THE MULTIPLE VISUAL ATTRIBUTES OF SHAPE - Information Visualisation: Techniques, Usability and Evaluation - page 60

Fig. 3.27. Each glyph indicates three data attributes using curvature, angle, and a
serif.
Fig. 3.28. Stock stars: Each leg indicates three attributes of correlation via twist,
bulge, and amplitude to key securities such as oil, corn, and treasuries.
The corollary to the “like interferes with like” rule may be that like
shapes can be used for like data variables, with clear separation, e.g. by
use of a transformation such as rotation as shown in the stock stars
example.