Statistical Visualization of Environmental Data on the Web Using nViZn
Lacey Jones · 2002
Statistical analyses of large-scale data can often be hard to interpret. Often several pages of numbers are used to describe the data, which makes it tedious or difficult to find the numerical output that is of interest. Converting these numbers into information that is understandable and useful to someone without an extensive statistical background is also a task that is not easily accomplished. Visual representations such as maps, graphs, and charts can aid in this process. These help to better understand the information and processes the data is explaining. A recent improvement in visual statistics has been the use of the Internet. The new Illumitek software tool, nViZn, the follow-up to the Graphics Production Library (GPL), is a tool that allows a programmer to create interactive statistical displays on the Web. These displays allow a user to expand or narrow the focus of a graphical representation. It is possible to order, overlay, and rearrange the format of the data as fast as the user's Internet connection can process. Users do not need a statistical computing background to work with nViZn displays on the Web. The Internet provides easy access to such statistical displays to anyone with an Internet connection and a graphical user interface. We tested nViZn in order to determine its ability to display quality, information-rich statistical graphics. We were also interested in the difficulty of the process needed to create these displays. Our main application aimed at the display of 148 hazardous air pollutants (HAPs) for the 60,803 census tracts in the continental United States obtained from the U.S. Environmental Protection Agency's (EPA) Cumulative Exposure Project (CEP).