GEOG 581: Cartography Design

WEEK-02

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Session ONE:

Representation: The First Perspective  of Maps

"Representation" Perspective

The earliest and intuitive goal of maps is to "represent" our world.

 

Oldest Map Marked "America"

http://news.nationalgeographic.com/news/2003/06/0619_030619_americamap.html

 

1896  Map of Taiwan (Formosa) (From the Scottish Geographical Magazine. Published by the Royal Scottish Geographical Society and edited by James Geikie and W.A. Taylor. Volume XII, 1896.)

Data/Image Source: http://www.chinapage.com/map/ancient/taiwan1896.html

 

San Diego Maps (1850)

from The Journal of San Diego History Spring/Summer 2000, Volume 46, Number 2-3
The Pantoja Map of 1782 and the Port of San Diego: Some Answers Regarding the International Boundary in the San Diego-Tijuana Region by Jorge A. Vargas

http://www.sandiegohistory.org/journal/2000-2/pantojaphotos.htm

 

San Diego Historical Map compare to the 2002 Aerial Photos (San Diego).

 

Representation: 

Step 1: Level of Measurement:

(Nick Christman (1998) Rethinking Level of Measurement for Cartography).

In the classical view, measurement discovered the numerical ratio between a standard object and the one measured.

What time is it?  The official U.S. Time: http://www.boulder.nist.gov/timefreq/  (A standard object --  Time Clock)

In the new "representational" school: "Measurement is ... a unique and reciprocal correspondence is established between all or some of the magnitudes of a kind and all or some of the numbers, integral, rational, or real ...

(Measurement should not only focus on "numbers"...   The needs from Social Science:  example: How to measure the "happiness" ? )

Stanley S. Stevens' paper in Science (1946) on the subject of measurement played a formative role in a large movement towards a quantitative methodology in the social science.

 Scale  Basic Empirical Operations  Mathematical Group Structure  permissible Statistics (invariantive)
Nominal  Determination of equality  x' = f(x) (one-to-one)  Mode
Ordinal  Determination of greater or less  x' = f(x) (monotonic increasing)  Median
Interval  Determination of equality of intervals or differences  x' = ax + b  Mean
Ratio  Determination of equality of ratios  x' = ax  Coefficient of variation

Nominal: grouping or categorization.  (no ordering, each group is equally important)

bulletGender:  Male / Female
bulletLanduse: Agriculture / Residential / Industry Zone / Business Areas
bulletCurrency Type:  US Dollar vs. Euro Dollar (?)
bulletMODE: The biggest group in the category.  (Best selling CD album).

Ordinal: ordering (ranking) (high, medium, low)

bulletInterstate Highway, City roads, Trails
bulletHomeland security status:  RED, Orange, Yello, Guarded, Low.

Homeland Security Advisory System

Interval: an ordering of the data plus an explicit indication of the numerical differences between two categories (Slocum textbook).

bulletArbitrary zero point (ratio of two interval values cannot be interpreted correctly):  SAT score 800 vs. 200. (4 times better than?)
bulletElevation (changing "arbitrary zero" with the change of sea level).
bulletFahrenheit temperature (F)

Ratio: similar to interval, but also has a absolute zero (null). 

bulletBank account balance: Zero --> null
bulletPopulation
bulletKelvin scale temperature.

 

Other Aspects:

bulletQualitative data (nominal)
bulletQuantitative data (ordinal, interval, and ratio).

 

Extension of four measurement level (Christman, 1998).

bulletNominal
bulletGraded membership
bulletOrdinal
bulletInterval
bulletLog-interval
bulletExtensive ratio
bulletCyclic ratio
bulletDerived ratio
bulletCounts  (population)
bulletAbsolute (probability)

 

What categories for  Different countries' currency?  US Dollar vs. Euro Dollar vs. New Peso

(Same measurement, different aspects:  currency exchanges, economic index, functionalities..)

 

Other extensions:

Biopolar data (a natural dividing point can be sued to divide the data into two parts:   Population change in San Diego --> positive or negative percent changes?)  Balanced data, Unipolar data.

San Diego County Census Quick Fact (U.S. Census Burea):
http://quickfacts.census.gov/qfd/states/06/06073.html

 

Level of measurement can be changed by using generalization or classification.  ( Midterm exam grading --> numbers --> higher than 60: PASS,  lower than 60: Fail)  or A, B, C, D gradings.

