The effect of screen format on visual list search

Abstract

Three experiments are reported which investigate the effect of different screen formatting variables on the time it takes a subject to locate a target in a list of surnames presented on a computer screen. This has direct application to large databases such as electronic directories, where an operator must search for the names and addresses of customers in order to locate telephone numbers in response to directory assistance enquiries. The goal of this research was to isolate those factors which facilitate target recognition, and to produce a set of recommendations for screen design whenever lists of information are presented. The variables manipulated included case, spacing of surnames, alternating line format, and the insertion of blank lines between categories of information. The results indicated that subjects located targets more rapidly when screens were spaced than when they were non–spaced, and when alternating line format was used compared with non–alternating line format. No difference was found in search time between screens typed in upper case letters (capitals), compared with screens typed in mixed case letters. The insertion of a blank line between different categories of information facilitated the location of targets.

Keywords:

• Visual list search
• Response time
• Screen format
• Target location