Radar Charts!
Sheena Ellenburg
Outline
• Overview
– Characteristics
– Nomenclature
• Usage
• Examples
Overview - Characteristics
• 2-D
• 3 or more quantitative variables represented
as axes starting from the same origin
– Equi-angular spokes called radii
– Lines drawn between points to form a polygon
• Relative position and angle of the axes
generally not informative
Overview - Nomenclature
• Also known as:
– Web chart, cobweb chart (gridlines)
– Spider chart (gridlines)
– Star plot (no gridlines)
– Irregular polygon
– Polar chart (angular significance)
– Kiviat chart (acceptable range bands)
– Stardinates (Lanzenberger, 2003)
Usage
• Ideal Data:
– Multivariate (mas que 3)
– Many Quantitative to One Nominal
• Sports players attributes, companies, coffee beans
• Questions:
– Which records/observations are most similar
(clustering)
– Which records/observations are dissimilar
• Are there outliers?
When to Use a Radar Chart
• If you can’t accommodate different quantitative
scales in a bar graph
• If the objective if to compare symmetry rather
than magnitudes
– Stephen Few’s resort example
• Data fits circular display intuitively
(counter/clockwise reading order is either
explicitly obvious, or is unimportant)
– Clocked data
– Coffee bean taste attributes
Examples
Spider/Web/Cobweb Chart
Star Plot
Polar Chart
Kiviat Chart
“Stardinates”
[Lanzenberger, 2003]: Lanzenberger, M., "The Stardinates - Visualizing Highly
Structured Data", Proceedings of the Seventh International Conference on
Information Visualization (IV'03), 2003.
Cupping Scores
• SCAA Cupping
Protocols
• Sweet Marias
Coffee Achives
How to Taste an Oyster
• Tomato - The
insider's
guide to food
and drink in
Melbourne
European Sensory Network: Sensory Profiles of
three German beers
http://www.esn-network.com/635.html
More examples of food research
• http://www.cjbio.net/html/innovation/food_application.asp
• http://www.sciencedirect.com/science/article/pii/S09503293
09000226
References
•
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Kiviat Diagram: www2.cs.uidaho.edu
Polar Chart: advsofteng.com
Spider chart, star plot: wikipedia.org
Stardinates: infovis-wiki.net
Verghisgroup.com – 3 Things to Think About – A
Warning Label for Radar Charts
• Few, Stephen. Keep Radar Charts Below the Radar
– Far Below. 2005. Perceptual Edge.