Shape and Color as Dimensions of a Visual Redundant Code

Studies have been conducted which indicate that redundant coding is effective in facilitating the locating of a target among other objects. This study examines that hypothesis for a range of the shape and color variables. All possible combinations of four shapes and four colors were used as targets in the experiment. The times to locate six each of the targets among 36 background objects for 16 displays in each of three coding conditions of the experiment were determined for 24 subjects. The targets could be differentiated from the background objects on the basis of color only, shape only, and redundant color/shape. The results indicate a difference among the coding conditions, the colors, and the shapes, and in the code-by-shape and code-by-color interactions. An important finding is that the redundant code and the color code conditions did not differ. The data are examined for possible explanations of this result and some implications are suggested.