Geographical Information System (GIS) to Knowledge

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Geographical Information System (GIS) to Knowledge
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Outline

• Problem Statement
• Top Level Overview
• Input Information Extraction and Representation
• Georeferencing and Raster Information Extraction
• Feature Driven Boundary Aggregation and
  Evaluation
• Error Evaluation of New Boundary Aggregations and
  Decision Making
• Summary

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Acknowledgement

• Project Team Members Peter Bajcsy, Peter Groves,
  Sunayana Saha, Tyler Alumbaugh
• Support Michael Welge, Loretta Auvil, Dora Cai,
  Tom Redman, David Clutter, Duane Searsmith, Lisa
  Gatzke, Andrew Shirk, Ruth Aydt, Greg Pape, David
  Tcheng, Chris Navaro, Marquita Miller.

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Problem Statement

• Problem Statement search for the best partition
  of any geographical area that is
• (a) based on raster or point information,
• (b) formed by aggregations of known boundaries,
• (c) constrained or unconstrained by spatial
  locations of know boundaries and
• (d) minimizing an error metric.
• Raster or Point Information
• Grid-based information, e.g., from satellite or
  air-borne sensors
• Geographical point information, e.g., from GPS or
  address data base
• Boundaries (Vector Data)
• Man-made, e.g., Counties, US Census Bureau
  Territories
• Defined by environmental characteristics, e.g.,
  Eco-regions, Historical iso-contours
• Spatial Constraints and Error Metric
• Defined by applications

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Top Level Overview

• References
• ALG Technical Reports TR-20030226-1.doc,
  TR-20030211-1.doc, TR-20021011-1.doc
• Conferences Peter Bajcsy and Tyler Jeffrey
  Alumbaugh, Georeferencing Maps With Contours,
  Proceedings of the 7th World Multiconference on
  Systemics, Cybernetics and Informatics (SCI
  2003), Orlando, Florida, July 27-30, 2003.
• Peter Bajcsy, Automatic Extraction Of
  Isocontours From Historical Maps, Proceedings of
  the 7th World Multiconference on Systemics,
  Cybernetics and Informatics (SCI 2003), Orlando,
  Florida, July 27-30, 2003.

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Input Information Extraction and Representation
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Input Information Extraction and Representation
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Data Types and Representation Examples

• Raster Information GeoImage Object
• Boundary Information Shape Object
• Tabular Information Table Object
• Neighborhood Information NBH Object

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Raster Data File Formats

• USGS Digital Elevation Data (DEM) Files
• Header file with georeferencing information
• Floating point values, 30 m spatial resolution,
  IL coverage, published in 2002
• TIFF Files
• Georeferencing information from
• One or more standardized files are distributed
  along with TIFF image data as .tfw and/or .txt
  files.
• The metadata is encoded in the image file using
  private TIFF tags.
• An extension of the TIFF format called GeoTIFF is
  used.
• Forest labels, 1km spatial resolution,
• Forest Cover Types 29 labels, USA coverage,
  published in 2000
• Forest Fragmentation Index Map of North America,
  8 labels, USA coverage, published in 1993
• Land use labels, 1km spatial resolution, world
  wide coverage, published in 2001

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Vector Data File Formats

• Computational Tradeoffs Between Vector
  Information Retrieval and Data Storage
• US Census Bureau TIGER Files
• Elaboration of the chain file structure (CFS)
• Used record files 1, 2, I, S, P
• Environmental Systems Research Institute (ESRI)
  Shapefiles
• Location list data structure (LLS)
• shp, shx, dbf files
• TIGER to ESRI Shapefiles

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Point Data File Formats

• FBI Crime Reports
• United States Crimes Database, years 94-98, USA
  states, reports per county, published in 2001
• United States Crimes Database, years 98-00, IL
  state, reports per county, published in 2002
• Entries
• Theme_Keyword crime, arrests, murder, forcible
  rape, rape, robbery, aggravated assault, assault,
  burglary, larceny, motor vehicle theft, theft,
  arson
• Challenges
• Multiple Files
• Varying notation
• Association with geographical boundary
  information

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Data Size

• Data size driven operations
• Sub-setting
• Sub-sampling
• Cropping
• Zooming

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Formation of Vector Data

• Iso-contour extraction from historical maps
• Segmentation and clustering of raster data into
  homogeneous regions

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Georeferencing Data Sets and Raster Information
Extraction
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Georeferencing Data Sets and Raster Information
Extraction
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Georeferencing Based on Data Types

• Raster and Raster
• Vector and Vector
• Raster and Vector

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Georeferencing Based on Coordinate Systems
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Raster Information Extraction Categorical
Variable
Frequency of Occurrence
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Raster Information Extraction Continuous Variable





Elevation Statistics Per County
Standard Deviation
Sample Mean
Skew
Kurtosis
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Feature Driven Boundary Aggregation and Evaluation
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Feature Driven Boundary Aggregation and Evaluation
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Spatially Unconstrained Boundary Aggregation

• Hierarchical clustering of crime data with the
  exit criterion being the number of clusters and
  the clustered feature being auto theft in 2000
  leads to six aggregations.

Tabular Display
Geographical Display
Boundaries
Boundary Aggregations
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Spatially Constrained Boundary Aggregation

• Hierarchical segmentation and hierarchical
  clustering of oak hickory feature with the exit
  criterion of 18 numbers of county aggregations

With Spatial Constraint
Without Spatial Constraint
Boundaries
Boundary Aggregations
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Boundary Aggregation With Hierarchical Output

• Hierarchical segmentation of extracted forest
  statistics (oak hickory occurrence) with two
  output partitions.

43 aggregations
21 aggregations
Boundaries
Boundary Aggregations
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Error Evaluations of New Territorial Partitions

• Error evaluation of partitions obtained by
  clustering and segmentation of mean elevation
  feature per Illinois county with Variance error
  metric

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Geographical Error Evaluations and Decision Making

• Geographical error evaluation of partitions
  obtained by clustering and segmentation of mean
  elevation feature per Illinois county with
  Variance error metric

Partition Index
Eval0
Eval1
Eval2
Eval3
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Decision Making

• Which global partition minimizes a chosen error
  metric?
• Which partition minimizes a chosen error metric
  at a selected fundamental area definition?
• What is the geographical error distribution given
  a territorial partition?

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Documentation
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Summary

• Applications of GIS tools
• Remote Sensing
• Agriculture
• Hydrology
• Water Quality Survey
• Atmospheric Science
• Military
• Socio-Economics
• Interested ? Useful ? Let us know.