Database Reference
In-Depth Information
Both types of visualizations have various flavors. This chapter covers four of
them, with very different uses.
The network map is used purely to show relationships without any value
attached to the network. This is useful especially in the social media analysis
context, where the connection between items in the network, known as nodes,
is the sole arbiter of value. Other older uses for the network graphs include
the representation of computer networks, telecommunication networks, and
transport networks. In some of the versions of the network graph, direction
is included.
A color wheel, which is a wheel divided into sections with the relationships
shown as lines connecting the sections, has an added dimension in that it
can show the size of a relationship. This is useful when showing, for example,
trade balances.
Tree structures are used to represent top-down hierarchies. Organization
charts and family trees are the most well-known examples of tree structures.
The strategy map visualization, made famous by Robert S. Kaplan and David
P. Norton in their article, “The Balanced Scorecard—Measures That Drive
Performance,” is a very specific version of a tree chart. The implementation
of this tool in Performance Point also lends itself to other uses.
NETWorK MAPS
A network map shows the connections between objects visually—these con-
nections could be physical (as in the case of computer networks or railway
tracks), or they could be more abstract (as in the case of social media networks).
neTworK grAPh Theory
Network graph theory is another of the discoveries by the mathematician
Leonhard Euler, first published in his book,
Seven Bridges of Königsberg
, in
1763. In the problem statement he worked through in this topic, there are
seven bridges, and he needed to determine if one could cross each bridge
twice during a walk. A vertex (or node) is called odd if it has an odd number
of arcs (or edges) leading to it, otherwise it is even, and if a network has
more than two odd vertices, it does not have an Euler path—that is, one
cannot walk the path and cross each bridge twice.
