User Satisfaction Prespective
Dimitrios I. Rigas and Mutlaq B. Alotaibi
Department of computing, University of Bradford, Bradford, West Yorkshire, BD7 1DP, U.K.
Keywords: Customer, Knowledge, Multimodal, Interaction, Satisfaction, Sound, Speech, Earcons, Auditory Icons,
Abstract: The purpose of this paper was to examine the implications of employing multimodal user interaction in
Electronic Customer Knowledge Management Systems (E-CKMS). There are various challenges to E-
CKMS mentioned in current literature and reported (trust and knowledge hoarding, structured transfer of
knowledge and content and relevancy issues). As empirical CKM studies that examine the role of
multimodal interaction in this field are generally lacking, this paper reports research conducted to evaluate
this role and measure user satisfaction. This evaluation was undertaken empirically by developing two E-
CKMS experimental platforms (text with graphics only and multimodal). The major findings indicated that
user satisfaction was significantly improved by using multimodal metaphors. Further investigation is needed
to determine the usefulness of two multimodal versions on E-CKMS instead of comparing text with
graphics only with multimodal.
The new means of IT, such as internet, extranets and
intranets, leads to dramatic shift from information to
knowledge societies (Thierauf, 1999, Goh, 2005).
Harnessing invisible assets is becoming one of the
primary sources of creating value and competitive
advantage in the current age of knowledge (Goh,
2005). Knowledge as a concept covers vast area of
various views (Becerra-Fernandez et al., 2004),
levels (Davenport and Prusak, 1998, Rowley, 2002),
principles (Such et al., 2001), taxonomies
(Davenport and Prusak, 1998, Thierauf, 1999, Hahn
and Subramani, 2000), strategies and trends. One
classification of knowledge is based on the source
from which knowledge has been elicited (external
and internal) (Davenport and Prusak, 1998).
External knowledge (CK) can be regarded as one of
the most organisations valuable types of knowledge
(Osterle, 1995), which is gathered at the customer
point of contact under a great deal of time pressure
(Lesser et al., 2000). The Utilisation of CK helps
organisations to grow, innovate and compete against
competitors (Gebert et al., 2002a, Gebert et al.,
2002b), but it is not easy to gather, identify, interpret
and integrate, because it flows to the organisation
form multiple communication channels (Bueren,
2005). This led to integrating both Knowledge
Management (KM) and Customer Relationship
Management (CRM) in E-Business contexts. More
details on the determination and characteristics of
KM, CRM and E-Business can be found in (Becerra-
Fernandez et al., 2004, Tiwana, 2001, Skyrme, 2001,
Alotaibi and Alzahrani, 2004).
E-CKMS is derived from the integration between
KM and CRM in E-Business (Tiwana, 2001), and its
typical example is represented in Amazon case study
(Gebert et al., 2002b, Gurgul et al., 2002, Rollins
and Halinen, 2005), which illustrates how
Communities of Customers (CoC) works. There are
several similarities between CoC and Communities
of Practice (CoP), which mean that CoC is rooted in
the traditional KM (Lesser et al., 2000, Gurgul et al.,
2002). In CoC, peer customers share opinions and
insights about products and services, which can lead
to more effective and guided decisions made by any
member of this community (Gibbert et al., 2002).
From CRM point of view, storing and analysing
customer historical transactions leads to
understanding customer buying patterns, and hence
leveraging up-selling and cross-selling opportunities
(Tiwana, 2001, Pan and Lee, 2003). Amazon case
study involves KM and CRM aspects that can be
I. Rigas D. and B. Alotaibi M. (2008).
In Proceedings of the International Conference on e-Business, pages 143-148
DOI: 10.5220/0001903801430148
benchmarked by efforts devoted to evaluating E-
CKMS. Interactive systems can be seen as one of the
CRM components that enable E-CKM by
establishing learning relationship (learn while
interact) (Massey et al., 2001). Interacting with
customers in real-time and adopting CoC can be
counted among several proposed approaches that
improve the elicitation (Gibbert et al., 2002), expand
the exploitation (Lesser et al., 2000) of CK, reduce
cost, and hence replace the traditional approach that
rely on understanding of sales representatives or
results market research.
