Glossary - GeoTAX_Premium - 7 - 7.7

GeoTAX Premium for Windows, UNIX/Linux, and z/OS

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GeoTAX Premium
GeoTAX Premium for Windows, UNIX/Linux, and z/OS
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address elements
The components of a street address, including house number, prefix direction, street name, street type, and postfix direction. These elements are parsed by GeoTAX and should not be entered separately.
address geocoding
See geocode, geocoding.
address standardization
Address standardization is the process of taking an address and verifying that each component meets U.S. Postal Service guidelines for addresses. For example, when properly abbreviated, “123 Main Avenue” appears as “123 Main Ave.” During standardization, minor misspellings, dropped address elements, and abbreviations are corrected and the correct city, state, and ZIP Code are provided.
A recognized alternate for a street name maintained by association in the database.
alias information
Data returned with certain enums when it exists. Not returned by all enums even if specifically requested.
alternate record
Additional or differing information that may be available about a specific address but that differs from the base record. See the enums table for necessary flag settings.


base record
The principle, rather than an alternate, record within the database.
block assignments (or blockface)
For the assignment of ZIP+4 codes, one side of a street, from one intersection to the next.


Coding Accuracy Support System. A service offered to mailers, service bureaus, and software vendors that improves the accuracy of delivery point codes, ZIP+4 codes, 5-digit ZIP Codes, and carrier route information on mail. CASS provides a common platform to measure the quality of address matching software and useful diagnostics to correct software problems.
Core Based Statistical Area. A statistical geographic entity consisting of the county or counties associated with at least one core (urbanized area or urban cluster) of at least 10,000 population, plus adjacent counties having a high degree of social and economic integration with the core as measured through commuting ties with the counties containing the core. Metropolitan and Micropolitan Statistical Areas are the two categories of CBSAs.
CBSA Division
A subdivision of CBSA.
Census block ID
The 15-digit identification number used to specify a particular aggregate or block of addresses associated through census processes.
Census FIPS Code/Census ID
See FIPS code.
The calculated center of an area. The coordinates that define a centroid are the average of the sets of coordinates that describe the area.
centroid match
An address that has, through geocoding, been found to match a defined geocentroid.
city state key
A six-character USPS key that uniquely identifies a city name in the city/state file. Each city has a unique city state key.
city state name facility code
The character (A-G, K, M, N, P, S, or U) that specifies the type of postal facility.
CMSA name, CMSA number
Consolidated Metropolitan Statistical Area. The name represents the largest city in a statistical area. The number represents a 4-digit FIPS code.
The primary legal division of every state except Alaska and Louisiana. A number of geographic entities are not legally designated as a county, but are recognized by the U.S. Census Bureau as equivalent to a county for data presentation purposes. These include the boroughs, city and boroughs, municipality, and census areas in Alaska; parishes in Louisiana; and cities that are independent of any county in Maryland, Missouri, Nevada, and Virginia. They also include the municipios in Puerto Rico, districts and islands in American Samoa, municipalities in the Northern Mariana Islands, and islands in the United States Virgin Islands. Because they contain no primary legal divisions, the Census Bureau treats the District of Columbia and Guam each as equivalent to a county (as well as equivalent to a state) for data presentation purposes. In American Samoa, a county is a minor civil division.
See latitude/longitude coordinates.
Combined Statistical Area. A geographic entity consisting of two or more adjacent Core Based Statistical Areas (CBSAs) with employment interchange measures of at least 15. Pairs of CBSAs with employment interchange measures of at least 25 combine automatically. Pairs of CBSAs with employment interchange measures of at least 15, but less than 25, may combine if local opinion in both areas favors combination.


