Sri Vidya College of Engineering & Technology Question bank (unit 2) UNIT 2 TWO MARKS

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1 UNIT 2 TWO MARKS 1. What is design? Achieving goals within constraints. The design helps to focus on certain things like goals, constraints and tradeoffs Goals purpose (who is it for, why do they want it) Constraints - materials, platforms Trade-offs - Choosing goals and constraints 2. Mention about golden rule of design understand your materials.human Computer Interaction the obvious materials are the human and the computer. That is we must: i. understand computers - limitations, capacities, tools, platforms ii. understand people psychological, social aspects, human error. 3. Mention the process of design i. Requirements-what is there and what is wanted ii. Analysis- ordering and understanding iii. Design- what to do and how to decide iv. iteration and prototyping- getting it right and finding what is really needed! v. implementation and deployment- making it and getting it out there 4. What is know your user? or who are stakeholders? Over time many people are affected directly or indirectly by a system and these people are called stakeholders who are they? probably not like you! talk to them watch them use your imagination 5. What is scenarios? i. Scenarios are stories for design: rich stories of interaction. They are perhaps the simplest design representation, but one of the most flexible and powerful. In addition scenarios can be used to: Communicate with others Validate other models Understand dynamics ii. Linearity - time is linear - our lives are linear. but don t show alternatives\ iii. what will users want to do? iv. step-by-step walkthrough

2 a. what can they see (sketches, screen shots) b. what do they do (keyboard, mouse etc.) c. what are they thinking? v. use and reuse throughout design 6. What is linearity? Linearity - time is linear - our lives are linear. but don t show alternatives Scenarios one linear path through system Pros: life and time are linear easy to understand (stories and narrative are natural) concrete (errors less likely) Cons: no choice, no branches, no special conditions miss the unintended So: use several scenarios use several methods 7. Compare Levels of Interactions? PC application Website Physical device Widgets Form elements, tags and Buttons, dials, lights, links displays Screen design Page design Physical layout Navigation design Site structure Main modes of device Other apps and The web, browser, The real world! operating system external links 8. What is local and global structure? local structure looking from one screen or page out global structure structure of site, movement between screens. 9. What is grouping and structure? If things logically belong together, then we should normally physically group them together. This may involve multiple levels of structure.

3 10. What is whitespace? In typography the space between the letters is called the counter. Space can be used in several ways. (i) we can see space used to separate blocks as you often see in gaps between paragraphs or space between sections in a report. Space can also be used to create more complex structures. (ii) (ii) there are clearly four main areas: ABC, D, E and F. Within one of these are three further areas, A, B and C, which themselves are grouped as A on its own, followed by B and C together. In Figure 5.12 (iii) (iii), we can see space used to highlight. This is a technique used frequently in magazines to highlight a quote or graphic. 11. List screen design tools grouping of items order of items decoration - fonts, boxes etc. alignment of items white space between items 12. What is usability engineering? The ultimate test of usability based on measurement of user experience Usability engineering demands that specific usability measures be made explicit as requirements Usability specification usability attribute/principle measuring concept measuring method now level/ worst case/ planned level/ best case Problems usability specification requires level of detail that may not be possible early in design satisfying a usability specification does not necessarily satisfy usability

4 13. Mention the parts of usability specification for VCR 14. List some ISO usability standards 9241 Effectiveness -can you achieve what you want to? Efficiency- can you do it without wasting effort? Satisfaction- do you enjoy the process? 15. Mention different types of prototyping i.) Throw-away- The prototype is built and tested. The design knowledge gained from this exercise is used to build the final product, but the actual prototype is discarded. ii.) Incremental- The final product is built as separate components, one at a time. There is one overall design for the final system. The final product is then released as a series of products, each subsequent release including one more component. iii.) Evolutionary - Here the prototype is not discarded and serves as the basis for the next iteration of design. In this case, the actual system is seen as evolving from a very limited initial version to its final release, 16. What are techniques used for prototyping? Storyboards -need not be computer-based Limited functionality simulations - some part of system functionality provided by designers tools like HyperCard are common for these Wizard of Oz technique can be animated 17. Give benefits of design rationale Design rationale is information that explains why a computer system is the way it is. Benefits of design rationale communication throughout life cycle reuse of design knowledge across products enforces design discipline presents arguments for design trade-offs organizes potentially large design space capturing contextual information

