A. Stefani, M. Xenos, “A model for assessing the quality of e-commerce systems” Proceedings of the PC-HCI 2001 Conference on Human Computer Interaction, Patras, pp. 105-109, 2001. 1 A model for assessing the quality of e-commerce systems Antonia Stefani Patras University Department of Mathematics Patras, Rio, GR 26500 stefani4@otenet.gr Michalis Xenos Hellenic Open University School of Science and Technology 16 Sachtouri Str, Patras, GR 26223, Greece xenos@eap.gr SUMMARY This paper presents a model used for assessing the qual- ity of e-commerce systems. The proposed model is used for the analysis of user-centered quality characteristics of e-commerce systems and has formed the basis for the creation of expert evaluation checklists and surveys on user perceived quality of e-commerce systems. The paper discusses quality assessment of e-commerce systems, following the ISO 9126 quality factors and emphasising on the user-centered factors of functionality, usability, reliability and efficiency. The paper presents the decom- position of each of the aforementioned factors in specific characteristics of e-commerce systems, which leads to a hierarchical quality model comprising of three levels. The application of the model is also discussed in brief. KEYWORDS: E-Commerce, Quality, ISO 9126, Func- tionality, Usability, Reliability, Efficiency. INTRODUCTION Electronic commerce (e-commerce) involves sharing business information, maintaining business relationships and conducting business transactions by means of tele- communication networks [1]. The medium of e- commerce is the World Wide Web, which growth has been unprecedented, with millions of users world-wide [2]. Consumers can use the web [3] to purchase all kinds of goods and services, like: books, cars, flowers, food, banking, entertainment, etc. It is easy to understand that e-commerce has brought a whole new range of services to all these users. For this reason, its growth has been impressively rapid. By the year 2003, the number of people purchasing goods and services on-line will have trebled, compared to nowadays, while it is expected that 80% of European companies will be connected to the web [4], meaning that they will be enabled to conduct electronic transactions. E-commerce consists of two dis- tinct categories [5]: Business-to-Consumer (B2C) com- merce and Business-to-Business (B2B) commerce. It should be noted that this work focuses on B2C e- commerce systems, since the proposed model assesses the quality of e-commerce systems, as perceived by end users. As stated by Zwass [6], the principal technologies, which are enabling e-commerce, are computer networking and telecommunications, client-server computing, multimedia and hypermedia. It can be said that e-commerce is a sys- tem which final scope is the satisfaction of the end user. The latter communicates with the virtual seller of the e- commerce shop, using a human-computer interface (HCI). Such interface is user-centred and should be ef- fective for the user [7]. Since the e-commerce user inter- acts with a computer, the quality of the interface should follow the same principles as software quality. In brief, the quality of e-commerce systems is related to system quality, quality of the HCI and quality of the services of- fered. Given the fact that all interaction with the end user is accomplished through the human-computer interface, the quality of e-commerce systems can be addressed in similar terms as software quality. According to the ISO 9126 standard [8], software quality consists of six quality factors, which are functionality, reliability, usability, efficiency, maintainability and port- ability. These factors can be further analysed in specific characteristics. Similar works concerning e-commerce systems, quite often, consider the quality factor of us- ability as the most significant factor of software quality [9]. However, usability is not the only factor involved in e-commerce quality; the quality factors of functionality, reliability and efficiency also contribute to user satisfac- tion. The following section presents the relation of the afore- mentioned quality factors (functionality, reliability, us- ability and efficiency) to the characteristics of e- commerce systems. Emphasis is given on the effort to provide good justification why the specific quality fac- tors play such an important role in user satisfaction. Moreover, the correlation among each of the four quality factors and the e-commerce system characteristics is dis- cussed. The third section presents a model for assessing the quality of e-commerce systems. The model consists