Two researcher interfaces

1
GIS
Ilya Zaslavsky and other members of DICE
2
Outline

• Whats a GIS
• Applications, ArcView demo
• Myths
• Some interesting problems
• GIS on the Web, and XML

3
Simple Definition

• GIS Maps in Computers

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Smart Maps
Site Number Bacteria 104
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What Is GIS - a Brief Introduction
a system of hardware, software, data, people,
organizations and institutional arrangements for
collecting, storing, analyzing, and disseminating
information about areas of the earth (Dueker and
Kjerne, 1989)

• Different mapping systems
• Electronic atlases
• Thematic mapping systems
• Street-based mapping systems
• GIS all these things much more
• analysis, import/export, combination of different
  data, dynamic map update, etc

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How GIS Works

• Link map features to tables of attributes
• Access the attributes for any map feature
• Locate any feature from its attributes
• Manage sets of features attributes as themes or
  objects

• Integrate sources
• - Primary sources
• - Secondary sources

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Integrate Sources
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Geographic Database
Framework Data
Thematic Data
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Exploring Relationships

• Based on geographic location and proximity, GIS
  makes connections between activities
• Looking at data geographically can often suggest
  new insights, explanations
• These connections are often unrecognized
  without GIS, but can be vital to understanding
  and managing activities and resources
• E.g., we can link pollution sources with disease
  patterns

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Combining data sets
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Pollution Sources
Leukemia Cases
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Information about where allows us to combine
heterogeneous data sets
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Space as an indexing system
Rivers


Settlements



Admin. Units
Reference Grid
Latitude
Longitude
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Projections

• Example The Mercator projection has straight
  meridians parallels that intersect at right
  angles, as opposed to the Robinson projection.
• Mercator preserves area only at the equator and
  at two standard parallels equidistant from the
  equator.
• The Mercator projection is often used for marine
  navigation as all straight lines on the map are
  lines of constant azimuth.
• Any one projection cannot simultaneously preserve
  all these qualities of the world shape, area,
  direction, and distance.

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This is what happens when projections mix!

• Notice the boundary lines do not line up
• Points that are placed on the wrong projection
  will be misaligned as well

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What does it mean doing GIS?

• Using the tools of GIS to solve a problem
• Helping to build the tools
• Adding to existing geographic information
  technologies
• Helping to invent or develop new ones
• Studying the theory and concepts that lie behind
  GIS and the other geographic information
  technologies
• Studying the societal context of geographic
  information
• The legal context
• Issues of privacy, confidentiality
• Economics of geographic information

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GIS in Higher Education

• ESRI list of GIS programs
• http//gis.esri.com/university/onlinedb.cfm
• GIS Programs in Higher Education
• http//www.directionsmag.com/education/
• Geography departments worldwide
• http//geowww.uibk.ac.at/geolinks/
• Directory of graduate schools, GIS programs
• http//www.gradschools.com/listings/menus/geoinfos
  ys_menu.html

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GIS Curriculum - 1

• UCSB (http//www.geog.ucsb.edu/programs/ugrad_cour
  ses.htm )
• Geog 12 - Maps and Charts, 4.0, Clarke
• Geog 13 - Introduction to Computing in Geography,
  2.0, Staff
• Geog 115A - Geographic Photo Interpretation, (T),
  4.0, Estes
• Geog 115AL - Laboratory in Geographic Photo
  Interpretation, (T), 1.0, Estes
• Geog 115B - Geographic Remote Sensing Techniques,
  (T), 4.0, Mertes
• Geog 115BL - Lab in Geographic Remote Sensing
  Techniques, (T), 1.0, Mertes
• Geog 115C - Intermediate Geographic Remote
  Sensing Techniques, (T), 4.0, Mertes
• Geog 115CL - Laboratory in Intermediate
  Geographic Remote Sensing Techniques, (T), 1.0,
  Mertes
• Geog 118 - Production Cartography, (T), 4.0,
  Clarke
• Geog 128 - Analytical and Computer Cartography,
  (T), 4.0, Staff
• Geog 136 - Remote Sensing of the Oceans, (GT,
  UT), 4.0, Washburn
• Geog 138 - Remote Sensing of the Atmosphere An
  Introduction, (T), 4.0, Gautier
• Geog 151 - Computational Methods for Watershed
  Analysis, (T), 5.0, Mertes
• Geog 172 - Introduction to Geographical Data
  Analysis, (T), 3.0, Montello
• Geog 172L - Laboratory in Introductory
  Geographical Data Analysis, (T), 2.0, Montello
• Geog 176A - Introduction to Geographic
  Information Systems, (T), 4.0, Goodchild, Clarke
• Geog 176B - Technical Issues in Geographic
  Information Systems, (T), 4.0, Goodchild, Clarke
• Geog. 176BL - Lab in Geographic Information
  Systems I, (T), 1.0, Goodchild, Clarke

