value of the model, however,
is .055, thus it could be arguable to say that this model is not significant in a definite way. The
two independent variables of intrinsic motivations accounted for 6.5 % of the variance in the
dependent variable in the model (Adjusted R square = .065). All the two intrinsic motivations
were statistically non significant in predicting the dependent variable (β = .223, p = .082; β = .220, p = .086). Thus, hypothesis 1 was rejected. The results of a multiple regression analysis are
shown below:
Table 6
Results of Multiple Regression with Intrinsic Motivations
Coefficientsa
Model
B
Std. Error
1
(Constant)
-4.541E-16
.125
Interest/Enjoyment
.223
.126
Perceived Choice
.220
.126
a. Dependent Variable: Contribution
Beta
t
.000
1.772
1.748
.223
.220
Sig.
1.000
.082
.086
Effect of the extrinsic motivation on the contribution level of consumer product reviews
A linear regression analysis was conducted to test hypothesis 2 with the independent
variable of the extrinsic motivation and the dependent variable of contribution of consumer
product reviewers. The result of ANOVA test to see a model fit turned out to be statistically
significant (F 58, 59 = 20.527, p < .05). The extrinsic motivation variable accounted for 24.9 %
of the variance in the dependent variable in the model (Adjusted R square = .249). The extrinsic
motivation variable were statistically significant in predicting the dependent variable (β = .511, p
= .000). Thus, hypothesis 2 was accepted. The results of a linear regression analysis are shown
below:
Table 7
Results of Multiple Regression with an Extrinsic Motivation
Coefficientsa
Model
B
Std. Error
(Constant)
-1.737E-17
.112
1
Helpful Vote
.511
.113
a. Dependent Variable: Contribution
Beta
t
.511
.000
4.531
Sig.
1.000
.000
Effect of the personality traits on the contribution level of consumer product reviews
A multiple regression analysis was conducted to test hypothesis 3 with the two
independent variables of the personality traits and the dependent variable of contribution of
consumer product reviewers. The result of ANOVA test to see a model fit turned out to be
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
13
statistically significant (F 57, 59 = 5.500, p < .05). The two independent variables of the
personality traits accounted for 13.2 % of the variance in the dependent variable in the model
(Adjusted R square = .132). Autonomous orientation was statistically non significant in
predicting the dependent variable (β = -.023, p = .849) and controlled orientation was
statistically significant in predicting the dependent variable (β = -.402, p = .002). Thus,
hypothesis 3 was partially accepted. The results of a multiple regression analysis are shown
below:
Table 8
Results Multiple Regression with Personality Traits
Model
1
(Constant)
Autonomous
Controlled
Coefficientsa
B
Std. Error
4.300E-016
.120
-.023
.121
-.402
.121
Beta
t
-.023
-.402
Sig.
.000
-.191
-3.315
1.000
.849
.002
a. Dependent Variable: Zcontri
Mediating effect of intrinsic motivations in the relationship between autonomy orientation
personality trait and contribution level of consumer product reviewers
A multiple mediation regression analysis was conducted to examine a mediating effect of
the intrinsic variables between autonomy orientation personality trait (IV) and contribution level
of consumer product reviewers (DV) using the script for SPSS created by Preacher and Haynes
(2004). A multiple regression model with all independent variables did not show significant
effect of autonomous orientation variable on the dependent variable (See table ). The zeroordered correlation coefficients between autonomous orientation variable and the other
independent variables, however, showed significant relations (See table). Thus, the analysis was
employed to test if mediating effects of the motivation variables on contribution level of
consumer product reviewers for the personality traits variables. A multiple mediation regression
model showed there is statistically significant indirect effect (the amount of mediation) between
autonomous orientation and contribution level of consumer product reviewers mediated by
perceived choice among the intrinsic variables (See Table 9). Thus, hypothesis 4-1 was partially
accepted.
