Conceiving and Reasoning Visualization Design Options - Data Visualization: A Successful Design Process - page 79

There are a number of ways of classifying the variety of methods for visualizing data
but here is a suggested taxonomy:
• Comparing categorical values
• Assessing hierarchies and part-of-a-whole relationships
• Showing changes over time
• Mapping geo-spatial data
• Charting and graphing relationships
Of course, there are often overlapping functional or storytelling features inherent
to the chart types that sit under these method headings. For instance, a stacked area
chart shows changes over time but also facilitates the categorical comparison of its
different layers. That would be an example of a chart type that spans across two
method classifications. However, the principle focus of this chart type is telling a story
over time and so we would consider it belonging to the "showing changes over time"
method. The comparisons it enables represent an additional but secondary focus.
As we saw in the previous chapter, the forming of data questions really helps
you articulate the range of analytical stories you are wishing to portray. In our
demonstration exercise, when we were looking to show the results of our analysis,
we were essentially responding to the question "how have the medal-winning
performances of China and Germany compared over the past five events?"