Aesthetic appeal versus usability: Implications for user satisfaction Gitte Lindgaard & Cathy Dudek Carleton HOTLab Ottawa, Canada

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3 Satisfaction …is the poor cousin of usability Satisfaction defined as attitudinal –Avoid negative feelings –Measured in rating scales –Outcomes, summaries We are interested in the experiential –Process –Construct

4 One site tested was very high in appeal and very low in usability Appeal = reliable ‘wow’ effect Usability: Heuristic evaluation found 157 unique problems 121 of these were severe A subset of these were exposed in the 8 usability tasks

5 Research question Does the first impression persist after completing usability tasks? Or do users change their mind after encountering serious usability problems?

6 Measures Satisfaction: proportion of positive statements in –Perceived usability –Perceived aesthetics –emotion –likeability –expectation (Lindgaard & Dudek, 2001)

7 Issues raised here Task demands –Do users who anticipate a usability test pay more attention to usability problems when first browsing a site than users who do not expect a test? –If so, perceived usability scores will be lower for the former than for the latter

8 Experimental design

9 Findings Subjects completed, on average, 3.8 of 8 tasks successfully no subject completed all the tasks no task was completed by all subjects So, it is safe to conclude that usability levels were very low

10 Findings: perceived usability 33% 31%13% Site was not perceived as usable by either group Site was seen to be less usable after than before the test

11 Findings: perceived aesthetics 91% 87%91% Site was perceived as beautiful by both groups Site remained beautiful after the usability test

12 Findings: emotion 87% 66%20% The ratio of positive:negative emotion statements was lower for the test group both before and after the test.

13 Findings: likeability 79% 49%25% The ratio of positive:negative likeability statements was Lower for the test group both before and after the test

14 Findoings: expectation 64% 11%5% The ratio of positive:negative expectation statements was Very much lower for the test group before and after The test

15 Findings: satisfaction 66% 51%25% Satisfaction appears to be determined by several factors

16 The first impression apparently rests on aesthetics The perception of beauty persists, but Perceived usability, likeability and expectation change after facing serious usability problems First Impressions

17 First impression Formed in an instant (3-5 msec) Based on changes in arousal levels (Berlyne, 1971; 1972) Evoked via the amygdala, not via the hypothalamus (Damasio, 2000; LeDoux, 1994;1996; Goleman, 1996) Can be overridden by pre-exposure decision (Epstein, 1997) Is difficult to change – confirmation bias (Doherty, Mynatt & Tweney, 1977)

18 One question is… Does emotion precede cognition… (Zajonc, 1980; Bornstein, 1992) …or is it the other way around? (Epstein, 1997) I.e. are first impressions ‘what my body tells me to feel’, or are they ‘what my brain tells me to think’?

19 Issues raised here Confirmation bias –If the first impression drives satisfaction, it should not change after usability test –If usability drives satisfaction, it should change after usability test –and it should vary between high- and low- usability sites

20 Experimental design Group 1 (n = 40): Browse  interview/ratings Group 2 (n = 40): Browse  interview/ratings  usability test  interview/ratings 2 e-commerce sites tested Scores: (a) proportion of positive statements (b) WAMMI (Kirakowski et al. 1998)

21 Results: Satisfaction Mean satisfaction scores before & after test Main effect, before/after (p <.001); main effect for web site (p,<.05)

22 Perceived usability Mean perceived usability before/after test Main effect before/after (p <.001); main effect for web site (p <.001)

23 Aesthetics Mean aesthetics score before/after test No significant effects

24 Satisfaction, before test only Mean satisfaction scores, first interview Main effect for web site (p <.05); main effect for subject-group (p <.05)

25 Perceived usability before test Mean perceived usability scores before test only Main effect for web site (p <.001)

26 Conclusion Confirmation bias –Aesthetics scores taken on their own did not differ before the test –..and they did not change after test –Confirmation bias on the aesthetics dimension But –Satisfaction scores decreased after the test –Perceived usability scores decreased –No confirmation bias on overall satisfaction or on usability

27 Conclusion Task demands –Lower satisfaction scores for subjects expecting a usability test than for browsing-only subjects suggest that task demands do affect attention to usability –Subjects are sensitive to actual usability levels –As evidenced both in satisfaction scores and in perceived usability scores

28 Conclusion So, satisfaction appears to be driven partly by actual usability Aesthetics judgments appear to be independent of perceived usability

29 Next steps Currently developing satisfaction scales that enable developers to pinpoint where to improve their sites to increase user satisfaction

30 So, now to aesthetics Gary Fernandes MA thesis: –125 sites collected, all of unknown companies –Preliminary study, n = 22 –Selected 25 best and 25 worst sites –N = 30 –Viewed sites for 500 msec, then rated visual appeal in two rounds

31 Measurement scale Very Unattractive Very Attractive

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38 Appeal ratings, study 1

39 Appeal ratings, study 2

40 Visual appeal ratings, study 1 vs study 2

41 Conclusion Aesthetics judgments are made very quickly They are highly robust New results show that they persist even when subjects are able to inspect the home page for an unlimited period of time

42 Next steps Expose stimuli for 40 msec Collect genres of sites Evolve tool enabling companies to test their own web site against others

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