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
Path c
Autonomy Orientation
(X)
Total effect of X on Y
c = -.0141, p = .9147
Contribution Level of
Consumer Product Reviewers
(Y)
Intrinsic Motivations (M)
Direct effect of X on M1
a1 = .2354, p = .0702
Direct effect of X on M2
a2 = .3809, p = .0027
-
Direct effect of M1 on X
b1 = .2689, p = .0425
Direct effect of M 2on X
b2 = .2929, p = .0358
Interest/Enjoy
ment (M1)
Path b
Path a
Autonomy Orientation
(X)
14
Path c’
Direct effect of X on Y
c’ = -.1890, p = .1827
Contribution Level of
Consumer Product
Reviewers (Y)
Figure 2. Results summarizing a multiple mediation regression analysis with the intrinsic
motivations
Table 9
Bootstrap Results for Indirect Effects of IV on DV through the intrinsic motivations
Total
Interest/Enjoyment
Perceived Choice
Data
boot
Bias
SE
.1749*
.0633
.1116*
.1759
.0617
.1141
.0010
-.0016
.0026
.0884
.0561
.0704
Bias Corrected and Accelerated 95%
Confidence Intervals
Lower
Upper
.0426
.4047
-.0121
.2345
.0080
.2888
* If zero is not in the confidence interval
Mediating effect of an extrinsic motivation in the relationship between controlled
orientation as a personality trait and contribution level of consumer product reviewers
The analysis was employed to test if a mediating effect of the extrinsic motivation
variable on contribution level of consumer product reviewers for the personality traits variables.
A multiple mediation regression model showed there is not statistically significant indirect effect
between controlled orientation and contribution level of consumer product reviewers mediated
by the extrinsic motivation (positive social feedback from fellow customer) (see Table 10). Thus,
hypothesis 4-2 was rejected.
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
Path c
Controlled Orientation
(X)
Total effect of X on Y
c = -.4015, p = .0015
Contribution Level of
Consumer Product Reviewers
(Y)
Direct effect of M
b = .4821, p = .0000
Extrinsic Motivations
- Positive Social
Feedback (M)
Direct effect of X on M1
a1 = -.0804, p = .5415
Path b
Path a
Controlled Orientation
(X)
15
Path c’
Direct effect of X on Y
c’ = -.3628, p = .0009
Contribution Level of
Consumer Product
Reviewers (Y)
Figure 3. Results summarizing a multiple mediation regression analysis with the social feedback
Table 10
Bootstrap Results for Indirect Effects of IV on DV through the Social Feedback
Data
boot
Total
-.0388
-.0562
Positive Social
-.0388
-.0562
Feedback
* If zero is not in the confidence interval
Bias
SE
-.0174
-.0174
.0680
.0680
Bias Corrected and Accelerated 95%
Confidence Intervals
Lower
Upper
-.1665
.0821
-.1665
.0821
Discussion
The goal of this study was to explore what motivates contributors to consumer product
reviews. Based on the Self Determination Theory by Deci & Ryan (1985), this study
hypothesized the effects of personality traits (autonomous and controlled orientation), intrinsic
motivations (interest/enjoyment and perceived choice), and an extrinsic motivation (positive
social feedback from fellow customers) on contribution of consumer product reviewers. In
addition to find the individual effects of the three constructs, this study hypothesized the
mediating relationship among the independent variables in predicting the contribution of
consumer product reviews. In specific, it was hypothesized that human motivations – intrinsic as
well as extrinsic – would mediate the personality traits in predicting the contribution level of
consumer product reviewers.
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
16
The results supported the hypotheses that the personality traits and the extrinsic
motivation have the effect on contribution of consumer product reviewers. In particular, the
controlled orientation had a negative effect on contribution of consumer product reviews whereas
the autonomous orientation did not have statistically significant effect on contribution of
consumer product reviewers. Individual behavior with controlled orientation is under influence
of external rewards. That is, individuals with high level of controlled orientation are less likely to
participate in writing product reviews. Also, positive feedbacks from fellow customers predict
the contribution of consumer product review well. The more helpful votes a contributor receives,
the more likely the contributor has the larger amount of product reviews. These results are partly
consistent to those of the study of motivation of the Amazon top reviewers by Peddibhotla and
Subramani (2007). They found that self interested motivations (e.g., self-expression or getting
tangible rewards/recognition from others) are positively related to the quantity of product
reviews. Taken together, these findings tell that external rewards or extrinsic motivations are
better predictable variables for the contribution behavior of consumer product reviewers rather
than self motivated autonomous orientation or intrinsic motivations (e.g., interest/enjoyment and
perceived choice).
