Design & Graphs + R Advanced

Design Criteria

Choosing Visual Encodings

• Assume k visual encodings and n data attributes. Need to pick the best encoding among a combinatorial set of possibilities of size $(n+1)^k$
• Principle of consistency - Properties of the image should match the properties of the data
• Principle of Importance Ordering - Encode the most important information in the most effective way

Design Criteria to Follow

• Expressiveness - Tell the truth
• Effectiveness - Use proper encoding

Mackinlay's Design Algorithm

APT (A Presentation Tool)

• User formally specifies data model and type
• APT searches over design space
• Output the "most effective" visualisation

Limitations:

• Does not cover many visualisation techniques
  • Networks, maps, 3d etc
• Does not consider interaction
• Does not consider semantics/conventions
• Assume single visualisation as output

Graphs

• 1 - Univariate data
• 2 - Bivariate data
• 3 - Trivariate data

• 3 - Hypervariate data

Data Processing

• Need to clear data, and quality