Elementary Perceptual Tasks (EPT) Activity

Cleveland and McGill define an elementary perceptual task (EPT) is the visual task by which one uses to extract a value represented on a graph.

Source: Cleveland, W.S, McGill, R. (1984) Graphical Perception: Theory, Experimentation, and Application the the Development of Graphical Methods, Journal of the Amercian Statistical Association, Vol 79, No. 387, pages 531-554.

The ability to compare a set of values on a graph is important. Cleveland and McGill dicuss the fact that some EPTS are better for comparing values than others. The purpose of this EPT Activity is to allow you to discover which EPTs are easier for estimating and comparing a value on a graph.

Directions for Activity:

• For each slide, there will be a value specified. Provide an estimate of the value represented by the question mark.
• Specify the value in the box provided and click submit to proceed to the next slide
• If a value cannot be determined, check the appropriate box and click submit to proceed to the next slide
• A summary of the outcomes for the class will be provided after the last slide