This study hypothesized the mediating effects of intrinsic motivations/an extrinsic
motivation in the relationship between personality traits and contribution of consumer product
reviews. The results supported the mediating role of intrinsic motivations (interest/enjoyment
and perceived choice) in the relationship between autonomous orientation and contribution level
of consumer product reviewers, but did not support the mediating role of an extrinsic motivation
in the relationship between controlled orientation and contribution level of consumer product
reviewers.
In a multiple regression model with the five independent variables, autonomous
orientation and intrinsic motivations among others turned out to be statistically non-significant in
predicting the dependent variable. The results of the mediation regression analysis showed the
two variables do have indirect effects on the dependent variable. That is, autonomous orientation
predicts the intrinsic motivations (interest/enjoyment and perceived choice) and then, the
intrinsic motivations predict the dependent variable (contribution of consumer product reviews)
in turn. Unlike the previous empirical studies suggested self interested intrinsic motivations
(interest, fun, or self-expression) have direct effects on contribution of consumer product reviews,
this study found that the intrinsic motivations have indirect effects on it mediating a self
motivated personality trait like autonomy. This point could be considered as the unique
contribution to the field of this study.
Limitations of this study have the small size of samples; the samples of this study were
product reviewers at Amazon. One disadvantage was that it was hard to find the population of
Amazon reviewers; this study chose a convenience sampling technique utilizing customer
discussion boards to access to reviewers. Also, the survey recruited the subjects voluntarily.
These limitations bring a weakness in generalizing the findings of this study to the population.
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
17
References
Burke, M., Marlow, C., and Lento, T. (2009). Feed Me: Motivating Newcomer Contribution in
Social Network Sites. Paper presented at the CHI 2009, M.A. Boston.
Chevalier, J. A., & Mayzlin, D. (2006). The effect of word of mouth on sales: Online book
reviews. Journal of Marketing Research, 43(3), 345-354.
Cliff Lampe, E. J. (2005). Follow the (Slash) dot: Effects of Feedback on New Members in an
Online Community. Paper presented at the GROUP’05, Sanibel Island, Florida, USA.
Deci, E. L., & Ryan, R. M. (1985a). Intrinsic motivation and self-determination in human
behavior. New York: Plenum.
Deci, E. L., & Ryan, R. M. (1985b). THE GENERAL CAUSALITY ORIENTATIONS SCALE
- SELF-DETERMINATION IN PERSONALITY. Journal of Research in Personality,
19(2), 109-134.
Elisabeth Joyce1, R. E. K. (2006). Predicting Continued Participation in Newsgroups - Joyce 2006 - Journal of Computer-Mediated Communication - Wiley Online Library. Journal
of Computer-Mediated Communication, 11(3), 723–747.
Forman, C., Ghose, A., & Wiesenfeld, B. (2008). Examining the relationship between reviews
and sales: The role of reviewer identity disclosure in electronic markets. Information
Systems Research, 19(3), 291-313. doi: 10.1287/isre.1080.0193
Peddibhotla, N. B., & Subramani, M. R. (2007). Contributing to public document repositories: A
critical mass theory perspective. Organization Studies, 28(3), 327-346. doi:
10.1177/0170840607076002
Preacher, K. J., & Hayes, A. F. (2008). Asympotic and resampling procedures for assessing and
comparing indirect effects in multiple mediator models. Behavior Research Methods, 40,
879-89
Ryan, R. M., & Deci, E. L. (2000). Intrinsic and extrinsic motivations: Classic definitions and
new directions. Contemporary Educational Psychology, 25(1), 54-67.