A mathematical model of the Earth used to calculate the coordinates on any map, chart, or survey system. Surveyors take an ellipsoid model of the Earth and fix it to a base point. The North American Datum (NAD) is the official reference ellipsoid used for the primary geodetic network in North America.
A geographic address line component that precedes (predirectional) or follows (postdirectional) the street name.
DPC certified
Delivery point code certified. A software or hardware device that meets U.S.P.S. standards for evaluating a properly standardized ZIP+4 code address and determines the correct 2-digit DPC and checkdigit.


Finance Area
A Finance Area is an area defined by the U.S. Postal Service from which it collects cost and statistical data. A Finance Area is frequently used for area searches, since it covers some or all of the ZIP Code areas in a town or city.
finance number
An assigned six-digit number that identifies an installation for processing it’s financial data. The first two digits are the state code and the next four are uniquely assigned from 0001 through 9999 to each installation in alphabetical order.
FIPS code
Federal Information Processing Standards code. A FIPS Code, also called a Census ID, uniquely identifies each piece of Census geography. The syntax of the FIPS code is as follows:ssccctttt.ttgbbb where:ss= the two-digit State Census FIPS Codeccc = the three digit County Census FIPS = the 6 digit Census Tract Census FIPS Codeg = the single digit Block Group Census FIPS Codebbb= the Block Census FIPS Code.


geocode, geocoding
A geocode is the geographic information associated with a unique address or centroid, such as longitude and latitude. Geocoding is the process of assigning data based upon location information. GeoTAX uses an address or ZIP Code to assign latitude, longitude, and Census FIPS information.
Geographic Information System. A computer-based tool for enhancing geographic data by analyzing both the physical location in space and the set of characteristics associated with a location.
GSD files
GeoTAX directory files.
Enumerated types in the GeoTAX API. These enums are prefixed with “GS_” and are defined in the geotax.h file.
GSU files
GSU files contain information to match addresses based on unique ZIP Code and additional highrise unit information.
GSX files
Geographic spatial index. These files are used by spatial functions in GeoTAX.


A reference to an object that is required by the Library and is not to be manipulated directly by the developer. The handle is generated when the library is initialized and is required for many library functions.


intersection matches
Intersection matches are indicated by an x___ match code. For example, the 28th Street and Valmont intersection may be standardized and geocoded and return demographic information. Intersections do not represent a valid address for mailings.


Locatable Address Conversion System. This system corrects addresses electronically for areas that have undergone permanent address conversions. The address conversion occurred as a result of the 911 system implementation and involves renumbering and renaming rural route and highway contract route information as city-style addresses with street number and name.
lat/lon; latitude/longitude coordinates
Longitude and latitude coordinates are always in degrees, and are always represented as 64-bit doubles. Positive numbers represent the Eastern and Northern hemispheres, respectively, and negative numbers represent the Western and Southern hemispheres. For example, the point 140W by 30N would be represented as –140.0,30.0. The library always assumes that the longitude coordinate is the horizontal direction and the latitude coordinate is the vertical direction. Support is not provided for user coordinates.
location code
Location codes indicate the accuracy of the assigned geocode.


mail stop designator
This designator indicates a routing code used by a company for internal mail delivery.
match code
Indicates the portions of the address that matched or did not match with the address information in the GeoTAX data files.
match mode
The algorithm used by GeoTAX to match an input address to an address in the data files.
match rates
The number of input addresses that correspond (can be matched) to address information in data files.
Minimum bounding rectangle. A geographic region defined by and minimum and maximum latitude and longitude.
Metropolitan Statistical Area
A Core Based Statistical Area associated with at least one urbanized area that has a population of at least 50,000. The Metropolitan Statistical Area comprises the central county or counties containing the core, plus adjacent outlying counties having a high degree of social and economic integration with the central county as measured through commuting.
Micropolitan Statistical Area
A Core Based Statistical Area associated with at least one urban cluster that has a population of at least 10,000, but less than 50,000. The Micropolitan Statistical Area comprises the central county or counties containing the core, plus adjacent outlying counties having a high degree of social and economic integration with the central county as measured through commuting.
MSA name/number
Metropolitan Statistical Area. The name represents the name of the largest central city and the number is the 4-digit FIPS code.
multiple match resolution
The process of resolving an address match when more than one street segment has been identified as corresponding to the input address.


