Understanding pointing problems in real world computing environments

Understanding how pointing performance varies in real world computer use and over time can provide valuable insight about how systems should accommodate changes in pointing behavior. Unfortunately, pointing data from individuals with pointing problems is rarely studied during real world use. Instead, it is most frequently evaluated in a laboratory where it is easier to collect and evaluate data. We developed a technique to collect and analyze real world pointing performance which we used to investigate the variance in performance of six individuals with a range of pointing abilities. Features of pointing performance we analyzed include metrics such as movement trajectories, clicking, and double clicking. These individuals exhibited high variance during both supervised and unsupervised (or real world) computer use across multiple login sessions. The high variance found within each participant highlights the potential inaccuracy of judging performance based on a single laboratory session.