Wednesday, November 16, 2011

Tree-Maps: a space-filling approach to the visualization of hierarchical information structures

This paper introduces a new method to visually present hierarchical information that is inherently seen in most data. The authors state that they take advantage of the  fact that spatial information can be more cognitively receptive than text and provide an interactive way for the users to view hierarchical information in the form of "Tree-maps".

The tree maps display both structure info and content of each node in the hierarchy. I particularly liked the idea of using Venn diagrams to display the files as subsets within a directory and the use of slicing and dicing so that the different levels can be viewed and filtered in a non-cluttered manner. I also do like that the files are assigned different colors within the venn diagram to indicate the weights associated with them. The structure information is clearly displayed by enclosing sub directories in an outer rectangular box implying the parent directory.

Thus the paper presents an improved way of display of hierarchical structures giving the user flexibility in interaction, keeping in mind the space utilization, conveyance of information in a neat, pleasant manner. Although the idea is great, the visualization of the 1000 files Tree map is still difficult to comprehend according to me. Agreed that the largest and smallest sub directories can be easily detected. But in cases where there are too many sub directories or files, I wish they would have something like a drill down feature and drill up feature for better comprehension and hover labels apart from the dynamic pop-up tables that give relevant info. Another idea would be to include "search" features and possibly recommendation to the users to merge similar files. For ex: if it detects VLC player and windows media player to be on different directories, it can suggest that they be in the same directory due to their similar functionality or type.