M. Kurosu (Ed.): Human-Computer Interaction, Part I, HCII 2013, LNCS 8004, pp. 575–584, 2013. © Springer-Verlag Berlin Heidelberg 2013 Ease of Icon Processing Can Predict Icon Appeal Siné McDougall 1 and Irene Reppa 2 1 Bournemouth University, UK 2 Swansea University, UK smcdougall@bournemouth.ac.uk, i.reppa@swansea.ac.uk Abstract. Correlations between subjective ratings of interface usability and ap- peal have been frequently reported. This study examined the possibility that the relationship between usability and appeal are underpinned by implicit percep- tions of ease of processing which act as a heuristic in making judgments of appeal. Ease of processing was manipulated by varying the amount of expe- rience participants gained with icons in a search task prior to judging appeal, as well as varying the familiarity and visual complexity of the icons presented. These manipulations systematically affected response times in the search task (an objective measure of usability). The effects observed in appeal judgments followed the same pattern as for search times, demonstrating that ease of processing predicts judgments of appeal. This suggests that our understanding of interface appeal needs to be predicated on an appreciation of the factors affecting the ease with which information on an interface is processed. Keywords: Interface appeal; usability; processing fluency; icons. 1 Introduction 1.1 The Relationship between Usability and Appeal Interface usability typically refers to the ease with which an interface can be learned and how swiftly and accurately it can be used [1,2]. It is now recognized that enhanc- ing the aesthetic appeal of an interface may be just as important as improving its usa- bility [3]. Recent research has therefore often focused on how interface appeal can be enhanced [4-8]. A number of studies have observed a relationship between ratings of perceived usability and ratings of aesthetic appeal. These studies have typically obtained rat- ings of usability and ratings of appeal for interfaces such as websites, MP3 players, or mobile phones and analyzed the correlation between ratings [9-11]. In a recent re- view Hassenzahl & Monk [12] found that correlations between ratings of usability and appeal are commonly reported and that the strength of the correlation varied in accordance with the context, the nature of the interface, and the task demands. 1.2 Using Ease of Processing as a Heuristic to Judge Appeal The relationship between usability and appeal may be explained by ease of processing accounts of aesthetic appeal. The ease of processing of a stimulus has been suggested