Human-Computer Interaction

Spring 2016 :: ECE 69500 :: Purdue University

This is an archived site from Spring 2016 ()
Due 5/2

Final warm-up (optional)


This is a warm-up for the final exam, which will contain a similar question. This will exercise your ability to analyze, improve, and evaluate interface designs. You will find an example of a “bad” interface, analyze it (without users), sketch some improvements, and propose a plan for measuring whether the improvements were effective.

This warm-up is optional. If you choose to complete it, it will be averaged into your homework score. If not, your homework score will be the average of the first two exercises.

You may turn this in at the end of the final exam (Mon 5/2).


Find a mobile app or web site that, in your opinion, appears to have serious usability flaws. The flaws should be primarily due to the design of the interface. Avoid targets that have serious problems with stability or other factors. The problems should be fixable by modifying visible aspects of the interface and/or the interaction that it prescribes.

Create a document containing the following. Where possible use terminology from class (readings and/or lecture) and put those words in bold.

  1. Paste a screenshot(s) of the current interface.
  2. Tell what user(s) and user goals your evaluation is relative to. Remember that user goals should be independent of any particular solution.
  3. Predict how the current interface would affect each of the five facets of usability: learnability, efficiency, memorability, error-resistance (user errors), and satisfaction. Your target does not need to be bad in all of these. If appropriate, annotate the screenshot(s) to illustrate the problems.
  4. Sketch out a modification of the interface that think would make it better. A hand-drawn or electronic mock-up are equally fine.
  5. Briefly describe 2-3 examples of how your design demonstrates principles of good visual design. (≈2-3 sentences)
  6. Briefly describe 2-3 expected improvements in usability, relative to any of the facets of usability. Describe the improvements in terms of a use case that you would like to improve. (≈3-4 sentences)
  7. Suppose the developer of your target implemented your changes according to your mock-up. How could they measure the difference to see if your changes helped? Outline an evaluation plan that would cover each of the five facets of usability (above). It must include answers to the following:
    1. Who would you recruit as participants? Why? (≈1 sentence)
    2. How many participants? Why? (≈1 sentence)
    3. Between-subjects or within-subjects? Why? (≈1 sentence)
    4. In what setting? Why? (≈1 sentence)
    5. What will participants be asked to do? Give a step-by-step plan. Include any survey questions you would ask (if any).
    6. What are the risk(s) to participants? (≈1 sentence)
    7. How will you analyze the results? (≈1 sentence)


Full credit will be given to all submissions that follow the instructions above and use principles from class (readings and lecture) where appropriate.