Regular treemap layouts for visual analysis of hierarchical data

Figure 1: Three Grid TreeMap variants applied on a hierarchically structured data set of 35 time series objects. Hierarchical relationships play an utmost important role in many application domains. The appropriate visualization of hierarchi-cally structured data sets can contribute towards supporting the data analyst in effectively analyzing hierarchic structures using visual-ization as a user friendly means to communicate information. Infor-mation Visualization has contributed a number of useful techniques for visualization of hierarchically structured data sets. Yet, the sup-port for certain regularity requirements as arising from many data element types has to be improved. In this paper, we analyze an ex-isting variant of the popular TreeMap family of hierarchical layout algorithms, and we introduce a novel TreeMap algorithm support-ing space efficient layout of hierarchical data sets providing global regular layouts. We detail our algorithm, and we present applica-tions on a real-world data set as well as experiments performed on a synthetic data set, showing its applicability and usefulness