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Aesthetics, Visual Appeal, Usability, and User Satisfaction:
What Do the User’s Eyes Tell the User’s Brain?
Gitte Lindgaard
Human Oriented Technology Lab (HOTLab)
Carleton University, Ottawa, ON K1S 5B6, Canada
Abstract
The impact of colour on the first impression of a website is discussed in the light of
several rather puzzling experimental findings suggesting that background colour and
colour combinations might influence users’ subsequent opinion of, and satisfaction
with, a site. Theories of, and approaches to, studying aesthetics and emotion are
outlined briefly. It is concluded that, although the criteria by which people judge visual
appeal, user satisfaction and trustworthiness are still unclear, perceived usability
appears to be related to the detection of stumbling blocks that hinder smooth
interaction with a web site and probably to the orderliness of screens. User satisfaction
is a complex construct that incorporates several measurable concepts and is the
culmination of the interactive user experience. Experimental results suggest that
people may be more satisfied with a beautiful product that performs sub-optimally than
with a more usable but less appealing product. A glance into the future importance of
the topics discussed is offered.
Keywords: aesthetics, emotion, user satisfaction, first impression, mere exposure
effect
1. Introduction
When visiting an art exhibition, why do people dwell for 30 minutes in front of
one painting and only 10 seconds in front of another? What is it that makes one
experience so compelling - and another barely noticeable, even when two paintings are
of the same genre, painted in the same period, in the same style, and by the same
artist? I stumbled across this question nearly a decade ago after obtaining some rather
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puzzling results in a usability test of a local Government web site (Lindgaard 1999). In
that evaluation one group of participants rated perceived usability and satisfaction after
completing a standard usability test that exposed the worst of the usability problems
identified in the preceding heuristic evaluation. Since participants managed to complete
only one half of the tasks successfully, it is safe to assume that they would be
unimpressed with the site. However, it was puzzling that both satisfaction and
perceived usability ratings were just as low in the control condition in which another
group of participants had merely browsed the site for a short time without performing
any usability tasks or encountering usability problems while browsing the site.
Our research suggests that the relative appeal of visual stimuli is closely related
to both user satisfaction and perceived usability. It also suggests that judgments of
visual appeal and satisfaction may, at least in some contexts, depend heavily on the
first impression of such stimuli and on the emotion they evoke in the user that set the
scene for the entire interactive user experience. This paper explores some of these
relationships in an effort to furnish plausible explanations accounting for curious results
such as those found in abovementioned web site.
Definitions and theories of experimental aesthetics and the link of these to
human emotion are outlined briefly next, followed by a description of research that
appears to underline the immediate, first impressions and reactions to salient visual
stimuli. The difficult problem of studying colour is then touched upon to underscore the
complexity of the relationships among all these concepts. The paper concludes with a
glance into the future importance of understanding the role of visual appeal in shaping
the user experience affecting user satisfaction as well as on human performance.
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2. Definitions and Theories of Aesthetics
Aesthetics is variously defined as beauty in appearance (Lavie & Tractinsky,
2004), visual appeal (Lindgaard & Dudek, 2003), an experience (Ramachandran &
Blakeslee, 1998), an attitude (Cupchik, 1993), a property of objects (Porteous, 1996), a
response or a judgment (Hassenzahl, 2004a; 2004b), and a process (Langer, 1967).
Common to all of these terms is that aesthetics is seen to have something to do with
pleasure and harmony that human beings are capable of experiencing. This wide
variety of definitions testifies to the complexity of the concept, which has not deterred
researchers from working in this still rather nebulous and evasive area.
Early studies in experimental aesthetics led to several theories, the most
comprehensive of which was formulated by Berlyne (1971;1972). Berlyne’s research
showed consistently that moderate complexity was preferred over simple or extremely
complex stimuli. Theoretically, this was interpreted to mean that, beyond a certain level
of complexity, the subject’s arousal level would be located on the downwards slope of
the inverted-U curve that characterizes the arousal function, at a point at which the
experience increased in unpleasantness hand in hand with increasing complexity.
