IJCSNS International Journal of Computer Science and Network Security, VOL.8 No.11, November 2008 215 Manuscript received November 5, 2008 Manuscript revised November 20, 2008 A Case Study to Identify Quality Attributes Relationships for Web- based Applications Hazura Zulzalil, Abdul Azim Abd Ghani, Mohd Hasan Selamat, Ramlan Mahmod * Department of Information Systems, Department of Multimedia * Faculty of Computer Science and Information Technology University Putra Malaysia, 43400 Serdang, Selangor Darul Ehsan, Malaysia Summary Software quality is a complex concept containing a large number of quality criteria. These quality criteria are usually interactive where preference outcome of one criterion over another criterion is always influenced by the remaining criteria. However, to avoid complexity researchers always tend to construct independent criteria which causing some bias effect in evaluation. This paper presents a method to investigate and identify the relationships of quality criteria in the development of web-based applications (WBA). Experienced-based approach and an online survey were conducted to gather the intended relationships. The results have shown that there exist relationships and interaction between the quality attributes. These relationships will be used later on in the aggregation procedure for the evaluation of the WBA. Keywords: Quality attributes, quality attributes relationships, Web-based Applications, aggregation. 1. Introduction The evaluation of the Web-Based application (WBA) is a complex process since it consists of multiple criteria or attributes to be measured. Researchers have developed software quality models ([1], [2], [3]) that were intended to be comprehensive and applicable to all software development. One of the difficulties with earlier models was the inability to account for dependency among the quality criterion. Since the influence of individual quality criteria is not always independent, individual or groups of quality criterion can influence the overall quality in conflicting ways [4]. This paper presents a method to explore the problem of interacting quality attributes in the development of web- based applications (WBA). The relationships among the quality attributes were derived by experience-based approach. An online survey was conducted to identify the relationships among the quality attributes. The rest of the paper is organized as follows. Section 2 presents the quality characteristics definitions and its relationships. Then, the survey design, covering research question, assumptions and hypotheses, strategy and method, and sample are introduced in the section 3. The last two sections describe the results, conclusion and the future work. 2. Quality Characteristics for WBA Quality model generally define software product qualities as a hierarchy of factors, criteria and metrics. A quality factor represents behavioural characteristics of the system and a quality criterion is an attribute of a quality factor that is related to software production and design, while a quality metrics is a measure that captures some aspect of a quality criterion. The anticipated quality characteristics used in our study are described in Table 1 along with their definitions, which are referring to the evaluation of web-based application. The quality characteristics are adopted from ISO/IEC 9126 standards. The definitions and the choice of indicators are based on a set of Web usability guidelines ([5], [6]) and W3C standards [7]. Table1. Definition of quality characteristics Name Description Functionality The capability of the Web site to provide functions and properties which meet stated and implied needs when the site is used under specified conditions Usability The capability of the Web site to be understood, learned and liked by the user, when used under specified conditions