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Users And Business Functions Of Applications
- 2. Users of a system A user is the most important part of any computer system. Interface and screen design process must begin with an understanding of the system user. A system is built to serve user needs. Understanding people and what they do is a difficult and often undervalued process but very critical.
- 3. Designers should: Understand how people interact with computers. Understand the human characteristics important in design. Identify the user’s level of knowledge and experience. Identify the characteristics of the user’s needs, tasks, and jobs. Identify the user’s psychological characteristics. Identify the user’s physical characteristics. Employ recommended methods for gaining understanding of users.
- 4. Troubles with computers? Design of business systems requires behavioural training apart from technical skills. What makes a system difficult to use: Use of jargon Non-obvious design Fine distinctions Disparity in problem-solving strategies Design inconsistency
- 5. Psychological responses to poor design Confusion Annoyance Frustration Panic or stress Boredom These psychological responses diminish user effectiveness. People remember the one thing that went wrong, not the many that go right.
- 6. Physical responses for poor design Abandonment of the system Partial use of the system Indirect use of the system Modification of the task Compensatory activity Direct programming Physical responses also greatly diminish user efficiency and effectiveness. They force the user to rely upon other information sources.
- 7. People and their tasks The user in today’s office is usually overworked and continually interrupted. All computer users tend to share the following: Not to read documentation. Do not understand well the problems the computer can aid in solving. Know little about what information is available to meet their needs. Users’ technical skills have often been greatly overestimated by the system designer. Users’ objective is simply to get some work done, a task performed, or a need satisfied.
- 8. Important human characteristics in design Perception Memory Information processing Mental models Movement control Learning Skill Individual differences
- 9. Perception Perception is our awareness and understanding of the elements and objects of our environment through the physical sensation of our various senses, including sight, sound, smell, etc. Perception is influenced, in part, by experience. Perceptual characteristics: Proximity (objects are near each other in space). Similarity (objects share a common visual property). Succinctness (perfection or simplicity is easier to remember). Expectancies (we perceive not what is there but what we expect to be there).
- 10. Memory Memory is the most stable of human attributes. Long-term and short-term memory. Short-term memory receives information from either the senses or long-term memory. Within short-term memory a limited amount of information processing takes place. Information stored within it is variously thought to last from 10 to 30 seconds. Knowledge, experience, and familiarity govern the size and complexity of the information that can be remembered. Short-term memory can be increased through applying two senses: vision and audition.
- 11. Memory (continued) Long-term memory contains the knowledge we possess. The learning process is improved if the information has structure and is meaningful and familiar. Learning is also improved through repetition. Long-term memory capacity is thought to be unlimited. The difference in ability to recognize or recall words (active vocabulary is about 2000-3000, passive vocabulary is about 100000). Our power for recognition is much greater than our power to recall.
- 12. Memory (continued) We should present lists of alternatives to remind people of the choices they have. Present information in an organized, structured, familiar, and meaningful way. Placing all required information for task performance in close physical proximity. Giving the user control over the pace of information presentation.
- 13. Information processing Two levels of information processing: highest and lower levels. The highest level is identified with consciousness and short-term memory. It is limited, slow, and sequential, and is used for reading and understanding The lower level processes familiar information rapidly and without conscious effort. We look rather than see, perceive rather than read. Repetition and learning result in a shift of control from higher level to the lower level.
- 14. Mental models A mental model is an internal representation of a person’s current understanding of something. Mental models enable users to predict actions. People bring their own expectations and preconceptions based on their mental models. If the system conforms to the mental models, the use of this system feels more natural. For the design it is critical to identify and understand user’s mental models. Suggestions: design consistency and design standards.
- 15. Movement control Once data has been perceived and an appropriate action decided upon, a response must be made; in many cases the response is a movement. Movement includes such activities as pressing keyboard keys, moving the screen pointer by pushing a mouse or rotating a trackball, or clicking a mouse button. The time to acquire a target is a function of the distance to and size of the target. Provide large objects for important functions.
- 16. Learning Learning is a process of encoding in long-term memory information that is contained in short-term memory. A design developed to minimize human learning time can greatly accelerate human performance. Learning can be enhanced if it: Allows skills acquired in one situation to be used in another somewhat like it. Design consistency accomplishes this. Provides complete and prompt feedback. Is phased (requires a person to know only the info needed at that stage of the learning process).
- 17. Skill The goal of human performance is to perform skilfully. The essence of skill is performance of actions or movements in the correct time sequence with adequate precision. It is characterized by consistency and economy of effort. Economy of effort is achieved by establishing a work pace that represents optimum efficiency. Skills are hierarchical in nature, and many basic skills may be integrated to form increasingly complex ones.
