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Centrus Enhanced Data
Set
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The Centrus Enhanced Data Set is designed for address
level geocoding. Where an address level geocode is not available, the Enhanced
data set provides cascading accuracy at the ZIP+4, ZIP+2, and ZIP Code level to
return the highest level of geocode for the address using Centrus GeoStan
technology.
The Centrus Enhanced data set is derived from the TIGER street network data and
the US Postal Service ZIP+4 Address database to create a conflated Centrus
database that benefits from both the Postal address ranges and the TIGER street
network ranges. The TANA, formerly GDT, ZIP centroid file is included to
provide the most accurate ZIP+4, ZIP+2, and ZIP Code geocodes based on the TANA
street network.
The term TIGER® comes from the acronym Topologically Integrated Geographic
Encoding and Referencing which is the name for the system and digital database
developed at the U.S. Census Bureau to support its mapping needs for the
Decennial Census and other Bureau programs.
The design of the TIGER® database adapts the theories of topology, graph
theory, and associated fields of mathematics to provide a disciplined,
mathematical description for the geographic structure of the United States and
its territories.
The TIGER® database development integrated a variety of encoding techniques
such as automated map scanning, manual map "digitizing", standard data keying,
and sophisticated computer file matching. The goal was to provide automated
access to and retrieval of relevant geographic information about the United
States and its territories.
The TIGER positional accuracy varies with the source materials used, but at
best meets the established National Map Accuracy standards (approximately +/-
167 feet) where 1:100,000-scale maps from the USGS are the source. From
whatever source, the data used to build TIGER was digitized into lat/long
coordinates with no stated projection. Because the varied sources and lack of
specified projections from those sources, officially TIGER geography does not
strictly adhere to NAD27 or NAD83 Datum. Generally, Centrus considers TIGER
data in 1983 North American Datum (NAD83).
TIGER does not contain complete ZIP Code coverage because they do not have
complete address coverage for the entire country. TIGER concentrates on
city-style addresses in their database; P.O. boxes and rural route addresses
aren't particularly useful for taking the census. TIGER uses the more
traditional "knocking on the door" approach to insure complete coverage. This
means the address, and therefore ZIP Code; coverage is not as complete in the
rural areas as it is where city style addresses are present.
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Centrus Enhanced geocoding is based on the United
States Postal Service ZIP+4 database containing 40 million ZIP+4 records in
approximately 44,000 ZIP Codes and address range records from the TIGER street
network database covering the United States and its protectorates.
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Provides geocoding and address data, for
CASS certified processing, for use with all Centrus GeoStan based solutions.
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The optional Statewide Intersection Index is designed
to enable fast intersection identification on a statewide basis as opposed to
the city/state or ZIP code basis. For example, the Statewide Intersection Index
will allow the database search for 1st and Main St, CO and return a list of
possible matches in Colorado more quickly than having to search the entire
Colorado database for each instance of the intersection.
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Map of Boulder, CO
showing the street network
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© Coyyright U.S. Census Bureau All rights
reserved
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Map of Boulder, CO
showing the ZIP+4 Centroids
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© Copyright TANA. All rights reserved
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Specifications
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Standard: Address Standardization, Address Level Geocoding, ZIP+4, Zip+2, and
ZIP Code Centroid Geocoding
Coverage: United States and Puerto Rico
Unit of Sale: National
Frequency: Monthly
Vintage:
US Postal Service Data - Monthly
TIGER
Street Network Data - Built monthly based on current TIGER Database annual
release.
TANA ZIP+4, ZIP+2, and ZIP Code Centroid Geocoding - Created monthly based on
current TIGER database quarterly release.
Source Accuracy: 167 feet (best case)
Datum: NAD83
Projection: Unprojected Lat/Lon
Format: Centrus GSD
Options: Statewide Intersection Index Data
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