Aster Visualizations: When to Use Sankey Visualizations

Learn Aster
Teradata Employee

This is a multi part blog post of Aster Visualizations available in Aster AppCenter.  In this series we will describe the visuals available in AppCenter and when to use which.

In this post we will describe the Sankey Visualization:

sankey.JPG

Sankey diagrams are a specific type of flow diagram, in which the width of the connectors is shown proportionally to the flow quantity.  SA sankey diagram is a visualization used to depict a flow from one set of values to another. The things being connected are called nodes and the connections are called links.  Sankey diagrams are typically used to visualize energy or material or cost transfers between processes. 


Sankey diagrams put a visual emphasis on the major transfers or flows within a system. They are helpful in locating dominant contributions to an overall flow. Often, Sankey diagrams show conserved quantities within defined system boundaries.


Sankey diagrams are named after Irish Captain Matthew Henry Phineas Riall Sankey, who used this type ofdiagram in 1898 in a classic figure (see panel on right) showing the energy efficiency of a steam engine. While the first charts in black and white were merely used to display one type of flow (e.g. steam), using colors for different types of flows has added more degrees of freedom to Sankey diagrams.


When to Use a Sankey


Sankeys are best used when you want to show a many-to-many mapping between two domains (e.g., universities and majors) or multiple paths through a set of stages (for instance, Google Analytics uses sankeys to show how traffic flows from pages to other pages on your web site).


What I Would Like to See in Aster:


I would like to see our Sankey Diagrams mashed up with other types of graphical objects.  For example a MAP.  Perhaps the nodes are cities or points on a map:


sankmap.JPG


Sankey in a Segmented Process Flow (energy)


energysank.JPG