Transcript Cartography GEO381/550 - DePaul University GIS

Cartography
GEO381/550
Final Review
December, 2nd 2004
Choropleth map
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How it works?
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When to use; when not to use?
– Phenomenon
– Data
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Limitation? Solution to this?
Sample question…
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Which of the following data is the
most suitable for choropleth mapping?
– Temperature records at stations
– Number of hospital beds by county
– Average SAT scores by school district
– Total population by census tract
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Explain why…
Proportional symbol map
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How it works?
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When to use; when not to use?
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What is perceptual (apparent) scaling?
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What is range grading?
Sample question…
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Suppose we have two values, 6400 and
1600, that are to be symbolized and scaled
by proportional circles. The ratio of radius
of proportional circles that represent two
values would be 2:1 when absolute scaling
is adopted. What would happen to x in the
ratio, say x:1 when perceptual scaling is
adopted?
(a)
(b)
x will become larger than 2
x will become smaller than 2
Sample question…
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Suppose you have two maps in hand, whose
maps have legends shown below. From the
legends, discuss (1) data classification (2)
the location of point symbols of respective
map.
Dot density map
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How it works?
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When to use; when not to use?
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Advantage & disadvantage?
Sample question…
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Data not suitable for dot density map?
– Number of farms
– Total population
– Property tax rate
– Number of AIDS cases
Sample question…
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Suppose you are asked to make a dot
density map of corn acreage data which is
enumerated by state. When mapped in
ArcView, it didn’t turn out very well. What
would you do in order to improve the quality
of map, in particular locational accuracy?
Cartogram
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How it works?
In which way, cartogram is
fundamentally different from other
mapping techniques?
Advantage & disadvantage?
Sample question…
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In which of the following situations,
would you consider cartogram to be
an ideal choice?
– Map readers are not familiar with areas
– Data value is relatively proportional to the
size of enumeration unit
– The more value is concentrated in the
small enumeration unit
– Reference map
Sample question…
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Which of the four geometric elements
of enumeration units should be most
strictly preserved?
– Size
– Contiguity
– Shape
– Orientation (relative location, order)
Role (function) of map
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Map visualization (visual thinking)
Map communication (visual
communication)
Sample question…
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Suppose you are involved in two
different projects: One is to map 2000
Census (say spatial distribution of
racial group), and the other is to map
the volcanic process of Mt. Helena.
Discuss the roles of two maps. How
would different roles of maps affect
the cartographic process?
Visual hierarchy
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What is?
What is the psychological phenomenon
underlying visual hierarchy?
How to achieve visual hierarchy?
Color
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Spectral reflectance curve?
Three psychological dimensions?
Munsell color solid?
Color primaries for display in computer
screen?
Map design implications of
simultaneous/successive contrast?
Color
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How to promote efficient decoding of
color?
Brewer color schemata
– When you have population density data
– When you have historical economic data
(increase, decrease)
– When you have bivariate historical
economic data
Sample question…
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Discuss how
color is used to
promote visual
hierarchy in this
map
Sample question…
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Discuss color
as visual
variables in
this map
Sample question…
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How does hypsometric
tint make the use of
physical dimension of
color (hue)?
Illustrate how color
convention conflicts with
symbolical connotation
of color from this map.
Black Letter
Typography
Oldstyle
Modern
Sans serif
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Typeface classification
Black Letter
Sans serif
Oldstyle
Square serif
Modern
Sans serif
Modern
Oldstyle
Pay attention to serif and shading
Sample question….
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Suppose you have to label two distinct
features, say retail superstores, and castles
in the greater London area. Which of the
following pairs do you find the most
appropriate match respectively?
A
B
C
D
Discuss the use of type form (italics,
spacing, case) in this map
Final
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December 13th Monday
Here at 7:00-9:00 pm
Remember that extra point will be
given to those who make a significant
progress relative to midterm
Final project presentation
– Dec 7 and 9
– Attendance will be taken