Geographic Information Systems
SGO 1910, 4930
November 8, 2005
Announcements


eSeminar in GIS: Putting the e into GI Science
(Mark Birkin, Leeds). Thursday, November 17,
room 3514 Georg Sverdups Hus.
Norsk ESRI brukerkonferanse 2006
Den 17. norske ESRI brukerkonferansen går av
stabelen 1. -3. februar 2006. Konferansen byr på
en rekke foredrag, tekniske minikurs,
bransjeseminar og sosiale aktiviteter. Vi ser frem
til spennende dager sammen med deg! Påmelding
og mer informasjon kommer senere.
Announcements
Extended access to GIS lab during Nov.Dec?
 GIS Internships: Any interest?

Oslo Project Groups
1.
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4.
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6.
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11.
12.
13.
Marita Sanni, Kristin I. Dankel, Solveig Melå + Svein Johan Hansen?
Åslaug Enger Olsen, Maria Lyngstad, Guro Bakke Håndlykken og Jorunn Randby
(4)
Nina Ambro Knutsen, Ellen Winje og Leif Ingholm, Gjermund Steinskog (4)
Birte Mobraaten, Hans Petter Wiken, Silje Hernes and Bente Lise Stubberud (4)
Daniel Molin, Ida Sjølander, Anne-Lise Folland and Nicolai Steineger (4)
Hæge Skjæveland, Marie Aaberge, Cecilie Hirsch, Kaja Korsnes Kristensen (4)
Urs Dippon, Steven huiching Yip, Harald Kvifte & Eirik Waag (4)
Marthe Stiansen, Marielle Stigum, Tomas Nesset, Andreas Skjetne (4)
Andreas Dyken, Håkon Grevbo, Terje-Andre Gudmundsen, Øystein Kristiansen (4)
Andreas Wilhelm Westgaard, Grete Simensen og Ingvild Jøranli, Solveig Lyby (4)
Linda Markham, Marte Hunsdal Knutsen, Anette Nesvold, Berit Indset (4)
Magnus Campbell, Johannes Devik Brekke, Espen Fait, Mathias Ødegård (4)
Julie Aaraas, Tonje Einarsen, Anne Marie Skancke, Bård Bergland (4)
Making Maps With GIS
Introduction
Output is the pinnacle of GIS projects
 Two main types of output

– Maps
– Visualizations (see chapter 13)

Maps are good at summarizing and
communicating
What is a map?

“A graphic depiction of all or part of a
geographic realm in which the real-world
features have been replaced by symbols in
their correct spatial location at a reduced
scale.”
power line
Map function in GIS
Storage
 Temporary communication
 Intermediate check of data
 Final report

GIS Processing Transformations
Characteristics of Map

Two main types
– Topographic
– Thematic

Some map problems
– Can miscommunicate
– Each map is just one of all possible maps
– Complex maps can be difficult to understand
Topographic Map
Thematic Map
Map Types
Point data
 Line data
 Area data
 Volume data
 Time data

Choosing a Map Type
Cartographers have designed hundreds of
map types: methods of cartographic
representation.
 Not all GISs allow all types.
 Most have a set of basic types
 Depends heavily on the dimension of the
data to be shown in the map figure.

Choosing the Wrong Type
Fairly common GIS error.
 Due to lack of knowledge about
cartographic options.
 Can still have perfect symbolization.
 Possibility of misinformation
 Definite reduction in communication
effectiveness.

Choropleth
Class Schemes
Choosing Types





Check the data
– Continuous
– Discrete
– Accuracy & Precision
– Reliability
Dimension (Point, Line, Area, Volume)
Scale of Measurement (Nominal, ordinal, etc.)
GIS capability
Is there a need to supplement GIS software? (e.g. with a
drawing package)
Maps and Cartography
Map – ‘digital or analog output from a GIS
showing information using well established
cartographic conventions’
 Cartography is the art, science and
techniques of making maps

The Need for Design
To appear professional and avoid errors,
GIS maps should reflect cartographic
knowledge about map design.
 A map has a visual grammar or structure
that must be understood and used if the best
map design is desired.
 Cartographic conventions should be
followed (e.g. forests should be green).

Map Design
Good map design requires that map
elements be placed in a balanced
arrangement within the neat line.
 A GIS map is designed in a process called
the design loop.

To be effective, a map must be
correctly designed and
constructed.
The Parts of a Map: Map Elements
Border
Neat line
Title
The United States of America
Figure
Legend
Ground
Alaska
0 1 2 3 4
Hawaii
0 4
Inset
Scale
Washington,D.C.
National Capital
hundreds of
kilometers
04
Place name
Lambert Conformal Conic Projection
Source: U.S. Dept. of State
North Arrow
Credits
Inset map
Scale
Author
North Arrow
Data Source
Map Body
Projection
Title
Grid
Legend
Bertin's Graphic
Primitives
Visual balance is key!
Visual balance is affected by:
 the "weight" of the symbols
 the visual hierarchy of the symbols and
elements
 the location of the elements with respect to
each other and the visual center of the map.

Visual center
5% of height
5% of height
Landscape
Portrait
Visual Layout
Title Here
Title Here
Eye expects (1) balance and (2) alignment
Text: Selection and Placement
BM 232
POINT
LINE
Oslo
Bærum
Kristiansand
AREA
Some cartographic label placement conventions. Points: right and above preferred with no overlap.
Lines: Following the direction of the line, curved if a river.
Areas: On a gently curved line following the shape of the figure and upright.
Text placement
Trondheim
Trondheim
Path right
Trondheim
Trondheim
Bogstadvann
P
a
t
h
D
o
w
n
Symbol “weight”
Line weight
Pattern
Shading
Hue
Map Design and GIS
When a GIS map is the result of a complex
analytical or modeling process, good design
is essential for understanding.
 The map is what distinguishes GIS as a
different approach to the management of
information, so extra care should be taken
to improve the final maps that a GIS
generates in a GIS task.

Limitations of Paper Maps
Fixed scale
 Fixed extent
 Static view
 Flat and hence limited for 3D visualization
 Only presents ‘complete’ world view
 Map producer-centric

Conclusions
Cartography is both an art and a science
 Maps are fundamental to GIS projects
 Modern advances in cartography make it
easy to produce good and bad maps
 New technology and especially the Internet
has change the content and techniques of
GIS-based cartography

Multivariate Mapping