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GIS Curriculum - 2

• SDSU http//typhoon.sdsu.edu/
• GEOG 380 Map Investigation
• GEOG 381 Map and Graphic Methods
• GEOG 385 Spatial Data Analysis
• GEOG 484 Geographic Information Systems
• GEOG 488 Remote Sensing of Environment
• GEOG 581 Cartographic Design
• GEOG 582 Automated Cartography
• GEOG 584 Geographic Information System
  Applications II
• GEOG 585 Quantitative Methods in Geographic
  Research
• GEOG 588 Intermediate Remote Sensing of
  Environment
• GEOG 682 Advanced Automated Cartography
• GEOG 683 Advanced Geographic Information Systems
• GEOG 685 Advanced Quantitative Methods in
  Geography
• GEOG 688 Advanced Remote Sensing
• GEOG 780 Seminar in Techniques of Spatial
  Analysis

• University of Washington
• 258 Maps and GIS
• 360 Principles of Cartography
• 458 Map Sources and Errors
• 460 Geographical Information System Analysis
• 461 Urban Geographic Information Systems
• 463 Geographic Information Systems Workshop
• 465 Analytic Cartography

• Western Michigan University
• 375 Intro to GIS
• 582 Remote Sensing of the Environment
• 566 Field Geography
• 567 Computerized Geodata Handling and Mapping
• 569 Geographic Information System

The NCGIA Core Curriculum in GIScience
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Applications
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Redistricting
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Disaster recovery
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Floodplain mapping
500 year flood
100 year flood
Hurricane Floyd
Flooding in Greenville
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Regulation implementation enforcement
100 year flood
Hurricane Floyd
Hog lagoons in and out of the floodplain
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Watershed planning
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Zoning
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Smart growth
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Police and fire deployment
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Residential development
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Economic development
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Fund allocation
Prime Farmland in Johnston County
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Intelligent demographics
32
Citizen access to public data
Preserved Lands in North Carolina
33
Myths
34
Some Myths About GIS

• GIS provides an objective approach to
  information
• Data may be different methods may be different
• Similar GIS for the same area will lead to
  similar conclusions and policy recommendations
• Attitudes may be different
• Digital geographic data are accurate
• Well and there are so many ways to measure data
  quality
• Better information will make better decisions
• Another top 5 and another and another . 6
  myths!
• Technical issues are fundamental in GIS

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Summary of annual hazardous waste crossing the
U.S./Mexico border during 1995-1997 (tons/yr)
HAZTRAKS (EPA) Border Maquilas (INE) Transport from U.S. Industries to Mexico (INE)
1995 8,510 33,187
1996 6,983 72,113 230,417
1997 11,057 76,808 284,921
EPAEnvironmental Protection Agency
INEInstituto Nacional de Ecología About 2 of
the hazardous wastes generated in the border
states

• procedural differences in accounting
• incomplete coverage
• regional differences
• differences between industries

Source Robert G. Varady, Robert G. Arnold, Dean
E. Carter, Roberto Guzmán, Carlos Peña, William
A. Suk, 2000 Hazardous Waste and the
U.S.-Mexico Border Region
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Some Interesting ProblemsSemanticTechnicalStati
stical
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sometimes, the distinction between discrete and
continuous is not very clear
GIS representation
reality
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Objects versus Fields

• Object viewempty space littered with objects
  (points, lines or areas)
• Field viewvalue is defined for every location

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Objects
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Fields
Raster grid
Regular point grid
Irregular points
Contour lines
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AUTOCORRELATION Land Use Maps Example

• Categorical maps inherently autocorrelated
• Degree of autocorrelation depends on resolution

In vector database

• if areas of polygons Area Lim(NS), where
  N - number of cells, S - size of a cell, S
  --gt0 autocorrelation extremely
  positive
• if counts of polygons no adjacent polygons
  with the same value
  autocorrelation extremely negative

43
MAUP - Modifiable Areal Unit Problem

• Group of problems
• Scale (The larger the unit of aggregation, the
  larger, on average, is the correlation between
  two variables)
• Aggregation (Taylor and Johnston (1979) in The
  geography of elections obtained a 0.44
  correlation between rural non-farm voting for
  Nixon in 1960 using Census nine-region division
  and a -0.22 correlation using the four-region
  division)
• Openshaw, Taylor 1979 A million or so
  correlation coefficients three experiments with
  the modifiable areal unit problem
• How to solve MAUP (Openshaw, 1983)
• ...it is not likely that solution exists that
  would allow the use of traditional techniques
• ...the simplest is to pretend that it doesn't
  exist
• ...the most convenient solution - to accept that
  zoning systems are independent of the phenomena
  they are used to report

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GIS on the Web
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Opportunity in Web-based Mapping

• Disaster relief and Emergency management
• Global and national geospatial information
  infrastructures
• Digital Earth, NSDI, GSDI
• Crime management
• Environmental Monitoring
• Many others...

