Principles of GIS - Capita

Principles of GIS
CE/ENVE 424/524
GIS
Traditional definition is that GIS is a set of computer tools for accessing,
processing, visualizing, analyzing, interpreting, and presenting spatial data.
‘GIS’ is Geographical Information System AND
Geographical Information Science
GISystems: Emphasis on technology and tools
GIScience: Fundamental issues raised by the use of GIS, such as
Spatial analysis
Map projections
Accuracy
Scientific visualization
Implementation and application of GIS covers a wide spectrum:
Simple maps
Overlaying multiple map “layers”
Conducting proximity or cluster analysis based on distance
Comparing data sets (simple spatial statistics)
Complex statistical analysis

Views to a GIS
Map view:
Focus on cartographic (mapping) aspects of GIS
Thematic GIS layers
Input map => Output map
Database view:
Focus on database management system
Simple queries to retrieve and overlay data
Spatial analysis view:
Focuses on analysis and modelling
Views GIS more as information science
Organizational view:
Focuses on decision support systems
An approach to managing an organization’s data,
information, and knowledge
GIS as Toolbox
GIS is "a powerful set of tools for collecting, storing, retrieving at will,
transforming and displaying spatial data from the real world for a
particular set of purposes"
(Burrough and McDonnell, 1998)
GIS are "automated systems for the capture, storage, retrieval,
analysis, and display of spatial data" (Clarke, 1995)
GIS is “an information technology which stores, analyses, and displays
both spatial and non-spatial data” (Parker 1988)

GIS as Database
GIS is “a database system in which most of the data are spatially
indexed, and upon which a set of procedures operated in order to
answer queries about spatial entities in the database” (Smith et al.,
1987)
"A geographic information system is a special case of information
systems where the database consists of observations on spatially
distributed features, activities or events, which are definable in
space as points, lines, or areas. A geographic information system
manipulates data about these points, lines, and areas to retrieve
data for ad hoc queries and analyses" (Dueker, 1979)
GIS as Spatial Analysis
"An information system that is designed to work with data referenced
by spatial or geographic coordinates. In other words, a GIS is both a
database system with specific capabilities for spatially-referenced
data, as well as a set of operations for working with the data" (Star
and Estes, 1990)
“The true potential value of Geographical Information Systems lies in
their ability to analyze spatial data using the techniques of spatial
analysis" (Goodchild, 1988)
"GIS technology integrates common database operations such as query
and statistical analysis with the unique visualization and geographic
analysis benefits offered by maps. These abilities distinguish GIS from
other information systems and make it valuable to a wide range of
public and private enterprises for explaining events, predicting
outcomes, and planning strategies." (ESRI 1997)

GIS as Organization
“ a decision support system involving the integration of spatially
referenced data in a problem-solving environment” (Cowen, 1988)
“ an institutional entity, reflecting an organizational structure that
integrates technology with a database, expertise and continuing
financial support over time” (Carter, 1989)
“organized activity by which people measure and represent
geographic phenomena, and then transform these
representations into other forms while interacting with social
structures.” (Chrisman, 1999)
GIS as Science
GI Science addresses "the generic issues that surround the use of GIS
technology, impede its successful implementation, or emerge from
an understanding of its potential capabilities." (Goodchild, 1992)
It makes “more sense for the research community to decode the GIS
acronym in this way, focusing on the generic issues of spatial
data, rather than on the limited solutions offered by today's
geographic information system products. “ (Goodchild, 1995)

A Brief History of GIS
• GIS is relatively young but mapping and spatial analysis preceded it
by hundreds of years
• Manual map overlay as a method was first described
comprehensively in a 1950 textbook
• Mathematics for spatial analysis were developed in the 1930s and
1940s
• GIS evolution parallels that of general information technology
A Brief History of GIS – 1960s
• The 1960s saw the advent of geographic data and mapping software
• First GIS was the Canada Geographic Information System developed
for land resource measuring and inventory analysis
• The Harvard Laboratory for Computer Graphics and Spatial Analysis
established
• Aeronautical Charting and Information Center in St. Louis
• US Defense Mapping Agency in St. Louis (now NIMA – National
Imagery and Mapping Agency)

