1. Introduction

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Lecture 17 GIS Analytical Functionality (I)
Topics (Coverage So Far)
1. Introduction 1.1 Spatial Queries 1.2
Classification of GIS Analytical Functionality
Readings on the topics
Chapter 14 in Longley et al. (2005) pp.
315-322 Chapter 7 in Aronoff (1993) pp. 189-197
Other readings
Chapter 5 in Bonham-Carter (1994) pp.
134-137 Chapter 7 in Burrough and McDonnell
(1998)pp.163-164)
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Outlines
1. Introduction 1.1 Spatial Queries
1.1.1 What is a spatial query?
Questions addressing the spatial distributions of
geographic features and of the
interactions among these features.
Must involve spatial location(s) of geographic
features 1.1.2 Types of Spatial Queries
1.1.2.1 Location (what is at?)
Find out what exists at a particular location
Examples What is the real
estate value at that location?
What is the customer support around that shopping
center? What is the annual yield
of the farm across the river?
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1.1.2 Types of Spatial Queries
(Continued) 1.1.2.2 Condition (Where is
?) Find out the locations where
certain conditions are satisfied
Examples Find the Crane
habitats in Missouri Find the
potential sites for a new landfill in Dane County
Show the
households with more than 3 children in Chicago
1.1.2.3 Trends (What has changed since
?) Find out the differences in an
area over time Examples
Has the voting behaviour changed in Los Angles
since 1990? Has the custom
support for West Town Mall changed since 2000?
Has the
severity of soil erosion decreased since the
implementation of the
conservation practice?
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1.1.2 Types of Spatial Queries
(Continued) 1.1.2.4 Patterns
(relationships) (What relationships exist?)
Determine if a spatial phenomenon is
related to the existence or removal
of another spatial phenomenon (entities)
Examples Whether cancer is a
major cause of death among residents near a
nuclear power plant?
Whether the emigration of deer is related to
the diminishing of a
particular grass?
Is improper manure application the major
cause of stream pollution? 1.1.2.5
Modelling (What if ?) Determine what
would happens if the status of a spatial
entity changes Examples
What would happen to the traffic
conditions if a new road is built?
What would happen to the sediment yield if a
particular landuse is changed?
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1.2 Classification of GIS Analytical Functions
1.2.1 Based on what it can do (1)
Measurements (2) Connectivity
(3) Interpolation (4) Terrain Analysis
(5) Statistical Analysis (6)
Spatial Overlay 1.2.2 Based on the number of
layers involved (a) On single layer
(b) On two layers (c) On three or
more layers
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Questions
1. What kind of questions can GIS answer? 2.
What is a spatial query? Why is GIS particularly
suited to address spatial queries? 3. What are
the different types of spatial queries? Give an
example for each of them.