Usability for Blended Shopping
Solving Major Flaws by Applying Usability Engineering and Proven Integration
Technologies
Britta Fuchs and Thomas Ritz
Department of Electrical Engineering and Information Technology,
FH Aachen, Eupener Str. 70, 52066 Aachen, Germany
Keywords: Blended Shopping, Usability, QR-Code.
Abstract: The relevance of usability with regard to Blended Shopping concepts is addressed in this paper. First an
introduction into usability as a crucial acceptance factor for applications is given. Then Blended Shopping -
the combination of traditional retail and eCommerce – in practice is analyzed. Research findings presented
reveal that merchants do not apply Blended Shopping concepts in practice until now. It is assumed that
usability flaws are one of the main barriers for Blended Shopping. Different dimensions of usability
problems that prohibit a wide acceptance among users are explained and analyzed. Then a methodological
approach is suggested to address vertical problems. A technology-driven approach to address horizontal
problems is described. The paper will close with a future outlook.
1 INTRODUCTION
During the past few years it became subject of
research to combine traditional retail and
eCommerce. Approaches like Blended Shopping
(e.g. Fuchs & Ritz, 2009a; Fuchs & Ritz, 2009b;
Fuchs & Ritz, 2011) focus on this issue. In the
article at hand we introduce related usability issues
and closely examine missing interaction standards
for Blended Shopping applications.
We start with an brief introduction into usability
and engineering methods to guarantee a high level of
usability, which is crucial for a significant
acceptance level of IT soluctions. Then Blended
Shopping is introduced. A short overview of
Blended Shopping field studies is given. The
analysis of research results reveals that there is a
lack in conformance with users expectations which
is a major usability demand. The reasons for this are
investigated in this paper. Next to a lack in
interaction standards and patterns we assume that
especially the technical integration of mobile
Commerce solution in the physical shopping world
does not respect usability issues. QR Codes as one
representative connecting technology is investigated
in more detail. the paper delivers methodological
approaches to cope with different dimensions of
usability problems. The proposed methods would
result in a significant higher level of fulfillment with
user expectations and emphasize the ease-of-
learning paradigm for the use of QR-Codes as
integration technology between virtual and physical
world. The paper ends with an outlook on future
research.
2 USABILITY
Acceptance and success of software solutions
depend i.a. on usability. Usability refers to “the
degree of effectiveness, efficiency, and satisfaction
with which specified users can achieve specified
goals in particular environments” (see DIN/ISO
9241-11). Effectiveness is understood as the
accuracy and completeness with which specified
users can achieve specified goals in particular
environments. Efficiency describes the resources
expended in relation to the accuracy and
completeness of goals achieved. Satisfaction means
the comfort and acceptability of the work system to
its users and other people affected by its use. In this
context, process models have been established that
consider usability as a performance measure
throughout the entire product life cycle. These
216
Fuchs B. and Ritz T..
Usability for Blended Shopping - Solving Major Flaws by Applying Usability Engineering and Proven Integration Technologies.
DOI: 10.5220/0005113502160223
In Proceedings of the 11th International Conference on e-Business (ICE-B-2014), pages 216-223
ISBN: 978-989-758-043-7
Copyright
c
2014 SCITEPRESS (Science and Technology Publications, Lda.)
process models are summarized under the term
Usability Engineering (Mayhew, 1999). Only with a
deep understanding of the cognitive processes of the
end user the mental thought processes can be
transferred to interactions at the computer. This
guarantees expectation conformity of the user
interface (Norman & Draper S., 1986).
While user interface design addresses mainly the
visual design of the user interface, Usability
Engineering describes both the development of
interactive systems and the design of appropriate
functions and user interactions in a specific use
context. It influences the design surface but is not
limited to it. Besides usability recent software
development increasingly aims to satisfy the
customer when using the newest developments. This
is dedicated to the field of user experience. User
experience describes the perception and reactions
resulting from the actual and / or expected use of an
application (see DIN/ISO 9241-210). This adds a
hedonic component. Experience includes cognitive,
affective, emotional, social and physical responses
from the user regarding the application. Aesthetics,
fun, functionality, enjoyment and personal
development (Hassenzahl, 2004) and brand image
influence the user experience. The developments of
the past show that not only interaction design
domains enjoy user experience as seen by the
success of the Apple iPhone (Koskinen &
Keinonen). At a first glance user experience
influences mainly interaction and interface design,
but also has impact on user documentation, support
and maintenance. In order to meet those
requirements, the user’s strengths, limitations,
preferences and expectations are taken into account
(DIN/ISO 9241-210). Usable systems and products
tend to be more successful in commercial and
technical terms (DIN EN ISO 9241-210). An easy-
to-use system that supports the user in his tasks can
save training cost and can help to reduce support and
service cost.