From this work, Berlyne proposed the so-called ‘collative-motivation’ model
according to which aesthetic behaviour was conceived as an elaborate form of
explorative behaviour driven by pleasure-inducing arousal fluctuations. Key
determinants of arousal fluctuation were termed ‘collative variables’, which entailed
either a comparison of stimulus elements (for example, complexity) or aspects of
experience (for example, novelty). One prediction of the model was that intermediate
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levels of arousal would be preferred, leading to the classic inverted U-shaped
complexity-preference function. This prediction was confirmed in numerous studies
using abstract visual patterns such as dots and random polygons as stimuli. However,
when more concrete, real-world stimuli were introduced such as paintings, buildings,
and furniture, the model’s predictive performance was markedly attenuated (Whitfield
2000). In these studies, preferences were characterized by the categories to which the
stimulus belonged. That is, they were based on the degree to which the stimulus
represented the category. A ‘categorical’ model was proposed to account for these
results (Whitfield & Slatter 1979; Whitfield 1983). This model conceived of aesthetics in
terms of information processing demands, whereby stimuli were not processed per se,
but rather judged in the context of the category to which they were assigned. This
same phenomenon is well known in studies of human decision making in which the
‘representativeness bias’ (for example, Kahneman, Slovic & Tversky 1982) features
prominently among an entire family of judgmental biases. Representativeness proved
an effective predictor of preference in studies of aesthetics using real-world stimuli.
An attempt to reconcile the two opposing theories resulted in the bi-polar
‘categorical-motivational’ model (Whitfield 2000) that incorporates both categorical and
motivational drivers. The human-centred goal is the modulation of categories leading to
greater fitness of purpose. In the categorical-motivational model, categories are
assumed to be well formed and closed to further articulation at one end of the
continuum, and ill formed, open to further articulation, at the other. Affect would be
strongest for stimuli representing the well-formed categories that would maximally
conform to expectations. Such stimuli would require minimal processing. At the other
extreme, novel stimuli would result in the strongest affect provided these would contain
sufficient redundancies to permit assignment to a category. Maximum novelty would
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thus be assumed to be non-categorisable and therefore incapable of assimilation. The
underlying assumption is that the value of assimilable stimuli is to elaborate the
category structure thereby providing ‘knowledge’. Novel stimuli would thus have
positive value to the extent that they contribute to internal category elaboration and
differentiation. A thorough discussion of these models may be found in Whitfield (2000)
and in Lindgaard & Whitfield (2004).
Despite this progression in predictive and speculative human response models,
considerable confusion surrounds the concept of aesthetics as alluded to earlier. As
indicated earlier, some researchers regard aesthetics as properties of an object
associated with its “beauty” (Tractinsky, Katz & Ikar 2000), a concept that has been
further refined into what Tractinsky and his colleagues have recently termed “classical
aesthetics” (Lavie & Tractinsky 2004), which is similar to Hassenzahl’s notion of
“goodness” (Hassenzahl 2004), and “expressive” aesthetics, that Hassenzahl calls
“beauty”. However, even the term “beauty” has at least five clearly distinguishable
meanings in philosophy:
In the context of a metaphysical consideration of the world’s order,
beauty is equated with its orderliness [Tractinsky’s “classical
aesthetics” and property of objects]. In the epistemological context
derived from Baumgarten, beauty is thought of as adequacy to the
mind in perception [Hassenzahl’s “goodness”, inside the viewer’s
head]. From the anthropological point of view it may seem to be
nothing more than sensual attractiveness [Berlyne’s work on arousal;
Norman’s (2004) notion of “visceral emotion”]. To the legislators of
taste it tends to become one aesthetic quality variously differentiated
among a number. Those reflecting more generally upon criticism may
use it to mean ‘aesthetic excellence’ [Tractinsky’s “expressive
aesthetics”]: that is, as an almost empty term, standing for a problem
rather than for its solution (Spearshott 1963; p. 59). [comments and
italics added]
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Yet, as acknowledged by Spearshott none of these senses of the term
correspond to its normal usage, being applied “chiefly to women and weather”
(Lindgaard & Whitfield 2001, p. 375). Aesthetics, like beauty, is thus as elusive as it is
confusing. The similarity or overlap between beauty and aesthetics remains undefined;
we are unsure about what is being judged (Frohlich 2004), whether they are properties
of objects in the world, subjective experiences, emotional reactions residing “in the eye
of the beholder”, or cognitive judgments (Hassenzahl 2004a; 2004b; Norman 2004;
Frohlich 2004). Aesthetics therefore lacks an affinity with the main paradigms of
psychological and HCI research, and has no secure theoretical attachment point: it
lacks a home. Yet, even if aesthetics is a property of objects, when confronted with an
object of beauty, it does evoke a positive emotional experience in the viewer.