There were several challenges to E-CKMS that
can be tackled using the interactive multimodal
metaphors. Knowledge hoarding (Davenport and
Prusak, 1998, Gibbert et al., 2002), for example, can
be seen as the lack of customer willingness to share
knowledge, and solved by several approaches that
include optimising customer-company dialogue
(Interaction) (Massey et al., 2001, Gurgul et al.,
2002, Gibbert et al., 2002). Gibbert et al. (2002)
stated that trust and knowledge hoarding could be
tackled by not only establishing continuous two-way
dialog with customers, but also employing
interactive multimedia systems. Another challenge is
that customers when interacting with E-CKMS
needs to have their ideas well-structured and
organised, which can be aided by what so-called
Customer Innovation Toolkits (CIT) (von Hippel,
2001b, Von Hippel, 2001a). CIT can be incorporated
into E-CKMS in order to facilitate an optimal
transformation of customer expertise and
expectations (knowledge sharing) into valuable
suggestions, which can be afterward used to offer
customised and personalised products and services.
This context involves knowledge sharing, and hence
encouraging customer to share knowledge is needed,
which leads to the assumption that there is a
potential role for multimodal interaction metaphors
to play. Another challenge is information overload
and relevancy, which is, actually derived the web-
based environment. Authors (Davenport and Prusak,
1998, Bueren, 2005) in E-CKMS field raises
information overload and relevancy as a concern,
and include it with content issues, but some mention
identification of relevant knowledge (Urban and von
Hippel, 1988). Brewster (1997) argued that this
could be addressed by enhancing the text with
graphics only manner of information display with
means of auditory metaphors (Brewster, 1997). To
sum up, multimodal interaction is anticipated to
address trust, structure and content questions in E-
The remainder of the paper is organised in seven
sections. In Section 2, we introduced relevant work.
Section 3 described the experimental platform.
Design of the empirical study is shown in Section 4.
In Section 5, we presented results and discussion.
Conclusion is provided in Section 6. Finally, we
described future work in Section 7.
Researchers in the CKM field tend to analyse CKM
case studies, identify cultural, structural and
managerial mechanisms that facilitate CKM success
and propose models and frameworks for theory and
practice. García-Murillo and Annabi (2002)
proposed a model of social relationships, and put
emphasis on interpreting knowledge directly by
human (García-Murillo and Annabi, 2002). Some
other authors consider structural aspects, such as
organisational boundaries, culture, structure and
climate (Bose and Sugumaran, 2003, Dous et al.,
2005, Bueren, 2005). Others look at rewards
systems, incentives, management support and
perception (Gibbert et al., 2002, Gurgul et al., 2002).
In addition, there were several authors who
discussed CK characteristics, approaches,
applications and relations (Feng and Tian, 2005,
Lesser et al., 2000, Rowley, 2002, Skyrme, 2001).
Business Engineering (BE) (Osterle, 1995)
perspective suggests separating strategy, process,
system and change levels (Bose and Sugumaran,
2003, Dous et al., 2005, Bueren, 2005). Several
studies presented styles of CKM and types of CK
(Gibbert et al., 2002, Gurgul et al., 2002, Feng and
Tian, 2005, Rowley, 2002). Although, these studies
commonly studied CK based on several perspectives
and points of view, other than empirically examining
the role of multimodal interaction, it provided
insights into the underlying principles and
theoretical foundations of E-CKMS.
There is little known about efforts in CKM field
has been devoted to evaluate the potential role that
multimodal metaphors can play in E-CKMS.
Nevertheless, a great deal of studies in several fields
of study have been conducted to evaluate such role,
and found that user interface can be improved by the
augment of speech (Kehoe and Pitt, 2006)
(synthesised and recorded speech) and non-speech
sounds (earcons (Rigas et al., 2000, Rigas and Alty,
2005) and auditory icons (Gaver, 1997, Cohen,
1993). In software engineering, There were several
studies that support this view, such as (Sonnenwald
et al., 1990, Cohen and Ludwig, 1991, DiGiano et
al., 1993, Rigas et al., 1997, Rigas and Alty, 1998).
Overall, user satisfaction and other usability
ICE-B 2008 - International Conference on e-Business
attributes can be improved in general Information
Systems (IS) by employing multimodal interaction.
Table 1: E-CKMS visual and auditory metaphors.
