Effects of Image and Layered Structure on Web Search Performance -Evaluation on the Basis of Movement Distance of Mouse Pointer-

The aim of this paper was to explore the effects of image addition and layered structure on Web search performance on the basis of the search time and the movement trajectory of mouse pointer. The difference of search characteristics between young and older adults was also examined. Older adults tended to take more time to search for the linked item especially when the layered structure was deep. For the deep layered structure, both young and older adults allocate more time to think which items should be selected than to operate a mouse. For all participants, less mouse movement was observed for the image-based link condition than for the character-based link condition. This tendency was more remarkable for older adults. Moreover, it was clarified that more mouse movement was observed with the increase of the number of hyperlinks per Web page. When the layered structure was shallow, the following difference of mouse operation characteristics between young and older adults was observed: Older adults made an attempt to locate the search item while moving a mouse simultaneously. On the other hand, young adults began to move a mouse after locating the search item.