User-centered or human-centered design was
coined by Donald Norman (Norman & Draper S.,
1986) in the 80s of the last century. This design
philosophy takes the users' needs as a basis from the
start when developing software. It indicates the
procedure to ensure usability in the development of
interactive systems. This is done with the help of
skills and techniques of ergonomics and usability
(DIN EN ISO 9241-210). User-centered design is
based on the idea that a specific solution is not
supposed to satisfy all people in general, but the
specific user. The knowledge about the user enables
the developer and designer to consider usability
aspects and helps to increase the chance that the user
accepts the new development. Following the field of
Blended Shopping is introduced and usability
problems in this area are identified.
3 BLENDED SHOPPING
Until some years ago traditional retail sale was the
distribution channel mostly used for consumer
goods. Then eCommerce became well-stablished
(Laudon & Traver, 2008). When retailers with a
branch network started to enter the digital sales
channel they often organized and offered
eCommerce separated from their branches (see
figure 1).
Blended Shopping is the idea to respond to the
changed shopping behavior of consumers (Hudetz,
2011) by combining all sales and communication
channels to benefit both, retailer and consumer.
Blended Shopping is understood as the “execution of
the transaction phases (information, mediation,
negotiation, contracting, fulfilment and after-sales)
involving both, real sales and presentation
mechanisms as well as network based sales
functionality” (Fuchs & Ritz, 2009a). A couple of
available approaches deal with issues like no-line
commerce (Heinemann, 2013), multichannel or
omnichannel (Institut für Handelsforschung, 2008),
but they focus on different levels of integrating
processes.
Figure 1: Separated channels.
In this paper the definition of the term Blended
Shopping is used with regards to former publication
in this field. Figure 2 illustrates the idea of Blended
Shopping in comparison to the traditional approach
(figure 1).
UsabilityforBlendedShopping-SolvingMajorFlawsbyApplyingUsabilityEngineeringandProvenIntegration
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Figure 2: Blended shopping.
Since 2008 we study the penetration of Blended
Shopping approaches in practice. The first field
study was published in 2009 (Fuchs & Ritz, 2009a).
The field study focused on the integration of
processes as an enabler for Blended Shopping
approaches. As one outcome it revealed that
integrated processes were not established by
merchants in 2008. Since then yearly test purchases
show that this outcome is still valid.
Based upon this first study we analyzed the
linkage (e.g. by QR-Codes) between newspaper ads
or other printed sales material used in branches and
eCommerce (Fuchs & Ritz, 2009b).This second field
study found out that no linkage between printed
sales material and eCommerce (e.g. with the help of
QR-Codes) was offered in 2009, even in cases where
advertiser had an online shop or web site. Latest
updates of the second field study revealed that trade
chains start to employ QR-Codes to link printed
sales ads to products.
Many traditional retailers feel threatened by
eCommerce competition but miss to take advantage
from their position in local shopping environments.
Every single city center merchant competes with
huge internet retailer like Amazon showing one face
to the customer but involves different distance
sellers. To use a joint appearance as a merchant
community mapping the real city center to the
virtual world could strengthen the competitive
position of all local merchants. Those approaches
would fit in the top right rectangle of the matrix
shown in figure 3 (Blended Shopping 2.0). Blended
Shopping 2.0 will be addressed in subsection 5.3.
In general developing Blended Shopping
concepts requires a lot of analytic capabilities and
flexibility of merchants to enter this new field.
Figure 3: Blended Shopping matrix.
Besides this, merchants have to deal with the
problem that no expectation conformity is
established yet. According to ISO 9241-110
expectation conformity is given when a dialog is
consistent and “corresponds to the user's
characteristics, for example his domain knowledge,
his education level and experience as well as the
generally accepted conventions.” (International
Organization for Standardization). This definition
refers to established factors. Blended Shopping is
not offered often by merchants. Consumers don’t
have experience with Blended Shopping and don’t
know what to expect from it. This lack in
expectations leads to a lack in demand which does
not force merchants to satisfy consumer demands.
Based on all research results in the described areas
we identified main usability problems that block the
dissemination of Blended Shopping concepts. Those
are described in the following section.
