Treemaps and the Visual Comparison of Hierarchical Multidimensional Data

Treemaps have the desirable property of presenting overviews along with details of data and thus are of interest in visualizations of multi-attribute tabular data with attribute hierarchies. However, the original treemap algorithms and most subsequent variations are hampered in making parallel structures in a hierarchical data structure visually comparable. Structurally parallel elements are not aligned, making it difficult to compare them visually. We propose a method that allows for proportional and non-proportional subdivisions of subtrees while preserving visual alignment of parallel structures. We extend the framework so that other types of data visualizations can be placed within the graphical areas of a treemap to allow for the visual comparison of a broad collection of data types including temporal data.