To be effective, a visualization must have:
Purpose – Have a clear purpose and focus (Why are we creating this visualization? Who is it for?)
Content – Contain (only) the right information (What data matters? What relationships matter?)
Structure – Is structured correctly (How do we best reveal those data and relationships?)
Formatting – Has useful formatting (How does it look & feel? How will it be consumed?)
This talk defines these four pillars, reveal why they must be selected in this order, and discuss the importance and impact each has on your visualization.
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