4 USABILITY PROBLEMS
We identified two dimensions of usability problems
(see figure 4).
1. Users are confused by the Blended Shopping
process. Our research will show that this is a
result of heterogeneous attempts (referred to
as vertical usability problems).
2. Additionally, users are confronted with new
integration technologies like RFID, NFC and
two-dimensional barcodes like QR-Codes.
The research will reveal a lack of user
acceptance (referred to as horizontal usability
problems).
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Figure 4: Usability Problems.
4.1 Vertical Usability Problems
As shown in subsection 3.2 first merchants start to
seize the idea of Blended Shopping and develop own
concepts. As mentioned the attempts are more in an
experimental stage. Thus the results are very
heterogeneous regarding their interaction concepts
and process organization.
Every merchant decides on his own which
process steps are blended. One decides that return of
goods ordered in the webshop is excluded, others
allow it. In the end the consumer never knows what
to expect. Because of this diversity consumers were
not able to establish an expectation towards Blended
Shopping so far. When developing IT solutions and
taking usability into consideration it is important to
know about the users (as explained in section 2) and
their expectations regarding surface and interaction
of an application. Interaction concepts of different
platforms result in a platform-dependent "user
experience" for every user. To achieve a high degree
of expectation conformity usually developer need
access to this user experience. Otherwise
development projects result in applications that work
technically but neither can exploit the potential nor
generate a high degree of recognition.
Users often have a very unique picture and
understanding of what they do and what the system
can do. This phenomenon is reflected in dealing with
everyday things as well as in the use of software
applications. Their mental model may differ from
the actual functionality – e.g. the idea of electricity
as something that flows through the power line is
popular. Even if this is technically not true it does
not hinder the use of electricity. Such ideas are first
"sticky" which means that the information is
difficult to convey (Hippel & Katz, 2002).
Particularly when developing solutions for new
usage scenarios for users with no available
compilation of expectations such as Blended
Shopping, a lot of experience is required. In
subsection 5.1 we will present a methodological
approach which allows:
To derive added value Blended Shopping
scenarios
To derive user profiles to prepare custom
tailored experience
To derive usability requirements
4.2 Horizontal Usability Problems
To address the second problem area we assume that
the strongly growing popularity of smartphones
leads to a mobile use of Blended Shopping
possibilities. That means that we have to deal with
ways to connect "the Internet" to the branch with the
help of mobile phones. There are different
technologies to establish interaction between
customer and merchant (or his products / services),
namely e. G. iBeacons, RFID, (RFID Basis, 2012),
NFC (Gartner Group, 2013), Barcodes, QR-Codes.
While iBeacons, RFID and NFC use wireless
connections (radio frequency) codes operate
optically. The main advantages of optical methods
are that the production costs are very low and that
the necessary applications are already relatively
wide distributed. Mobile tagging with QR-Codes
allows context-sensible linking and is easy to
implement into organizational processes. In the field
studies we found out that two-dimensional codes are
increasingly employed by merchants. In subsection
5.2 we will transfer already available research on the
usability of QR-Codes to Blended Shopping and
enrich the known findings by individual
requirements resulting from Blended Shopping field
of application.
5 SOLUTIONS FOR THE
USABILITY PROBLEMS
After describing the usability problem fields in
section 4 we now suggest approaches to overcome
those problems. Again, we address vertical
(subsection 5.1) and horizontal (subsection 5.2)
problems and describe then an overall approach in
subsection 5.3.
5.1 Integrated Method to Cope with
Vertical Usability Problems
A possible solution for vertical usability problems
described in 4.1 is to apply available approaches
consequently (see figure 5).
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1. Situation and basic conditions of merchant and
product portfolio have to be evaluated as a basis
for the development of appropriate Blended
Shopping concepts. This can be done with the
help of a method presented at WEBIST 2011
(Fuchs & Ritz, 2011) which offers structured
guidance in the field of product information
systems but demands individual assessment of
each situation. Three core factors were
identified:
Customer
Product
Shopping experience.
The factors customer and product are closely
connected. The product influences the
customer’s information demand. Involvement
(Nieschlag, Dichtl, & Hörschgen, 2002) may be
used to distinguish products on the basis of the
consumer’s motivation to select and handle
product-related information. Products with high
involvement like smartphones need another kind
of product information system compared to low
involvement products like shampoo (Kuß &
Tomczak, 2007). Additionally shopping
experience which should be created by the
product information system is emphasized in the
described method. Shopping experience
(Weinberg, 1992) is understood as a subjectively
sensed contribution to the consumer’s quality of
life generated by a product, service, sales
conversation or anything related to the product
presentation. The introduced method allows the
evaluation of the product information system
requirements in a given framework (product,
situation) and supports the development of
realization approaches (e.g. mobile or terminal
solution, shape, necessary features,…).
