Comparison of Eight Color and Gray Scales for Displaying Continuous 2D Data

Abstract

The use of various dimensions of color to encode continuous data has become commonplace with the advent of sophisticated computing hardware and software. Applications users can choose from a variety of color pallets as well as create their own for viewing digitized data sets. A primary HCI question emerging from this expanded availability of color for data display is how best to map color dimensions to data dimensions for various applications. The current study examined a subset of the perceptual/cognitive processes underlying pattern recognition tasks, whose efficacy could be affected by the nature the color scale used to visualize the data being viewed. Three types of observers' judgments were examined: absolute discrimination of a value; relative judgment of the difference between two values; and a rank order judgment of 4 values. These values were expressed in the color of a specific region in images displayed using eight different color and gray scales. Preference ratings were collected for the color scales. Grey scales were best for rank ordering tasks, while a blue-green-yellow scale proved superior for an absolute independent task. Scale preferences did not necessarily agree with performance. Implications of the findings and future research are discussed.