Matching Options
Matching options let you set match restrictions, fallback, and multiple match settings so that the matching can be as strict or relaxed as you need. The strictest matching conditions require an exact match on house number, street name, postal code and no fallback to postal code centroids. The geocoder looks for an exact street address match within the postal code in the input address. Relaxing the conditions broadens the area in which it searches for a match. For example, by relaxing the postal code, the geocoder searches for candidates outside the postal code but within the city of your input address.
optionName |
Description |
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KeepMultimatch |
Specifies whether to return results when the address matches to multiple candidates in the database. If this option is not selected, an address that results in multiple candidates will fail to geocode. If you select this option, specify the maximum number of candidates to return using the MaxCandidates option (see below).
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MaxCandidates |
If you specify KeepMultimatch=Y, this option specifies the maximum number of results to return. The default is 1. Specify -1 (minus one) to return all possible candidates. |
ReturnRanges |
Specifies whether to return address range information. If you enable this option, the output field Ranges will be included in the output. A range is a series of addresses along a street segment. For example, 5400-5499 Main St. is an address range representing addresses in the 5400 block of Main St. A range may represent just odd or even addresses within a segment, or both odd and even addresses. A range may also represent a single building with multiple units, such as an apartment building.
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MaxRanges |
If you choose to return ranges, this option specifies the maximum number of ranges to return for each candidate. Since the geocoder returns one candidate per segment, and since a segment may contain multiple ranges, this option allows you to see the other ranges in a candidate's segment. |
MaxRangeUnits |
If you choose to return ranges, this option specifies the maximum number of units (for example, apartments or suites) to return for each range. For example, if you were to geocode an office building at 65 Main St. containing four suites, there would be a maximum of four units returned for the building's range (65 Suite 1, 65 Suite 2, 65 Suite 3, and 65 Suite 4. If you were to specify a maximum number of units as 2, then only two units would be returned instead of all four. |
CloseMatchesOnly |
Specifies whether to return only those geocoded results that are close match candidates. For example, if there are 10 candidates and two of them are close candidates, and you enable this option, only the two close matching candidates would be returned instead of all 10. To specify what is considered a close match, use the MustMatch options. Address candidates are ranked according to how closely the input address matches these preferences.
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MatchMode |
Specifies how to determine whether a candidate is a close match. One of the following:
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MustMatchInput |
Specifies whether candidates must match all non-blank input fields to be considered a close match. For example, if an input address contains a city and postal code, then candidates for this address must match the city and postal code to be considered a close match.
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MustMatchHouseNumber |
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MustMatchStreet |
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MustMatchLocality |
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MustMatchCity |
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MustMatchCounty |
Specifies whether candidates must match the county (or equivalent) to be considered a close match. The meaning of county varies for different countries. One of the following:
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MustMatchStateProvince |
Specifies whether candidates must match the state or province (or equivalent) to be considered a close match. One of the following:
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MustMatchPostalCode |
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SortCandidatesUsingLocale |
This is a Reverse geocoding option that applies to Greece, Russia, Ukraine, and any
other country that supports dual character sets (such as the Middle
East countries). Specifies whether candidates are sorted and returned based on the input language. That is, if the input was in Russian, the Russian character candidate is returned first followed by the English language candidate. This will override the dictionary order.
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You may want to use a balanced strategy between match rate and geographic precision. That is, you may want to geocode as many records as possible automatically, but at the same time want to minimize the number of weaker matches (false positives). For example, false positives can occur when the geocoder:
- finds a street that sounds like the input street.
- finds the same street in another city (if postal code match is not required).
- finds the street but with a different house number (if house number is not required).
The following settings may achieve a good balance between match rate and precision:
- CloseMatchesOnly—Specify "Y".
- MustMatchHouseNumber—Specify "Y".
- MustMatchStreet—Specify "Y".
- FallbackToPostal—Specify "N".