DCAT-US 3.0: Temporal, Spatial, and Metrics

Temporal, Spatial, and Metrics

Supporting classes for time periods, locations, quality metrics, measurements, activities, and addresses.

Class PeriodOfTime #

Information about a specific time period with a start- and/or end-time

  • Type: combining
  • Additional properties: Any type allowed

Example:

{
    "@type": "PeriodOfTime",
    "startDate": "2024-01-01",
    "endDate": "2024-12-31"
}
Property Type Requirement Level Title/Description
endDate null or object Recommended The end date of the period of time
startDate null or object Recommended The start date of the period of time
@id string Optional  
@type string Optional  

Any of:

PeriodOfTime > anyOf > item 0 #

  • Type: object
  • Additional properties: Any type allowed

The following properties are required #

  • startDate

PeriodOfTime > anyOf > item 1 #

  • Type: object
  • Additional properties: Any type allowed

The following properties are required #

  • endDate

PeriodOfTime > endDate #

Requirement: Recommended

The end date of the period of time

  • Type: null or object

Examples:

"2024-12-31"

"2024-01-15T10:30:00Z"

"2024"

"2024-01"

PeriodOfTime > startDate #

Requirement: Recommended

The start date of the period of time

  • Type: null or object

Examples:

"2023-10-01"

"2024-01-15T10:30:00Z"

"2024"

"2024-01"

PeriodOfTime > @id #

Requirement: Optional

  • Type: string
  • Format: iri

Example:

"https://example.gov/periods/fiscal-year-2024"

PeriodOfTime > @type #

Requirement: Optional

  • Type: string
  • Default: "PeriodOfTime"

Class Location #

A named place or geographic area

  • Type: object
  • Additional properties: Any type allowed

Examples:

{
    "@type": "Location",
    "prefLabel": "Continental United States",
    "bbox": "POLYGON((-125 24, -66 24, -66 50, -125 50, -125 24))"
}

{
    "@type": "Location",
    "prefLabel": "Continental United States",
    "bbox": {
        "type": "Polygon",
        "coordinates": [
            [
                [
                    -77.119759,
                    38.791645
                ],
                [
                    -76.909393,
                    38.791645
                ],
                [
                    -76.909393,
                    38.99538
                ],
                [
                    -77.119759,
                    38.99538
                ],
                [
                    -77.119759,
                    38.791645
                ]
            ]
        ]
    }
}

{
    "@type": "Location",
    "prefLabel": "Null Island",
    "bbox": "POINT (0.0 0.0)"
}

{
    "@type": "Location",
    "prefLabel": "Random object",
    "geometry": {
        "type": "Polygon",
        "coordinates": [
            [
                [
                    -77.0402,
                    38.7916
                ],
                [
                    -76.9094,
                    38.8921
                ],
                [
                    -76.9115,
                    38.9355
                ],
                [
                    -76.9286,
                    38.9784
                ],
                [
                    -77.0024,
                    38.9657
                ],
                [
                    -77.0389,
                    38.9939
                ],
                [
                    -77.0672,
                    38.9687
                ],
                [
                    -77.0782,
                    38.9143
                ],
                [
                    -77.1198,
                    38.9342
                ],
                [
                    -77.1198,
                    38.8456
                ],
                [
                    -77.0402,
                    38.7916
                ]
            ]
        ]
    }
}
Property Type Requirement Level Title/Description
bbox More than one type Recommended Bounding box for the location, described in WKT, GeoJSON, or GML format
prefLabel null or string Recommended Preferred label or name of the Location
@id string Optional  
@type string Optional  
altLabel null or string Optional An alternative label or name for a location
centroid More than one type Optional The geographic center (centroid) of a location described in WKT, GeoJSON, or GML format
geometry More than one type Optional Associates a location with a corresponding geometry described in WKT, GeoJSON, or GML format
identifier null or Identifier Optional The unique geographic identifier for the Location, e.g., the URI or other unique identifier in the context of the relevant gazetteer
inScheme null or ConceptScheme Optional The gazetteer to which the location belongs
otherIdentifier null or array of Identifier classes Optional A list of geographic identifiers for the Location besides the main identifier, e.g. the URI or other unique identifiers in the context of the relevant gazetteer

Location > bbox #

Title: bounding box

Requirement: Recommended

Bounding box for the location, described in WKT, GeoJSON, or GML format

  • Type: combining
  • Additional properties: Any type allowed

Examples:

"POLYGON((-125 24, -66 24, -66 50, -125 50, -125 24))"

{
    "type": "Polygon",
    "coordinates": [
        [
            [
                -77.119759,
                38.791645
            ],
            [
                -76.909393,
                38.791645
            ],
            [
                -76.909393,
                38.99538
            ],
            [
                -77.119759,
                38.99538
            ],
            [
                -77.119759,
                38.791645
            ]
        ]
    ]
}

Any of:

