An Interaction Model for Long Pull-Down Menus

Previous studies have employed various models for exploring menu use, focusing mainly on short menus. In this study, long pull-down menus were examined in an item selection experiment. Our base model assumed that 1) the first eye fixation was located at the top, middle, or end of a menu depending on the search item; 2) menu scanning is either downward or upward; 3) the mouse was slowly moved downward from the top while scanning the target; 4) the user moves the mouse quickly to targets located at the edge of a menu; and 5) three items are scanned simultaneously. Additional models, developed by applying various assumptions, were evaluated. Experimental data showed that selection time increased based on item position and decreased for lower-positioned items in a menu having 28 alternatives, with more time needed for a menu having 50 choices because of scrolling.