Codebooks
- API Data came with no documentation, so had to create a codebook in order to proceed.
- See API codebook here: AC Real Estate Assessment Codebook
- Each variable profiled for quality (completeness, validity, consistency, and uniqueness). This is documented in the codebook.
- Following the profiling of the API data, data CDs were received from the county (one for each year form 2009 to 2013).
- See Year data here: Data Dictionary County Real Estate .
- Using the variables chosen from the API data, similar tables were constructed from the database to ensure direct comparability. The key variables were profiled for quality (completeness, validity, consistency, and uniqueness)—See
below.
Data Description
The tables below show the overall description of the various data tables used for this study. The information provided here was conducted on the original data before any data preparation. Data that is marked with "API" or 2015 came from the API and are current as of when they were pulled (July 1, 2015).
| Property: Basics information. such as primary address, owners, etc., about all parcels (identified by RealEstatePropertyCode) | ||
|---|---|---|
| Year | N | Unit of Analysis |
| 2009 | 64,827 | Active Properties |
| 2010 | 65,201 | Active Properties |
| 2011 | 65,242 | Active Properties |
| 2012 | 65,364 | Active Properties |
| 2013 | 65,443 | Active Properties |
| 2015 | 68,949 | Properties (Active or Inactive) |
|
Improvement Dwelling: Information, such as year built and heating type, about each dwelling on a parcel (identified by RealEstatePropertyCode) |
||
|---|---|---|
| Year | N | Unit of Analysis |
| 2009 | 62,081 | Dwelling |
| 2010 | 62,091 | Dwelling |
| 2011 | 62,265 | Dwelling |
| 2012 | 62,400 | Dwelling |
| 2013 | 62,478 | Dwelling |
| 2015 | 60,730 | Dwelling |
** Note: Each property (defined by RPC - RealEstatePropertyCode) can have one or more dwellings (typically 1). Dwellings are uniquely identified by the DwellingKey or a combination of RPC and ExtensionNbr.
|
Improvement Interior: Information about the interior of a dwelling, such as number of bedrooms or bathrooms, on a parcel (identified by RealEstatePropertyCode) |
||
|---|---|---|
| Year | N | Unit of Analysis |
| 2009 | 62,081 | Dwelling |
| 2010 | 62,091 | Dwelling |
| 2011 | 62,265 | Dwelling |
| 2012 | 62,400 | Dwelling |
| 2013 | 62,478 | Dwelling |
| 2015 | 134,698 | Each floor of a dwelling* |
** Note: For 2015, t he key is FloorKey or a combination of RealEstatePropertyCode, DwellingKey, ExtensionNbr, FloorNbr (this can have values like B for basement and 2.5 for a second floor with sloped ceiling).
| Assessment History (FROM DATA CDs) | ||
|---|---|---|
| Year | N | Unit of Analysis |
| 2009 | 324,966 | Assessment history up to 2013 for a parcel (One a year) |
| 2010 | 317,535 | Assessment history up to 2013 for a parcel (One a year) |
| 2011 | 321,547 | Assessment history up to 2013 for a parcel (One a year) |
| 2012 | 323,734 | Assessment history up to 2013 for a parcel (One a year) |
| 2013 | 324,966 | Assessment history up to 2013 for a parcel (One a year) |
| API Data * | |||
|---|---|---|---|
|
Table |
N |
Years |
Unit of Observation |
|
Assessment |
410,570 |
2009 - 2015 |
Assessment event for a parcel |
|
Assessment Payment History |
1,635,898 |
2009 - 2015 |
Tax event for a parcel |
|
Sales History |
42,552 |
2009 - 2015 |
Transaction where ownership changed for a parcel |