The North American Datum (NAD) is the official reference ellipsoid used for the primary geodetic network in North America.
NAD27 has its origin at Meades Ranch, Kansas. NAD27 does not include the Alaskan islands and Hawaii. Latitudes and longitudes that are surveyed in the NAD27 system are valid only in reference to NAD27 and do not tie to any maps outside the U.S.
NAD83 is earth-centered and defined with satellite and terrestrial data. NAD83 is compatible with the World Geodetic System 1984 (WGS84), the terrestrial reference frame associated with the NAVSTAR Global Positioning System (GPS) now used extensively for navigation and surveying. Note that GDT uses WGS84 instead of NAD83. These two coordinate systems are compatible.
A premium vendor of street segment data.
National Customer Support Center. The U.S.P.S. CASS support center can be reached at


A basic functional unit of a library. A library contains functions that allow the user to create, manipulate, and destroy objects. C programmers access objects through handles that are provided through object creation functions.


postdirectional (postdir)
See directionals.
predirectional (predir)
See directionals.


record matching algorithm
Programmed logic that allows evaluation of the results of all field matching algorithms to determine whether two records match (i.e., are duplicates).
road class code
A key in the street segment file that identifies a road as major or minor according to the Census Feature Classification Code.
Rural Route. A delivery route served by a rural carrier.


soundex algorithm
A type of field matching algorithm that compares two fields based on their pronunciation.
soundex key
Generated by the GsSoundex function. Used to search the database by employing a soundex algorithm.
spatial query functions
Used to extract data from the GSD files. These functions specify the area to be searched through a minimum bounding rectangle rather than through city/state/ZIP or finance area.
street network files
Files provided by vendors (other than U.S.P.S.) that contain address and geocode information.


TIGER files
Topographically Integrated Geographic Encoding and Referencing. A digital database of geographic features covering the entire United States.
TIGER/Line® Identification Number. The TIGER/Line files use a permanent 10-digit TLID to uniquely identify a complete chain for the Nation. The 10-digit TLID will not exceed the value 231-1 (2,147,483,647) and represents the same complete chain in all versions of this file, beginning with the TIGER/Line Precensus Files, 1990. The minimum value is 100,001. Topological changes to the complete chain causes the TLIDs to change. For instance, when updates split an existing complete chain, each of the new parts receives a new TLID; the old TLID is not reused. As distributed, TIGER/Line files are grouped by county (or statistically equivalent entity). A complete chain representing a segment of the boundary between two neighboring counties may have the same TLID code in both counties or it may have different TLID codes even though the complete chain represents the exact same feature on the ground.
A premium data vendor of street segment files.


unit designator
Indicates the type of unit (e.g., apartment, unit).
USPS data files
Files provided by the post office containing address and ZIP Code information.


ZIP+4 directory file
Address records that contain the ZIP+4 codes for all delivery points, in an electronic form.
ZIP+4 centroid geocoding
See geocoding.
ZIP Code
Zone Improvement Plan Code. Established in 1963 the five-digit numeric code of which the first three digits identify the delivery area of a sectional center facility or a major-city post office serving the delivery address area. The next two (the fourth and fifth) digits identify the delivery area of an associate post office, post office branch, or post office station. All post offices are assigned at least one unique 5-digit code. ZIP Code is a USPS trademark.
ZIP+4 is an enhanced code consisting of the 5-digit ZIP Code and four additional digits that identify a specific range of delivery addresses. The nine-digit numeric code, established in 1981, composed of two parts: (a) The initial code: the first five digits that identify the sectional center facility and delivery area associated with the address, followed by a hyphen; and (b) the four-digit expanded code: the first two additional digits designate the sector and the last two digits designate the segment. ZIP+4 is also a USPS trademark.