A Simple Descriptive Method & Standard for Comparing Pairs of Stacked Bar Graphs

While a plethora of research has been devoted to extoling the power and importance of data visualization, research on the effectiveness of data visualization methods from a human perceptual, and more generally, a cognitive standpoint remains largely untapped. Indeed, the way that human observers perceive and judge graphic charts can determine the interpretation of the graphed data. In this brief note we introduce a simple method for comparing stacked bar graphs based on a well-known result from cognitive science.