5 18. List out types of design rules principles - abstract design rules,low authority, high generality standards - specific design rules, high authority,limited application guidelines -lower authority, more general application 19. Mention principles of usability i. Learnability - the ease with which new users can begin effective interaction and achieve maximal performance ii. Flexibility- the multiplicity of ways the user and system exchange information iii. Robustness- the level of support provided the user in determining successful achievement and assessment of goal-directed behaviour iv. Predictability- determining effect of future actions based on past interaction history operation visibility v. Synthesizability - assessing the effect of past actions, immediate vs. eventual honesty 20. Mention principles of learnability i. Familiarity - prior knowledge applies to new system, guess ability; affordance ii. Generalizability -extending specific interaction knowledge to new situations iii. Consistency - likeness in input/output behaviour arising from similar situations or task objectives 21. Mention principles of flexibility i. Dialogue initiative freedom from system imposed constraints on input dialogue system vs. user pre-emptiveness ii. Multithreading ability of system to support user interaction for more than one task at a time concurrent vs. interleaving; multimodality iii. Task migratability - passing responsibility for task execution between user and system iv. Substitutivity allowing equivalent values of input and output to be substituted for each other representation multiplicity; equal opportunity v. Customizability- modifiability of the user interface by user (adaptability) or system (adaptivity)

6 22. Mention principles of robustness i. Observability - ability of user to evaluate the internal state of the system from its perceivable representation browsability; defaults; reachability; persistence; operation visibility ii. Recoverability - ability of user to take corrective action once an error has been recognized reach ability; forward/backward recovery; commensurate effort iii. Responsiveness- how the user perceives the rate of communication with the system. Stability iv. Task conformance- degree to which system services support all of the user's tasks task completeness; task adequacy 23. List out Shneiderman s 8 Golden Rules i. Strive for consistency ii. Enable frequent users to use shortcuts iii. Offer informative feedback iv. Design dialogs to yield closure v. Offer error prevention and simple error handling vi. Permit easy reversal of actions vii. Support internal locus of control viii. Reduce short-term memory load 24. List out Norman s 7 Principles i. Use both knowledge in the world and knowledge in the head. ii. Simplify the structure of tasks. iii. Make things visible: bridge the gulfs of Execution and Evaluation. iv. Get the mappings right. v. Exploit the power of constraints, both natural and artificial. vi. Design for error. vii. When all else fails, standardize 25. What is goal of evaluation -To assess extent of system functionality -To assess effect of interface on user -To identify specific problems 26. What is cognitive walkthrough It is an attempt to introduce psychological theory into the informal and subjective walkthrough technique. evaluates design on how well it supports user in learning task usually performed by expert in cognitive psychology

7 expert walks though design to identify potential problems using psychological principles forms used to guide analysis 27. What is Heuristic Evaluation? A heuristic is a guideline or general principle or rule of thumb that can guide a design decision or be used to critique a decision that has already been made. Heuristic evaluation, developed by Jakob Nielsen and Rolf Molich, is a method for structuring the critique of a system using a set of relatively simple and general heuristics. Heuristic evaluation can be performed on a design specification so it is useful for evaluating early design. But it can also be used on prototypes, storyboards and fully functioning systems. It is therefore a flexible, relatively cheap approach. Hence it is often considered a discount usability technique. 28. What types of test available in analysis? i. Parametric - assume normal distribution, robust, powerful ii. non-parametric - do not assume normal distribution, less powerful, more reliable iii. contingency table - classify data by discrete attributes count number of data items in each group 29. What is think aloud? It is a user observed performing task and user asked to describe what he is doing and why, what he thinks is happening etc. Advantages simplicity - requires little expertise can provide useful insight can show how system is actually use Disadvantages subjective selective act of describing may alter task performance 30. Mention about query techniques? i. Interviews- analyst questions user on one-to -one basis usually based on prepared questions. informal, subjective and relatively cheap Advantages can be varied to suit context issues can be explored more fully can elicit user views and identify unanticipated problems Disadvantages - very subjective, time consuming ii. Questionnaires - Set of fixed questions given to users Advantages- quick and reaches large user group, can be analyzed more rigorously Disadvantages- less flexible, less probing

