Scatter Plot Chart: Recommended Style and Tips

​

Use a Scatter Plot Chart:

​

• When you have paired numerical data;

• When the dependent variable may have multiple values for each value of the independent variable;

• When trying to determine whether the two variables are related, (i.e., when trying to identify potential root causes of a problem);

• When determining whether two effects that appear to be related both occur with the same cause.

​

Recommended Style 

​

1. Color: Use contrasting colors to identify variables within a scatter plot. Each variable should have a distinct, contrasting color.  Contrasting colors help the reader to identify and visually separate data sets. See approved colors.

2. Base line: The base line of a scatter pot chart should always start at zero. 

3. Trend Lines: Use trend lines; these help draw correlation between the variables to show trends (see chart below).

4. Labeling: When appropriate, the X and Y axis should be clearly labeled. The Y axis label should be turned 90 degrees, reading from bottom to top (see chart below). The X axis should not be labeled at an angle. Font type: Calibri Light. Font size: 11.

5. Values: When possible, remove excessive zeros from values. 

6. Title: Begin your title with the portion mark classification, followed by Figure #: Title. Font type: Calibri Regular. Font size: 14.

7. Classification and Sourcing: Below the line chart, bottom left, list the overall classification of the chart and directly below the classification, list the source and source stream/s. Font type: Calibri Light Italic. Font size: 9. 

​

Tips

​

• Consider excluding outliers if they are not important to interpreting the data.

• Don’t compare more than two trend-lines in a graph. Too many trend lines makes the data difficult to read and interpret.