** Past Years are available off the API, but only profiled here those for the time period of interest
Data Quality
The tables below contain the results of the data profiling of key variables for the the following tables (click to jump to that section):
Note: "Real.Estate.Property.Code" is the property Code (parcel) for the Property assessed. "Master. Real.Estate.Property.Code" is specific for condo and primarily used for GIS
| Quality: Property 2009 | ||||
|---|---|---|---|---|
| Duplications | No duplicated rows | |||
| "realEstatePropertyCode" | No duplications | |||
| "masterRealEstatePropertyCode” | No duplications | |||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"propertyClassTypeDsc” |
100% | 100% | 56 levels | 100% |
|
"propertyStreetNbr” |
100% | 4% listed as 0 | 100% | |
|
"propertyStreetNbrSuffixCode” |
Levels coded with spaces |
Levels: " F " " G " " H " " I " " J " " K " "A " "B " "BK " "C " "D " "E " "F " "G " "H " "I " "J " "K " "L " "S " |
NA coding: " ", " " |
|
| "propertyStreetDirectionPrefixCode | Levels coded with spaces |
Levels: "N " "S " |
NA Coding: " " | |
|
"propertyStreetName” |
100% | Levels coded with spaces | Inconsistent coding in regards to suffix, eg: TH, th | |
|
"propertyStreetTypeCode” |
100% | Levels coded with spaces |
Levels: "AVE " "BLVD" "CIR " "CT " "DR " "HWY " "LN " "PIKE" "PKWY" "PL " "RD " "ST " "TER " |
100% |
|
"propertyStreetDirectionSuffixCode" |
Levels coded with spaces |
Levels: "N " "S " |
NA coding: NA, “ ” |
|
| "propertyUnitNbr" |
Levels coded with spaces Some unit numbers are proceeded with 4 "0000" |
6,371 levels | NA coding: " ", " " | |
|
"propertyCityName” |
100% | 100% | 100% | 100% |
|
"propertyZipCode” |
100% |
100% |
Levels: "22101" "22201" "22202" "22203" "22204" "22205" "22206" "22207" "22209" "22211" "22213" | 100% |
|
"propertyYearBuilt” |
5% missing |
1% are invalid entries: 0 and 1000 |
100% | |
|
"numberOfUnitsCnt” |
95% | Invalid "0" (4%) |
100% |
|
| Quality: Property 2010 | ||||
|---|---|---|---|---|
| Duplications | No duplicated rows | |||
| "realEstatePropertyCode" | No duplications | |||
| "masterRealEstatePropertyCode” | No duplications | |||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"propertyClassTypeDsc” |
100% | 100% | 56 levels | 100% |
|
"propertyStreetNbr” |
100% | 4% listed as 0 | 100% | |
|
"propertyStreetNbrSuffixCode” |
Levels coded with spaces |
Levels: " F " " G " " H " " I " " J " " K " "A " "B " "BK " "C " "D " "E " "F " "G " "H " "I " "J " "K " "L " "S " |
NA coding: " ", " " |
|
| "propertyStreetDirectionPrefixCode | Levels coded with spaces |
Levels: "N " "S " |
NA Coding: " " | |
|
"propertyStreetName” |
100% | Levels coded with spaces | Inconsistent coding in regards to suffix, eg: TH, th | |
|
"propertyStreetTypeCode” |
100% | Levels coded with spaces |
Levels: "AVE " "BLVD" "CIR " "CT " "DR " "HWY " "LN " "PIKE" "PKWY" "PL " "RD " "ST " "TER " |
100% |
|
"propertyStreetDirectionSuffixCode" |
Levels coded with spaces |
Levels: "N " "S " |
NA coding: NA, “ ” |
|
| "propertyUnitNbr" |
Levels coded with spaces Some unit numbers are proceeded with 4 "0000" |
6,412 levels | NA coding: " ", " " | |
|
"propertyCityName” |
100% | 100% | 100% | 100% |
|
"propertyZipCode” |
100% |
Some are outside of Arlington |
Levels: "22101" "22201" "22202" "22203" "22204" "22205" "22206" "22207" "22208" "22209" "22211" "22213" | 100% |
|
"propertyYearBuilt” |
5% missing |
1% are invalid entries: 0 and 1000 |
