Census finds a sharing shortcut

Many agencies realized the value of using geospatial data with their nongeographic information system applications long ago, but there weren't easy ways to do it. As Census Bureau officials have discovered, sometimes it is simpler to find a solution yourself than wait for industry efforts to bear fruit.

In this case, officials have applied the solution to the bureau's School District Tabulation program, which provides demographic data that many state and local government officials use to make their education policy decisions.

The bureau uses data analysis software from SAS Institute Inc. to develop the program, which can deliver data about school districts' demographics, said Doug Geverdt, a demographer at the Census Bureau and project manager for the 2000 Census Tabulation.

But for some parts of the analysis, such as looking at certain data points in relation to district boundary lines, officials have shifted the SAS data over to the bureau's GIS application, ArcGIS from ESRI. In the past, the shift required some time and effort because the SAS files had to be exported in a special format before Arc-GIS could read them. The files then had to be transformed to return to SAS. Because of the hassle, Geverdt often didn't go through the process.

"You just have less desire to pursue it," he said.

A chance remark in an e-mail message to an SAS programmer initiated the solution. The company's developers created what they describe as a bridge to ArcGIS that facilitates a direct data exchange between the SAS and ArcGIS platforms.

It hasn't provided any more capability than he had before if he'd had the time, Geverdt said, but the increased speed at which data can be written back and forth has changed the way he does his job.

"Now I'm much more inclined to go back and check out hunches," he said. "By being able to get at the details more easily, I also take more opportunity to analyze things by looking at things in different contexts."

His experience with the SAS bridge has also generated a lot of interest elsewhere in the Census Bureau, he said. Some of the old divisions between programmers and analysts are starting to blur, he said, with more analysts now doing most of their own programming. As a result, more people have become familiar with the capabilities of GIS.

"Many data have some form of geo-spatial component, and I think it points to a future when GIS will be used in just about all areas of analysis," Geverdt said. "Something like the SAS bridge will be a big part in enabling that, because with it, you can choose which data to include in the analysis."