Scatter and bubble charts are useful for displaying two or more dimensions for data simultaneously. Scatter and bubble charts are often used to communicate data related to risk management, audit and SOX processes.
Multiple Chart Dimensions
Scatter and bubble charts can be used to help to identify correlations between two variables.This can help identify the potential root cause of problems.
A scatter chart is a plot of individual points that display the relationship between two sets of data. A scatter chart is used rather than a line chart when the data shows a trend rather than a direct correlation.
An example in business could be unit sales versus revenue. These two categories of information will set the location of the point. The color of the point can be another factor such as production location.
The size could be sales variance--the difference between the projected or budgeted sales and actual sales.
Dimensions for bubble charts may include the point label; X axis position; Y axis position; point sizes, shapes, and colors; and chart gradients.
The following are example data parameters that could be depicted in a scatter or bubble chart:
- Point Label Risk or Process Name
- X-Axis Risk Likeliness
- Y-Axis Risk Severity
- Size Speed of Onset
- Color Audit Phase (to compare how points move over time)
All of these dimensions can be controlled from the chart’s data table and the Chart Properties panel.
Customizing Scatter and Bubble Charts
The Chart Properties panel provides access for the General settings, plot settings and the Bottom Axis and the Left Axis settings.
Bubble Size and Shape
Bubble charts allow you to adjust the relative size and shape of the bubbles using the values in the data table or other linked source. In addition to X and Y axis points, you can add an additional column to your data table to set bubble size. Changing the range will then scale bubble sizes up and down as desired.
Use the Shape drop-down setting in the Chart properties panel to choose between shape options.