Location > bbox > anyOf > item 0 #

  • Type: null

Location > bbox > anyOf > item 1 #

Bounding box represented in WKT, GeoJSON (stringified), or GML format

  • Type: string

Location > bbox > anyOf > item 2 #

Bounding box represented in GeoJSON format, either as a Polygon or in bbox array format

  • Type: object
  • Additional properties: Any type allowed
Property Type Requirement Level Title/Description
coordinates array Optional  
type const Optional  

Location > bbox > anyOf > item 2 > coordinates #

Requirement: Optional

  • Type: array
  • Required: Yes

Location > bbox > anyOf > item 2 > type #

Requirement: Optional

  • Type: const
  • Required: Yes

Specific value: "Polygon"

Location > prefLabel #

Title: geographic name

Requirement: Recommended

Preferred label or name of the Location

  • Type: null or string

Examples:

"Continental United States"

"Washington, D.C."

Location > @id #

Requirement: Optional

  • Type: string
  • Format: iri

Example:

"https://example.gov/locations/washington-dc"

Location > @type #

Requirement: Optional

  • Type: string
  • Default: "Location"

Location > altLabel #

Title: alternative name

Requirement: Optional

An alternative label or name for a location

  • Type: null or string

Example:

"DC"

Location > centroid #

Requirement: Optional

The geographic center (centroid) of a location described in WKT, GeoJSON, or GML format

  • Type: combining
  • Additional properties: Any type allowed

Example:

{
    "type": "Point",
    "coordinates": [
        -77.0369,
        38.9072
    ]
}

Any of:

Location > centroid > anyOf > item 0 #

  • Type: null

Location > centroid > anyOf > item 1 #

Center point represented in WKT, GeoJSON (stringified), or GML format

  • Type: string

Location > centroid > anyOf > item 2 #

Centroid represented in GeoJSON format; force point usage with coordinates of longitude and latitude

  • Type: object
  • Additional properties: Any type allowed
Property Type Requirement Level Title/Description
coordinates array of number Optional  
type const Optional  

Location > centroid > anyOf > item 2 > coordinates #

Requirement: Optional

  • Type: array of number
  • Required: Yes

Each item of this array must be:

Array Item #
  • Type: number

Location > centroid > anyOf > item 2 > type #

Requirement: Optional

  • Type: const
  • Required: Yes

Specific value: "Point"

Location > geometry #

Requirement: Optional

Associates a location with a corresponding geometry described in WKT, GeoJSON, or GML format

  • Type: combining
  • Additional properties: Any type allowed

Example:

{
    "type": "Polygon",
    "coordinates": [
        [
            [
                -77.0402,
                38.7916
            ],
            [
                -76.9094,
                38.8921
            ],
            [
                -76.9115,
                38.9355
            ],
            [
                -76.9286,
                38.9784
            ],
            [
                -77.0024,
                38.9657
            ],
            [
                -77.0389,
                38.9939
            ],
            [
                -77.0672,
                38.9687
            ],
            [
                -77.0782,
                38.9143
            ],
            [
                -77.1198,
                38.9342
            ],
            [
                -77.1198,
                38.8456
            ],
            [
                -77.0402,
                38.7916
            ]
        ]
    ]
}

Any of:

Location > geometry > anyOf > item 0 #

  • Type: null

Location > geometry > anyOf > item 1 #

String format of the full geometry of the location in WKT, GeoJSON, or GML format

  • Type: string

Location > geometry > anyOf > item 2 #

Geometry represented in GeoJSON format

  • Type: object
  • Additional properties: Any type allowed

The following properties are required #

  • type
  • coordinates

Location > identifier #

Requirement: Optional

The unique geographic identifier for the Location, e.g., the URI or other unique identifier in the context of the relevant gazetteer

Location > inScheme #

Title: gazetteer

Requirement: Optional

The gazetteer to which the location belongs

Location > otherIdentifier #

Requirement: Optional

A list of geographic identifiers for the Location besides the main identifier, e.g. the URI or other unique identifiers in the context of the relevant gazetteer

Each item of this array must be:

  • Identifier: A unique identifier and optionally it’s scheme and other relevant information

Class Metric #

A standard used to measure one aspect of data quality

  • Type: object
  • Additional properties: Any type allowed

Example:

{
    "@type": "Metric",
    "expectedDataType": "xsd:decimal",
    "inDimension": "https://example.gov/dimensions/completeness",
    "definition": "Percentage of non-null values in the dataset."
}
Property Type Requirement Level Title/Description
expectedDataType string Mandatory Represents the expected data type for the metric’s observed value (e.g., xsd:boolean, xsd:double etc…)
inDimension string Mandatory Represents the dimensions a quality metric, certificate and annotation allow a measurement of.
definition null or string Recommended Definition of the metric.
@id string Optional  
@type string Optional  

Metric > expectedDataType #

Requirement: Mandatory

Represents the expected data type for the metric’s observed value (e.g., xsd:boolean, xsd:double etc…)

  • Type: string
  • Required: Yes

Examples:

"xsd:decimal"

"xsd:double"

Metric > inDimension #

Requirement: Mandatory

Represents the dimensions a quality metric, certificate and annotation allow a measurement of.