100% | |
|
"numberOfUnitsCnt” |
95% | Invalid "0" (4%) |
100% |
|
| Quality: Property 2011 | ||||
|---|---|---|---|---|
| Duplications | No duplicated rows | |||
| "realEstatePropertyCode" | No duplications | |||
| "masterRealEstatePropertyCode” | No duplications | |||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"propertyClassTypeDsc” |
100% | 100% | 56 levels | 100% |
|
"propertyStreetNbr” |
5 missing | 4% listed as 0 | 100% | |
|
"propertyStreetNbrSuffixCode” |
Levels coded with spaces |
Levels: " F " " G " " H " " I " " J " " K " "A " "B " "BK " "C " "D " "E " "F " "G " "H " "I " "J " "K " "L " "S " |
NA coding: " ", " " |
|
| "propertyStreetDirectionPrefixCode | Levels coded with spaces |
Levels: "N " "S " |
NA Coding: " " | |
|
"propertyStreetName” |
5 missing | Levels coded with spaces | Inconsistent coding in regards to suffix, eg: TH, th | |
|
"propertyStreetTypeCode” |
5 missing | Levels coded with spaces |
Levels: "AVE " "BLVD" "CIR " "CT " "DR " "HWY " "LN " "PIKE" "PKWY" "PL " "RD " "ST " "TER " |
100% |
|
"propertyStreetDirectionSuffixCode" |
Levels coded with spaces |
Levels: "N " "S " |
NA coding: NA, “ ” |
|
| "propertyUnitNbr" |
Levels coded with spaces Some unit numbers are proceeded with 4 "0000" |
6,419 levels | NA coding: " ", " " | |
|
"propertyCityName” |
100% | 100% | 100% | 100% |
|
"propertyZipCode” |
5 missing |
Some are outside of Arlington |
Levels: "22101" "22201" "22202" "22203" "22204" "22205" "22206" "22207" "22208" "22209" "22211" "22213" | 100% |
|
"propertyYearBuilt” |
5% missing |
1% are invalid entries: 0 and 1000 |
100% | |
|
"numberOfUnitsCnt” |
95% | Invalid "0" (4%) |
100% |
|
| Quality: Property 2012 | ||||
|---|---|---|---|---|
| Duplications | No duplicated rows | |||
| "realEstatePropertyCode" | No duplications | |||
| "masterRealEstatePropertyCode” | No duplications | |||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"propertyClassTypeDsc” |
100% | 100% | 56 levels | 100% |
|
"propertyStreetNbr” |
100% | 4% listed as 0 | 100% | |
|
"propertyStreetNbrSuffixCode” |
Levels coded with spaces |
Levels: " F " " G " " H " " I " " J " " K " "A " "B " "BK " "C " "D " "E " "F " "G " "H " "I " "J " "K " "L " "S " |
NA coding: " ", " " |
|
| "propertyStreetDirectionPrefixCode | Levels coded with spaces |
Levels: "N " "S " |
NA Coding: " " | |
|
"propertyStreetName” |
100% | Levels coded with spaces | Inconsistent coding in regards to suffix, eg: TH, th | |
|
"propertyStreetTypeCode” |
100% | Levels coded with spaces |
Levels:"AVE " "BLVD" "CIR " "CT " "DR " "HWY " "LN " "PIKE" "PKWY" "PL " "RD " "ST " "TER " |
100% |
|
"propertyStreetDirectionSuffixCode" |
Levels coded with spaces |
Levels: "N " "S " |
NA coding: NA, “ ” |
|
| "propertyUnitNbr" |
Levels coded with spaces Some unit numbers are proceeded with 4 "0000" |
6,487 levels | NA coding: " ", " " | |
|
"propertyCityName” |
100% | 100% | 100% | 100% |
|
"propertyZipCode” |
100% |
Some are outside of Arlington |
Levels: "20003" "22003" "22004" "22101" "22201" "22202" "22203" "22204" "22205" "22206" "22207" "22208" "22209" "22211" "22213" | 100% |
|
"propertyYearBuilt” |
5% missing |
1% are invalid entries: 0 and 1000 |
100% | |
|
"numberOfUnitsCnt” |
95% | Invalid "0" (4%) |
100% |
|
| Quality: Property 2013 | ||||
|---|---|---|---|---|
| Duplications | No duplicated rows | |||
| "realEstatePropertyCode" | No duplications | |||
