Visualization of data is one of the key components of analysis. The better the visual, the better the insight in to the data patterns. “Color” in a graphic is one of the key elements and in this aspect, Cartography provides valuable lessons.

Via Colorbrewer **:
image**                   Different Schemes of colouring can be used based on the data requirements :

  1. Sequential schemes are suited to ordered data that progress from low to high. Lightness steps dominate the look of these schemes, with light colors for low data values to dark colors for high data values.

  2. Diverging schemes put equal emphasis on mid-range critical values and extremes at both ends of the data range. The critical class or break in the middle of the legend is emphasized with light colors and low and high extremes are emphasized with dark colors that have contrasting hues.

  3. Qualitative schemes do not imply magnitude differences between legend classes, and hues are used to create the primary visual differences between classes. Qualitative schemes are best suited to representing nominal or categorical data.

Once you look closely at these principles, you will realize that these coloring principles can be put to use for any of the stats graph.