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The State_Gen feature class is the generalized spatial representation of the United States, the District of Columbia, Puerto Rico, American Samoa, Guam, Northern Mariana Islands, and Virgin Islands. The data are an extract of the Census codes and boundaries from the following Census FTP site: ftp://ftp2.census.gov/geo/tiger/TIGER2015/. Since the Census data do not include the coastline detail, the coastal boundaries have been included through a spatial erase using the Census Hydrography data from the Census FTP site: ftp://ftp2.census.gov/geo/tiger/TIGER2015/AREAWATER/. After erasing the coastline, the data was generalized using the ESRI Simplify Polygon function. The State_Gen feature class is a US Forest Service Standard Reference Dataset and is the preferred spatial representation of US States. It should be used only for small-scale cartographic products. The purpose of the generalized State_Gen dataset is to improve map display and drawing performance in both ArcGIS applications and ArcGIS Server map services. To satisfy both performance improvement and geometry representation, the following parameters and geoprocessing method were used. Simplify the input features using the Douglas-Peucker simplification algorithm with a specified maximum offset tolerance of 375 meters. The output features will contain a subset of the original input vertices. Min scale refers to what scale the layer turns off when zooming out. Max scale refers to the scale the layer turns off at when zooming in. Min scale: 0, no minimum scale set, Max Scale: 1:4622325. |