Search Time with a Color Display: Analysis of Distribution Funcations

Abstract

Color displays were used for a search task. The task involved locating a particular three-digit number in a background of other numbers, given the first two digits of the target and its color. The display variables were the number of display items of the same color as the target (TCS); the number of background items not of the target's color (NOB); and the color difference between the target and background items (ΔE). Search times obtained with each of 17 combinations of these conditions were discussed in terms of their cumulative distribution functions (CDFs). The observed CDFs were compared with some theoretical CDFs: normal, linear, and exponential. Search times were normally distributed when targets were immediately obvious to searchers (TCS and NOB small,ΔE large). The exponential CDF was best when the target was less conspicuous (TCS and NOB large, ΔE small) so that searchers had to scan the display to locate the target. The exponential model was improved by addition of a parameter to represent human response time. Furthermore, the parameters of the exponential model were shown to respond in a consistent and theoretically meaningful manner to changes of the display variables.

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References

Bittner, A. C. Jr., Personal communication, April 1, 1980.

Bloomfield, J. R. Visual search in complex fields: Size diffrences between target disc and surrounding diese. Human Factors. 1972, 14, 139–148.

Carter, E. C. , and Carter, R. C. Color and conspicuousness. Journal of the Optical Society of America, 1981, 71, 723–729.

Carter, R. C. Visual search with color. Journal of Experimental Psychology: Human Perception and Performance, in press.

Carter, R. C. , and Cahill, M.-C. Regression models of search time for color-coded information displays. Human Factors, 1979, 21, 293–302.

Draper, N. , and Smith, H. Applied regression analysis. New York: Wiley, 1966.

Engel, F. L. Visual conspicuity, visual search and fixation tendencies of the eye. Vision Research, 1977, 17, 95–108.

Feller, W. An introduction to probability theory and its applications (2 vols.). New York: Wiley, 1968.

Hogg, R. V. , and Craig, A. T. Introduction to mathematical statistics. London: Collier-Macmillan, 1970.

10.

Jennrich, R. Nonlinear regression. In M. B. Brown (Ed.) Biomedical computer programs (p-series). Los Angeles: University of California Press, 1977.

11.

Jones, M. R. Color coding. Human Factors, 1962, 4, 355–365.

12.

Judd, D. B. , and Wyszecki, G. Color in business, science, and industry. New York: Wiley, 1975.

13.

Kelly, K. L. Color designations for lights. Journal of the Optical Society of America, 1943, 33, 627–631.

14.

Krendel, E. S. , and Wodinsky, J. Visual search in unstructured fields. In A. Morris and E. P. Horne (Eds.) Visual search techniques Washington, DC: National Academy of Sciences-National Research Council, Publication 712, 1960.

15.

Morawski, T. , Drury, C. G. , and Karwan, M. H. Predicting search performances for multiple targets. Human Factors, 1980, 22, 707–718.

16.

Mackworth, N. H. Stimulus density limits the useful field of view. In R. A. Monty and J. W. Senders (Eds.) Eye movements and psychological processes. Hillsdale, NJ: Erlbaum, 1976.

17.

Robertson, A. R. The ClE 1976 color-difference formulae. Color Research and Application, 1977, 2, 7–11.

18.

Schontz, W. D. , Trumm, G. A. , and Williams, L. G. Color coding for information location. Human Factor, 1971, 13, 237–246.

19.

Smith, S. L. Color coding and visual separability in information displays. Journal of Applied Psychology, 1963, 47, 358–364.

20.

Williams, L. G. Target conspicuity and visual search. Human Factors, 1966, 8, 80–92.