| "masterRealEstatePropertyCode” | No duplications | |||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"propertyClassTypeDsc” |
100% | 100% | 55 levels | 100% |
|
"propertyStreetNbr” |
5 missing | 4% listed as 0 | 100% | |
|
"propertyStreetNbrSuffixCode” |
Levels coded with spaces |
Levels: " F " " G " " H " " I " " J " " K " "A " "B " "BK " "C " "D " "E " "F " "G " "H " "I " "J " "K " "L " "S " |
NA coding: " ", " ", NA |
|
| "propertyStreetDirectionPrefixCode | Levels coded with spaces |
Levels: "N " "S " |
NA Coding: " " | |
|
"propertyStreetName” |
5 missing | Levels coded with spaces | Inconsistent coding in regards to suffix, eg: TH, th | |
|
"propertyStreetTypeCode” |
5 missing | Levels coded with spaces |
Levels:"AVE " "BLVD" "CIR " "CT " "DR " "HWY " "LN " "PIKE" "PKWY" "PL " "RD " "ST " "TER " |
100% |
|
"propertyStreetDirectionSuffixCode" |
Levels coded with spaces |
Levels: "N " "S " |
NA coding: NA, “ ” |
|
| "propertyUnitNbr" |
Levels coded with spaces Some unit numbers are proceeded with 4 "0000" |
6,490 levels | NA coding: " ", " " | |
|
"propertyCityName” |
5 missing | 100% | 100% | 100% |
|
"propertyZipCode” |
5 missing |
Some are outside of Arlington Levels with spaces |
Levels: "20003 " "20011 " "22003 " "22004 " "22101 " "22201 " "22202 " "22203 " "22204 " "22205 " "22206 " "22207 " "22208 " "22209 " "22211 " "22213 " "2224 " "222O2 " | 100% |
|
"propertyYearBuilt” |
5% missing |
1% are invalid entries: 0 and 1000 |
100% | |
|
"numberOfUnitsCnt” |
99% missing |
Invalid "0" (9) Invalid greater than 2,000 (9) |
100% |
|
| Quality: Property 2015 *** | ||||
|---|---|---|---|---|
| Duplications | No duplicated rows | |||
| "realEstatePropertyCode" | No duplications | |||
| "masterRealEstatePropertyCode” | No duplications | |||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"reasPropertyStatusCode” |
100% | 100% |
Levels: "A", "T" Active/Inactive |
100% |
|
"propertyClassTypeDsc” |
100% | 100% | 58 levels | 100% |
|
"propertyStreetNbr” |
6% are missing | 100% | 100% | |
|
"propertyStreetNbrSuffixCode” |
100% |
Levels: "A" "B" "BK" "C" "D" "E" "F" "G" "H" "I" "J" "K" "L" "N" "S" |
100% | |
| "propertyStreetDirectionPrefixCode | 100% |
Levels: “N”, “S” |
100% | |
|
"propertyStreetName” |
753 missing | 100% | Inconsistent coding: 12th, 12TH, 19th, 19TH, 20th, 20TH,8th, 8TH | |
|
"propertyStreetTypeCode” |
753 missing | 100% |
Levels: "AVE","BLVD","CIR", "CT" ,"DR" , "HWY", "LN", "PIKE”, "PKWY", "PL", "RD", "ST", "TER" |
100% |
|
"propertyStreetDirectionSuffixCode" |
100% |
Levels: “N ”, “S ” |
NA coding: NA, “ ” |
|
| "propertyUnitNbr" | 100% | 6,501 levels | 100% | |
|
"propertyCityName” |
753 missing | “Clarendon" | 100% in Arlington | Multiple Spellings of Arlington |
|
"propertyZipCode” |
754 missing |
Zip codes out of Arlington or invalid |
Levels: "12201" "20003" "20009" "20011" "22003" "22004" "2207" "22101" "222004" "22201" "22202" "22203" "22204" "22205" "22206" "22207" "22208" "22209" "2221" "22211" "22213" "2224" "222O2" "970000" | 100% |
|
"propertyYearBuilt” |
9% missing |
Invalid years: “0”, “1000” |
100% | |
|
"numberOfUnitsCnt” |
Invalid "0" (9) |
100% |
||
*** No time stamp
| Improvement Dwelling 2009 | ||||
|---|---|---|---|---|
| Duplications | No duplicated rows | |||
| "realEstatePropertyCode” |
35 properties appear more than one |
|||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"heatingTypeDsc” |
43% missing | 100% | 23 different levels | 100% |
|
dwellingYearBuiltDate” |