3. From aesthetics to emotion
To the extent that aesthetics is a pleasant experience or an experience that
leads to pleasure, it implies a relationship to emotion. Without going into details of the
current emotion literature, a valuable review of current emotion theories may be found
in Martin and Clore (2001). For the present purpose of showing the link between
aesthetics and emotion, only Norman’s (2004) recent discussion of emotion is
mentioned here. Norman conceives of emotion in term of three levels of processing.
The subconscious visceral level is perceptual and gives rise to immediate judgments.
Recent research has shown unequivocally that judgments at this level can be made
reliably after a stimulus has been shown for only 50 milliseconds (Lindgaard, Dudek,
Fernandes & Brown, 2006). The finding is important because it suggests that this
immediate judgment is a biologically determined effect (Zajonc, 1980) which occurs at
a subconscious level before the brain has had time to evaluate the stimulus at a
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cognitive level. It is based, as it were, on “what my body tells me to feel” rather than on
“what my brain tells me to think”. This is discussed in more detail in the next section.
Norman’s second level of emotion, the behavioural level, is expectation-driven
and also still subconscious. At that level, a judgment of appeal is thus likely to be
based on a comparison of what the user expects to see, hear, touch, smell, or taste,
and the degree to which the stimulus actually meets this pre-determined expectation.
The third level in Norman’s model is reflective, intellectually-driven. At that level, the
web user encountering a new web site may be focusing on usability problems if the first
impression was negative, and on the enjoyable aspects of the site if the first impression
was positive. Thus, whereas the emotion at the visceral level is holistic and diffuse, the
sum of those initial feelings now combine into an emotion that enables the user to
decide if the web site is great or otherwise. In terms of Whitfield’s (2000) categorical-
motivational model that decision would depend on the degree to which the site would
meet expectations; these are themselves based on the sum of experienced sites of the
same genre and the extent to which that genre is already well-defined and thus closed
to further articulation. It is reasonable to argue that web sites in general have not reach
a level of articulation like, for example, gothic or renaissance churches, and that
therefore users’ internal criteria for judging a site is based on issues other than whether
the site fits a fixed model of similar sites inside their heads.
4. The role of the first impression and its effect on the subsequent Interactive
experience
The above discussion of aesthetics and its effect on emotion leads to thoughts
on the first impression – how quickly it is formed, how long it lingers on, and its effect, if
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any, on other, unrelated activities such as judging the likeability of a fictitious person or
traversing a web site effectively.
To decide just how quickly a first impression is formed, think about what
happens when you first meet a new person. You ‘know’ instantly whether that person
makes you feel comfortable or otherwise. That ‘knowledge’ is not the result of a
rational, considered response; it is indeed the physiological response that Norman
(2004) refers to as the visceral level of emotion. Empirical evidence supporting this
rapid decision making was first provided in the behavioural literature by Zajonc (1980)
who coined the term ‘mere exposure effect’. Typically, Zajonc would show his
experimental participants numerous slides of similar meaningless random dot patterns,
polygons, or Japanese ideograms, for 1-20 msec in the first round. In the second
round, he paired stimuli previously seen with new ones, asking participants which they
preferred. His results showed reliably that people preferred images they had seen
before. In addition, as the number of exposures in the first round increased,
preferences in the second round became more extreme. However, participants had no
recollection whatsoever of having seen any of the images before; apparently, their level
of ‘familiarity’ with the preferred stimuli belonged squarely in the pre-attentive sphere in
which an organism has not yet had a chance to analyse or evaluate the incoming
stimuli. That is, cognition had not had time to register what the participants’ eyes had
seen.