Ryan, R. M., & Grolnick, W. S. (1986). ORIGINS AND PAWNS IN THE CLASSROOM SELF-REPORT AND PROJECTIVE ASSESSMENTS OF INDIVIDUALDIFFERENCES IN CHILDRENS PERCEPTIONS. Journal of Personality and Social
Psychology, 50(3), 550-558.
Rucker, D.D., Preacher, K.J., Tormala, Z.L., & Petty, R.E. (2011). Mediation Analysis in Social
Psychology: Current Practices and New Recommendations. Social and Personality
Psychology Compass, 5(6)
Zhu, F., & Zhang, X. Q. (2010). Impact of Online Consumer Reviews on Sales: The Moderating
Role of Product and Consumer Characteristics. Journal of Marketing, 74(2), 133-148.
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
18
Appendices
Appendix 1. Modified scales: Intrinsic Motivations and Personality Traits
Table 1
Modified intrinsic motivation inventory in the Self determination theory
Factor
Interest/enjoyment
Perceived Choice
Items
(1) I enjoyed writing reviews very much.
(2) I thought writing reviews was very interesting.
(3) I would describe writing reviews as very enjoyable
(1) I felt that it was my choice to write reviews.
(2) I didn’t really have a choice about writing reviews.
(3) I felt like I had to write reviews
(4) I wrote reviews because I had no choice.
Cronbach’s Alpha
.720
.849
Table 2
Modified scales of personality traits in the Self determination theory
Personality traits
Autonomy orientation
Controlled orientation
Impersonal orientation
Items
(1) Talk it over with your daughter to understand further
what the problem is.
(2) Share your observations with him/her and try to find
out what is going on for him/her.
(3) You’ll find some people with whom you can relate.
(4) How interested you are in that kind of work.
(5) Ask her about the problem and let her know you are
available to help work it out.
(6) Feel interested in the new challenge and a little
nervous at the same time.
(1) It’s not what you know, but who you know.
(2) Simply assigning times that each can have a coffee
break to avoid any problems.
(3) Take charge: that is, you would make most of the
major decisions yourself.
(4) The other person probably did the right things
“politically” to get the job.
(5) Whether there are good possibilities for advancement.
(6) Tell her that work is below what is expected and that
she should start working harder.
(7) Feel excited about the higher status and salary that is
involved.
(1) Scold her and hope she does better.
(2) I’m probably not good enough for the job.
(3) Ignore it because there’s not much you can do about it
anyway.
(4) “I can’t do anything right,” and feel sad.
Cronbach’s Alpha
.828
.839
.899
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
(5) You’ll probably feel somewhat isolated and
unnoticed.
(6) You didn’t really expect the job; you frequently get
passed over.
(7) Whether you can do the work without getting in over
your head.
(8) It’s hard to know what to do to get her straightened
out.
(9) Feel stressed and anxious about the upcoming
changes.
19
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
20
Appendix 2. A Factor analysis for Intrinsic Motivation Inventory
Total Variance Explained
Initial Eigenvalues
Rotation Sums of Squared Loadings
Total
% of Variance Cumulative %
Total
% of Variance Cumulative %
1
5.965
27.115
27.115
5.756
26.163
26.163
2
3.959
17.996
45.111
2.551
11.598
37.761
3
1.932
8.783
53.894
2.091
9.504
47.265
4
1.550
7.044
60.938
1.990
9.047
56.312
5
1.462
6.644
67.583
1.906
8.665
64.977
6
1.114
5.066
72.648
1.688
7.671
72.648
7
.939
4.267
76.916
8
.728
3.308
80.224
9
.632
2.874
83.098
10
.557
2.530
85.628
dim
11
.496
2.256
87.884
ensi
12
.489
2.221
90.105
on0
13
.449
2.041
92.146
14
.380
1.725
93.871
15
.281
1.279
95.150
16
.246
1.119
96.269
17
.221
1.005
97.274
18
.199
.902
98.176
19
.134
.608
98.784
20
.110
.502
99.287
21
.085
.387
99.673
22
.072
.327
100.000
Extraction Method: Principal Component Analysis.
