Chord diagrams are quite familiar these days. There are several available implementations that use hierarchical edge bundling to show a network of dependencies, but this example tool creates bold, simple chord diagrams to show the amount of connection between entities (in the example data, it’s a breakdown of email traffic between different roles in a university).
To make the diagram visually interesting and to try and give a visual impression of the ‘footprint’ of a given entity in the overall picture, gradients are used so that the chords partially take on the color of their associated entities.
Options:
Data:
The chord diagram is recent enough that it has a specific inventor — Martin Krzywinski, who popularized this diagram type in the Circos software package. Chord diagrams have lots of visual impact but I feel they have practical value only in fairly specific cases, for instance:
- When the need is to assess the degree of similarity, or degree of interrelatedness, of two systems. This is common in biotech.
- When the need is to quickly see what major connections dominate a system.
It’s not useful for several common business use cases such as process flow, so as a result, it tends to be seen more in scientific than in business contexts.
Of course, the open secret is, that any dependency graph or hierarchy can me made to look like a chord diagram just by plotting it with rotational rather than cartesial co-ordinates…!