Zajonc’s experiments sparked a lively debate in the literature on whether
‘emotion’ actually precedes ‘cognition’ or vice versa; his findings were subsequently
replicated and confirmed in hundreds of experiments (Bornstein, 1992). About a
decade later, LeDoux (1994;1996), a neurophysiologist, reported findings revealing
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“beyond the shadow of doubt” (Damasio 2000, p. 70; LeDoux 1992) a small bundle of
neurons that lead directly from the hypothalamus to the amygdala across a single
synapse. This contradicts the traditional view that stimuli travelling along the visual
pathway from the retina in the eye via the hypothalamus and the thalamus, to the
occipital cortex where they are interpreted for meaning before sending signals back to
the amygdala in the limbic system that is the ‘seat of emotion’. This more recently
discovered bundle of neurons allows the amygdala to receive direct inputs from the
sensory organs and initiate a response within a few milliseconds, before the neocortex
has interpreted the meaning of the stimuli (LeDoux 1994). Thus the amygdala does not
depend entirely on signals from the neocortex as originally believed, and Zajonc’s early
findings are beginning to converge with more recent theoretical explanations of human
emotion as well as with empirical evidence.
The mere exposure effect begins to wane once the stimulus exposure time
exceeds 50msec, when the organism begins to take more detailed information into
consideration. Therefore, if visual appeal is appraised within that window of 50 msec,
as indeed a series of experiments in our lab showed clearly to be the case (Fernandes,
Lindgaard & Dillon 2003; Lindgaard, Dudek, Fernandes & Brown, 2006), the judgment
involves the amygdala over which the neocortex has no control. The organism’s
response can thus truly be said to be visceral (Norman 2004). This has important
implications for web design and budget resource allocation, because the value of
textual information is likely to be assessed in terms of the site’s immediate visual
appeal. So, an e-commerce web site representing a business that is in competition with
numerous others on the Internet and that fails to meet users’ expectations both in
terms of aesthetics and in terms of its informative content is unlikely to be successful at
converting browsers to customers even if its quality of products or services is superios
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to its competitors. Either people will instantly click on to the next site, or they will
interpret even the slightest usability flaw negatively to confirm their initial emotional
impression. By contrast, a visually appealing site will be forgiven for its minor or even
major usability blemishes because the first impression was positive.
There is thus evidence that findings emerging from neurophysiology is
converging with those contributed from psychology, supporting the claim that emotion
can precede cognition and that, at least in some instances, the decision to like or
dislike an incoming stimulus is based on the interpretation of a visceral response that is
felt rather than thought (Damasio 2000).
5. From experience to user satisfaction
According to some researchers, design is about user experience rather than
about the creation of products (Buxton, 2005). The purpose of physical objects is to
“engage us in an experience – an experience that is largely shaped by affordances and
character embedded in the product itself” (Buxton, 2005, p 47). The term “affordances”,
although used in the sense of Gibsonian (Gibson, 1966) perception meaning “action
possibilities”, it actually refers to “perceived affordances” as identified by Norman
(1988). By “character”, Buxton means the experiential aesthetic value. Buston
discusses his experiences with three different juicers which, although two of these are
very similar in design look-and-feel, give rise to qualitatively different experiences.
Thus, Buxton sees the user experience as the combination of visual as well as
experiential aesthetics and usability – the visceral indicator of the degree of
pleasantness of the experience coupled with the reflective emotional and cognitive
judgment of the product’s utilitarian usability aspects. This example suggests that user
satisfaction is a statement about, or a judgment of, the user experience.
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Let us therefore return to the puzzling user satisfaction data mentioned in the
beginning of this paper in an effort to tease out possible explanations for the results. In
that usability test, none of the subjects knew the Danish county represented by the web
site, the homepage of which is shown in Figure 1 below.
Fig. 1: The homepage of the local Government web site tested
It should be noted that local Government in Denmark is responsible for all social
services including tax collection, registration of citizens for kindergarten, school,
nursing home placement or temporary home nursing requirements, unemployment
benefits and the enforced activation of people who have lost their job, as well as
handling building permits, road repairs, and other those other services offered by local
Governments elsewhere in the world. Every individual is given a unique ID number at
birth that follows her throughout her life, even when moving from one part of the
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country to another. It is therefore reasonable to assume that a Government that knows
virtually everything about its citizens’ lives is not generally regarded with a great deal of
affection.
One possible reason for the results is that the satisfaction ratings reflected
subjects’ attitude towards their country’s local Government rather than being the result
of their interaction with the particular web site. If, however, subjects were actually
judging the site, then Whitfield’s (2000) categorical-motivational model may account for
the findings in the sense that, while subjects’ attitude towards local Government may
be very clear and not necessarily positive, the same would not be true of their
expectations towards Government websites in general. A cursory inspection of a
sample of 50 Danish and 50 Canadian local Government sites showed that there were
no recognizable commonalities between them in the look and feel, the design
principles adhered to, the site architecture, or navigation paths. The local Government
website category is thus quite unformed and still open to further articulation.
