Complete 8 page APA formatted essay: Human-Computer Interaction.Download file to see previous pages... Back in the 80’s, when human-computer interfaces were born, the factors of ergonomics and user-

Complete 8 page APA formatted essay: Human-Computer Interaction.

Back in the 80’s, when human-computer interfaces were born, the factors of ergonomics and user-friendly design were mostly ignored, which led to dissatisfied users and threatened the life of the interface. But as the computer software and hardware industry developed, so did the methods of evaluation of these products. The development and innovation in computer systems, may it be software or hardware, requires constant usability testing and interface modifications. This technique is used to evaluation a product by testing it on users. This is inarguably an irreplaceable testing practice since it gives a direct input on how users use the system (Nielsen, J.,1994). These modifications need to take place constantly thorough the development cycle of a particular software or hardware. Various methods can be employed in order to test and evaluate a particular computer interface in development. . A. USER-BASED TECHNIQUES An array of techniques is available for evaluating the usability of a particular interface. Overall, these techniques can be classified in the following categories: 1. User-Based The user-based method, as the name implies, takes real users as a testing medium. This method yields the most reliable and valid results as it directly analysis the feedback from the user. In this technique, a group of users are provided with the test interface in a defined environment or out in the field. They interaction with the interface is closely observed with emphasis on how they use that particular software or hardware to complete their task. Speed is also one of the primary gauges. After the task is complete, users are then interviewed and are asked to describe their own experience and perception of the interface. Thus, using this data and feedback, the interface can be further improved which will eventually improve the satisfaction level of the user. The user-based evaluation procedure is usually video recorded and analyzed later. However, this evaluation can also be in the form of a joint interaction between the user, the evaluator and the interface under evaluation. This enables the evaluator to get a more hands-on feedback from the user. Ideally, a large group of users would provide a more concrete feedback, but this is not always logistically possible. As a result, there is a considerable interest among HCI professionals in how to get the best feedback from the smallest focus group. While popular myths exist about being able to determine a majority of problems with only 2 or 3 users, it is believed that a sample size requirement is largely dependent on the type of errors one seeks to identify and their relative probability of occurrence. Whereas 3 users might identify many problems in a new application, substantially more users will be required to tease out the remaining problems in a mature or revised product (Lewis 1994). 2. Expert-Based Once again, as the name suggests, an expert-based evaluation is when an HCI expert evaluates the application in order to determine and forecast its usability in the hands of the user. Obviously, this method is far more cost efficient and quick as compared to the user-based evaluation as it does not involve hiring a focus group and then analyzing their feedback. In HCI, two common expert-based usability evaluation methods are Heuristic evaluation (e.g., Nielsen, 1994), and Cognitive Walkthrough (Wharton et al, 1994). In the Heuristic method, the evaluator is provided with a simple checklist made according to a set guideline which he uses to evaluate the application step by step. Any incompliancy of the application with respect to the list is treated as a problem.