Due February 27 CS/PSY 6750 - Human-Computer Interaction Spring 2007

Homework 2: Observing everyday interactions (ATM machine)

The purpose of this assignment is to give you further practice in observing how other people interact with an everyday device, trying to perform a well-defined task, and to reflect on why some devices are simple to use, and others are hard to use.

For this assignment, observe another classmate or some other willing person using an automated banking machine (ATM) for a deposit and for a withdrawl, from walk up to walk away (or possibly in a drive-through ATM). Write down the steps involved (like a simplified task analysis), and then inspect the interface and the interaction for anything that would pose a problem for the user in completing the two tasks.

You should focus on the human capabilities of the user such as perceptual abilities (or disabilities); cognitive or mental processing, including memory; and physical movements or responses. How does the physical device, the screen, the buttons, the interface, the flow of the transaction, etc., support or fail to support the user in completing these "simple" tasks? Also, don't forget social considerations like privacy, comfort, preferences, etc. These concepts should tie in with the lectures on human abilities and task analysis. Ask yourself questions like, Were the buttons too small (user's finger size was not considered appropriately by designer)? Was the display too hard to see for the older users, but no problem for the younger ones (design does not support what we know about aging vision)? Did the button-to-action mapping make sense (stimulus-response mappings, cognition issues)? How many times would it take to learn the steps required to complete a task (learning aspects of cognition)?

You are to write a brief report (3 pages or less) on your observations. In this report, include a clear description (aided by pictures, perhaps) of the ATM (and its location) you chose and the specific task you wanted to observe people performing. Then you are to summarize the observations you made of other people trying to use the object to perform that task. Finally, try to come up with some sort of story about what, if anything, about the design of this ATM failed. You should try to use the principles from the DFAB book or the heuristics that Norman describes to back up your story, and support your observations and conclusions with some of the things we know about human abilities.

Here is a sample outline of the report you should prepare:

Introduction
Where was the ATM you observed and what specific task(s) was it used for. Briefly indicate if you think the system is hard to use for its intended purpose.

Observational method
Whom did you observe (what are the characteristics of that participant?), and how did you observe that person performing the selected task?

Results of observation
What were the results of your observations?

Analysis
What aspects of the task were easier/harder to complete? Why? How? Provide a theory supported by usability principles from the DFAB or Norman textbook to explain why you think the problem exists. If you observed few problems, discuss the design features that were particularly good and helped avoid problems.

Compare your observations and conclusions to other everyday objects in terms of ease of use. For example, if button size was a problem on the ATM, on what other everyday objects is it also a problem? On what other devices could it be a problem, but is not?