Another possible reason is that the first impression was negative, leading test
users to look selectively for negative information to support that first impression.
Background colour is a very salient feature of a web site especially a site that is not
very ‘busy’ looking. It is possible that the very strong and lingering perceptual after-
effect that participants reliably experienced after viewing the bright yellow and blue
homepage for even a brief period of time was unpleasant.
This is especially true when it occurs unexpectedly, possibly rendering the
browsing experience slightly unpleasant also and hence lowering satisfaction and
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perceived usability scores. Especially the yellow colour was considerably brighter and
more saturated on the original site than in the reproduction shown in Figure 1.
However, the reader may still experience a mild perceptual after-effect by fixating on
the black dot near the centre of the page for two minutes, then look away, preferably
onto a white wall. The blue and yellow areas in the Figure will now be reversed. In
particular, the blue area will appear brightly yellow.
Colour is a very salient stimulus, which is known to affect the visual appeal of
web sites (Knutson 1998); when opening a site the background colours are usually
displayed well before the content appears. The literature on human memory, from
social psychology, and from attribution theory, accords with the research on first
impressions discussed earlier. First impressions are very powerful; they often outweigh
subsequent incoming stimuli – thus, primacy effects prevail! Likewise, borrowing from
the human judgment and decision-making literature, we also know that, once people
have made up their mind about something, they tend to search selectively for
information that confirms their hypothesis, falling prey to the so-called confirmation bias
(Mynatt, Doherty & Tweeney 1977) whereby disconfirmatory information is ignored. It
follows that an unpleasant first impression will encourage the viewer to focus on
information affecting their experience negatively, perhaps in the form of usability
problems. Conversely, if the first impression is positive, they are likely to be far more
tolerant of the same usability problems. Given the presence of a strong perceptual
after-effect in the abovementioned web site, one may therefore legitimately question
the impact of background colours on both the first impression and the overall
interactive user experience. That is discussed next.
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5.1 The impact of colour on the interactive experience
Early studies in the psychology of art found that two very bright and highly
saturated primary colours juxtaposed in a painting create what the researchers referred
to as “maximum tension” in the viewer (Kreitler & Kreitler 1972). The abovementioned
blue/yellow web site fulfilled this criterion. Unfortunately, it is unclear what exactly
Kreitler and Kreitler meant by “maximum tension” but one may speculate that it refers
to “interestingness” in the sense defined by Berlyne (1971;1972) in his studies of
arousal mentioned earlier.
The background colour of a web site is usually displayed for several seconds
before additional information appears. Following Zajonc’s (1980) work on the mere
exposure effect discussed earlier and our own work showing that users form an opinion
on the visual appeal of homepages after an exposure time of only 50 milliseconds
(Lindgaard et al., 2006), there should be ample time for the user to detect the stimulus
and decide whether to like or dislike it well before the information contained on the
homepage is even displayed. The first few anecdotal studies in our program therefore
focused on the importance of colour in an attempt to begin to explore the connection
between visual appeal, perceived usability, and user satisfaction with web sites.
Because these studies have been reported elsewhere (Lindgaard 1999), they are only
summarized briefly here.
In an informal preliminary experiment, a group of 90 computer science / HCI
students were first asked to nominate their most and least favoured website and to
explain their choices. Almost without exception, students cited colour as the main
reason for disliking a web site, whereas content was the reason stated for favouring a
site, even when they were equally interested in the content of all selected sites. To
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assess colour preferences, the students were then given a list of 27 randomly selected
organizations such as retail outlets, service providers, and professional societies and
asked to name the background colour and shade (pastel, medium, dark) they
considered most and least appropriate for each site. Qualitative issues such as
brightness and saturation were not mentioned. The results showed clearly that white
and blue were considered most appropriate, that yellow and black were seen as being
least appropriate and that pastel shadings were deemed most- and dark shadings least
appropriate across all the 27 organizations. Clearly, the bright, saturated yellow colour
which dominated the abovementioned web site did not fare well in this assessment.
