How To Interpret a Bubble Chart

With a greater emphasis than ever on master data management in 21st-century industries, it’s not only important to have the correct information but also to display it so that it makes sense. Data visualization has expanded beyond just listing out data points in an Excel spreadsheet or creating a standard bar graph. Sometimes, more is needed visually to convey what trends and patterns have been discovered. One of the ways that this is being displayed is through a bubble chart.

What is a bubble chart?

Bubble charts, also known as bubble plots or bubble graphs, are used when data needs a third dimension to provide a better view of a set of values, what they represent, and what patterns and trends may have been uncovered. Bubble charts are relational, designed to compare three variables. While three-dimensional charts usually rely on three axes, a bubble chart is represented on two axes and the size of the bubble displays a third, vital piece of information.

If you’re unsure of how to interpret a bubble chart, you’ll want to know that this critical third dimension is usually not directly dependent on the two dimensions perhaps better seen in a bar chart. While a standard line graph might show the spend on a certain type of item, bubble graphs include extra information. Bubble graphs are good for studying relationships but not for delivering the exact numeric values that another chart type may deliver. The growth rate of a bubble’s size provides readers an estimate and context on growth rate.

How do you read a bubble chart?

Like every two-dimensional chart, a bubble chart has an X- and a Y-axis. These variables are chosen for a pre-existing relationship or to determine if there is an unnoticed trend. The size of the bubble is used to represent the gravity of a parameter. This is often the population size of each country. For representing large volumes of data, bubbles of different colors are used to mark differences. This will come with a key to identify differences, such as the location of retail operations across states or countries. It can also be used to deviate the regions based on this third variable.

There are features that every bubble plot should have in place. Bubbles on a bubble chart don’t behave like others. They are unique in their discoveries. These are referred to as outliers, and they provide vital information to pinpoint why there’s a standout in these groups of numbers. As is the case with other charts, a gap in a bubble chart warrants further investigation to understand if data is missing or a key indicator is off in measurements. There are also clusters on a bubble graph. These are the opposite of outlets. Groups of bubbles indicate similarity in collecting across uniform methods.

Why do organisations use bubble charts?

A bubble chart is most beneficial when it comes to answering a binary question, such as whether the three variables being measured share a relationship or not. This can highlight a pattern, pointing out a correlation within these insights never noticed before. For example, a city’s population may increase over time as affordable housing becomes more readily available. Significant rent hikes could see those larger values become smaller. This scenario would show bubble size increasing over time as the rent was stabilized.

Bubble charts are not only useful in a socio-economic environment, but in a business context as well. This is commonly used to identify core financial processes like valuation and investment. This allows investors to monitor their assets by studying them against certain risks across standard axes representing cost and value. Bubble charts can truly make for better business decisions.