CMSC 434 - Spring 2009
Prof Bederson

Introduction to Human-Computer Interaction

Homework #6: KLM (100 points)
Due 4/9/09, 11:59pm

1 (30 points) Perform a KLM analysis of the above Windows calculator using only the mouse for input to predict how long it will take to perform the calculation SQRT((27+5)*2), with the button presses indicated below. Use the KLM rules from the slides and assume that all arithmetic operators, including =, are commands. Show all steps used to reach your answer, including the rule(s) applied at each step.

2,7,+,5,=,*,2,=,SQRT.

2 (30 points) Repeat the above question for the standard Mac OS X calculator using only the mouse for input (pictured above).

3 (40 points) For each of the above two interfaces, perform a Fitts' Law analysis, and compare the KLM analysis with this Fitts' Law analysis. How does KLM predict the absolute and relative performance of the two interfaces compared to Fitts' Law?

Submission

Send your homework as DOC or PDF to the TA with "CMSC 434-hw6" in the subject line. Scoring will reflect the degree to which you demonstrate competency with the material, as well as accuracy of the result.