A Study of Human Pointing Features on Touch-Screens -Age Effect, Difference by Gender, and Difference in Direction-

Abstract

We set up guidelines for designing graphic user interfaces (GUI), e.g., software-keyboards, for touch screens easier to used than conventional input (or interface) devices for IT systems such as keyboards and mice. We studied aging and gender differences in the dynamic properties of user pointing on a touch screen. We obtained the following results: (1) Standard Fitts’law did not hold very well when subjects repeated pointing using one finger between two targets close together on the touch screen. Movement-Time (MT) -the time required for pointing- increased linearly with the index of difficulty (ID) - the ratio of distance between targets (D) to target size (S). (2) Neither α -the ratio of the increase of MT to ID- nor β -MT when ID is 0- differed significantly between men and women. (3) α took almost the same value in older, middle-aged, and younger subjects, whereas β differed significantly between these groups. β increased linearly with age. (4) α and β did not differ significantly between left-right and depth in pointing. (5) The practice effect reduced the dispersion of α and β.