100% |
5% listed as 0 or 1000 |
100% | |
| Improvement Dwelling 2010 | ||||
|---|---|---|---|---|
| Duplications | No duplicated rows | |||
| "realEstatePropertyCode” |
25 properties appear more than one |
|||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"heatingTypeDsc” |
43% missing | 100% | 22 different levels | 100% |
|
dwellingYearBuiltDate” |
100% |
4% listed as 0 or 1000 |
100% | |
| Improvement Dwelling 2011 | ||||
|---|---|---|---|---|
| Duplications | No duplicated rows | |||
| "realEstatePropertyCode” |
47 properties appear more than one |
|||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"heatingTypeDsc” |
43% missing | 100% | 23 different levels | 100% |
|
dwellingYearBuiltDate” |
100% |
4% listed as 0 or 1000 |
100% | |
| Improvement Dwelling 2012 | ||||
|---|---|---|---|---|
| Duplications | No duplicated rows | |||
| "realEstatePropertyCode” |
57 properties appear more than one |
|||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"heatingTypeDsc” |
43% missing | 100% | 23 different levels | 100% |
|
dwellingYearBuiltDate” |
100% |
4% listed as 0 or 1000 |
100% | |
| Improvement Dwelling 2013 | ||||
|---|---|---|---|---|
| Duplications | No duplicated rows | |||
| "realEstatePropertyCode” |
69 properties appear more than one |
|||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"heatingTypeDsc” |
43% missing | 100% | 24 different levels | 100% |
|
dwellingYearBuiltDate” |
100% |
4% listed as 0 or 1000 |
100% | |
| Improvement Dwelling 2015 *** | ||||
|---|---|---|---|---|
| Duplications | 66 are duplicated rows | |||
|
"realEstatePropertyCode” |
167 are duplications 160 properties appear more than once |
|||
| "dwellingKey" |
66 are duplications |
|||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"heatingTypeDsc” |
13 missing | 100% | 24 different levels | 100% |
|
dwellingYearBuiltDate” |
100% |
67 listed as 0 or 1000 |
100% | |
| "extensionNbr" | 100% |
|
levels: "R01" "R02" "R03" "R04" "R05" "R06" "R07" "R10" | 100% |
** No time stamp
| Improvement Interior 2009 | ||||
|---|---|---|---|---|
| Duplications |
No duplicated rows |
|||
|
"realEstatePropertyCode” |
25 of properties appear more than once |
|||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"bedroomCnt” |
100% | 100% | 100% | |
|
"FullBathroomCnt” |
100% | 100% | 100% | |
|
"HalfBathroomCnt" |
100% | 100% | 100% | |
| "Extension" | 100% | 100% | Levels: "R01" "R02" "R03" "R04" "R05" "R06" "R07" "R10" "VAC" | 100% |
| Improvement Interior 2010 | ||||
|---|---|---|---|---|
| Duplications |
No duplicated rows |
|||
| "realEstatePropertyCode” |
35 of properties appear more than once |
|||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"bedroomCnt” |
100% | 100% | 100% | |
|
"FullBathroomCnt” |
100% | 100% | 100% | |
|
"HalfBathroomCnt" |
100% | 100% | 100% | |
| "Extension" | 100% | 100% | Levels: "R01" "R02" "R03" "R04" "R05" "R06" "R07" "R10" "VAC" | 100% |
| Improvement Interior 2011 | ||||
|---|---|---|---|---|
| Duplications |
No duplicated rows |
|||
| "realEstatePropertyCode” |
47 of properties appear more than once |
|||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"bedroomCnt” |
100% | 100% | 100% | |
|
"FullBathroomCnt” |
100% | 100% | 100% | |
|
"HalfBathroomCnt" |
100% | 100% | 100% | |
| "Extension" | 100% | 100% | Levels: "R01" "R02" "R03" "R04" "R05" "R06" "R07" "R10" "VAC" | 100% |
| Improvement Interior 2012 | ||||
|---|---|---|---|---|
