Attribution

Attribution

Spatial data attribution is integral to spatial data analysis, as it provides the context and information needed to make informed decisions. When working with spatial data, users need to understand the meaning and limitations of attribute data, perform data validation and quality checks, and use appropriate methods to extract meaningful insights from the combined geographic and attribute data.

Attribution (attribute data) refers to the non-spatial information or characteristics associated with geographic features in a spatial dataset. In geographic information systems (GIS) and spatial data analysis, these attributes provide context and additional information about the geographic features, allowing users to understand and analyse the data more comprehensively.

Here are some key points related to spatial data attribution:

• Attributes: Attributes are essentially the data fields or columns in a spatial dataset. They can include a wide range of information, such as names, numerical values, text descriptions, dates, and more, depending on the type of data and the purpose of the dataset.

• Examples: Examples of attributes in spatial data include square meterage of island captured, project used for contour generation, purpose or functions of buildings, or the name of gazetted geographical features e.g. capes, mountain peaks.

• Database Integration: Spatial data is stored in a database format, with the geographic features linked to their corresponding attribute data. This allows for efficient querying, analysis, and visualization.

• Query and Analysis: Spatial analysts and GIS professionals use attribute data via definition queries to answer questions and perform analyses. For example, assess the impact of environmental variables on an area, or identify patterns and trends in geographic data.

• Symbolization: Attribute data can be used to symbolize or represent geographic features in a way that visually conveys information. For instance, a map might use different colours to represent different land use categories, with a legend explaining the meaning of each colour.

• Joining and Relating Data: In GIS, attribute data can be joined or related to spatial data through common keys (e.g., PFI). This allows users to integrate data from various sources for analysis.

• Metadata: Metadata associated with attribute data provides information about the source, accuracy, update frequency, and other relevant details. It is essential for understanding the quality and context of the attribute information.

• Data Quality: Ensuring the quality and accuracy of attribute data is critical. Errors or inconsistencies in attribute data can lead to incorrect analyses and decision-making.

• Time Series Data: Some spatial datasets include attributes that change over time, such as historical records of land use, population growth, or temperature measurements. Time series analysis is essential in such cases.

Attribute information during Feature Capture

Attribute information plays a pivotal role during the process of capturing features. Although various attributes are recorded for features, as shown in individual feature classes further in the document, the following examples are particularly noteworthy, as they are automatically calculated as part of the feature capture process.

Persistent and Unique Feature Identifiers

All features have been allocated a persistent feature identifier (PFI) and a unique feature identifier UFI.

A Persistent Feature Identifier (PFI) is generated for each feature at the point of creation in the database. The value of the PFI will stay with the feature through all changes to the feature (both spatial and non-spatial) until the feature is retired.

A Unique Feature Identifier (UFI) is generated for each new feature at the point of creation in the database (at this point the PFI and UFI will be the same). The value of the UFI will stay with the feature through all changes to the feature (both spatial and non-spatial) unless the feature is split into multiple other parts. If the feature is split, the separate parts will retain the original PFI but new UFI’s will be generated for the split parts.

Example of the process of PFI and UFI automatic generation. 

First capture of feature, the PFI and UFI are automatically generated and are the same (see below).

On splitting, the PFI remains the same and two new UFI’s are automatically generated (see below).

The numbering sequence used for the identifier is based on the nested numbering sequence used on the individual datasets. The numbering sequence is 15 characters and comprises from the following:

• The first character determines the State the data is in:

• The next two characters determine the data theme. These follow the naming conventions and ordering as documented in the United Nations Global Fundamental Geospatial Data Themes:

• The following three characters represent the feature class within the data theme. The first feature class is assigned the value of 001.  For the other feature classes within the theme, the ordering is random so that other feature classes can be added or removed later without affecting the ordering.

• The last nine characters are incrementally generated in the numbering sequence starting at 000000001 for the first feature.

An example, when first captured, Moreton Bay for both PFI and UFI is 106006000000019

            1                      -           Queensland (State)

            06                     -           Geographical Names  (UN Geospatial Data Theme)

            006                   -           Bays (Feature Class)

            000000019        -           incrementally generated number

Created Date*

All features are tagged with a created date/time stamping. This information is recorded in the attributes of the feature. The date represents the date the feature was constructed/created or the date the feature loaded to the database.  It is not the date of the source data.

Last Edited Date*

This date is automatically recorded in the attributes of the feature displays the date of any changes to a feature, either spatially or non-spatially. This allows users to track when changes are made to a feature.   When data is initially loaded to the database or a new feature is created, the created and last edited dates will be the same.

*These fields are for internal purposes only.

Source data naming convention

It is crucial to ascertain the origin of spatial topographic data, whether in graphical or informational form, as this knowledge is fundamental to preserving the data's integrity. This information is recorded through attribution in the Attribute and Feature Source columns (see individual feature classes definitions below for further information).

The source data is derived from diverse and numerous channels, and due to its constantly expanding nature, providing a comprehensive list becomes impractical. Therefore, adherence to several general guidelines is recommended:  Examples of source information -

For information obtained from Orthorectified imagery or Satellite Imagery. (Platform, Resolution, Project) e.g.:

• Orthophotography_10cm_Port Douglas

• Orthophotography_20cm_Galilee Basin South

• ALOS Satellite Imagery_1pt5m_West Qld Ph 4

• Spot Satellite Imagery_2pt5m_Zone 55

• LiDAR_10cm_Brisbane

For information obtained from Topographic Mapping or Topographic Data (Owner, Scale, Project, or map number) e.g.:

• Qld_1:25000 Topographic Map_794525

• GA_1:100000 Topographic Map_8562

• GA_1:250000 Topographic Data_Reservoirs

• DIGO_1:50000 Topographic Data_89542

For information obtained from Cadastral Mapping or Cadastral Data (Owner, Scale, Project, or map number) e.g.:

• Qld_1:25000 Cadastral Map_794525

• GA_1:100000 Cadastral Map_8562

• Qld_4 Mile Cadastral Map_4m16

• Qld_Parish Map_Cressbrook,

• Qld_Survey Plan_M12542

For information obtained from government databases (Database) or other Government agency (Department) e.g.:

• Qld_Place Names Database

• Qld_Place Names Plan _QPN265

• Qld_Spatial Cadastral Database

• Qld_Dept Environment, Science and Innovation

• Qld_Dept of Justice and Attorney-General

For information obtained from website (Owner, point of truth) e.g.:

• Australia Post Website

• Brisbane City Council Website

• Surf Life Saving Australia Website

• Website URL (where applicable)