Points of view: Plotting symbols

Journal name:
Nature Methods
Volume:
10,
Page:
451
Year published:
DOI:
doi:10.1038/nmeth.2490
Published online

Choose distinct symbols that overlap without ambiguity and communicate relationships in data.

At a glance

Figures

  1. The hollow circle is a flexible and robust plotting symbol.
    Figure 1: The hollow circle is a flexible and robust plotting symbol.
  2. Symbol diversity can be achieved by varying shape, fill or color.
    Figure 2: Symbol diversity can be achieved by varying shape, fill or color.

    (a) Symbols that contrast with one another make good combinations. (b) Letters simplify legend lookups, but many appear the same (such as C/G, B/R/P and E/F/H). (c) Shapes are powerful discriminators—but beware that, for a given width, they may appear to have different sizes owing to differences in areas. (df) Color is one of the differentiators (d). For black-and-white applications, vary the fills for low data densities (e) and use texture symbols when overlap is high (f).

  3. Symbols should encode natural hierarchies in data to simplify legend lookup and help reveal patterns.
    Figure 3: Symbols should encode natural hierarchies in data to simplify legend lookup and help reveal patterns.

    (ac) The choice of encoding three different gene types in a is nonintuitive5 (for example, transcribed state is shown by a circular outline, repeating a shape already in use), and symbols overlap awkwardly (dotted regions). (b,c) Alternative symbol sets in black and white (b) and color (c).

References

  1. Cleveland, W.S. & McGill, R. J. Am. Stat. Assoc. 79, 807822 (1984).
  2. Lewandowsky, S. & Spence, I. J. Am. Stat. Assoc. 84, 682688 (1989).
  3. Cleveland, W.S. Elements of Graphing Data 2nd edn. (Hobart Press, 1994).
  4. Wong, B. Nat. Methods 8, 889 (2011).
  5. Zheng, D. Genome Res. 17, 839851 (2007).

Download references

Author information

Affiliations

  1. Martin Krzywinski is a staff scientist at Canada's Michael Smith Genome Sciences Centre.

  2. Bang Wong is the creative director of the Broad Institute of the Massachusetts Institute of Technology and Harvard and an adjunct assistant professor in the Department of Art as Applied to Medicine at the Johns Hopkins University School of Medicine.

Competing financial interests

The authors declare no competing financial interests.

Author details

Additional data