A Brief History of GIS – 1970s
• Gridded data analysis programs
• Rudimentary graphics
• ESRI (Environmental Science and Research
Institute) established
• Intergraph
• Increased use by government agencies
• Satellite imagery (Landsat)
• Dual Independent Map Encoding (DIME) for census areas
• GIS Functions for points and polygons
A Brief History of GIS – 1980s
• ESRI ArcInfo
• Global Positioning System (GPS)
• GIS Journals and Conferences
• MapInfo
• TIGER (Topographically Integrated Geographic
Encoding and Referencing) Census project
• Academic GIS courses
• Widespread acceptance
• Increased availability of satellite imagery

A Brief History of GIS – 1990s
• Migration to PC
Open GIS Consortium
National Spatial Data Infrastructure (NSDI)
Web GIS
Integration of geospatial data
GIS Day
A Brief History of GIS – 2000s
• WebGIS
• Wireless (PDAs, cell phones)
• Embedded Sensor Networks
• Distributed Databases
• GIServices

• Organized collection of
– Hardware
– Software
People
– Network
– Data
– People
– Management
Components of GIS
“GIS should be viewed as a process rather than as merely
software or hardware.” (Malczewski, 1999)
SAPs
Network
Hardware
GIS Software Architecture
User Interface
Tools
Data Management
Data
Software
Viewers, Controls
Data
Management
Display, Analysis, Manipulation
Data Access, Conversion

GIS Software Classification
Number of
Users
Internet
Viewer
Component
Hand-held
Desktop
Professional
Functionality
GIS Software Packages
Cost
Autodesk ESRI Intergraph MapInfo GE Network
Solutions
Viewer AutoCAD
LT
ArcReader GeoMedia Viewer ProViewer Custom
Desktop World ArcView GeoMedia MapInfo
Spatial
Professional Intelligence
Profess- AutoCAD / ArcEditor GeoMedia Pro MapInfo
Smallworld GIS
ional Map ArcInfo
Professional
Hand-held OnSite ArcPad IntelliWhere MapXtend Scout
Database
Server
Design
Server
Component In several
products
ArcSDE Uses Oracle
Spatial
Map
Objects
Internet MapGuide ArcIMS GeoMedia Web
Map, GeoMedia
Web Enterprise
CAD AutoCAD
Map
In several
products
SpatialWare Part of
Smallworld GIS
Part of GeoMedia MapX, MapJ Part of
Smallworld GIS
In several
products
MapXtreme,
MapXSite
In several
products
Smallworld
Internet Application
Server
Part of
Smallworld GIS

GIS Market
Revenues for 2001 - $1.1 Billion (14.3% growth over previous year)
Market Share (2002)
ESRI - 35%
Intergraph - 13%
GE Network Solutions - 7%
Autodesk - 7%
Leica - 6%
Mapinfo - 6%
IBM - 5%
SICAD - 5%
Logica - 3%
Other - 14%
Largest market for GIS Software: Utilities industry (21%), followed by state and local
governments
Total GIS Front-End Business tops $7.7 Billion
GIS-Related Services Reach $5.4 Billion
GIS Drives $799 Million in Hardware Sales
Others:
Idrisi
GRASS
ArcGIS System Architecture

ArcMap
ArcGIS Main Components
ArcCatalog
ArcToolbox
ArcMap
Central ArcGIS application
Handles map-based tasks

ArcCatalog
Organizes and manages GIS data
ArcCatalog

ArcToolbox
GIS Data Formats
Contains the tools for
geoprocessing

Working in ArcGIS
ArcGIS Extensions
Special functionality can be added to ArcGIS through
extensions. We will be have access to the following
extensions:
•Spatial Analyst
•Geostatistical Analyst
•3D Analyst

Spatial Analyst
Geostatistical Analyst
Raster and Vector
Analysis
Advanced spatial
analysis

3D Analyst