ABSTRACT
HAVING TO SHOW COMPLEX INFORMATION in twodimensions is just a fact of life in data visualization. Statis-ticians call data with more than two variables multivariate. When there are more than two variables to be shown, we have to choose from:
• leaving some variables out, • encoding some variables to less than perfectly perceived vi-
sual parameters like color,
• creating multiple visualizations, or • trying to project as much of the information as possible onto
a two-dimensional image.
