Comparison of multiple weighted hierarchies : visual analytics for microbe community profiling

We propose visual analytics techniques to support concurrent comparison of hundreds of cumulatively weighted instances of a single hierarchy. This includes a node-link representation of the hierarchy where nodes depict the weights of all instances with high-density heat maps that are grouped and aligned to ease cross-referencing. Hierarchy exploration is facilitated by smoothly animated expansion and collapse of its branches. Detailed information about hierarchy structure, weights, and meta-data is provided by secondary linked visualizations. These techniques have been implemented in a prototype tool, in which the computational analysis concerns have been strictly separated from the visualization concerns. The analysis algorithms are extensible via a script engine. We discuss the effectiveness of our techniques for the visual analytic process of microbe community profiling experts.