Maps: Two-dimensional, scaled representations of
Earth surface - show spatial data (data with
locational component)
Cartography (map-making) involves 5 design
decisions – based on purpose of map





Projection
Simplification
Scale
Aggregation
Type of Map (thematic* or reference)
THEMATIC MAPS – depict characteristics of places
Categorical type
- Depict areas that are different in kind
- Use several distinct colors to show different categories
desert
forest
tundra
Examples: climates, religions
Choropleth type
- Depict areas that are different in amount
- Use shades of similar colors to show different values
high value
medium
Examples: population density, literacy rates
low value
Example of “categorical map”
Example of “choropleth map”
Human Development Index (HDI) Rankings
Includes GNI/PPP, Literacy, and Life Expectancy
Which regions have high HDI?
Which regions have low HDI?
Which places are exceptions?
Isoline type
(Average Daily Solar Radiation)
Lines connect points of
equal value
Dot Density type
(Wisconsin Acreage in Potatoes)
Each dot represents a
frequency of mapped variable
Proportional Symbol Map
(Graduated Circle type)
Size of symbol varies in relation to
frequency or intensity of the
mapped variable
Proportional Symbol Map
(Flow Vector type)
Sample Map Projections
Mercator
Robinson
Systematic methods of
transferring a spherical
surface to a flat map
Distortion must occur in
either size, shape,
distance, or direction – all
projections are
compromises
Polar
Equal-Area projections best where purpose is to
compare distributions of a variable between places
(They distort shapes to make sizes correct.)
What impressions do you get from this map?
Map Scale The ratio of map distance to earth distance,
measured in the same units
smaller scale
Sample Area Covered
Fraction Scale
Verbal Scale
World
No. America
Central U.S.
AAA Colo map
1:78,000,000
1:36,000,000
1: 4,000,000
1: 1,267,200
1
1
1
1
in
in
in
in
= 1,250 mi
= 570 mi
=
64 mi
=
20 mi
larger scale
Smaller-scale shows more land area in less
detail. Used to show global patterns.
Larger-scale shows less land area in more
detail. Used on local maps.
The scale at which one analyzes an issue is critical
DIA – Only major U.S. airport built since 1980
At the national scale, why did the location of this airport make sense?
At the local scale, why was it necessary to locate the airport where it is?
Map Aggregation
Percent of 1990 pop age 25+ with bachelor's degree
Data aggregated by State
The level of
detail for
dividing a
thematic map
into
geographic
units
Ranges from
coarse divisions
(e.g., by
countries) to fine
divisions (e.g., by
zip codes)
Percent of pop age 25+
with bachelor's degree
(1990)
Note what information
is lost at higher levels
of aggregation
Aggregated
by State
(northeast
close-up)
Aggregated by County (WV, MA)
2004 Presidential Election
Red = Bush; Blue = Kerry
State results,
by land area
County results,
by land area
State results,
by population
County results,
by population
Source: M. Gastner, C. Shalizi, and M. Newman, University of Michigan
http://www-personal.umich.edu/~mejn/election/
2004 Presidential Election
Red = Solidly Bush (70% +)
Purples = divided … redder = Bush majority; bluer = Kerry majority
Blue = Solidly Kerry (70%+)
By land area
By population
Source: M. Gastner, C. Shalizi, and M. Newman, University of Michigan
http://www-personal.umich.edu/~mejn/election/
Spatial Thinking
(Phil Gersmehl, Research in Geographic Education, 2006)
Pattern Analysis: Density vs. Dispersion
Which square mile has the higher density, (a) or (b)?
Various Pattern Arrangements
What phenomena could explain the
patterns shown in A, B, and C?
Quick mapping activity –
example of identifying changes
in a spatial pattern, reasons
for the changes, and
consequences of these changes
With a partner, map the
following (on the same map):
1. Use a diamond symbol  for
the cities in which there was a
Major League Baseball team in
1952 (16 teams).
2. Use a different symbol for
the locations of MLB teams in
2007 (30 teams).
Coors Field
Connections
What kinds
of things are
symbolized
by lines on
this map?
Combination of climate, agriculture, and
industry explains population density patterns
Where are some patterns that illustrate this?
Denver metro area
How does this map
illustrate the aura or
zone of influence for
Denver?
How are hierarchies
symbolized on this
map?
For which kinds of
services does
Denver’s aura extend
beyond this map?
Where could
you define a
region of
“Elvis-lovers”?
Where are the
exceptions?
Where are the
outliers?
Compare the
Pacific coasts
of North and
South America
Which places
have analogous
climates?
Middle & South America
Agricultural Regions (left) and
Population Density (below)
Spot any spatial
correlations?
An example of the importance of spatial thinking
Christian
TURKIC (Altaic Language
Diversity,
Family)
exceptions,
and edges
can make
for
interesting
IRANIAN (Indo-European
case studies
Language Family)
or
SEMITIC
(Afro-Asiatic
examples
Language Family)
Turkey
Knowledge of cultural
regions, boundaries, and
transitions is necessary for
understanding conflicts
Syria
Iran
Jordan
Iraq Ethnic
Groups
Saudi
Arabia
Kuwait
Iraq’s population is 29 million: sixty percent are Shi’a Arab, mostly in the south.
Sunni Arabs are concentrated in the center (western Iraq is sparsely populated).
Over 4 million Iraqis in northern Iraq are Kurdish. Baghdad is a transition zone.