GEOGRAPHIC INFORMATION SYSTEMS AND THE ODYSSEY PROJECT

Abstract

There are numerous public and private agencies that are currently creating geographic (location specific) data. These agencies include the Census Bureau (County DIME, Urban Atlas, DIME files), the United States Geological Survey (Land Use Series), the Central Intelligence Agency (World Data Banks I and II), NASA (LANDSAT), the Soil Conservation Service (soil surveys) and others. In addition, there are an increasing number of commerical service bureaus offering geographically referenced data. A major problem facing planners, resource analysts, marketing analysts, mathematical geographers and others is the ability to combine these different coverages into a common data base (population, land use, sales areas, zoning districts, etc.), and the ability to comparethese irregular coverages by means of the analytical process of polygon overlay in order to create a composite coverage. This latter task would give the analyst the ability to display a map of, for example, employed persons between the ages of 40 and 50, paying between $2000 and $3000 in real estate taxes and aggregated to congressional districts. The ODYSSEY project of the Harvard Geographic Information System was designed to respond to these problems. ODYSSEY is an open-ended series of program modules that interactively create, manipulate, edit and display geographic data. More specifically, the ODYSSEY programs create data bases by integrating data from a variety of sources, enabling the manipulation of a data base (along with its associated attributes), performing analytic tasks on the data, such as polygon overlay, and displaying the results as colored or black and white thematic maps.