CK category T G T G S E A R
Trends (top 10)
Customer rating
Website advice
Burke et al. (2006) carried out meta-analysis
investigation into the effectiveness of multimodal
interaction, in forty three studies, and found that
audio-visual metaphors have a significant role to
play in improving user performance in IS compared
to the visual-only display. In addition, this finding
was supported by the results obtained from two
experiments carried out by (Rigas and Memery,
2002), who investigated the use of auditory stimuli
(speech, earcons and auditory icons) to communicate
information to users in both email and stock control
applications. Additionally, two studies (Rigas and
Alty, 2005, Alty and Rigas, 2005) investigated
utilising rising pitch metaphors in the
communication of graphical information, and found
that it was possible for visually-impaired users to
interpret graphical information with the aid of rising
pitch metaphors, even in the absence of a visual
Since E-CKMS is a web-based environment, it
can be linked to similar fields of study, such as web-
based browsing and email applications (Rigas and
Memery, 2002, Rigas and Memery, 2003, Rigas,
2003). In web-based browsing systems, a prototype
has been develop as an online help system with
sound support (Kehoe and Pitt, 2006), and extended
later by incorporating no-speech sound and other
auditory metaphors (Kehoe et al., 2007). In addition,
another web-based browsing prototype was built to
browse musical notes with the help of sound, and
proven successful performance improvement
(Fernström and McNamara, 2005). In email
applications, several experiments (Rigas and
Memery, 2002, Rigas and Memery, 2003, Rigas,
2003) were conducted to evaluate the potential of
audio-visual metaphors in reducing visual
complexity and tackling information hiding, and
concluded that this hypothesis was true, besides that
visual display have to be synchronised with means
of auditory stimuli.
The experimental platform developed for this
research provided typical functions of web-based
mobile phones retailing systems, and included an
additional function labelled as co-production, which
defined by (Gibbert et al., 2002) as the manner in
which customers practice New Product
Development (NPD). Typically, E-CKMS consists
of three main components: CKM, infrastructural and
user interface components, and can incorporate any
additional function, such as the one included in this
study (co-production). This study assumed that
CKM and infrastructural components were
previously implemented.
Co-production function facilitates the dual role
of customers (producer and consumer) by offering
CIT that aid customers to manipulate elements in
solution space to test new products (billing scheme).
In fact, solution space included several elements, but
the scope of this study limited these elements to
loyalty, billing and taffies schemes. Furthermore, co-
production function offered a trail-and-error engine
that enabled experimental NPD, allowed its
repetition until final product design was reached.
This engine received customised schemes from CIT,
sent it to billing engine, received customised bill,
stored it in trails comparison array and provided
comparison of results obtained from other trails in
order to support customer decision making.
This platform was implemented with two
interfaces. These two versions were text with
graphics only E-CKMS (VCKMS) and Multimodal
communicated to E-CKMS users using text with
graphics only, while the communication method was
audio-visual in MCKMS. The communication of CK
required classification of CK and auditory and visual
metaphors, and utilisation of a wide range of
technologies. First, Types of CK were organised into
six categories (trends, customer reviews, customer
ratings, website advices, co-production CK and
product features). Some of these CK were
communicated visually, auditory or simultaneously.
Second, the visual metaphors employed were text
(T) and Graphic (G), whilst the auditory metaphors
were synthesised speech (S), earcons (E), auditory
icons (A) and recoded speech (R). Table 1 shows
each CK category and the way by which it was
KNOWLEDGE - User Satisfaction Prespective
The research undertook explored customer
satisfaction aspects related to the use of audio-visual
metaphors in three levels of task complexity.
Table 2: Summary of task levels influential factors.
CKMA Complexity factors
E A1 A2 L L 10 40
M A3 A4 A5 M M 15 17
D A6 A7 A8 H H 17 4
The three levels are task easy (Task E), task
moderate (Task M) and task difficult (Task D). In
this study, task levels were created based on six
influential factors: number of task requirements
(NOTR), number of available selections (NOAS),
number of CKM activities (CKMA), customer
Interaction (CI) and CK intensity (CKI). If the task
was to be designed as difficult, NOTR, CKMA, CKI
and CI needed to be increased, while NOAS was to
be decreased. In CKMA factor, there have been a
various types of CKMA: phone selection activity
(PSA), tariff selection activity (TSA) and Co-
production activity (CPR). In CKI and CI factors,
there were three important levels: low (L), moderate
(M) and high (H). Table 2 reviews the task
complexity influential factors, and illustrates the
association between tasks and CKMA. More
information on task levels, types and workload is
provided on (Burke et al., 2006).