Thus, a dislike for the actual colours used may also account for the low satisfaction
ratings obtained in the local Government experiment.
Studying colour is very tricky: it is difficult to measure wavelengths accurately;
colours change under different lighting conditions; controlling for brightness and
saturation is almost impossible, and one has no control over the appearance of colour
on a computer monitor. Furthermore, we know little about perceptual colour constancy
across people and across different age groups, in part because our colour vocabulary
is quite impoverished making it impossible to describe colour nuances accurately and
in part because there are sizeable individual differences in colour preferences. Still,
colour is a salient stimulus, and we are pursuing the issue, investigating the extent to
which colour may influence subsequent judgments in a series of current experiments.
In these, colour combinations judged independently to vary in pleasantness are used to
prime participants in one condition in which the task is to judge the likeability of a
number of persons described in short vignettes. The vignettes contain strong positive
and negative personality traits that are manipulated systematically in a factorial
manner. One would expect the least liked colours to yield lower likeability ratings than
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the same vignettes judged in the control condition without colour priming, assuming, of
course, that this negative effect outlasts the stimulus display. It is clearly not possible
as yet unequivocally to determine the impact of colour on the interactive experience.
6. The link between perceived usability and user satisfaction
A pleasant experience such as viewing or navigating a ‘beautiful’ web site has
been shown in several studies to be intrinsically connected to user satisfaction (Buxton,
2005; Lindgaard & Dudek 2002; 2003; Tractinsky & Zmiri 2006). However, in the ISO
9241-11 Standard (ISO 1997) ‘user satisfaction’ is referred to in terms of ‘attitude’ and
‘degree of comfort’ and measured by a number on a 7- or 10-point scale. None of these
terms capture the user experience which, one may argue, culminates in higher or lower
satisfaction. Traditional satisfaction measures also fail to point to particular user
interface issues that could help the web designer understand how to improve her
design. In order to achieve this, it is necessary to identify the factors that contribute to
user satisfaction; this could shed light on the reason(s) for the low satisfaction ratings
obtained in the local Government experiment described earlier. A series of experiments
aiming to learn more about the components of user satisfaction was therefore
performed in our lab. The paradigm was similar to that employed in the control group in
the local Government experiment. Participants were asked to browse a web site for 10
minutes, encouraged to verbalize their experience as they went as well as being
interviewed and rating a set of interaction-related statements at the end of the 10
minutes. Thereafter, they were either excused or asked to complete a usability test on
the same site; they were then interviewed again at the end of the usability test and
asked to respond to the same statements as before. The audio taped sessions enabled
us to collect roughly 3,500 experience-related spontaneous statements that were then
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sorted into five categories, namely aesthetics, emotion, likeability, expectation, and
usability.
Our operational definitions of these five concepts were adequate for sorting
participants’ statements unambiguously, but some of them shared similarities that
made us suspect they would not stand up to more detailed scrutiny. The notion, for
example, of likeability is probably a consequence of visual appeal: if it is pretty, I like it,
if not I don’t. Another series of experiments was therefore performed, aiming to derive
and validate a user satisfaction scale that would point a web designer to issues that, if
modified, could improve the interactive experience with their product. This work is
currently being written up for publication.
Among the web sites used in all of these experiments, one stood out as being
exceedingly beautiful and also completely unusable, as confirmed in the usability test
(Lindgaard & Dudek 2002). The results showed that, even before attempting to
complete the usability tasks, participants knew very well that the site was not usable,
but this did not detract from its high visual appeal. After the usability test, negative
usability-related statements increased considerably, and judgments of perceived
usability were even lower than before the test. Judgments of visual appeal, however,
remained as high in the second- as in the first half of the experiment. A similar finding
was recently reported in a study involving four MP3 player skins in which one that was
reasonably low in usability but very appealing was preferred over another that scored
higher on usability but lower on aesthetics (Mahlke 2006). Findings such as these
suggest that perceived usability and visual appeal are judged independently of one
another, a finding that contradicts some researchers’ claim that “what is beautiful is
[perceived to be] usable” (Tractinsky, Katz & Ikar 2000). This independence of visual
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appeal and perceived usability was again confirmed in a more recent experiment in
which participants rated perceived usability, visual appeal, and trustworthiness of a set
of homepages. The results of that experiment, which is currently being written up for
publication, suggest that individuals’ internal criteria for judging trust and usability are
stable, but that the judgmental criteria differ between people. That is, each person’s
ratings of all three, usability, trust, and visual appeal, were highly reliable from one
occasion to the next, but the criteria on which their judgments relied differed
considerably from one person to the next.
