Popping the bubble: do bubble plots distort interpretation of circle size?.

Abstract

This research tested the hypothesis that an Ebbinghaus illusion can occur in a bubble plot display and thus distort the interpretation of circle size. In order to do this we tested participants’ ability to judge circle size in different bubble plot conditions. These conditions varied based on how likely they were to cause an Ebbinghaus illusion to be present in the plot. The research found that conditions that were more similar to the Ebbinghaus illusion showed greater distortion and were distorted in the correctly theorized direction. The implications of these distortions were then assessed based on theoretical guidelines of good visual displays of data.