Forty subjects (all were students at University of
Bradford, and regular internet users) were selected
randomly, based on the non-probability sampling
strategy (convenience-sampling method) (Salkind,
2006b). Subjects were divided into two groups (20
each): control and experimental, and then offered a
short training session on the corresponding version
of E-CKMS. Subsequently, subjects were asked to
perform the three tasks and then fill a questionnaire
devised for this study. The order of tasks was
counterbalanced between participants in order to
neutralize possible task learning effect.
Satisfaction was measured by a set of user provided
answers to questionnaire questions, which include
ease of the system (EOS), extent of user confusion
(EOC), extent of user frustration (EOF), ease of
navigation (EON) and overall comfort (COM).
Measuring user attitude towards the system appears
to be difficult. However, asking to specify the
extent, to which the user agree or disagree with a set
of statements, tend to support the pursuit of this
measurement (Jordan, 1998).
Table 3: The mode and frequency values of the five
aspects of customer satisfaction.
Group Value
Aspects of customer satisfaction
Mode 4 3 3 5 5
Freq. 50% 40% 45% 85% 55%
Mode 5 2 2 5 5
Freq. 70% 55% 50% 65% 65%
User agreement and disagreement utilised a six-
point scale ranging from agree strongly to disagree
strongly (Salkind, 2006a). The values of the scale
were six for strong agreement, five for moderate
agreement, four for slight agreement, three for slight
disagreement, two for moderate disagreement and
one for strong disagreement. After completing all
user satisfaction questions, responses were summed
up to generate an overall score for user satisfaction,
based on the system usability scale (SUS) (Brooke,
It was noteworthy that multimodal interaction
reduced customer response time, which led to
greater customer satisfaction and eventually loyalty.
Participants in the experimental group expressed
interest in CK communicated aurally more than
those in the control one. Our experience with this
platform suggested that users tend to be more
comfortable with aural communication when sounds
conveyed more rapidly than for the first time. At
first glance, the mean value of customer satisfaction
for using MCKMS (77%) was higher than that for
VCKMS (63%). Significance of the difference
between the two conditions was tested (at 0.05
significance level) using the t-test. The difference
was found significant (t
= 4, CV= 2.03 P < 0.05).
Table 3 shows the mode values for the aspects of
user satisfaction with the values for using VCKMS
and MCKMS, in addition to the frequency of the
mode. User responses suggested that the multimodal
E-CKMS is easier to use, less confusing and less
frustrating. In fact, 70% of users agreed moderately
that the multimodal system was easy to use
compared to 50% agreed slightly that the text with
graphics only version was easy to use. In user
confusion and frustration, half of the sample agreed
ICE-B 2008 - International Conference on e-Business
moderately that the multimodal E-CKMS is neither
confusing nor frustrating, in comparison to 40% and
45% of users disagree slightly that the text with
graphics only version was confusing and frustrating
respectively. Furthermore, Mann-Whitney statistical
test was performed, and showed that there were
significant differences in all aspect of customer
satisfaction expect in the ease of navigation.
The role E-CKM has become increasingly important
to public and private organisations due to the cost
savings it offers. However, it is considerably
complex, vague and challenging discipline due to
the many aspects involved. This study shed light into
three challenges to E-CKMS (trust and knowledge
hoarding, structured knowledge transformation and
content and relevancy issues), which can be tackled
by utilising multimodal metaphors. This hypothesis
was tested empirically by two independent groups in
two E-CKMS. Subjects took part in this research
were satisfied and expressed interest in the use of
audio-visual metaphors. The significance of this
approach was found in all aspects of customer
satisfaction, except in the ease of navigation.
Therefore, it can be concluded that audio-visual
metaphors has contributed positively towards the
improvement of customer satisfaction. In summary,
results showed that the use of multimodal interactive
metaphors in E-CKMS is more satisfactory than to
text with graphics display.
This experiment reported here proved to be
successful. However, it was noticed during the
previous experiments that users tend not to take into
account various types of presented CK, such as
customer ratings and reviews. Therefore, further
investigation into additional multimodal metaphors
is needed to determine how speech with aviator can
promotes further utilisation of customer reviews, and
this is expected to yield a set of useful guidelines.
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