2. User, use context, conditions like light, weather,
connection to network, etc. have to be
methodically surveyed. The tool supported
requirement analysis (Damm, Ritz, & Strauch,
2010), (Ellerweg & Ritz, 2008) may be
employed to do so. In general the determining
factors when developing mobile solutions have
to be taken into account (Ritz, 2007).
The results of step 1 – reasonable Blended
Shopping use cases with regard to product, merchant
and user characteristics – and step 2 – context
model, with regard to user profile, technical
infrastructure and location characteristics – allow to
derive usability requirements for the pursued
Blended Shopping solution. Then it is possible to
define tasks and appropriate usability goals, assign
measures and thresholds. The usability requirements
aim to serve as guidelines for the developer and later
additionally as acceptance criteria to document
fulfillment.
Figure 5: Integrated method.
5.2 Usability Requirements for
Applying QR-Codes to Cope with
Horizontal Usability Problems
QR-Codes as a bridging technology were described
in subsection 4.2. As explained we assume that a
lack of user acceptance leads to a hesitant use in
practice. Already in our second field study in 2009
we analyzed the process of linking eCommerce to
the printed sales support. In the paper at hand we
transfer the findings with regards to usability from
paper-eCommerce to traditional retail-eCommerce
(Blended Shopping) where it requires a reasonable
and derived style. Usability is an important success
factor for the implementation and dissemination of
mobile tagging. When a 2D-Code for example can’t
be read several times, the user probably will not test
this technology another time.
Possible reasons for failures can be a too small
printed code, a bad cell phone camera and poor
lighting conditions. Depending on the size of the
printed code the angle at which one stands to the
printed QR-Code is important as well as the contrast
ratios and the size of the neutral (white) frame. In
the survey several scenarios of the usability of QR-
Codes in daily routines were tested. As an example
following scenarios are described in which mobile
tagging can come to use. The situations have in
common that
the user’s hands are free (e.g. holding
newspaper)
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the user might consume something alongside
(coffee, breakfast, wine, etc.)
the user has a mobile phone with camera,
internet access and tag reader with him/her.
The selected situations might be different in
light, seat position and position towards the QR-
Code. Figure 6 and 7 show two different situations
of the same use context: the user tries to scan a QR-
Code with different lighting conditions, positions to
the QR-Code, time pressure, etc.
Figure 6: Example usability test A.
Figure 7: Example usability test B.
Figure 6 shows a user sitting at a table for
breakfast. She tries to get the first news of the day
with the newspaper next to the plate or in the hand
while eating. Figure 7 shows a user reading at home
after work, reading the newspaper to relax in an
unhurried way while sitting in an armchair. Here,
lighting, seating position, attitude towards the
newspaper, web access and permitted time for the
scanning process are different and influence the
usability as well as the quality of the printed QR-
Code, sometimes dependent on the quality of
material printed on (e.g. crinkled paper). The
readability and fault tolerance was tested as showed
in figure 8. The picture does not refer to a usual
usage context but is customized for testing.
The test results revealed that QR-Codes with a
white frame – the so called quiet zone – with the size
of 4 mm can be scanned fast. Giving access to the
website via Wi-Fi is efficient with the established
tag reader. Mobile tagging works very reliable. QR
codes without the quiet zone are difficult to scan and
thus unreliable in practice. Mostly it does not work
at the first attempt. Because such a high error rate
would frustrate the user it is necessary to
print QR-Codes always with a quiet zone
print QR-Codes at least at a size of 4x 4 mm
including the quiet zone.
Figure 8: QR-Code tests.
Some tag generators automatically add the quiet
zone, such as at the Tagnition generator. The results
regarding the flexibility of camera angle during the
scanning process (tilting of the camera to the side or
to the front or rear) reveal the trend that QR-Codes
allow the necessary flexibility of up to 40° to the
side and to the front and to the rear (distance
between code and camera about 10-15 cm).Users
should not scan the code slantwise. Since it is not
always possible to influence users it is preferred
when technology forgives mistakes. Even in mobile
UsabilityforBlendedShopping-SolvingMajorFlawsbyApplyingUsabilityEngineeringandProvenIntegration
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scenarios, e.g. when movements or tremors of the
hands prevent a steadiness of the mobile phones,
QR-Codes can be easily scanned. Only the time will
be affected by movements, mistakes do not occur.
