Tree Map

A tree map is a graphic of hierarchical data represented by nested, tiled, colored rectangles. Every branch of the hierarchical tree is assigned a rectangle, which in turn is tiled with successively smaller rectangles corresponding to sub-branches. Rectangle area is proportional to a specified data attribute (for example, count ). Rectangle color denotes either the same or some other attribute (for example, lower limit ). Shown below is an example.

Major benefits of tree maps include:

•	Efficient use of space, enabling a large number of items to be simultaneously displayed.

•	Ease of pattern identification when size and color correlate well with hierarchical structure.

See also Heat Map and Dendrogram .