Geocoding linkage results

1. Linking individual
properties
New Kent County: CoreLogic &
County Tax Assessments

2. New Kent COUNTY data New Kent CORELOGIC data
Started with13,650
properties
12,690
properties
7,355 USPS addresses
8,919 TIDY geocoded
9,344 USPS addresses
12,359 CL geocoded
3,529 repeat addresses
(3,244 missing house #s)
3,309 repeat addresses
(3,036 missing house
#s)
Worked with10,121
properties
9,381
properties
Matched
8,960
properties
8,960
properties
Pass 1: Full address (pink)
Pass 2: Address w/o mode – CL
(green)
Pass 3: USPS Add (blue)
Pass 4: Address w/o mode - CTY
(green)
Missed
1,162
properties
421
properties
Pass 1: Full address (pink)
Pass 2: Address w/o mode – CL
(green)
Pass 3: USPS Add (blue)
Pass 4: Address w/o mode -
CTY (green)
Summary of Property Linkage Results

3. COUNTY CORELOGIC
Original set
Unmatchable
Matchable
13650
3,529 (25.8%)
10,121 (74.1%)
12690
3,309 (26.1%)
9,381 (73.9%)
Matched
Full Address
Partial Address
USPS Address
8,960
(65%/88%)
7,090
(51.9%/ 70.0%)
906
(6.6%/8.9%)
964
(7.1%/7.5%)
8,960
(70%/91%)
7,090
(55.8%/75.5%)
906
(7.1%/9.6%)
964
(7.5%/10.2%)
Missed 1,162
(8.4%/11.48%)
421
(3.3%/4.4%)
COUNT
Y
CORELOGI
C
MATCHED 65% 70%
MISSED 8.4% 3.3%
UNMATCHABL
E
25.8% 26.1%
COUNT
Y
CORELOGI
C
MATCHED 88% 91%
MISSED 11.4% 4.4%
Summary of Property Linkage Results

4. Examples of
Unsuccessful
Matches
Here you can see,
sometimes there are
potential matches, but
for unit # reasons,
matching these on
address alone may not
be appropriate.
New Kent COUNTY data New Kent CORELOGIC data
Mapping
Property
Linkage
Results

5. New Kent COUNTY data New Kent CORELOGIC data
Examples of
Ineligible
Properties
Here you can see,
sometimes there are
potential matches, but
for there is insufficient
information about
these properties to
ensure an appropriate
match.
Mapping
Property
Linkage
Results

6. Successful Matches
◼︎ Full Address
◼︎ USPS Address
◼︎ Partial Address
Mapping
Property
Linkage
Results

7. Unsuccessful Matches
◼︎ County
◼︎ CoreLogic
Mapping
Property
Linkage
Results

8. Mapping
Property
Linkage
Results
Properties
ineligible
for matching
◼︎ County
◼︎ CoreLogic
Note: Geocoding of all
county data was not
possible without house
number. Many ineligible
county properties are
not pictured for that
reason.

9. Properties
ineligible
for matching
(with a house #)
◼︎ County
◼︎ CoreLogic
Note: Geocoding of all
county data was not
possible without house
number. Some ineligible
county properties are
not pictured for that
reason.
Mapping
Property
Linkage
Results

10. Why didn’t properties match?
• Ineligible Matches
• 3K from both datasets
• Houses without house numbers –
majority
• 285/273 either dataset with house
numbers
• Investigation could be done here
• However, if there are duplicated on address
string, don’t want incorrectly match units
and tie 2+ properties together
• Unsuccessful Matches
• 1K county, 400 CL
• Properties with unit designations
• Properties with West/North/South in one
but not the other
Why couldn’t we use
geocoding?
Issue #1
• Tidygeocoder seems to provide
coords at street level
• Corelogic coords seem to be on the
lot itself
Issue #2
• Tidygeocoder requires a city and
state
• New Kent county data does not
provide a city and state for the
property location (only the owner
location) – I used the owner location
city state to geocode, but some
lat/longs outside of the county and
even the country.

11. Appendix