- 18. Individual differences In reality, there is no average user. We all differ – in looks, feelings, motor abilities, intellectual abilities, learning abilities and speed, etc. Individual differences complicate design. In the past, it usually resulted in bringing designs down to the level of lowest abilities. The technology now offers the possibility of tailoring jobs to the specific needs of people with varying and changing learning or skill level. Multiple versions of a system can easily be created. Design must provide for the needs of all potential users.
- 19. System experience Various schemas have been proposed to classify the different and sometimes changing characteristics of people as they become more experienced using a system. We distinguish between novice user (beginners), intermediate users, and expert users. What is easy for the new user is not always perceived as easy for the old users, and vice versa. For years novice users have been told that they are stupid (Note the popularity of the manuals with “dummy” in the title).
- 20. Novice users in business systems Novice users depend on system features that assist recognition memory: menus, prompting information, and instructional and help screens. Need restricted vocabularies, simple tasks, small numbers of possibilities, and very informative feedback. View practice as an aid to moving up to expert status.
- 21. Expert users in business systems Rely upon free recall. Expect rapid performance. Need less informative feedback. Seek efficiency by bypassing novice memory aids, reducing keystrokes, summarizing information, and introducing new vocabularies.
- 22. Users on the Web Novice users: need overviews, buttons to select actions, and guided tours. Intermediate users: want systematic structure, obvious landmarks, reversibility, and safety as they explore. Expert users: like smooth navigation paths, compact but in-depth information, fast page downloads, extensive services to satisfy their varied needs, and the ability to change or rearrange the interface.
- 23. User’s knowledge/experience Computer literacy – highly technical or experienced, moderate computer experience, or none. Application experience – high, moderate, or low knowledge of similar systems. Task experience – level of knowledge of job tasks. Other system use – frequent or infrequent use of other systems in doing job. Education – high school, college, or advanced degree. Reading level Typing skill Native language or culture
- 24. Obligatory or arbitrary use Characteristics of obligatory use: The computer is used as part of employment. Time and effort in learning to use the computer are willingly invested. High motivation is often used to overcome low usability characteristics. The user may possess a technical background. The job may consist of a single task or function. Examples: a flight reservations clerk booking sets, an insurance company employee entering data into the computer, and a programmer.
- 25. Obligatory or arbitrary use (continued) In recent years, as technology and the Web has expanded into the office, a second kind of user has appeared. This kind of user is much more self-directed than the obligatory user, not being told how to work but being evaluated on the results of his or her efforts. Examples: office executive, manager, or other professional, whose computer use is completely arbitrary.
- 26. Arbitrary use General characteristics: Use of the computer or system is not absolutely necessary. Technical details are of no interest. Extra effort to use the system may not be invested. High motivation to use the system may not be exhibited. For business systems, user: Is a multifunction knowledge worker. The job can be performed without the system. May not have expected to use the system. Career path may not have prepared him/her for system use.
- 27. User’s psychological characteristics Attitude and motivation. Attitude could be positive, neutral, or negative. Motivation could be high, moderate, or low. Patience Stress level Expectations Cognitive style. Verbal thinking, spatial reasoning, analytical thinkers, intuitive users.
- 28. User’s physical characteristics Age Hearing Vision Cognitive processing Gender Handedness (about 87% are right-handed) Disabilities
- 29. Gaining an understanding of users Visit user locations, particularly if they are unfamiliar to you. Talk with users about their problems, difficulties, wishes, and what works well now. Observe (or even videotape) users working or performing a task to see what they do. Learn about the work organization where the system may be installed. Have users think aloud as they do something to uncover details. Try the job yourself. Prepare surveys and questionnaires.
- 30. Understand the business function Requirements must be determined and user activities being performed must be described through task analysis. From these, a conceptual model of the system will be formulated. The objective of this phase is to establish the need for the system! The developer should be aware of the policies and work culture of the organization being studied.
- 31. Direct techniques for determining requirements Individual face-to-face interview Traditional focus groups Usability laboratory testing Telephone interview or survey Observational field study REQUIREMENTS
- 32. Indirect techniques for determining requirements Marketing and sales Electronic survey or questionnaire E-mail or bulletin board Paper survey or questionnaire Electronic focus group REQUIREMENTS Competitor analysis
- 33. References Part 2 “User interface design process” from Galitz W., 2002, The essential guide to user interface design, 2nd Ed., John Wiley & Sons, Inc.