Database Reference
In-Depth Information
munication systems in which an “information source” selects a message and then a “trans-
mitter changes this message into the signal which is actually sent over the communication
channel from the transmitter to the receiver” (see
Figure 1-2
).
Figure 1-2. A model of communication systems
To illustrate the model, consider oral speech: the information source is the brain of a certain
person; the transmitter is this person's vocal system; the channel is the sound waves that
travel as particles in the air collide; the receiver is the auditory system of a second person;
and the destination is this second person's brain. The noise source includes other sounds
present at the time the first person speaks.
Shannon and Weaver describe how this model can apply to a wide variety of cases, including
those in which the symbols are “written letters or words, or musical notes, or spoken words,
or symphonic music, or pictures.” Put simply, the model describes the process of one mind
attempting to affect another, and it's the very essence of the human experience.
In this topic, we're dealing with the case in which the symbols communicated are abstract
graphic representations of data in the form of charts, graphs, and maps: data visualizations.
Viewing the communication of data in this conceptual framework is helpful because it re-
minds us of what we should be taking into account. Knowing how the system can fail is a
key first step.
Three Types of Communication Problems
In order to begin to understand how we can communicate data well, it's helpful to consider
the types of communication problems that Shannon and Weaver identified:
