4: For Communication and Storytelling
But what about visualizations that communicate to others? This is perhaps the most challenging area of visualization. Charts and other forms of information graphics have been around for centuries, but the computerized process of taking data and using it to generate graphics is relatively new and rapidly changing as we speak. While you can sometimes create a very clear and compelling chart at the touch of a button now, visualized data sets often demand that the viewer be given a fair amount of hand-holding. Many viewers are not necessarily used to reading visualizations critically.
For static charts published in print or posted as images, annotative overlays such as labels, arrows and descriptive text are highly important. For animated or interactive charts created with Flash, Java, Processing or other software, labels are also important. But more than that, they present the opportunity to construct a narrative that can lead the viewer through the main points of your visualization. Is it a time series showing how a particular issue took shape? Is it a general view that zooms into the specific, say birth rates across the U.S. before you zoom in on the state of Utah? There is a growing body of research and dialogue among journalists about the best practices of narrative storytelling with interactive graphics: A good survey of methods used in journalism can be found in research conducted at Stanford by Jeffrey Heer and Edward Segal: http://vis.stanford.edu/papers/narrative. There is also a documentary video about visualization in journalism at datajournalism.stanford.edu.
Other interesting examples of narrative visualization include the Swedish public health researcher Hans Rosling’s BBC program “The Joy of Stats,” the Economist Magazine’s online “video graphics,” and Pedro Cruz’s visual rendering of the decline of empires.