Pitney Bowes MapXtreme - Manual (Page 337)

Chapter 18: Geocoding
Using Constraints for Accurate Geocoding
MapXtreme v7.1 344 Developer Guide
What are the Match Constraints?
The match constraints control how to match a given input address, the number or candidates
returned for each address, and what auxiliary information will be returned. An input address may not
exactly match a real world address possibly due to incomplete or incorrect information. The
GeocodeConstraints class contains a series of properties to determine which pieces of the address
are considered most important, and what to do when an exact match is not found.
The IGeocodeClient.DefaultGeocodeConstraints property can be used to retrieve the defaults from
the server or service if possible. The geocode client will use the defaults from the server or service if
no GeocodeConstraints are supplied.
Each of the following preferences impact the level of record matching that the geocode server or
service employs:
• CloseMatchesOnly – Returns only those geocoded results that are close match candidates.
The address candidates are ranked according to how closely the input address matches the
MustMatchXXX preferences. Only those candidates flagged as close matches (true) are
returned. The default is false.
• MustMatchAddressNumber – Only candidates matching the address number are considered
close. The default is true.
• MustMatchMainAddress – Only candidates matching the street name are considered close.
This does not prevent Soundex matches from being considered. (For example, "Muller Strasse"
for "Mueller Strasse" may still be considered close). It does prevent expanded street name
manipulation (misspelling), such as considering juxtaposed letters (For example, "Muleler
Strasse" for Mueller Strasse"), if the input street does not generate a close match. The default is
true.
• MustMatchCountry – Only candidates matching Country are considered close. The default is
true. It is recommended that this preference is not changed.
• MustMatchCountrySubdivision – Only candidates matching Country Subdivision are
considered close. The default is true. CountrySubdivision may be different in each country. For
example, in USA, it is state, in CAN, it is province.
• MustMatchCountrySecondarySubdivision – Only candidates matching Country Secondary
Subdivision are considered close. The default is false. CountrySecondarySubdivision are
different for each country. For example, in the USA it is county, in Canada, it is Census Division.
• MustMatchMunicipality – Only candidates matching Municipality are considered close. The
default is true. An example of a Municipality is a town or city.
• MustMatchMunicipalitySubdivision – Only candidates matching Municipality Subdivision are
considered close. The default is false. An example of a MunicipalitySubdivision is an MSA
(Metropolitan Statistical Area), or a borough of a city (such as Bronx or Brooklyn in New York
City).
• MustMatchPostalCode – Only candidates matching postal code are considered close. The
default is false.
• MustMatchInput – Only candidates matching all input preferences are considered close,
regardless of what is set for that particular preference. The default is false.
• FallbackToGeographic – Determines if a street geocode request which produces no
candidates, the geocode is performed at the centroid of a geographic region. The resulting point
is located at the geographic centroid of the area where it is possible to obtain the highest level of
accuracy. The default value is set to false.