A Comparison of Area Pointing and Goal Crossing for People With and Without Motor Impairments
By Wobbrock, Jacob O.; Gajos, Krzysztof Z.; ASSETS 2007 - The Ninth International ACM SIGACCESS Conference on Computers and Accessibility, pp. 3-10Publication Date: October 15-17, 2007
Study compared the efficacy of area pointing to goal crossing in acquiring on-screen targets using a mouse or trackball. Area pointing is a technique also known as “point-and-click,” whereas in goal crossing, a user does not have to move within a confined area and execute a click but simply moves over a goal line. Sixteen people, 8 of whom had motor impairments, participated in the study, using an optical mouse or trackball, or both. Speeds, error rates, and various path analysis measures were computed. Fitts’ law was used to model performance and to measure throughput, allowing researchers to equitably compare goal crossing and area pointing. Results showed that although area pointing was faster and had higher Fitts’ throughput than goal crossing for the able-bodied participants, the opposite was true of the motor-impaired participants, who also found goal crossing easier to perform. Path analysis measures indicated that goal crossing movement is less wiggly and deviant than movement during area pointing. However, goal crossing was found to have higher error rates under a strict definition of crossing errors. Implications for further research are discussed.
Published by: Association for Computing Machinery (Website:http://www.acm.org)
SIGACCESS (ACM Special Interest Group on Accessible Computing) (Web Site: http://www.sigaccess.org )
