BUBBLE GRAPH / BUBBLE CHART
What is Bubble Chart? A bubble chart is used to visualize a data set with 2 to 4 dimensions. The first two dimensions are visualized as coordinates, the 3rd as color and the 4th as size. Bubble charts can facilitate the understanding of social, economical, medical, and other scientific relationships.
Bubble chart is often considered as an extension of scatter chart with the size & color factor also being introduced.
Human visual system can feel the difference in the size, but with change in the radii (3rd dimension or variable), the corresponding change in the area is non linear. Hence proper care must be taken so that the change in the area is liner by mathematically altering the change in the radius according to the variables value.
Industry Specific Example?
– Project management to compare the risk and reward among projects. In a chart each project can be respresented by a bubble,the axis can represent the net present value and probability of success and the size of the bubble can represent the overall cost of the project
– Revenue contribution from different products & sales