8 31. Difference between multi modal and multi media Multi-modal systems use more than one sense (or mode ) of interaction e.g. visual and aural senses: a text processor may speak the words as well as echoing them to the screen Multi-media systems use a number of different media to communicate information e.g. a computer-based teaching system:may use video, animation, text and still images: different media all using the visual mode of interaction; may also use sounds, both speech and non-speech: two more media, now using a different mode 32. List out universal design principles. i. equitable use ii. flexibility in use iii. simple and intuitive to use iv. perceptible information v. tolerance for error vi. low physical effort vii. size and space for approach and use 33. Illustrate UIMS. a user interface management system or UIMS (pronounced you-imz ) can be considered to provide such high-level programming support. The job of a UIMS, then, is to allow the programmer to connect the behavior at the interface with the underlying functionality. 16 MARKS 1. Explain in detail about the followings a. Scenario stories for design, use and reuse b. Navigationlocal structure single screen global structure whole site c. Screen design i. basic principles ii. grouping, structure, order iii. alignment iv. use of white space 2. Explain in detail about design rules, principles and standards Principles of usability - general understanding of learnability, flexibility, robustness Standards and guidelines - direction for design

9 Design patterns - capture and reuse design knowledge 3. Explain in detail about the following in detail Nielsen s 10 Heuristics i. Visibility of system status ii. Match between system and the real world iii. User control and freedom iv. Consistency and standards v. Error prevention vi. Recognition rather than recall vii. Flexibility and efficiency of use viii. Aesthetic and minimalist design ix. Help users recognize, diagnose and recover from errors x. Help and documentation Shneiderman s 8 Golden Rules ( see 23 rd 2 mark) Norman s 7 Principles ( see 24 th 2mark) 4. Explain in detail about evaluation techniques i. Cognitive Walkthrough ii. Heuristic Evaluation iii. Review-based evaluation iv. Evaluation through user participation v. Observational methods- Think Aloud, Cooperative evaluation Protocol analysis, automated analysis, Post-task walkthroughs 5. What is known as Hill Climbing Approach? Explain Prototyping is an example of what is known as a hill-climbing approach. Imagine you are standing somewhere in the open countryside. You walk uphill and keep going uphill as steeply as possible. Eventually you will find yourself at a hill top. This is exactly how iterative prototyping works: you start somewhere, evaluate it to see how to make it better, change it to make it better and then keep on doing this until it can t get any better. However, hill climbing doesn t always work. Imagine you start somewhere near Cambridge, UK. If you keep moving uphill (and it is very difficult to work out which direction that is because it is very flat!), then eventually you would end up at the top of the Gog Magog hills, the nearest thing around... all of 300 feet. However, if you started somewhere else you might end up at the top of the Matterhorn. Hill climbing methods always have the potential to leave you somewhere that is the best in the immediate area, but very poor compared with more distant places. Figure 5.15 shows this schematically: if you start at A you get trapped at the local maximum at B, but if you start at C you move up through D to the global maximum at E. This problem of getting trapped at local maxima is also possible with interfaces. If you start with a bad design concept you may end at something that is simply a tidied up version of that bad idea!

10 From this we can see that there are two things you need in order for prototyping methods to work: 1. To understand what is wrong and how to improve. 2. A good start point. The first is obvious; you cannot iterate the design unless you know what must be done to improve it. The second, however, is needed to avoid local maxima. If you wanted to climb a high as you could, you would probably book a plane to the Himalayas, not Cambridgeshire. A really good designer might guess a good initial design based on experience and judgment. However, the complexity of interaction design problems means that this insight is hard. Another approach, very common in graphical design, is to have several initial design ideas and drop them one by one as they are developed further. This is a bit like parachuting 10 people at random points of the earth. One of them is perhaps likely to end up near a high mountain. 6. What are the seven principles give as a good starting point in considering universal design? i.) equitable use: ii.) flexibility in use: iii.) simple and intuitive to use, iv.) perceptible information: v.) tolerance for error: vi.) low physical effort: vii.) size and space for approach and use