How it Works and What it Means
The S category indicate that the record was matched to a single address candidate from the Address Dictionary. The first character S indicates that MapMarker found a street address that matches your input address. The second position in the code reflects the positional accuracy of the resulting point for the geocoded record, as indicated below.
- S5 (Most Accurate) - single close match, point located at street address position
- S4 - single close match, point located at the center of shape point path
- S3 - single close match, point located at ZIP+4 centroid
- S2 - single close match, point located at ZIP+2 centroid
- S1 (Least Accurate) - single close match, point located at ZIP Code centroid
An S5 hit is the best geocode possible. This is an exact match
on Street number, Street name, City and Zip Code. When the Risk
Meter gets an S5 hit, the address is automatically passed through
the system. Tests can be carried out without any address verification
from the user.
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An S4 is the next best possible hit. An S4 is returned when the
address entered corresponds to a street that does not contain
address segments. The geocoder will place the point at the center
of the line segment. In the case illustrated above, imagine that
Main Street did not have any address segments and as a result,
it places the house at the center of road segment.
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An S3 is comparable in accuracy if not better than an S4. An
S3 is returned when the address entered can not be matched to
the street name or number, but can be matched to a Zip+4 Centroid.
A Zip+4 Centroid is the center point of a Zip+4 area which is
a USPS Standard for mail delivery. A Zip+4 could cover several
houses, a block, a building or a floor of a building.
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An S2 is returned when the geocoder can find only a Zip+2 Centroid.
In looking at the illustration above, we give a very simple imaginary
Zip Code with 100 Zip+2 Boundaries. Actual Zip Codes are not
square and Zip+2 boundaries do not fall into nice, neat, ordered
rows. Many Zip+2 boundaries are not contiguous and therefore
the georesult lacks the accuracy required to do a property look
up with a great degree of certainty. If this georesult is returned
the user will see the message: GeoCode (S2) Does not match Minimum
Criteria.
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An S1 is the least accurate of the georesult family. An S1 is
returned when the only part of the address that could be matched
is the Zip Code. As a result, the geocoder places the point at
the geographic center of the Zip. In the illustration above,
the S1 match looks pretty good, however, remember that the Zip
Code above is ficticious and the chances of the address you are
trying to geocode falling directly in the geographic center of
a Zip is highly improbable. If this georesult is returned the
user will see the message: GeoCode (S1) Does not match Minimum
Criteria.
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