Hello people....

Bubble Chart

We all had a brief discussion today in the lecture on the topic Bubble chart graph and its application in interpretation of data in graphical representation.

As we studied, Bubble chart is a graphical representation of data/plot in 2D chart in relation to three distinct numeric variables/dimensions. All the plots displayed on the chart are compared in terms of sizes, and relative position of other two variables on X and Y axis of the bubble chart.

For example, we select a data range of three columns/rows and run the chart wizard and choosing one of the bubble charts

Three columns of data, appropriate for a bubble chart

X	Y	Bubble
1.43	6.80	619
2.91	5.13	695
3.95	7.57	442
4.51	4.74	716
5.91	5.25	843
6.64	7.86	270
7.04	2.97	258

The type of bubble chart representing the above data we get is,

The above graph is for a simple set of data comprising of interpretation of only one series in the chart.

If we have combination of various series in the chart, and the plot generated is as shown below,

The above chart gets very difficult for the reader to interpret comprising of many series of plots and clusters.

Thus, Bubble chart allows the user to make chart with other shapes too. The user can use squares, rectangles, thermometers, box plots and squares with all different range of colors. All other shapes would take different arguments than the circle.

Therefore interesting thing in selecting this type of chart is that you are not only limited to circular markers. You can use any marker by using the technique described in Custom Chart Series Markers as shown below.

So, Different series with different markers makes the chart more reader friendly.

Hope this information would have been useful to all.

Thank you

Source:

http://www.aventinepartners.com/aventine_partners/2009/01/bubble-charts-good-or-bad.html

http://peltiertech.com/Excel/ChartsHowTo/HowToBubble.html

http://flowingdata.com/2010/11/23/how-to-make-bubble-charts/