| Duplications |
No duplicated rows |
|||
| "realEstatePropertyCode” |
57 of properties appear more than once |
|||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"bedroomCnt” |
100% | 100% | 100% | |
|
"FullBathroomCnt” |
100% | 100% | 100% | |
|
"HalfBathroomCnt" |
100% | 100% | 100% | |
| "Extension" | 100% | 100% | Levels: "R01" "R02" "R03" "R04" "R05" "R06" "R07" "R10" "VAC" | 100% |
| Improvement Interior 2013 | ||||
|---|---|---|---|---|
| Duplications |
No duplicated rows |
|||
| "realEstatePropertyCode” |
69 of properties appear more than once |
|||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"bedroomCnt” |
100% | 100% | 100% | |
|
"FullBathroomCnt” |
100% | 100% | 100% | |
|
"HalfBathroomCnt" |
100% | 100% | 100% | |
| "Extension" | 100% | 100% | Levels: "R01" "R02" "R03" "R04" "R05" "R06" "R07" "R10" "VAC" | 100% |
| Improvement Interior 2015 *** | ||||
|---|---|---|---|---|
| Duplications |
No duplicated rows |
|||
|
"realEstatePropertyCode” |
80% are duplicated 64% of properties appear more than once |
|||
| "floorKey" |
None are duplicated |
|||
| "dwellingKey |
55% are duplicated 64% of dwellings appear more than once |
|||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"bedroomCnt” |
100% | 100% | 100% | |
|
"twoFixtureBathroomCnt” |
100% | 100% | 100% | |
|
"threeFixtureBathroomCnt" |
100% | 100% | 100% | |
|
"fourFixtureBathroomCnt” |
100% | 100% | 100% | |
|
"fiveFixtureBathroomCnt” |
100% | 100% | 100% | |
|
"extensionNbr" |
100% | 100% | Levels: "R01" "R02" "R03" "R04" "R05" "R06" "R07" "R10" | 100% |
** No time stamp
| Assessments 2009 (Data CD) | ||||
|---|---|---|---|---|
| Duplications | None are duplicated | |||
| "Parcel_ID" |
205 appear once and the rest are appear multiple times |
|||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"Year_Assessed" |
100% | 100%
|
|
100% |
|
"Impr" |
100% | 100% | 5% list as 0 (no structure on land) | 100% |
|
"Land” |
100% | 100% | 1% list as 0 | 100% |
|
"Totl |
100% | 220 are listed as 0 | 100% | |
| Assessments 2010 (Data CD) | ||||
|---|---|---|---|---|
| Duplications | None are duplicated | |||
| "Parcel_ID" |
220 appear once and the rest are appear multiple times |
|||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"Year_Assessed" |
100% | 100%
|
|
100% |
|
"Impr" |
100% | 100% | 5% list as 0 (no structure on land) | 100% |
|
"Land” |
100% | 100% | 1% list as 0 | 100% |
|
"Totl |
100% | 212 are listed as 0 |
100% |
|
| Assessments 2011 (Data CD) | ||||
|---|---|---|---|---|
| Duplications | None are duplicated | |||
| "Parcel_ID" |
117 appear once and the rest are appear multiple times |
|||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"Year_Assessed" |
100% | 100%
|
|
100% |
|
"Impr" |
100% | 100% | 5% list as 0 (no structure on land) | 100% |
|
"Land” |
100% | 100% | 1% list as 0 | 100% |
|
"Totl |
100% | 167 are listed as 0 |
100% |
|
| Assessments 2012 (Data CD) | ||||
|---|---|---|---|---|
| Duplications | None are duplicated | |||
| "Parcel_ID" |
236 appear once and the rest are appear multiple times |
|||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"Year_Assessed" |
100% | 100%
|
|
100% |
|
"Impr" |
100% | 100% | 4% list as 0 (no structure on land) | 100% |
|
"Land” |
100% | 100% | 1% list as 0 | 100% |
|
"Totl |
100% | 173 are listed as 0 |
100% |
|
| Assessments 2013 (Data CD) | ||||
|---|---|---|---|---|
| Duplications | None are duplicated | |||
| "Parcel_ID" |
