Abstract
Usability is an acknowledged important aspect of any system or product design. Many times it is related to not only product features, but also ultimately profit that can be generated from the product. Good interface design promotes higher mutuality (feeling similar and connected), which in turn leads to higher levels of involvement and a favorable impression of credibility. Many practitioners and researchers (such as Jakob Nielsen, 2000) have elaborated on usability aspects, but few have agreed upon a unifying definition. In 1998 the International Organization for Standardization (ISO) defined usability as the “Extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a specified context of use” (ISO 9241-11, 1998, p. 2). From this definition it can be construed that effectiveness, efficiency, and satisfaction are three pillars for usability measures. In this regard, the ISO defines: • Effectiveness as the “accuracy and completeness with which users achieve specified goals,” • Efficiency as the “resources expended in relation to the accuracy and completeness with which users achieve goals,” and • Satisfaction as the “freedom from discomfort, and positive attitudes towards the use of the product.” The ISO standard acknowledges that the level of usability depends highly on the intended context of use (e.g., users, hardware, software, and social environments). Researchers have demonstrated that the three ISO usability components are distinct. Frøkjær, Hertzum, and Hornbæk (2000) found only a weak relationship among the three usability components. Walker, Fromer, Di Fabbrizio, Mestel, and Hindle (1998) found that efficiency did not translate into user satisfaction. These empirical studies suggest that efficiency, effectiveness, and satisfaction may be independent aspects of usability and a causal relationship among them may be weak or even nonexistent.
TopUsability Standardization
Usability is an acknowledged important aspect of any system or product design. Many times it is related to not only product features, but also ultimately profit that can be generated from the product. Good interface design promotes higher mutuality (feeling similar and connected), which in turn leads to higher levels of involvement and a favorable impression of credibility.
Many practitioners and researchers (such as Jakob Nielsen, 2000) have elaborated on usability aspects, but few have agreed upon a unifying definition. In 1998 the International Organization for Standardization (ISO) defined usability as the “Extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a specified context of use” (ISO 9241-11, 1998, p. 2). From this definition it can be construed that effectiveness, efficiency, and satisfaction are three pillars for usability measures. In this regard, the ISO defines:
- •
Effectiveness as the “accuracy and completeness with which users achieve specified goals,”
- •
Efficiency as the “resources expended in relation to the accuracy and completeness with which users achieve goals,” and
- •
Satisfaction as the “freedom from discomfort, and positive attitudes towards the use of the product.”
The ISO standard acknowledges that the level of usability depends highly on the intended context of use (e.g., users, hardware, software, and social environments). Researchers have demonstrated that the three ISO usability components are distinct. Frøkjær, Hertzum, and Hornbæk (2000) found only a weak relationship among the three usability components. Walker, Fromer, Di Fabbrizio, Mestel, and Hindle (1998) found that efficiency did not translate into user satisfaction. These empirical studies suggest that efficiency, effectiveness, and satisfaction may be independent aspects of usability and a causal relationship among them may be weak or even nonexistent.
TopOther Dimensions Of Usability
Findings from studies such as Sing (2004), Hilbert and Redmiles (2000), and McLaughlin and Skinner (2000) support ISO recommendation in that usability is highly contextual and is built on factors such as the user’s past experience with similar systems, the role they play, and the environment the product is used in. In addition, user expectations and priorities toward usability also depend on the role they play and the position they hold.
Sing (2004) cites studies that include software usability components of (a) flexibility: users perceive the system can adapt to their preferred style of interaction, (b) ease of learning: users perceive that it is easy to gain required knowledge to achieve a satisfactory level of competence, and (c) ease of remembering: it is easy for users to recall system features after a period of time.
Hilbert and Redmiles (2000) offer similar dimensions of usability: (a) learnability: the system is easy to learn and (b) efficiency: the system is efficient to use. Once a user masters the system, a higher level of productivity is possible: (c) memorability: the system should be easy to remember even for casual users, (d) errors: the system should have a low error rate and (e) satisfaction: the system should be pleasant to use.
McLaughlin and Skinner (2000) examined five usability components on new IT implementations: (a) checkability: the system’s ability to ensure information correctness, (b) confidence: users’ confidence in their ability of using the system and also in the system itself, (c) control: the system offers the user control, (d) ease of use, (e) speed of use, and (f) understanding.
Key Terms in this Chapter
Multimedia Technologies: Hardware and software such as the Internet, Web sites, e-mail, chatrooms, blogs, wikis, podcasts, instant messaging, VoIP, shared desktops, and tele/Web/video conferencing.
Mentee: A person being mentored, usually younger and less experienced than a mentor.
Technology-Supported Virtual Community: A virtual community where members interact using a variety of multimedia technologies.
Mentor: A trusted and significant person, usually older with considerably more experience, who works with a mentee to help them learn things more quickly or earlier, or to learn things they otherwise might not have learned.
Virtual Community: A group of people who may or may not meet one another face-to-face, and who exchange words and ideas through the mediation of multimedia technologies.
Community: Networks of interpersonal ties, usually colocated, that provide sociability, support, information, and a sense of belonging and social identity.