Bubble

Bubble charts are Scatter Plot charts where a third dimension of data is represented by the sizes of plotted objects.

Bubble

Guidelines

Use When

  • Displaying the distribution of a set of items relative to three variables, where the third variable is represented through the size of the plotted objects, i.e., Return %, Standard Deviation, and Portfolio Weight.

Don′t Use When

  • Displaying the distribution of items relative to only two axis variables. Instead, use a Scatter Plot.
  • Showing the statistical correlations among a set of items. Instead, use a Correlation Matrix.

Visual Language

  • Never use colors other than those defined in the visualization palette.
  • Always use the relevant color orders and meanings from the visualization palette.
  • Colored lines on each axis refer to each plot within the chart, precise axis data values.
  • Use hover crosshairs when it is important to be able to see a plotted item’s exact placement on each axis.
  • Use the grid view when a more precise frame of reference is needed to link plotted items and the chart axes.
Bubble chart using the grid view.

Legend

  • At container widths of 600px or less, the legend will move to the top of the chart.
  • When the legend is at the top and contains more items than fit in the available space, the full legend is accessible within a Popover triggered by an Icon-Only Button.
The Icon-Only Button provides access to the full legend within a Popover.
  • The Popover containing the full legend includes logic to prevent it from overlapping the chart unless there is no space available to the right of, or above, the data visualization.
The Popover containing the full legend has three potential positions based on the space available to the right of, and above, the chart.

Behaviors

  • When hovering over an item in the legend, all plotted items associated with that item become opaque, while all other plotted items and legend items fade back.
  • When hovering over a plotted item, the plotted item and its matching legend item become opaque, while all other plotted items and legend items fade back. A tooltip appears, surfacing the underlying data values of the holding, including its weight within its holding group.

Responsiveness

  • Bubble charts are fully fluid horizontally and vertically.
  • The tickers within the bubbles only appear when there is enough room.

Editorial

  • Strive for short, succinct axis labels and legend items that clearly describe the data.
  • Include the unit or increment in axis labels.

Code Reference

Necessary code documentation can be found in the MBC repository.

©2018 Morningstar, Inc. All rights reserved. Terms of Use