205 appear once and the rest are appear multiple times |
|||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"Year_Assessed" |
100% | 100%
|
|
100% |
|
"Impr" |
100% | 100% | 4% list as 0 (no structure on land) | 100% |
|
"Land” |
100% | 100% | 1% list as 0 | 100% |
|
"Totl |
100% | 220 are listed as 0 |
100% |
|
| Assessments (API) | ||||
|---|---|---|---|---|
| Duplications | 21% are duplicated rows | |||
| "Assessment.Key” | 21% are duplicated | |||
| "Real.Estate.Property.Code” |
83% are duplications 99% of the properties appear more than once |
|||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
"Assessment.Date" |
100% |
YYYY-01-01 for all years have high frequencies as compared to other days |
100% | |
|
"Improvement.Value.Amount" |
100% | 100% | 4% list as 0 (no structure on land) | 100% |
|
"Land.Value.Amount” |
100% | 100% | 1% list as 0 | 100% |
|
"Total.Value.Amount" |
100% | 331 are listed as 0 | 100% | |
| "Assessment.Change.Reason.Type.Dsc" | 199 are missing | 100% | Levels: "01- Annual", "02- Permit", "03- Board of Equalization" "04- Court Order", "05- Review" ,"09- New Construction" , "16- Tax to Exempt" ,"18- Exempt to Tax" | 100% |
| Assessment Payment History (API) | ||||
|---|---|---|---|---|
| Duplications |
354 are duplicated rows |
|||
| "realEstatePropertyCode” |
96% are duplicated 100% of properties appear more than once |
|||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
“taxDueDate” |
YYYY-06-15 and YYY-10-05 for all years have high frequencies as compared to other days | 100% | 100% | |
| “displayLabelTypeName” | 100% | 100% | "Adjustment", "Deferral", "Levy", "Payment", "Relief" | 100% |
| “totalAmt” | 100% | 100% | 1 equals 0 | 100% |
| Sales History (API) | ||||
|---|---|---|---|---|
| Duplications |
473 (1%) of rows duplicated |
|||
| "realEstatePropertyCode" |
36% are duplicated 36% properties are listed more than once |
|||
| Variables | Completeness | Validity | Uniqueness | Consistency |
|
“salesTypeDsc” |
41% missing | 100% | 26 levels | 100% |
|
“saleAmt” |
100% | 100% | 47% list at 0 | 100% |
|
“saleDate” |
100% |
100% | 100% | |
Across the Years Checks
Address
- 872 properties have at least one different address in 2009, 2010, 2011, 2013,and 2015
- 191 properties have at lest one different address in 2009, 2010, 2011, and 2013
Number of Units
- 206 properties change unit counts across the years
- 9 have differences in the 20,000+ range due to errors in year 2013 data
Heating Type
- 1,189 properties have at least one different heating type listed between 2009 to 2013.
Year Built
- No year built occurred after that year's data (i.e. Year Built of 2012 in 2009 data)
- 830 properties have at least 1 year built that is different than the rest between 2009, 2010, 2011, 2012, 2013, and 2015.
- 403 properties have at least 1 year built that is different than the rest between 2009, 2010, 2011, 2012, and 2013.
- Large difference may indicate a new construction where original building was demolished.
Note: These figures do not include the difference where the minimum value was 0 or 1,000.
Attachments:
Arlington County Real Estate Data Dictionary.docx (application/vnd.openxmlformats-officedocument.wordprocessingml.document)
DataDictionary-2015.pdf (application/pdf)
image2015-9-18 15:51:17.png (image/png)
image2015-9-18 16:14:19.png (image/png)
image2015-9-19 16:10:3.png (image/png)
YearBuiltDiff.png (image/png)
UnitDifference.png (image/png)