Conceiving and Reasoning Visualization Design Options - Data Visualization: A Successful Design Process - page 90

One of the key concepts throughout our judgment of presentation-related design
options is to seek to make the visible, invisible. In contrast to data representation,
where our objective is to make the invisible stories and insights, visible, data
presentation features should almost feel invisible so that the portrayal of the data
maintains visual dominance. Therefore, try to bear the following two things in mind:
• Visual inference means data inference : If it looks like data, it should be data.
If it isn't data then you've incorrectly conveyed a sense of representation where
there isn't any and design refinement is required. An example might be the use
of a color to represent a certain sentiment. If that color is used on a bar chart or
is picked for the background of a label or call-out, but it is no longer connected
to the representation of any sentiment meaning, this may trick the reader who
has programmed their visual sense to spot this inference.
• Facilitating the resemblance of data : Let the data breathe. We talked about
this in the discussion about Jacques Bertin's interpretative acts, but the
presentation layers of your visualization will have a great impact on this.
Ensuring a reader can discriminate between data categories and values is
usually influenced by the background artifacts and surrounding apparatus.
Throughout your design, make sure your data stands out clearly as the
principle visual component.
The use of color
Here is a quote from Maureen Stone ( http://www.perceptualedge.com/
articles/b-eye/choosing_colors.pdf ):
"Color used well can enhance and clarify a presentation. Color used poorly will
obscure, muddle, and confuse."
We've already touched on various aspects of using color as a potentially important
visual variable for the representation of data, but the deployment of color for a
visualization project naturally extends further. Given the depth and breadth of the
field of color theory, it is important to consider it separately from our other design
choices. The preceding quote emphasizes the value of doing this.
When deployed poorly, the use of color can create unnecessary decoration that can
distract and compete undeservedly for attention in ways that will undermine the
clarity and accessibility of the information exchange.