World Wide Web
Clients
Internet
Servers
Email
FTP
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Web Mapping Defined
Web servers and map viewer clients interact to -

• Discover, access and retrieve views from
  multiple servers

• Display multiple layers of geographic data
  within a single web application

• Query and update

• Provide interface for visualization, Decision
  Support, etc.

• Support geocoded raster, vector, matrix, and
  other data

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Mapping on the Web Today
How can I combine data from each of these sources
to answer my question?
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Web Mapping TodayCharacteristics

• Specialized applications that meet specific needs
• Relatively easy to use
• Limited ability to integrate information from
  other sources

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Web Mapping Technology Initiative - Method --New
Way of Doing Business

• Bring together web mapping technology developers
  and users from around the world
• Develop multi-use (civil, business, military,
  etc) open technology interfaces
• Rapidly document open interface specifications
• End result are Standards-based commercial
  off-the-shelf (SCOTS) products.

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The Three Architecture Cases
The Graphic Element Case
The Data Case
The Picture Case
(source OpenGIS document 99-077)
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Architectures for Different Applications

• Each map request sends new geometry
• Examples find by address or another attribute
  routing, single-attribute maps, weather maps,
  etc.
• In general situations when geometry is defined
  by attribute (categorical coverages, for example)
• Geometry remains relatively constant
• Examples atlases, statistical maps for
  collection zones (states, counties, census
  tracts)
• In general situations with many attributes for
  limited number of geometries
• For the latter case makes sense to cache and
  re-use coordinate information on the client side
  as much as possible. For each application, there
  is some right mix of the two approaches.

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XML the emerging Web data interchange standard

• XML eXtensible Markup Language
• Supports semi-structured data provides for
  semantic tagging, separation of content from
  presentation
• W3C recommendation, 1998
• XML for 2D vector rendering
• 1st generation VML, PGML
• 2nd generation SVG (W3C Candidate
  Recommendation)
• XML for expressing geographic coordinates
• GML (Geographic ML), etc need to be rendered in
  VML, SVG or similar for vector display

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GIS XML 1st experiment (the data)
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GIS XML 1st experiment (XML wrapping)
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GML

• GML XML specification to encode geo. info.
• For both Data Storage Data Transport
• Initial release deals with OGC Simple Features
• vector geodata e.g. digital map info (streets,
  population, land use zones, property lines,
  watersheds, etc.)
• 3 profiles from lite to RDF, but likely to
  change with XML schemas
• GML is not concerned with the visualization of
  geographic features (drawing of maps)

Graphic format
Direct rendering
Direct routing w.o. viz.
Numerical model
GML in XML
Transformation into a vector graphics rendering
format

• SVG
• VML
• VRML

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From Geography Markup to Rendering
lt?xml version"1.0" encoding"iso-8859-1"?gt ltrsgt lt
rgtltnamegtHorton Plazalt/namegtltURLgtlt/URLgtltlabelposgt41
.46,77.51lt/labelposgtltcgt5076,1540 4986,1540
4895,1539 4803,1539 4715,1539 4622,1539 4534,1538
4534,1641 4534,1745 4534,1856 4622,1856 4711,1856
4800,1856 4893,1855 4984,1855 5075,1854 5075,1749
5076,1646 lt/cgtlt/rgt ltrgtltnamegtGaslamplt/namegtltURLgtlt/U
RLgtltlabelposgt44.60,83.00lt/labelposgtltcgt5162,1013
5084,1057 5083,1116 5081,1222 5079,1326 5079,1433
5076,1540 5076,1646 5075,1749 5075,1854 5167,1854
5257,1855 5257,1750 5259,1647 5260,1541 5262,1434
5262,1328 5263,1222 5263,1013 lt/cgtlt/rgt . . .
XML encoding of geographic features (such as GML)
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Applications XML-based mediation for spatial
data sources
Native XML/VML repository
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Some examples

• MCSP

• Vietnam War

• Witchcraft project

• Michigan Atlas

• LTER

• Amer Transportation Survey

• Quality of Life in San Diego maps

• Rat Brain Atlas (the SMaRT tool)