There was not a single test situation in which a code
could not be decoded. The same result was recorded
for crinkled paper and minor damages of the code.
The findings of the paper-eCommerce use context
responds to the shop-eCommerce use context as
follows:
In order to offer Blended Shopping, QR-
Codes have to be made accessible for
consumers. The tests regarding readability
and quality requirements can be transferred.
The focus for Blended Shopping scenarios
base upon the idea that mobile devices are
used. The tests regarding flexibility of camera
angle and mobile context are relevant in this
context as well.
Additionally it is necessary to add a further
element. As explained in the paper consumers are
not used to QR-Codes in shops. They don’t know
what to expect. To create expectation conformity it
is necessary to introduce the aim of the code (“here
you get further product-related information”, “here
you can purchase”). Depending on the target group it
might also be necessary to introduce the use process
(“Step 1: introduce a QR-Code reader; Step 2: scan
the QR-Code,…). Novice users have to be put in the
position to take advantage of the offered technology
and get advice how to do so.
Finally requirements resulting from technical
conditions have to be defined and tested (e.g. is it
possible to have access to network in the
underground sales rooms). This is a clear linking
point to the proposed methodological approach in
5.1. In total the comparison of the paper-eCommerce
tests revealed that QR-Codes are a suitable
technology for Blended Shopping concepts (shop-
eCommerce context) with necessary enlargements.
5.3 Blended Shopping 2.0 Approaches
to Address Usability Problems
In subsection 3.2 we assumed that merchants and
consumer could take advantage from Blended
Shopping 2.0 approaches.
Such approaches combine the processes of
traditional retail and eCommerce of a merchant
community, e. G. of a city center (see figure 9).
The overall aim is to motivate consumer to purchase
in their local city center by addressing their needs (e.
G. convenience, shopping experience). An approach
to do so would be to organize the distribution of
shopped goods in the background while the
consumer continues to go shopping in the city
center. Another approach could be to support the
consumer to select matching clothes and make it
easier to take advice from social groups by
establishing a joint dressing zone or an interactive
dressing room. Those approaches need to be
evaluated regarding cost, feasibility, needed
infrastructure, legal and organizational impacts.
Methods to do this in a structured way are currently
developed in our research group.
Figure 9: Blended Shopping 2.0.
In general Blended Shopping 2.0 approaches
could help to solve vertical and horizontal usability
problems. Vertical usability problems can be
overcome when the city center merchants agree on a
kind of standard regarding Blended Shopping
processes. Then consumers know what can be
expected from city center Blended Shopping
(meeting expectation conformity).
Additionally the city center merchants would
have to agree on a standard interaction technology
which could increase the acceptance level.
Cooperating in Blended Shopping 2.0 concepts
could enable merchants to offer outstanding
shopping experiences and services to consumers
which would strengthen the USP of the whole city
center and thus of every single merchant.
6 SUMMARY AND OUTLOOK
The paper started with reminding the potential of
integrating traditional commerce and eCommerce
into integrated Blended Shopping scenarios. Field
studies indicate that there are still usability flaws
which prohibit a wide range of user acceptance.
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Within this paper the usability problems are
categorized in two groups. The first one represent
flaws which result from the fact that the solutions
recently found are more experimental. Thus the user
cannot rely on known interaction patterns and that is
why user expectation is hard to fulfill. The second
group of usability problems could be assigned with
integration technologies to link the physical world
with the virtual one. For the problem category an
integrated methodological approach was presented,
which support reasonable concepts taking user
profiles and special characteristics of the product
into account. For the second category usability
requirements for the usage of QR-Codes are
transferred to Blended Shopping and more precisely
to the usage of a link from the merchant in the city
center to the virtual world. These findings were
amalgamated by individual requirements resulting
from the field of application. Then Blended
Shopping 2.0 is described to jointly address both
problem categories. In future research we will
extend both problem solution attempts. The vertical
problems will be tackled by deriving interaction
patterns for Blended Shopping scenarios which
could be used as building blocks and deliver a de
facto standard in future. Further research for
integration technologies will extend our research to
new technologies like NFC or Bluetooth based
technologies as Beacon. Additionally we focus on
developing an evaluation method for Blended
Shopping 2.0 scenarios.
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