Component
q4I
q8I
q11i
q13I
q17RI
q20I
q23I
q6CH
q14RCH
q18CH
q22RCH
q24RCH
q7C
q10C
q15C
q19C
q25C
q5RP
1
-.010
.039
-.140
-.067
.872
.379
-.178
.399
.898
.084
.766
.888
.335
-.448
.080
-.096
-.101
-.078
Rotated Component Matrixa
Component
2
3
4
.081
.075
-.132
.072
-.011
.781
.247
-.010
.141
.757
-.058
.274
.045
-.036
-.040
.634
-.062
-.091
.748
.323
.016
.073
.645
.316
-.019
.204
.003
.157
.894
.035
-.179
.262
.022
.000
.006
.153
.148
-.268
.633
.240
.164
.230
.057
.080
.189
.188
-.065
.220
.124
.246
.746
-.028
-.629
.106
5
6
.005
.326
.800
.281
.009
.247
.203
-.274
-.006
-.049
-.173
-.026
.066
.353
.076
.712
.016
-.456
.737
-.195
-.183
.078
.123
.005
.084
.034
-.057
.037
-.025
-.101
.304
.207
.839
.317
.061
-.243
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
q9P
-.831
-.213
.036
-.066
q12RP
.000
-.828
-.096
-.134
q16P
-.817
-.036
.087
.068
q21P
-.862
.117
-.249
-.043
Extraction Method: Principal Component Analysis.
Rotation Method: Varimax with Kaiser Normalization.
a. Rotation converged in 7 iterations.
-.006
.063
.122
.051
-.086
-.067
-.114
-.004
21
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
22
Appendix 3. A Factor analysis for Personality Traits
Total Variance Explained
Initial Eigenvalues
Rotation Sums of Squared Loadings
Total
% of Variance Cumulative %
Total
% of Variance Cumulative %
1
9.521
27.203
27.203
6.211
17.747
17.747
2
5.535
15.815
43.018
3.861
11.032
28.779
3
3.001
8.573
51.591
3.556
10.161
38.941
4
2.298
6.566
58.158
3.415
9.757
48.698
5
1.947
5.564
63.722
3.286
9.389
58.088
6
1.588
4.538
68.260
2.492
7.120
65.208
7
1.388
3.966
72.226
1.710
4.885
70.094
8
1.279
3.653
75.879
1.662
4.750
74.843
9
1.046
2.989
78.868
1.409
4.025
78.868
10
.808
2.309
81.177
11
.735
2.099
83.276
12
.690
1.971
85.246
13
.666
1.903
87.149
14
.557
1.591
88.740
15
.465
1.329
90.070
16
.427
1.219
91.288
dim 17
.347
.992
92.280
ensi 18
.342
.978
93.258
on0 19
.321
.917
94.174
20
.278
.795
94.970
21
.269
.770
95.739
22
.247
.704
96.444
23
.222
.633
97.077
24
.186
.533
97.610
25
.165
.470
98.080
26
.148
.423
98.503
27
.116
.332
98.835
28
.104
.298
99.132
29
.088
.252
99.384
30
.070
.199
99.584
31
.050
.142
99.726
32
.033
.094
99.820
33
.031
.090
99.910
34
.020
.058
99.968
35
.011
.032
100.000
Extraction Method: Principal Component Analysis.
