Population Stereotypes in the Direction of Motion of Thumbwheel Switches

Abstract

No population stereotype relating direction of movement of a thumbwheel switch and the increase or decrease of the number it displays was found in a test with ninety subjects, half of whom were instructed to change the setting from 2 to 4 (increase setting), the other half from 4 to 2 (decrease setting). In the interest of uniformity, upward-to-increase is recommended as the preferred human engineering practice. A recommendation is also made to decrease required torque and to increase the accessibility of the gripping surface.