CS160 Midterm Exam Spring 2007
User Interface Design, Prototyping, and Evaluation

Total number of points on exam: 100

Instructions

This is a closed book, individual test.  You are not allowed to use your notes, texts, or laptop computers.  You have the full class period for this exam; there are 100 points total. Use your time accordingly.

You have brought a blank 8 ½ by 11 blue book.  Do not write on the blue book until it is handed back to you. You will hand in the blue book just before the exam starts.  The TA’s and/or I will shuffle the blue books and hand them back. Write your name and student number on the front cover of the answer booklet. Write the version number of your exam on the front cover the answer booklet.

Place your name and student number on each page containing screen shoots. When you hand in the exam, place the annotated screen shots into your answer booklet.

Each question is numbered.  Number your answers with the same number as the corresponding question.

If you find a question ambiguous, document your interpretation of the question.  Label your interpretation as “Question Clarification.”  If you write a question clarification, then label your answer “Question Answer.”  The questions on the exam are not intended to be ambiguous, but there may be other interpretations that we did not take into consideration.

Short Answer (40 points out of 100 total)

1 – 5 points

• Explain how an interface error that costs the user a few seconds per transaction can cost a company a large amount of money?
  
  Multiple users may encounter that problem multiple times a day.  This will add up to a lot of extra labor.  This labor will translate into salaries that the company is paying.
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2 – 5 points

• What are the steps of the user-centered design process?
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• Task Analysis
• Set Usability Goals
• Design User interface
• Evaluate Design Models
• Build Prototype
• Test Prototype
• Evaluate Results of Test
• Iterate Until Goals are Met

3 – 5 points

• Name five of Shniederman’s Eight Golden Rules, please use no more than eight words to describe each rule.
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• Strive for consistency
• Cater to universal usability
• Offer informative feedback
• Design dialogs to yield closure
• Prevent errors
• Permit easy reversal of actions
• Support internal locus of control
• Reduce short-term memory load
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4 – 5 points

• Why do you normally get better information about how a person performs a task when you observe him rather than ask him how he performs the task?
  
  Because people often forget steps when explaining how to do something.  When you observe them performing the task, you get to see all the steps.
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5 – 5 points

• You are deciding between using a menu based interface or an icon based interface.  List the advantages and disadvantages of each.  For a hand-held application that is used often, which is most likely a better choice?
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•             Menu –    advantages recognition over recall and structuring user’s choices.
• disadvantage of requiring significant screen space.
•              Icons –     advantages: recognition over recall and high levels of user satisfaction
•          –     disadvantages: difficult to find good icons for abstract concepts
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• Icons normally take less screen space than menus and on hand-held devices screen space is at a premium. This is normally the driving factor in choosing icons over menus for hand-held devices.
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6 – 5 points

• On of Nielson's usability heuristics is recognition rather than recall.  Explain how this heuristic relates to the model human processor.
  
  1. Humans have limited short-term memory.  By providing the user something to recognize, the "memory" is external, not using the human's short-term memory.
  
  2. Moving information from long-term to short-term memory is difficult and time consuming.  This is the process of recall.  Recognition requires less information to be moved from long-term to short-term memory.
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7 – 5 points
Why is it good to draw a user in the first frame of a storyboard being used to help develop an interface?

Because it keeps the design process focused on the user.

8 – 5 points

• How do windows support task switching?
  
  Each window can be used to store the information related to a particular task.  The windows function as reminders of what tasks the user has in progress and the state of these tasks.

9 – 5 points

• Name 4 things you can do to elevate ethical issues in performing a usability study.
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  Make the study voluntary with informed consent.
• Avoid pressuring the test subject.
• Let the test subject know that he/she can stop at any time.
• Stress that you are testing the system, not the test subject.
• Anonymize the results such that the results cannot be traced back to the test subject.
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10 – 5 points

• Name 5 of Grudin challenges for CSCW?
  
  Disparity between those who benefit from the App and those who have to do the work
• Critical mass needed to make the App useful.
• Disruption of social process.
• Exception handling.
• Unobtrusive accessibility.
• Difficulty in evaluating.
• Failure of intuition.
• Adoption process.
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11 – 5 points

• If a user has not yet reached the concrete stage of learning relative to an interface, what would user not be able to do?
  
  The user would not be able to name the components in the interface, nor be able to name the operations that are possible.  He/she would not be able to plans on how to complete new task, or describe the steps used to complete a task.
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12 – 5 points
Define what it means for a breakdown to happen in an interface metaphor and give an example.

An interface metaphor breakdown happens when the effect of an action in the interface is different from what the action would be in the domain from which the metaphor is drawn.  An example is moving a disk into the trash in the desktop metaphor used on a Mac.  The disk is not destroyed, but it in ejected from the computer.

Long Answers (60 points out of 100 total)

L1 – 20 points
Compare the advantages and disadvantages of the three different methods of testing interfaces described in class.


We covered three methods of testing interfaces in detail: user testing(UT), cognitive walkthrough (CW)  and heuristic evaluation (HE).  UT and HE are task based the last is a review based method.  Both task based methods have the advantage that they detect if there are problems in being able to complete the task. Neither of these methods is particularly good at testing for issues of consistency in the interface structure. HE is normally much better at testing for consistency.

CW and HE are both methods that do not involve testing the interface with users.  Because of this, both can be performed quickly and at little cost compared to UT. They also can be performed more easily on partially complete designs.  CW and HE have the disadvantage that they are not testing with users. This can lead to identify problems that are not really problems for the user and can overlook issues that the user would actually find difficult. This is often the case because the persons performing these testing methods normally have different knowledge and experience that the intended users of the system.

UT provides the most realistic results because it is testing with real users. UT is the most time consuming and expensive of the methods we discussed in class.  The results of UT can be difficult to understand because the user may not explain why they performed a specific action. Also, in some cases, it is hard to get test subject.
L2 – 20 points
In the following screen shots from an application, identify violations to Nielsen’s Heuristics (listed below). Annotate the screen shots to describe (1) which heuristic was violated, (2) what part of the screen shot is problematic, and (3) briefly why the heuristic was violated. You should look at all screenshots; all of them could have usability violations. However, not all screenshots will necessarily have usability violations.

Nielsen’s Usability Heuristics:

1. Visibility of system status
2. Match between system and the real world
3. User control and freedom
4. Consistency and standards
5. Error prevention
6. Recognition rather than recall
7. Flexibility and efficiency of use
8. Aesthetic and minimalist design
9. Help users recognize, diagnose, and recover from errors
10. Help and documentation

The following shows the user interface of wGetGUI: a graphical front end to a webgrabber application. A webgrabber allows complete sites to be downloaded ( including pictures and sounds) onto a client machine for "offline" browsing. wGetGUI allows users to visually set webgrabber’s flags to control what will be downloaded.

The application supports both novice and an expert interfaces: