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Coordinate system for shapefiles exported from GeoLytics CensusCD products

Those ACIC lab users who export a map from GeoLytics as a shapefile and then want to display these data with other GIS layers will need to know the coordinate system and--if applicable--the projection of the shapefile exported from the GeoLytics product so that this information can be assigned to the data in ArcGIS or ArcView 3.3. If this step is omitted in a GIS setting, the GeoLytics data will not display properly with data from other sources, nor will these shapefiles be capable of being projected or supporting distance or area calculations.

There is no good way to discern this information precisely (since GeoLytics' own documentation provides no metadata) but to ask the vendor directly. Katia, the data specialist in technical support, explained to me that the shapefiles that result from a data export are unprojected and are in the NAD83 (North American Datum of 1983) coordinate system. I tested this with several of our other layers on the I:\ drive and with some known distance measurements to confirm that this seems correct.