Good Plot Symbols by Default

Abstract

Scatterplots require different symbols for different purposes. For presentation, aesthetically pleasing symbols are popular. For analysis, highly discriminable symbols aid pattern detection. This study identifies a default symbol set suitable for both presentation and analysis. This is achieved by using popular symbols with preattentive differences. Supplemental materials for this article are available online.

KEYWORDS:

• Discriminability
• Glyph
• Marker
• Preattentive processing
• Scatterplot
• Shape

Acknowledgments

The author thanks the editor and the associate editor for their constructive comments and suggestions. Dr. Randall Tobias directed the analysis in this study and helped interpret the results. Dr. Todd Barlow designed the usability tests. This work could not have been completed without the advice and support of Dr. Robert Rodriguez, Dr.Warren Kuhfeld, Dr. David Clarke, Dr. Fred Volk, Dr. Frank Wimmer, Ms. Cindy Huffman, Mr. Himesh Patel, Mr. Stuart Nisbet, and the patient participants in the opinion surveys and usability tests.

Additional information

Funding

Development of a new generation of analytical graphics software at SAS Institute provided an opportunity to study this problem.