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
@id string Optional  
@type string Optional  
endDate More than one type Recommended The end date of the period of time
startDate More than one type Recommended The start date of the period of time
Any of
item 0
item 1

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 > @id #

Requirement: Optional

Type string
Format iri

Example:

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

PeriodOfTime > @type #

Requirement: Optional

Type string
Default "PeriodOfTime"

PeriodOfTime > endDate #

Requirement: Recommended

The end date of the period of time

Type combining
Additional properties Any type allowed

Examples:

"2024-12-31"

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

"2024"

"2024-01"
Any of
Null allowed when not required
item 1

PeriodOfTime > endDate > anyOf > Null allowed when not required #

| Type | null | | ——– | —— |

PeriodOfTime > endDate > anyOf > item 1 #

Type combining
Additional properties Any type allowed
Any of
item 0
item 1
item 2
item 3

PeriodOfTime > endDate > anyOf > item 1 > anyOf > item 0 #

Type string
Format date-time

PeriodOfTime > endDate > anyOf > item 1 > anyOf > item 1 #

Type string
Format date

PeriodOfTime > endDate > anyOf > item 1 > anyOf > item 2 #

A year in YYYY format

| Type | string | | ——– | ——– |

Restrictions  
Must match regular expression ^[0-9]{4}$ Test

PeriodOfTime > endDate > anyOf > item 1 > anyOf > item 3 #

A year and month in YYYY-MM format

| Type | string | | ——– | ——– |

Restrictions  
Must match regular expression ^[0-9]{4}-[0-9]{2}$ Test

PeriodOfTime > startDate #

Requirement: Recommended

The start date of the period of time

Type combining
Additional properties Any type allowed

Examples:

"2023-10-01"

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

"2024"

"2024-01"
Any of
Null allowed when not required
item 1

PeriodOfTime > startDate > anyOf > Null allowed when not required #

| Type | null | | ——– | —— |

PeriodOfTime > startDate > anyOf > item 1 #

Type combining
Additional properties Any type allowed
Any of
item 0
item 1
item 2
item 3

PeriodOfTime > startDate > anyOf > item 1 > anyOf > item 0 #

Type string
Format date-time

PeriodOfTime > startDate > anyOf > item 1 > anyOf > item 1 #

Type string
Format date

PeriodOfTime > startDate > anyOf > item 1 > anyOf > item 2 #

A year in YYYY format

| Type | string | | ——– | ——– |

Restrictions  
Must match regular expression ^[0-9]{4}$ Test

PeriodOfTime > startDate > anyOf > item 1 > anyOf > item 3 #

A year and month in YYYY-MM format

| Type | string | | ——– | ——– |

Restrictions  
Must match regular expression ^[0-9]{4}-[0-9]{2}$ Test

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
@id string Optional  
@type string Optional  
bbox More than one type Recommended Bounding box for the location, described in WKT, GeoJSON, or GML format
centroid More than one type Optional The geographic center (centroid) of a location described in WKT, GeoJSON, or GML format
identifier More than one type Optional The unique geographic identifier for the Location, e.g., the URI or other unique identifier in the context of the relevant gazetteer
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
geometry More than one type Optional Associates a location with a corresponding geometry described in WKT, GeoJSON, or GML format
inScheme More than one type Optional The gazetteer to which the location belongs
altLabel null or string Optional An alternative label or name for a location
prefLabel null or string Recommended Preferred label or name of the Location

Location > @id #

Requirement: Optional

Type string
Format iri

Example:

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

Location > @type #

Requirement: Optional

Type string
Default "Location"

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
item 0
item 1
item 2

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 > 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
item 0
item 1
item 2

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 Description
coordinates items -
Array Item #

| Type | number | | ——– | ——– |

Location > centroid > anyOf > item 2 > type #

Requirement: Optional

Type const
Required Yes

Specific value: "Point"

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

Type combining
Additional properties Any type allowed
Any of
item 0
Identifier

Location > identifier > anyOf > item 0 #

| Type | null | | ——– | —— |

Location > identifier > anyOf > Identifier #

inline description of Identifier

Type combining
Additional properties Any type allowed
Defined in Identifier

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

| Type | null or array of Identifier classes | | ——– | ———————————————————————————— |

Each item of this array must be Description
Identifier A unique identifier and optionally it’s scheme and other relevant information

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
item 0
item 1
item 2

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 > inScheme #

Title: gazetteer

Requirement: Optional

The gazetteer to which the location belongs

Type combining
Additional properties Any type allowed
Any of
item 0
ConceptScheme

Location > inScheme > anyOf > item 0 #

| Type | null | | ——– | —— |

Location > inScheme > anyOf > ConceptScheme #

inline description of the gazetteer

Type object
Additional properties Any type allowed
Defined in ConceptScheme

Location > altLabel #

Title: alternative name

Requirement: Optional

An alternative label or name for a location

| Type | null or string | | ——– | —————- |

Example:

"DC"

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."

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
@id string Optional  
@type string Optional  
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.

Metric > @id #

Requirement: Optional

Type string
Format iri

Example:

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

Metric > @type #

Requirement: Optional

Type string
Default "Metric"

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."

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
@id string Optional  
@type string Optional  
isMeasurementOf object Mandatory The metric being observed
value string Mandatory The value computed by metric
unitMeasure null or string Optional Unit of measure associated with the value

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 > 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 > 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
@id string Optional  
@type string Optional  
category null or array of Concept classes Optional List of categories for the Activity
label string Mandatory A human-readable label for the activity

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

Activity > label #

Requirement: Mandatory

A human-readable label for the activity

Type string
Required Yes

Examples:

"Data Collection"

"Data Processing and Quality Assurance"

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
@id string Optional  
@type string Optional  
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

Address > @id #

Requirement: Optional

Type string
Format iri

Example:

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

Address > @type #

Requirement: Optional

Type string
Default "Address"

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"