Spatial Hierarchy applied to National Spatial Data Infrastructure

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Spatial Hierarchy applied to National Spatial
Data Infrastructure

• Francisco Escobar
• Serryn Eagleson
• Department of Geomatics
• The University of Melbourne

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Outline

• Background
• NSDI
• Hierarchical Spatial Reasoning
• The problem uncovered
• Methods to solve the problem
• SHR - Applied to Administrative Boundaries
• Conclusion

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Background

• GIS for General Practice project
• Small ARC The Impact of Spatial Hierarchical
  Structures in the Diffusion of Geographic
  Information Systems (GIS)
• SPIRT ARC Developing National Spatial Data
  Infrastructures to Implement Sustainable
  Development

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NSDI

• Definition
• Trends
• Issues
• Components
• Spatial hierarchy and NSDIs

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Spatial Hierarchy Reasoning

• Hierarchical Spatial Reasoning (HSR)as research
  approach / methodto design models for complex
  spatial concepts using hierarchy as the main
  organizing principle

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Hierarchy definition

• Russian doll Babushka
• Quad trees
• Tree-like structure of a system which can be
  subdivided in smaller subsystems, which in turn
  can be subdivided in smaller subsystems, etc
  (Koestler, 1968)

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Hierarchy properties

• Part-Whole
• Janus effect
• Near Decomposability

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Spatial Hierarchy Reasoning (cont)

• Research Approach
• Space has rich, complex nature gt Need for
  abstraction mechanisms gt Hierarchisation
• Research in Spatial Information Theory focuses on
  conceptualization of space, in particular
  conceptual hierarchisation of space and spatial
  phenomena.

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The problem uncovered
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A model for the future
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Spatial Hierarchy and Administration Boundaries

• Throughout history boundaries have been used to
  divide the space around us into smaller units
• In the majority of cases these boundaries have
  been established to facilitate administration,
  political and economic purposes

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Examples of different spatial boundaries in
Victoria

• Cadastre - Ownership facilitate Land Market
• Collection district - Collection of ABS
  Statistics
• Postcode - Facilitate mail Delivery
• Local Government Areas - Government
• Natural Boundaries - NRE
• Electrol Boundaries - Voting
• etc....

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Focus

• Impossible to solve all of the incompatible
  boundary problems at once
• Collector District and Postcode Boundaries
• Cross analysis between these two boundaries
  restricted due to incompatible boundary
  units..for example

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East Gippsland
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Health Example

• Analysis of health related data is restricted by
  incompatible boundary units.
• Health system collects data on postcode
• Demographics are based on the ABS collector
  district

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North West Melbourne Health Division
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Possible Solutions

• Aggregation from point data to new boundaries
• Data Interpolation
• ?Reorganisation of Boundaries

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Interpolation Process

• Data Interpolation
• Formula
• Vt ? Us(ast/?ast)
• Errors

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Interpolation Errors
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Reorganisation Process

• Concept
• Knowledge of the properties and relationships
  associated with each set of spatial Units

Formalisation
Prototype
Implementation
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Concept Continued
Postcode Defined by Australia Post Facilitate
Mail Delivery Defined along major roads Thematic
Maps display and Analysis
Collection District Defined by ABS Facilitate
Demographic Data Collection 200 households or
area that 1 collector can cover in a 10 day
period Thematic Maps display and Analysis
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HSR Requirements (Adrijana Car)

• Hierarchical structure and a method to transform
  the non hierarchical structure to the equivalent
  hierarchical one
• A set of rules on how to reason on the
  hierarchical structure

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Issues to be considered

• Common link between the organisations and the
  function they provide
• Modifiable Area Unit Problem (MAUP)
• Scale (level of aggregation)
• Zoning (boundary position)

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Cont

• Barriers
• Large scale Berlin Wall
• Small scale Lakes, Highways
• Well defined on the ground
• Roads
• Land Parcels
• Education of Industry - Benefits of a uniform
  system
• Difference between Rural and Urban regions

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Conclusion

• GIS is a key spatial analysis tool currently
  restricted by incompatible boundary units
• The proposed solution to this problem is an
  hierarchically based integrated network of
  boundaries.

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Exam Questions

• Discuss the possibilities and issues of applying
  Spatial Hierarchy Reasoning to spatial boundaries
• List and describe three different approaches to
  solve the problem of data exchange amongst
  non-coterminous boundaries