HCI Design Project Usability Evaluation Criteria - Research Paper Example

HCI Design Project Usability Evaluation Criteria Number Lecturer Usability Evaluation Criteria Usability is defined by ISO as “the extent to which a product can be used by specified users to achieve specified goals with efficiency, effectiveness and satisfaction in a specified context of use” (Madan & Dubey, 2012). In this context, usability is the experience of the users of an interface as they interact with the user interface in accomplishing their tasks. Evaluation of the usability of HCI design interface mainly focuses on how the users can effectively learn and use the interface to achieve their goals and objectives. It is measured by the efficiency, effectiveness and the overall user satisfaction(Madan & Dubey, 2012). Many authors have elaborated ways of carrying out an evaluation to determine the usability of an interface in different contexts. Most of these authors however have concluded to various frameworks of user interface usability evaluation based on acceptability and general user satisfaction. Most of the frameworks are composed of (Madan & Dubey, 2012); Learn ability: how easy is it for a user to learn the interface and accomplish tasks for the first time using the interface (Madan & Dubey, 2012). Efficiency: this involves how fast the user can be able to accomplish tasks after learning the new interface (Madan & Dubey, 2012). Memorability: How easily can the users reestablish proficiency after a long period of time without using the interface? Errors: what kind of errors do users make on the interface and how severe are they to the system and how easily can they be rectified? Satisfaction: how easy is it to use the interface and how pleasant is it to the user? This paper aims to provide an elaboration of the evaluation criteria by reviewing articles and literature on two major usability evaluation criteria namely; Heuristic evaluation and usability testing. Literature review Several criteria have been established for evaluating the usability of a user interface design in the current design paradigms. For purposes of this evaluation we shall focus on the heuristic evaluation and usability testing criteria that has been supported by several authors in the field of user interface design (Madan & Dubey, 2012). Jacob Nielsen is considered the father of Heuristic Evaluation criteria. He developed a set of heuristics referred to as Jacob Nielsen’s heuristics that are used for user interface design and evaluation to date (Inostroza, Rusu, Roncagliolo, Jimenez & Rusu, 2012). According to Nielsen, the main goal of the heuristic evaluation criteria is to identify the problems that are associated with the design of a user interface. He developed the criteria based on his experience as a long serving consultant of usability engineering (Inostroza et al, 2012). Heuristics are common evaluation techniques in the field of Human Computer Interaction (HCI) that is mainly conducted in the context of typical tasks that are performed by users. The designer obtains feedback from the users regarding the compatibility of the interface with their intended use and the performance in meeting their needs (Madan & Dubey, 2012). In a study carried out to determine usability of the Bogazici University Industrial Engineering website interface, heuristic evaluation was employed for evaluation of the usability of the user interface. To accomplish this task several scenarios were created for usability testing, user groups were determined based on their computing knowledge and skills. Their performance was then evaluated based on task completion success, time spent on the task, rate of accomplishment or quittance. Later, a post testing questionnaire was administered to each user to determine their personal experience using the interface (Manzari & Trinidad-Christensen, 2013). This yielded immense feedback and helped identify the various issues associated with the design of the interface. According to Manzari & Trinidad-Christensen (2003), this showed the effectiveness of the heuristic evaluation criteria in evaluating the usability of the user interface. The basic heuristics that are used in heuristic evaluation criteria according to Nielsen include: User control and freedom: the users of an interface must have adequate control and freedom of tasks. The best ways to ensure this is through use of redo and undo options (Madan & Dubey, 2012). Consistency and standards: the interface should offer enough consistency of tasks, controls and commands. Most importantly the interface should follow the conventions and standards of a particular platform (Madan & Dubey, 2012). Match between the system and the outside world: a good interface should understand the user’s needs through words, phrases and concepts and not system oriented. They should present information in a conventional and natural way (Madan & Dubey, 2012). Error Prevention: the design of the interface should minimize error occurrence as much as possible. The interface should eliminate error-prone conditions by providing checks and confirmations before performing a critical action on the interface (Madan & Dubey, 2012). Flexibility and efficiency of use: the interface should allow the user some flexibility in the use of the interface that can allow them to perform tasks more efficiently (Madan & Dubey, 2012). Recognition rather than recall: the interface should minimize the memory load of the user by making actions and objects visible. The user should not have to recall instructions and steps of using the interface but it should be visibly laid out for easy recognition rather than recall (Madan & Dubey, 2012).  On the other hand usability testing evaluation criteria involves the indulgence of the user through controlled observation of the interface. It involves observing the users as they interact with the user interface rather than asking them whether they are satisfied with the system. Usability testing mainly employs experts who observe users behavior, difficulties and emotions while performing the different tasks on an interface. Through the observation, they are able to identify areas of the interface that require improvement. It is an ideal criterion of evaluation that is best for identifying the user’s motivations and perceptions in addition to their actions (Manzari & Trinidad-Christensen, 2013). According to Manzari & Trinidad-Christensen, (2013) there are several ways of usability testing methods that can be used to evaluate the usability of the user interface. Some of these methods include; hallway testing, remote usability testing, expert review and A/B testing. Usability evaluation of a user interface can employ these criteria to determine the effectives, efficiency and user satisfaction of the user interface. Each criterion has ways of accomplishing the evaluation of user interface. However, each criteria of evaluating usability of a user interface must be evaluated on the following criteria (Manzari & Trinidad-Christensen, 2013); Effectiveness; this entails how well the evaluation method can discover usability problems of the user interface. Ease of use; how easy is the evaluation method to employ in evaluating the usability of the user interface. Ease of learning; how easy is the evaluation method to learn before using it to evaluate the usability of the user interface. Is it user friendly and comprehensible? Applicability; how easy and widely applicable is the evaluation method to the intended evaluation of the user interface? Conclusion Despite the several criteria for evaluating usability of user interfaces, all are geared towards identification of problems that are associated with the design of the user interface. Therefore, to achieve better evaluation results, it is important to choose the most reliable evaluation criteria. With that in mind, the five E’s (effectiveness, efficiency, engaging, error tolerant, easy to learn) come handy to the designer. They provide a set of characteristics that will play a great role in organizing, analyzing and presenting information collected from the users of the user interface. Once user design interface problems are identified it is important to categorize the problems in numeric format. As depicted through the heuristic evaluation criteria the problems are categorized according to their estimated impact on the user acceptance and performance. In general it is important to understand the specific targets for the usability goals that will subsequently help in planning the usability evaluation. Different criteria of evaluation have different requirements. The usability testing requires employment of users for testing of the interface, employing testing experts to carry out usability testing among others. On the other hand the heuristic criteria will not require the staff or users to perform the usability evaluation. Therefore, the best evaluation criteria would be the heuristic evaluation criteria References Inostroza, R., Rusu, C., Roncagliolo, S., Jimenez, C., & Rusu, V. (2012, April). Usability heuristics for touch screen-based mobile devices. In Information Technology: New Generations (ITNG), 2012 Ninth International Conference on (pp. 662-667). IEEE. Madan, A., & Dubey, S. K. (2012). Usability evaluation methods: a literature review. International Journal of Engineering Science and Technology, 4(2), 590-599. Manzari, L., & Trinidad-Christensen, J. (2013). User-centered design of a web site for library and information science students: Heuristic evaluation and usability testing. Information technology and libraries, 25(3), 163-169. Read More