Human Factors Testing of Icons for PC JR'S Word Processor Application

Abstract

Problem: This paper describes a study which was done during the development of the PCjr's HomeWord word processor. The objective was to determine the extent to which menu icons were intuitively obvious. Method: Study Phase 1: 24 IBM employees were tested. Half of the subjects with WP experience and half of those without WP experience were given 10–15 minutes of “training” (operational definitions). The test consisted of two blocks of trials separated by a 15 minute rest period during which a demographic questionnaire was given. Subjects observed the icons on the screen and then completed a matched-pair multiple choice test. Included in the choices was a false choice to minimize guessing. Subjects' confidence level and subjective responses were also obtained. A confusion matrix was developed to identify which choices were made for each icon. Those icons which fell below a 90% correct identification cut-off were analyzed further. The Fisher Exact Probability Test was used to determine whether the correct selection of an icon and its function was dependent upon WP experience or the abbreviated “training”. Comments of the subjects were categorized and tabulated. Study Phase 2: 31 dependents of IBM employees, aged 8–18, were tested with icons representing a subset of basic WP tasks. The test design was the same as that for adult testing except that (1) all subjects were trained and tested in the same way, (2) training was more extensive, (3) no false choice was in the test instrument, and (4) confidence level data was eliminated after the pilot test. The test data were analyzed as for the adult testing except that (1) no confidence level data was used, and (2) a regression line was fit to identify icons vs. age. Comparisons were also made between test data for adults vs. minors. Results: Major results indicated that displaying all icons in a menu enhanced learning; the original design of several critical icons, e.g., Save Document vs. Delete Document, were confusing; and effective learning of the icons began at about 10 years of age. Conclusion: The improved icon designs added significantly to the salability of the product by eliminating confusing menu icons. Acknowledgement: This is to acknowledge the support of Mr. J. Lewis in the analysis and reporting for Study Phase 1.