Component
q28AUTO
q29AUTO
q34auto
q35auto
q38auto
1
2
.199
.054
.141
.209
-.172
.067
-.012
-.088
-.645
-.003
Rotated Component Matrixa
Component
3
4
5
6
.311
.279
.168
.439
-.077
.718
-.327
.372
.106
.304
-.042
.241
.093
.131
.487
.182
.032
.795
.076
.000
7
.102
.126
.042
.088
-.006
8
-.085
-.009
-.088
-.077
-.021
9
-.503
-.149
.775
.231
.334
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
q42auto
-.141
.025
-.276
.001
q45auto
-.160
.017
.218
.787
q49auto
-.158
-.030
.052
.279
q52auto
.052
.105
.344
.337
q54auto
-.254
-.037
.109
.450
q57auto
-.106
-.147
-.027
.467
q59auto
.001
.079
.312
.439
q27CON
.027
.034
.224
.215
q31CON
.154
.304
.727
.000
q32CON
.727
.414
.048
.170
q36con
.230
.790
.186
-.120
q40con
.280
.047
.207
-.169
q43con
.716
-.009
.069
-.424
q44con
.178
.191
.725
.085
q47con
.432
.483
.471
-.106
q51con
.135
.326
.094
-.140
q55con
-.070
.516
.675
.219
q56con
.175
.800
.217
-.037
q60con
.158
.720
.129
.364
q30IM
.756
.102
.044
-.197
Q33im
.385
.232
.162
.108
q37im
.334
-.048
.719
.054
q39im
.739
.295
.030
-.117
q41im
.647
.249
.167
-.100
q46im
.813
-.111
.055
-.020
q48im
.315
.618
.200
-.055
q50im
.601
.061
.324
-.012
q53im
.488
.254
.487
.154
q58im
.776
-.079
.409
-.161
q61im
.823
.127
.119
.093
Extraction Method: Principal Component Analysis.
Rotation Method: Varimax with Kaiser Normalization.
a. Rotation converged in 13 iterations.
.236
-.038
-.132
-.549
-.168
-.278
-.584
-.058
-.236
.344
-.064
.819
.283
.233
-.098
.073
.028
.117
.182
.170
.716
.258
.043
.248
.058
.480
.306
.012
.154
-.107
.693
.190
.753
.178
.496
.471
.073
-.003
.201
-.126
-.227
-.043
-.072
-.286
-.049
-.019
.061
.122
.196
-.260
.006
.031
-.121
.111
-.023
-.033
-.112
-.159
-.209
.212
23
.423
.268
-.094
.066
-.185
-.175
.217
.852
.198
-.046
.141
-.013
.102
-.070
.316
-.031
.017
-.043
-.187
.165
-.013
.160
.125
-.355
-.106
.183
.155
-.278
.045
-.122
.068
-.097
-.029
-.382
-.250
.437
-.296
-.075
.039
.001
.005
.081
.190
.233
-.071
.779
-.049
.204
.081
.058
-.214
-.046
-.041
-.231
.375
.054
.334
-.062
-.067
-.069
.169
.006
.043
.038
.168
-.007
.045
.001
-.020
-.028
-.114
-.105
.014
.105
-.134
-.045
-.165
.227
-.117
.055
-.017
.057
.015
.049
-.193
.078
.203
.245
-.014
.055
MEDIATING ROLE OF MOTIVATIONS IN PRODUCT REVIEWS
24
Appendix 4. Data transformation of Contribution Level of Consumer Product Reviews
Minimu
m
N
Contributions
HelpfulVote
logContributiio
ns
logHelpfulness
Valid N
(listwise)
Descriptive Statistics
Maximu
Std.
m
Mean
Deviation
Statistic Statistic Statistic Statistic
85
1
424
30.96
85
0
5750 188.75
85
.00
6.05 2.0439
79
79
.00
8.66
3.1827
Skewness
Kurtosis
Std.
Std.
Statistic
Statistic
Error
Statistic
Error
66.706
3.878
.261 17.371
.517
705.934
6.493
.261 47.676
.517
1.64317
.501
.261
-.674
.517
1.91234
Tests of Normality
Kolmogorov-Smirnova
Shapiro-Wilk
Statistic
df
Sig.
Statistic
df
logHelpfulness
.080
79
.200*
.969
79
logContributiions
.117
79
.009
.947
79
a. Lilliefors Significance Correction
*. This is a lower bound of the true significance.
.589
Sig.
.051
.003
.271
.136
.535