Logical consistency: The shapefile is converted to SDC (Smart Data Compression) format using either Esri SDC Data Development Kit Professional 2 (DDKP2) or tools in ArcGIS. The SDC data set is then loaded into ArcSDE® to verify and validate the geometry. Horizontal position accuracy: The geospatial part of this data set was extracted from the Census 2000 and 2002 TIGER/Line® files. The positional accuracy of the TIGER/Line coordinates varies with the source materials used but at best meets the established National Map Accuracy standards (+/- 167 feet approximately) where 1:100,000-scale maps from the USGS are the source. The Census Bureau cannot specify the accuracy of feature updates added by its field staff or of features derived from the GBF/DIME-Files or other map sources. Thus, the level of positional accuracy in the TIGER/Line files is not suitable for high-precision measurement applications such as engineering problems, property transfers, or other uses that might require highly accurate measurements of the earth's surface. Other data details: After processing, the data set is checked for drawing display and number of records and file sizes compared with source materials.
Notes:
U.S. Counties provides detailed boundaries that are consistent with the tract, block group, and state data sets and are effective at regional and state levels. Largest scale when displaying the data: 1:100,000. Publication date: 200701, 20070606, 20050210; Ground condition: 2000, 1997. Vector digital data.
Local Notes:
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