Interestingly, the concept that Tractinsky now calls ‘classical aesthetics’ mostly
refers to elements that are contained in both information design (Zwaga & Easterby
1984) and in screen design principles (for example, Galitz 1981; 1993). Adherence to
these principles helps the user to detect, perceive, and interpret a particular stimulus
as well as to act on it correctly. Basic principles borrowed from human perception are
applied such as grouping items that belong together and separating groups that differ
semantically from others, to lend the resulting screens an ordered impression that is
consistent with users’ expectations. If we accept that this orderliness is visually
appealing and that it contributes to usability, then we are forced to accept Tractinsky et
al.’s (2000) contention that what is beautiful may be usable. This argument again
highlights the lack of an agreed-upon definition of aesthetics or even of usability for that
matter. Buxton (2005) is probably right: the quality of the user experience is a
combination of the perceived affordances and usability factors. The intensity, positive
or negative, of the first impression is likely to set the scene for the amount of attention
subsequently paid to experiential usability and pleasure-of-usage factors, which then
culminate in that judgment of the experience that we might call user satisfaction.
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Despite the fact that findings so far shed no light on the actual criteria by which people
judge visual appeal or user satisfaction and trustworthiness, we can say that perceived
usability is related to the detection of stumbling blocks that hinder smooth interaction
with a web site and probably to the orderliness of screens. User satisfaction is a
complex construct that incorporates several measurable concepts and is the
culmination of the interactive user experience. People are sensitive to perceived
usability problems but these have no impact on the visual appeal, and that apparently,
visual appeal weighs more heavily in preference judgments than usability. It follows
that people may be more satisfied with a beautiful product that performs sub-optimally
than with a more usable but less appealing product.
7. Summary and conclusive remarks
We began by asking why people at an art exhibition tend to dwell very long
before one painting and barely notice another. We then argued that aesthetics,
although still subject to ambiguity in definition, plays a major role in determining how
we feel about a given stimulus, and that a feeling is generated immediately upon
detection of the stimulus. The first impression may or may not be modified with
increasing usage of a product, and ultimately, we argued that user satisfaction is a
judgment about the interactive experience with products including web sites.
Where does this take us and why should we care? One obvious advantage is
the unpacking of the concept of user satisfaction. Traditionally, it has been measured
by a single statement on some rating scale. For the product or web designer, a
satisfaction rating of, say 58.5% does not help to decide how or where the site should
be improved to increase the rating to whatever the preset usability goal demands. The
sheer understanding that satisfaction involves more than utilitarian usability
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considerations in the head of the user is beneficial. Apparently, both the first
impression and the pleasure associated with continued usage are at least as important
as usability concerns. Thus, more effective resource allocation in web design,
especially in e-commerce web design, is one positive and immediate outcome of that
understanding.
Much of the research discussed in this paper suggests that the dichotomy
between emotion and cognition is much less pronounced than traditional cognitive
psychology would have us believe. If indeed the interpretation of our own physiological
signals largely directs our selective search for further information, this suggests that
emotion may play an important role in human performance that goes well beyond web
design. One may speculate that interactive technology that “feels good” or “feels right”
will put the user at ease, or as Czickzenmihaley (2000) would say, the user would be
“in flow” by balancing their knowledge, task skills, and task demands with the design of
the technology intended to support the user’s tasks. The result of this harmony is that
the user feels in control even while executing very complex, cognitively taxing tasks.
The flow state would maximize the amount of cognitive resources available to focus on
the task. Consequently, the extent to which the technology draws negative attention to
itself, it reduces those cognitive resources, which could lead to inferior user
performance. In today’s world, knowledge workers are increasingly at liberty to define,
evolve, and re-define their tasks, jobs, and roles. Interactive technology that supports
and adapts to both the cognitive and the more emotion-based user requirements will
assume increasing importance in the future workplace.
Page21
Acknowledgements
The author would like to thank all who participated in the experiments reported
in this paper. This work was partially supported by NSERC (National Science &
Engineering Research Council)/Cognos, Grant IRCPJ 234088-05.
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