  • Type: string
  • Required: Yes

Examples:

"https://example.gov/dimensions/completeness"

"https://www.w3.org/TR/vocab-dqv/#dqv:completeness"

Metric > definition #

Requirement: Recommended

Definition of the metric.

  • Type: null or string

Examples:

"Percentage of non-null values in the dataset."

"The percentage of non-null values for required fields in a dataset. A value of 1.0 indicates 100% completeness."

Metric > @id #

Requirement: Optional

  • Type: string
  • Format: iri

Example:

"https://example.gov/metrics/record-completeness"

Metric > @type #

Requirement: Optional

  • Type: string
  • Default: "Metric"

Class QualityMeasurement #

A measurement of a resource against a specific quality metric

  • Type: object
  • Additional properties: Any type allowed

Example:

{
    "@type": "QualityMeasurement",
    "isMeasurementOf": {
        "expectedDataType": "xsd:decimal",
        "inDimension": "https://example.gov/dimensions/completeness"
    },
    "value": "98.5",
    "unitMeasure": "percent"
}
Property Type Requirement Level Title/Description
isMeasurementOf object Mandatory The metric being observed
value string Mandatory The value computed by metric
@id string Optional  
@type string Optional  
unitMeasure null or string Optional Unit of measure associated with the value

QualityMeasurement > isMeasurementOf #

Requirement: Mandatory

The metric being observed

  • Type: object
  • Required: Yes
  • Additional properties: Any type allowed
  • Defined in: Metric

QualityMeasurement > value #

Requirement: Mandatory

The value computed by metric

  • Type: string
  • Required: Yes

Example:

"98.5"

QualityMeasurement > @id #

Requirement: Optional

  • Type: string
  • Format: iri

Example:

"https://example.gov/quality-measurements/completeness-001"

QualityMeasurement > @type #

Requirement: Optional

  • Type: string
  • Default: "QualityMeasurement"

QualityMeasurement > unitMeasure #

Title: unit of measure

Requirement: Optional

Unit of measure associated with the value

  • Type: null or string

Example:

"percent"

Class Activity #

An activity related to creating, changing, or using a resource

  • Type: object
  • Additional properties: Any type allowed

Example:

{
    "@type": "Activity",
    "label": "Data Collection",
    "category": [
        "https://example.gov/concepts/data-collection"
    ]
}
Property Type Requirement Level Title/Description
label string Mandatory A human-readable label for the activity
@id string Optional  
@type string Optional  
category null or array of Concept classes Optional List of categories for the Activity

Activity > label #

Requirement: Mandatory

A human-readable label for the activity

  • Type: string
  • Required: Yes

Examples:

"Data Collection"

"Data Processing and Quality Assurance"

Activity > @id #

Requirement: Optional

  • Type: string
  • Format: iri

Example:

"https://example.gov/activities/data-processing-001"

Activity > @type #

Requirement: Optional

  • Type: string
  • Default: "Activity"

Activity > category #

Requirement: Optional

List of categories for the Activity

  • Type: null or array of Concept classes

Each item of this array must be:

  • Concept: A controlled term or label, optionally drawn from a concept scheme

Class Address #

A single physical address

  • Type: object
  • Additional properties: Any type allowed

Example:

{
    "@type": "Address",
    "street-address": "151 Patton Avenue",
    "locality": "Asheville",
    "region": "NC",
    "postal-code": "28801",
    "country-name": "United States"
}
Property Type Requirement Level Title/Description
country-name null or string Recommended The country of the Address
locality null or string Recommended The city of the Address
postal-code null or string Recommended The postal code of the Address
region null or string Recommended The administrative area of the Address. Depending on the country, this corresponds to a province, a county, a region, or a state
street-address null or string Recommended The street name and civic number of an Address
@id string Optional  
@type string Optional  

Address > country-name #

Title: country

Requirement: Recommended

The country of the Address

  • Type: null or string

Example:

"United States"

Address > locality #

Requirement: Recommended

The city of the Address

  • Type: null or string

Examples:

"Asheville"

"Washington"

Address > postal-code #

Requirement: Recommended

The postal code of the Address

  • Type: null or string

Examples:

"28801"

"20230"

Address > region #

Title: administrative area

Requirement: Recommended

The administrative area of the Address. Depending on the country, this corresponds to a province, a county, a region, or a state

  • Type: null or string

Examples:

"NC"

"DC"

Address > street-address #

Requirement: Recommended

The street name and civic number of an Address

  • Type: null or string

Examples:

"151 Patton Avenue"

"1401 Constitution Ave NW"

Address > @id #

Requirement: Optional

  • Type: string
  • Format: iri

Example:

"https://example.gov/addresses/hq-001"

Address > @type #

Requirement: Optional

  • Type: string
  • Default: "Address"