SRS 200

Assignment 3 -- Implementing a Redesign
Due Monday, October 9, 2006


Your Mission

In the last project, you proposed a redesign of some of the features of your stove based on the results of your first usability study. In this project, you will choose one of these features that you identified, redesign your prototype accordingly, and run another usability study to test this one new feature of your design. You will work in the same teams that you did for the previous assignment.

What to do

While at first glance this project may appear to be asking you to do Assignment 2 all over again, this is actually not the case at all. Here are the details. Note especially the differences between what you were asked to do in Assignment 2 and what you are being asked to do here.

  1. Your team should pick one aspect of your stove to redesign and concentrate on just that one. Be as specific as possible. Some examples of things you might choose include:

    Do not pick something too general. For example, choosing the "timer" as a whole to redesign would be inappropriate if it involves altering many things at once such as how one sets the timer, cancels the timer, set/modifies delays, etc. In other words, do not try to fix the entire stove at once. Complex interfaces have facets that interact with each other in ways you cannot foresee. If you change many things at once, you will undoubtedly fix some problems, introduce new ones, and still not be able to isolate the good from the bad usability elements. By testing one element at a time, you will be able to see how it alone contributes to or detracts from the usability of the artifact as a whole.

    We recommend making a list of two or three possible features that you may want to redesign, and then searching for related work (see #2 below) to see which design feature yields the most promising outside resources.

  2. Start researching related work early in the redesign process to see if there are other possibilities you have not yet considered. Unlike the previous project, concentrating on just one feature of the stove will allow you to perform a more focused literature search. This, hopefully, will yield publications which will speak more directly to the issues you are facing. Note that you can now perform research on the failed design from Assignment 2 too! This may also yield fruitful insights. And don't forget about using design heuristics for additional inspiration!

  3. Once your team settles on a new design, you should alter your prototype so that you can easily switch between the original design of your chosen feature and the new design. (You may need to do some ungluing, poster board cutting, or other surgery to your prototype. That's ok. Low resolution prototypes are destined for change.) Remember, don't change the prototype more than you have to, and make it easy to switch back and forth between the two designs. You may need to do this switcheroo during subject testing.

  4. Design and execute a new usability study. You will probably want to reuse some of the tasks from the first study, but only the ones that relate to your redesigned aspect. You will want to come up with new tasks too. You are required to videotape your subjects as they use your artifact. Try to capture both their facial expressions and their actions. As before, all tests should be carried out in LESS, and you should test 3-4 subjects. Also as before, it is your job to determine what protocol to use (think aloud, retrospective think aloud, etc.), whether you should use between-subject testing or within-subject testing, what to measure, and how to measure it. The discussions we have in class about videotaping should give you fresh ideas about data measurement. Feel free to use pre- and/or post-test questionnaires if you wish.

  5. The analysis of your data should include the coding of the videotape, which you will turn in as part of your final report. You should also make comparisons between the results you obtained from this study versus the results obtained from the previous study. Are there conclusions you can draw from such a comparison?

What to turn in


Each team member should continue journaling as you did for Assignment 2. Explored and unexplored design choices, interesting methods to try, results that struck you as unusual, and failed attempts are all fair game.

When all the presentations are done, you should again write a quick (1-2 page, handwritten) response to the experience. What were your expectations and actual outcomes of implementing your new design? How did it compare to other groups? What are your reflections on the videotaping and coding techniques that you used? Feel free to again comment on team dynamics too. And don't forget to record which report sections you wrote and which you collaboratively revised, as mentioned above.

We will collect your journals on Wed, Oct. 11.


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