Redundant Color Coding and Keeping-Track Performance

Abstract

An investigation was conducted to determine if performance on a keeping-track task could be enhanced by redundantly coding the displayed information channels that were being updated. At set intervals, the subject was interrogated about the status of any one of the information channels. The information consisted of numbers, colors, or numbers on a colored background, the last being the redundantly coded material. The three variables studied were channel value, payoff ratio, and coding condition. Results indicated that redundant coding did not aid performance; rather, it provided the subjects extra cues and increased the number of strategies that were used. As in previous studies, selective attention to the high-valued channels was a function of channel value and payoff ratio.

Review and Analysis of Color Coding Research for Visual Displays

“…These studies represent a wide range of experimental tasks and dependent measures. Three studies reported only information transmitted in an absolute identification task (Anderson and Fitts, 1958;Egeth and Pachella, 1969;Garner and Creelman, 1964); four reported only the percent correct in an identification task (Allport, 1971;Alluisi and Muller, 1958;Mackworth, 1963a;1963b); one reported the number of trials on which a counting error occurred (Smith and Thomas, 1964); and one reported the percent correct in what was clearly a short-term running memory task (Kanarick and Petersen, 1971). …”

“…A related issue, that of using color as an aid in organizing stimulus input, was examined by Kanarick and Petersen (1971) in a shortterm running memory study. They required subjects to monitor a row of 10 channels of information.…”

“…Again, identification accuracy was improved, but not as much as when redundant color is added to sizebrightness combinations. The addition of redundant color to digits had only a very small positive effect over digits alone in the running memory study of Kanarick and Petersen (1971). Figure 7b compares colored displays with achromatic displays of maps, static ground and aerial photographs, and dynamic aerial photographs and simulated sensor displays.…”

Perceived versus Actual Value of Color-Coding

“…An example of a symbol that would be associated with color would be a 0 which is associated with red. The use of numbers as symbols was avoided because previous research has shown that people will keep track of numbers rather than colors when presented with both (Kanarick, 1971). In other words, the purpose of this experiment was to determine the effects of color-coding, not the effect of the type of symbol used.…”

“…The tests were counterbalanced to avoid systematic bias. Four subjects in each group were tested with 4 states and then with 6. The other four were tested with 6 states before being tested with 4 states.…”