Human-Computer Interaction - Assignment Example

HUMAN COMPUTER INTERACTION Lorenzo B Gould Mgmt. 320 Business Info Systems HUMAN COMPUTER INTERACTION PART ONE EVALUATION OF INTERFACES FOR COMPUTER SYSTEMS: As computer technology merges with the lives of consumers day by day, it is extremely important to ensure that the quality and ergonomics of the computer interfaces meet and exceed the demands of the target audience. 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. In the Cognitive Walkthrough method, the evaluator first determines the exact sequence of correct task performance, and then guesses the likely success or failure of the user in performing. In both methods, the expert guesses the feedback of the user and explains what parts of the interface may cause problems. 3. Model Based In the Model-Based evaluation method, the behavior of the user to handle the application is predicted beforehand. The evaluator then applies this behavior to an analytical model and determines the usability of the application. The Model-Based method is the least used out of the three. B. EVALUATING USER ABILITY All three methods of evaluating user ability have their pros and cons. The User-Based model though being the most effective, as it gives a detailed feedback from the user and identifies problems easily, is time consuming as well as costly. On the other hand the Expert-based method, is much quicker and cost-friendly than user-based system, however, the feedback of the expert may affect the true outcome of the evaluation. The Model-Based method provides a through estimate of usability; however, it misses out on the direct feedback of the consumer/user. Thus, it can be deduced that each method provides a specific result when it comes to evaluating an interface. The usage of a particular method largely depends on the information that is required in order to improve the application. BIBLOGRAPHY Nielsen, J. (1994). Usability Engineering, Academic Press Inc, p 165 Lewis, J (1994) Sample sizes for usability studies: additional considerations. Human Factors. Nielsen, J. (1994) Heuristic Evaluation. In J. Nielsen and R. Mack (eds.) Usability Inspection Methods (New York: Wiley). Wharton, C. Rieman, J.. Lewis, C. and Polson, P. (1994) The Cognitive Walkthrough Method: A Practitioners Guide. PART TWO HUMAN FACTORS 1. Practical Advantages for knowing how to use computer based systems Computer systems have creates unless possibilities in the lives of human beings. In the past 4 decades, the application of computers has almost changed the face of society altogether. From business, to communication, from entertainment to education, Human-Computer Interfaces have changed the way one lives life. Naturally, the practical advantages of the knowledge of using computer based systems are endless. Using computer based systems not only reduces the time duration of a particular task, it also ensures that the task runs error free. Another important advantage of using computer based systems is that it gets rid of the risk factor involved in various tasks that may cause harm to a human. For example, computer operated drilling machines can dig effectively and efficiently to depths that humans can just imagine. The advantages of computer systems are not only limited to professions, but education as well. Due to computer systems, it is now easier for students to overcome the barriers of distance & time. Students can now log onto a classroom and get the same quality of education through their computers. Not only the students, but teachers can also better plan their courses and gather sufficient data through research. No matter what branch of the society, computer systems now play a pivotal role in turning the cogs of world. 2. Work Advantages Computer systems have become an integral part of a profession. No matter what part of the industry one considers, computer systems have completely revolutionized the way business in conducted in the world. Taking the sensitive profession of medicine as an example, computer systems enable the professionals in an array of tasks, all the way from data processing, record keeping, research sharing, to actually performing sensitive and critical operations using computer aided equipment (Powsner SM et. al, 1998). Likewise, in the profession of engineering, computer systems have enabled engineers to perform their tasks with a 100% efficiency level. Complicated tasks are left up to the computers to perform. Design structures are passed through computer software to single out structural weaknesses and problems. The applications of Computer systems are as vast as the skies in which computer aided planes fly and as deep as the oceans thorough which computer aided ships sail. 3. The Issues of Necessity As mentioned earlier, computer systems have become an integral part of the human life. Everything, from ordering food, to performing a critical operation is now done with the help of computers. This dependency however, raises an issue of necessity in the society. The ever increasing dependency on computer systems has caused the user to demand faster, better and easier interface systems that would further create an ease for the user. Therefore, the evolution of computer systems needs to take leaps and bounds in order to meet the user requirement. BIBLOGRAPHY Powsner SM, Wyatt JC, Wright P. Opportunities for and challenges of computerization. The Lancet http://www.informatics-review.com/thoughts/advantages.html PART THREE IMPLEMENTATION 1. Perform Specific task Human-Computer Interfaces are developed to perform specific tasks as demanded by the user. Applications are specially developed keeping the needs and requirements of the user in mind. These requirements may range from a simple task like using a word processing software to an extremely complicated one like a software controlled power generation unit. Though overlap of tasks between applications is unlikely, the demands of the user are increasing in such a way, that applications are now designed to handle multiple tasks as required by the user. For example the applications in a personal computer can help the user communicate, enjoy entertainment, or even both (like the multiplayer video games of today, which offer entertainment as well as communication between friends). 2. Quantitative Analysis Human-Computer Interface applications can also be used as a vital tool in quantitative analysis. In a time and age where vital decisions are dependent on quick data analysis and processing, applications are specifically engineered to analyze complex data and display easily understandable, reliable and error free results. 3. Problems With New Applications The primary problem that new applications face is that of technical bugs that may hinder the performance of the software or hardware. These bugs are rectified through extensive testing of the interface and through upgrade and expansions once the interface has been released for the user. Another problem that new applications face is that of compatibility. As developments in computer technology is happening at lightening speed, sometimes the compatibility of an application with a particular hardware becomes an issue. A problem may also arise if the application is not thoroughly evaluated before release. This could result in user finding problems working with that particular interface and may ultimately result in user dissatisfaction. CONCLUSION Human-Computer Interaction is practically the intersection of various significant fields. Where computer science merges with behavioral science and technology design to create better computer systems and applications and provide the user with tools to accomplish everyday tasks. These applications are tailor-made for their specific task and are rigorously passed through a battery of tests and evaluations to ensure their 100% efficiency with they reach the end user. Because human-computer interaction studies a human and a machine in conjunction, it draws from supporting knowledge on both the machine and the human side. On the machine side, techniques in computer graphics, operating systems, programming languages, and development environments are relevant. On the human side, communication theory, graphic and industrial design disciplines, linguistics, social sciences, cognitive psychology, and human factors such as computer user satisfaction are relevant (Wikipedia). The basic goal of the Human-Computer Interaction is to make computer more usable and easy for the user so that he can focus more on his task at hand, rather than wasting time trying to figure out the application itself. As the world evolves day by day, through HCI, it is made sure that the software and hardware that the users use in their everyday lives is constructed and evaluated accordingly. Attention to human-machine interaction is important, because poorly designed human-machine interfaces can lead to many unexpected problems, some of which may have devastating results. Interfaces like these are used in the most critical professions and equipment, like the software running the computers of an airplane, or the computer aided equipment used in an operating theater. Thus, HCI makes sure that the applications made for the user are according to their needs and make their lives easier. BIBLOGRAPHY Wikipedia.org, 2011 < http://en.wikipedia.org/wiki/Human%E2%80%93computer_interaction#Design_methodologies> Read More