Sigma
Description :
Sigma which stands for "Statistical Interface for Graph Manipulation and Analysis" presents a statistical approach for gaining deep understanding of a graph visualization. The ap- proach follows Shneiderman’s vision that “visualizations simplify the statistical results, facilitating sense-making and discovery of features such as distributions, patterns, trends, gaps and outliers”. Thus, the addition of statistical metrics within a graph visualization tool efficiently improves exploratory data analysis and allow analysts to discover new interesting relation- ships between entities. In addition, we believe that a statistical interface can play a role as a navigation control for a large graph visualization.
Dk-Series :
Moreover than just simple statistics, Sigma make use of the Dk-Series to records the graph topology. Three different level of Dk-series has been implemented : Dk1, Dk2 and Dk3 and are used to easily break-down a graph and obtain its skeleton. The three different type of results give birth to three new layout algorithms that places the nodes and edges according their descending occurrences into the graph, therefore placing the nodes with highest degree distribution right in the middle and then adding the remaining ones around it.
Dk Timeline :
The Dk-Series attribute has been widely used in generating graphs with similar topology. We have a novel utility of the Dk-Series: the Dk timeline. By assign different 'time' stamp on each entry according to some Dk order, we add another dimension to the dataset and the user can easily interactive with different subset of the data and explore the relationship between nodes with different connectivities.
People involved :