VT Census Case Studies : James City County: GIS/Mapping

Created and last modified by molfe on 02 Jan 2016

Brief Overall Description of the Dataset:

The GIS/Mapping Section of the Real Estate Assessment Division (Division) is responsible for GIS (Geographic Information System) functions and applications, which include mapping and the use of property information.

The activities of the GIS/Mapping Section include:

  • updates of cadastral and planimetric data;

  • production of GIS-produced maps;

  • updates and annual printing of the James City County Parcel Map Book; and

  • maintenance of the Property Information internet website

List of GIS resources, that include the surrounding area: http://www.jamescitycountyva.gov/assessments/gis-mapping-links.html

Link: http://www.jamescitycountyva.gov/assessments/gis-mapping.html

http://www.jamescitycountyva.gov/assessments/gis-mapping-layers.html

Date Inventory Completed: 8/12/2015

Screening

  • Is the data collected opinion-based?
  • Is the data collection recurring (must be collected at least annually)?
  • Is there data available for 2013?
  • Is the data collected at the property or housing unit level?
  • Can we access the data by August 15th?

Purpose

  • What is the purpose of the organization collecting the data?

The GIS Mapping Center serves as the County's official mapping and analysis unit providing GIS consulting services,  cartographic expertise, aerial photo analysis, data maintenance, and data conversion support for all County agencies.   

  • Why is it collected and how does the organization use it?

Data is primarily disseminated to County government offices 

  • Who else uses the data?

The data is used throughout the county in addition to researchers, citizens, and businesses

  • Who do they sell the data to?

Researchers, citizens, businesses

 

Method

  • What is the data collection method? 

Unknown

  • What is the type of data collected? 

Geo Coded data

  • If designed, who created the questions?

  • What is the raw source of the collected data (prior to any aggregation)? 

Unknown


Description

  • What is the general topic of the data (1-2 words)?

GIS Data

  • What are the earliest and latest dates for which data is available?

Unknown

  • Is data collected and available periodically?

Yes (unknown frequency)

  • How soon after a reference period ends can a data source be prepared and provided? 

Unknown


Selectivity

  • What is the universe (e.g., population) that the data represents?

James City County


Accessibility

  • How is the data accessed? 

Compressed files can be downloaded online

  • Is it open data?

Yes

  • Any legal, regulatory, or administrative restrictions on accessing the data source?

None stated

  • Cost? - One time or annual or project based payment?

Data on the website are free

For other data,cost varies depending on product. See: http://www.jamescitycountyva.gov/assessments/gis-mapping-price.html

Does this dataset appear to meet our needs for the Census study? YES

Full Inventory

Description

  • Features
    • What is the temporal nature of the data: longitudinal, time-series, or one time point?

Longitudinal

    • Geospatial? If Yes, at what level?

Varies: address, parcel,  census block/tract, and/or lat/long

Projection: NAD 1983 StatePlane Virginia South FIPS 4502 Feet

 

Metadata

  • Is there information available to assess the transparency and soundness of the methods to gather the data for our purposes?

No

  • Is there a description of each variable in the source along with their valid values?

See mata data: ftp://property.jamescitycountyva.gov/GIS/layers/GIS_Metadata.pdf

  • Are there unique IDs for unique elements that can be used for linking data?

Varies

  • Is there a data dictionary or codebook?

See meta data or map index of street names: http://www.jamescitycountyva.gov/pdf/realestate/Policies-all/streetlist.pdf


Selectivity

  • What unit is represented at the record level of the data source?

Varies

  • Does this universe match the stated intentions for the data collection? If not, what has been included or excluded and why?

Unknown

  • What is the sampling technique used (if applicable)? 

  • What was the coverage?

Unknown


Stability/Coherence

  • Were there any changes to the universe of data being captured (including geographical areas covered) and if so what were they?

Unknown

  • Were there any changes in the data capture method and if so what were they? 

Unknown

  • Were there any changes in the sources of data and if so what were they? 

Unknown


Accuracy

  • Any known sources of error?

“This data is neither legally recorded nor a survey and is not intended to be used as such. The information displayed is a compilation of records, information, and data obtained from various sources, and James City County is not responsible for its accuracy or how current it may be. If discrepancies are found, please contact the Real Estate Assessment Division of James City County, Mapping/GIS Section”

  • Describe any quality control checks performed by the data’s owner.

“James City County makes every reasonable effort to insure the accuracy of the data set. Within the urban areas of the county we strive to have a plus or minus 5 foot accuracy. Out in the rural areas, where sometimes we do not have any recently recorded plats, the accuracy could go higher to almost a plus or minus 20 feet.”

 

Accessibility

  • Any records or fields collected, but not included in data source, such as for confidentiality reasons)? 

Unknown

  • Is there a subset of variables and/or data that is must be obtained through a separate process? If yes, is there a separate legal, regulatory, or administrative restrictions on accessing the data source? Cost? - One time or annual or project based payment?

Unknown


Privacy and security

  • Was consent given by participant? If so, how was consent given?

Public data

  • Are there legal limitations or restrictions on the use of the data? 

“Although these data have been processed successfully on a computer system at James City County, no warranty expressed or implied is made by James City County regarding the utility of the data on any other system, nor shall the act of distribution constitute any such warranty. No responsibility is assumed by James City County in the use of these data.”

  • What confidentiality policies does the source have? 

None stated

 

Research

  • What research has been done with this dataset? (e.g., impact of policies, predictors of student success)

None stated

  • Include any links to research if provided:
  • List any other data use notes provided by the supplier.

Gaps/Concerns

  • Feasibility - can all jurisdiction levels provide the data (if applicable)?
  • Data ownership - a lack of clarity in legal guidance stemming from a lack of clarity with who owns digital data?
  • Data collection authority - what data is reasonably private and what constitutes unwarranted intrusion?
  • Describe any other notes you have or any gaps/concerns you see with this dataset: