An excellent visualization, according to Edward Tufte, expresses “complex ideas communicated with clarity, precision and efficiency.” I would add that an excellent visualization also tells a story through the graphical depiction of statistical information. As I discussed in an earlier post, visualization in its educational or confirmational role is really a dynamic form of persuasion. Few forms of communication are as persuasive as a compelling narrative. To this end, the visualization needs to tell a story to the audience. Storytelling helps the viewer gain insight from the data. (For a great example, how much do you think steroids have influenced baseball?)