Understanding how GeoTAX processes addresses - GeoTAX_Premium - 7 - 7.7

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GeoTAX Premium for Windows, UNIX/Linux, and z/OS
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GeoTAX processes addresses in the following order:

  1. Parses the address elements.

    When you load data in GeoTAX, GeoTAX parses the data into single elements. Parsing occurs on data in the order in which you load the data. Even if a valid address is missing an element, GeoTAX can find a match. In addition, some elements, such as pre-directionals, may not be critical elements of some addresses. By comparing an address as input against all known addresses in a search area, GeoTAX can usually determine if any of these elements are missing or incorrect.

  2. Determines the search area.

    GeoTAX uses the last line elements of an address to determine a search area. You can specify if you want the search area to be based on a finance area or on an area defined by the city, state, and ZIP Code. If the city and state are not in the ZIP Code, GeoTAX performs separate searches for the ZIP Code and city.

    Note: A finance area is a collection of ZIP Codes within a contiguous geographic region.
  3. Finds possible matches within the search area.

    Once GeoTAX has determined the search area, it tries to match the elements from the street address line to the records in the standardized data files and completes the following:

    • Checks input address ranges for missing or misplaced hyphens, and alpha-numeric ranges for proper sequence.

    • Searches for any misspellings and standard abbreviations. For example, GeoTAX can recognize Mane for Main and KC for Kansas City.

    • Searches for any street name alias matches to the USPS and Spatial data (TIGER, TomTom, NAVTEQ and Points). For example, GeoTAX recognizes that in Boulder, “CO Highway 36” is also known as “28th Street”.

    Note: The USPS does not consider matches to data that they did not create and these are not considered valid addresses for postal delivery.
    • Searches for addresses that contain a house number and unit number as the same element. For example, GeoTAX recognizes the input 4750-200 Walnut Street and performs recombination to output 4750 WALNUT ST STE 200.

    • Searches for any USPS recognized firm names for additional match verification.

    • Searches for street intersection matches. GeoTAX recognizes and, &, &&, at, AT, and @ in the input address for an intersection match.

    Note: The USPS does not consider intersections valid addresses for postal delivery.
  4. Scores each possible match against the parsed input.

    GeoTAX compares each element in the input address to the corresponding element in the match candidates, and assigns a confidence level. GeoTAX weighs the confidence level for all of the elements within a match candidate, and assigns a final score.

    Note: GeoTAX uses a penalty scoring system. If an element does not exactly match an element in the match candidate, GeoTAX adds a penalty to the score of the match candidate. Therefore, scores with lower numbers are better matches.
  5. Determines the match.

GeoTAX prioritizes each match candidate based on the assigned confidence score and returns as a match the candidate that has the lowest score.

The match mode you choose determines the range that GeoTAX allows for a match. GeoTAX only returns a match if the score of the target address falls within the range designated by the selected match mode. For more information on match modes, see Using GeoTAX match modes.

In some cases, more than one match candidate may have the lowest score - this is considered a multi-match result. In this case, you have the option to set how the matching outcome will be handled: you can opt to receive the 1st match candidate, or, in the case of interactive matching, the number of matches can be returned and you can select the match candidate from the multi-match list. For more information on multi-match, see Returning multiple address matches.

GeoTAX provides information on the matching and geocoding results and processes. For more information, see Match results and return values.