Dot plots presenting Lyme disease distribution

"With the growth of data in volume and complexity, data analysis requires sophisticated tools to uncover hidden structure. For initial exploration, dot plots are an invaluable tool for revealing the statistical distribution of a batch of data. Specifically, each dot presents a single observation on a continuous scale with symbols, usually circular dots. My master’s thesis is about revising one-dimensional dot plots, and then extending them to multidimensional dot plots. To depict the idea of dot plots, I implemented a multidimensional dot plot visualization tool, called NDplots. This image shows an application of NDplots in which two-dimensional dot plots are used to present the distribution of Lyme disease in the United States from 2005 to 2007. These county-level Lyme disease data are provided by the Centers for Disease Control and Prevention (CDC). In particular, dots are stacked directly where the Lyme disease cases are reported based on the dot size. If we use a small dot size, the dot stacks present county-level Lyme disease distribution. If we use a larger dot size, the dot stacks present state-level Lyme disease distribution. When the user clicks on the dot, the name of the county, name of state and number of incidents from 2005 to 2007 are displayed. Moreover, the dots can be colored by year as depicted in this image."