Linking Open Government Data

Previous title: "LOGD Instance Hub URI Design: Unique URIs for LOGD instances"

URI Design Goals

These principles should produce:

• URIs that are easily re-hosted. This means that a generated should be easily transformed from one BASE URI-space (e.g. logd) to another, allowing easier buy-in from government agencies.
  • For example, the pattern http://logd.tw.rpi.edu/id/epa-gov/XXXXXX is easily (syntactically) transformed to http://epa.gov/id/XXXXXX when/if the EPA buys in to this scheme
• Concise URIs with as little "cruft" as possible
• URIs that span many domains including:
  • National identifiers (e.g. govermental agencies, states, zip codes)
  • State-level identifiers (e.g. counties, congressional districts)
  • Agency-level identifiers (e.g. EPA facilities)

URI Design Overview

URI Template: 'http://' BASE '/' 'id' '/' ORG '/' CATEGORY ( '/' TOKEN )+
For case of the TWC RPI Instance Hub BASE will be: logd.tw.rpi.edu

Notes

• id
  
  • This is required because we don't want to pollute the top namespace of BASE with identifiers.
  • Prefer id over instance-hub because we want as short a token as possible; the id token doesn't add any semantics, it's just a syntactic way of distinguishing these URIs from others.
  • Also, consistency with data.gov.uk URIs here is a good thing.
• ORG
  
  • This is a short token representing the agency, government, or organization that controls the identfier space.
  • For US identifiers, this token will start with us/, and be followed by a designation of either federal or state-level (e.g. us/fed, us/ny, us/ca).
  • Identifiers relating to data.gov will all fall under the federal us/fed' space.
  • For identifiers that aren't directly governmental, the ORG token should be suitably unique; for example, we use usps-com below for USPS controlled zip code URIs.
• CATEGORY and TOKEN
  
  • These are ORG-specific values that identify the specific instance.
  • Use as many TOKENs as necessary to distinguish the instance.

Example Identifiers

US Government Agencies

Owner

federal

Suggested

http://BASE/id/us/fed/agency/NAME/SUBNAME

Example

http://BASE/id/us/fed/agency/Commerce/National_Oceanic_and_Atmospheric_Administration

Example

http://BASE/id/us/fed/agency/Department_of_Health_and_Human_Services/Centers_for_Disease_Control

States and Territories

Owner

federal

Suggested

http://BASE/id/us/state/NAME

Example

http://logd.tw.rpi.edu/id/us/state/Vermont

Include

FIPS code, two-letter code, name, dbpedia/geonames/govtrack sameAs

Notes

States and territories are identified by FIPS 5-2 codes, two-letter abbreviations, and names. Not all states/territories have two-letter abbreviations. FIPS 5-2 has been withdrawn as a FIPS standard (2008). Names are probably the most stable.

Counties

Owner

federal

Suggested

http://BASE/id/us/state/STATE/COUNTY

Example

http://BASE/id/us/state/Alaska/Bethel_Census_Area

Notes

Just like states, counties are identified by FIPS codes (FIPS 6-4), but these have been withdrawn (2008). Names of counties seem stable, though two states don't refer to them as "counties": Alaska (borough) and Louisiana (parish). Hierarchy built on the state/territory URIs seems like the best design.

Zip codes

Owner

USPS

Suggested

http://BASE/id/usps-com/zip/CODE

Example

http://BASE/id/usps-com/zip/09510

Include

code, link to state

Notes

The Census Bureau uses ZIP Code Tabulation Areas (ZCTA) based on ZIP codes.

Congressional districts

Owner

state

Suggested

http://BASE/id/us/STATE/congressional-district/NUMBER

Example

http://BASE/id/us/ma/congressional-district/4

Include

link to state, dbpedia sameAs

Notes

STATE here can be a two-letter code because (at least for present-day districts and non-voting delegations) we only have data for places with two-letter codes: the the 50 states, DC, AS, GU, MP, PR, and VI.

EPA Facilities

Owner

EPA

Suggested

http://BASE/id/epa-gov/facility/ID

Example

http://BASE/id/epa-gov/facility/110007995027

Include

link to facility detail report, link to state: http://iaspub.epa.gov/enviro/fii_query_detail.disp_program_facility?p_registry_id=110007995027

Notes

EPA facility IDs are used in EPA Facilities Registry System (FRS) datasets (e.g. Dataset 1008)

References

[1] legislation.gov.uk URIs
[2] Creating Linked Data - Part II: Defining URIs
[3] The Real Deal: data.gov.uk

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