Time stability of user perception of website aesthetics Dustin Witte1, Gerrit Hirschfeld2, Meinald T. Thielsch1 1Institut für Psychologie, Westfälische Wilhelms-Universität Münster, 2Fakultät Wirtschafts- und Sozialwissenschaften, Hochschule Osnabrück Content, usability and aesthetics are important constructs that influence a user's evaluation of websites, but there is a lack of research in examining stability over several days. In this online study, time stability of perceived aesthetics (measured by the Visual Aesthetics of Websites Inventory) was explored over two weeks. Participants (N = 212) evaluated one of eight websites from different content categories three times in a two week period. A high time stability was found for the overall scores as well as all subscales (simplicity, diversity, colorfulness and craftsmanship). Relevance & Research Question Aesthetics is besides content and usability the most important construct which determines a user's evaluation of a website. Website aesthetics is defined as "an immediate pleasurable subjective experience that is directed toward an object and not mediated by intervening reasoning" (Moshagen & Thielsch, 2010, p. 690). Amongst others Leder, Oeberst and Augustin (2004) revealed that aesthetics is processed fast and implicit at first sight and particularly contribute to the global first impression rating of a website. However, no study has been conducted yet that examines the time stability of aesthetics ratings over several days. By gaining further insights in the perception of website aesthetics, our online study aims to close this gap. Participants & Stimuli The VisAWI (Moshagen & Thielsch, 2010) is based on a factor analysis approach and the extracted factors were examined by computing a confirmatory factor analysis. The factors are labeled simplicity, diversity, colorfulness and craftsmanship. Simplicity and diversity each consists of five items, colorfulness and craftsmanship each of four. Convergent, divergent, discriminative, concurrent and experimental validity just as reliability of the instrument could be demonstrated. Cronbach's alpha in the current studie is .92 for the general factor, .91 for simplicity, .89 for diversity, .89 for colorfulness and .86 for craftsmanship. Answers were rated on a 7-point Likert-scale ranging from 1 ("strongly disagree") to 7 ("strongly agree"). A total of 212 participants completed the survey, 126 (59%) of them were female. The age ranged from 16 to 70 years (M= 46.82, sd=14.4) and they had been using the Internet on average 15 years (sd= 4.5). Of all participants, 65 percent held a high school diploma (German Abitur) or a higher degree. The participants were acquainted via the German online panel "PsyWeb" (https://psyweb.uni-muenster.de/) by receiving an invitation for each data point via e-mail. To cover a broad range of different website categories (Thielsch, 2008) eight websites were chosen as stimulus material. They can be assigned to the categories: e-commerce, search engine, corporate website, e-recruiting, download, e-learning, information site and information mocksite. The websites were chosen under the guiding principle of prototypically and should ideally not be known by the participants before. Process Each participants rated only one (the same) website at each time point. At data point T1, the participants provided demographical information and exclusion criteria (e.g. color blindness) were measured. At each data point, the items were presented in a randomized order while the full functional website was presented in the lower half of the screen. Visual Aesthetics of Websites Inventory (VisAWI) The time difference between T1 and T2 was on average 1.5 days, between T2 and T3 12 days and thus 13.5 days between T1 and T3. Results High correlations between the time points were found for the overall scores (.88 - .91) as well as for the aesthetics subscales (.77 - .86). As we found no mean differences in the website evaluations over time (T1-T2, p = .69; T2-T3, p = .97. T1-T3, p = .67), these correlations can be interpreted as an evidence for time stability of perceived website aesthetics. Note. N = 212 per time point; * p < .05; ** p < .01; *** p < .001 1.5 Days 12 Days 13.5 Days VisAWI .89*** .91*** .88*** - Simplicity .86*** .84*** .83*** - Diversity .81*** .82*** - Colorfulness .85*** .77*** - Craftsmanship .78*** Limitations & Further Research The total sample size (N = 212 ) is sufficient, but the group-size per website ranges from 16 (information site) to 41 (information mocksite) participants. Statistics based on such a small sample size should be handled with care. In addition, only one website per category was included in this study. To calculate valid comparisons of website categories, more websites per category and a sufficient sample size per website were needed. Even tough, the VisAWI is a well designed questionnaire, a replication with other questionnaires to make sure that time stability is not unique to the questionnaires is required. Added Value While the importance of aesthetics for first impressions is well proven we found additional evidence for the stability of aesthetics evaluation over short and medium periods. Especially the overall score yielded high retest correlation coefficients. This points clearly to the importance of aesthetics in applied and market research and the suitability of a measurement instrument such as the VisAWI. References Leder, H., Belke, B., Oeberst, A. and Augustin, D. (2004) A model of aesthetic appreciation and aesthetic judgements. Br. J. Psychology, 95, 489-508. Moshagen, M. & Thielsch, M. T. (2010). Facets of visual aesthetics. Human-Computer studies, 68, 689-709. doi:10.1016/j.ijhcs.2010.05.006 Thielsch, M. T. (2008). Ästhetik von Websites. Wahrnehmung von Ästhetik und deren Beziehung zu Inhalt, Usability und Persönlichkeitsmerkmalen. Münster: MV Wissenschaft.   Contact Dustin Witte : dustinwitte@web.de Gerrit Hirschfeld: Hirschfeld@wi.hs-osnabrueck.de Meinald T. Thielsch: thielsch@uni-muenster.de www.meinald.de www.uni-muenster.de/OWMS