Step 2: Choose Symbols to represent the measurement results

 

Spatial Dimension

bullet

Discrete vs. Continuous phenomena (People (Population) vs. Temperature)

bullet

(0D, 1D, 2D, 2.5D, 3D, 4D):

 

Points symbols (zero-dimensional):  with X, Y, Z coordinate

bullet

Locations of points,  (Dot maps)

bullet

Iconic representation,

bullet

Size of point symbols (proportional symbol map)

 

Linear symbols (one-dimensional): (lines, paths)

bullet

Linear phenomena (having length, but no width?? )

bullet

Location:  from x1, y1, z1, to x2, y2, z2, to x3, y3, z3, ....

bullet

nominal lines?

bullet

ordinal lines?

bullet

Interval lines? (contour line?)

bullet

ratio lines? (snow falls? precipitation?)

bullet

Isarithmic Maps (Iso-line maps: contour lines, temperature maps, etc.)  Use linear symbols to represent 2D or 3D phenomena)

San Diego Temperature Map  http://dvl.sdsc.edu/projects/flysd/  (from UCSD)

 

Areal Symbols: (2 Dimensional):

bullet

Examples: Lakes, Regions, States,

bullet

Choropleth Maps (Population density)

bullet

Cartogram (Value by Area)

 

Choropleth Mapping:

The need for data standardization (normalization), in which raw totals are adjusted for differing sizes of enumeration units. (Administration units, like state or county boundary)

 

 

2 1/2 D Symbols (2.5 dimensional, Volume):

bullet

2 1/2 -D: a surface in which geographic location is defined by x and y coordinate pairs and the value of the phenomenon is the height above a zero point. 

bullet

lack of true Z coordinate  (replaced by the attribute values)

 

TRUE 3D symbols and objects (Three-dimensional): 

bullet

Any point on the surface is specified by four variables (X, Y, Z, and the values).

bullet

3D maps (usually mixed up with 2 1/2 maps)

bullet

Underground water quality

bullet

CO2 level in the atmosphere.

 

4D? (Temporal dimensional)

Animation (San Diego Wildfire animation) http://map.sdsu.edu

 

5D? 6D? 7D?  (Other dimension ?)

Visual Variables:

The various perceived differences in map symbols that are used to represent geographic phenomena.

bullet

Spacing

bullet

Size

bullet

Perspective Height

bullet

Orientation

bullet

Shape

bullet

Arrangement

bullet

Hue, Lightness, and Saturation

bullet

Other ? (Texture?)

Sound Variables? utilize sound to communicate spatial information  (computer error message).

Symbol vs. Mark (Mark: making up the symbol).

See page 72 (Figure 4.11) in your text book.

Can you draw a symbol using different visual variables?

Analytical Cartography (Slocum, chapter 2, page. 30).

Analytical Cartography was first defined by Dr. Waldo Tobler (1976) as the mathematical and analytical approaches for cartographic research.  Kimerling in 1989 gave a more precise definition of analytical cartography as “the mathematical concepts and methods underlying cartography, and their application in map production and the solution of geographic problems” (page 697). 

The topics of analytical cartography include cartographic data models, digital data collection methods, data standards, coordinate transformations, map projections, data interpolation, analytical generations, etc. (Slocum, et. al., 2004).  The recent development of analytical cartographic research has been energized with new tools and media, including multimedia, visualization software, web-based mapping tools, etc. 

bullet

Other title? Statistical Cartography / Computer Cartography

bullet

Analytical and Computer Cartography (book by Dr. Keith C. Clarke, 1990).

Twenty-eight years ago, Dr. Tobler wrote the following statements in the American Cartographer Journal: “the spirit of Analytical Cartography is to try to capture this theory, in anticipation of the many technological innovations which can be expected in the future; wrist watch latitude / longitude indicators, for example, and pocket calculators with maps displayed by colored light emitting diodes, do not seem impossible.  In a university environment one should not spend too much time in describing how things are being done today.” (Tobler, 1976, page 29).  Today, the development of mobile GIS and Internet GIS has provided very similar technological innovations to those described in Tobler’s article.

Emerging Analytical Cartography Research Themes:

bullet

Scientific research on data model, data structure, map elements,

bullet

raster-based data vs. vector-based data problem (similar to the physics during the 19th century. the particle and wave theories of lights were special cases of the general theory of relativity) What is the "general theory for Geographic data model"? (cited from UCGIS whitepaper by H. Moellering, etc. 2000).

 

Session TWO

Week One Question:

bullet

What are the differences between C. A. C. and Geographic Information Systems?

http://map.sdsu.edu/forum/

 

The same parts:

bullet

C.A.C. and GIS use computers

bullet

Focus on the process of geographic information

bullet

?

bullet

?

 

The differences:

bullet

CAC focus on Maps presentation and GIS focus on spatial analysis

bullet

GIS requires other components, data captures/input, data process, data retrieval, data storage,

bulletGIS focus more broad issues, such as database management (relational or object-oriented DBMS), (GPS conversion and tracking..)
bullet?

 

Challenge:  Can C.A.C. be used for spatial analysis ?  Map Visualization purpose?

Can C.A.C. has its own computing systems (input, output, storage?)

Introduction to ArcGIS software package:

ESRI:  www.esri.com

Desktop GIS software:

ArcView 3.2, 3.3  (earliest desktop GIS package, the most popular one, limited GIS analysis functions, inexpensive)

 

ARC/INFO workstation: (legacy professional GIS package, command line mode)

 

 

ArcGIS 9 Framework:  Scalable, professional GIS packages

Version: ArcGIS 8.3 --> ArcGIS 9.

 

ArcGIS 9 Desktop: (Professional, powerful GIS packages, expensive).

bulletArcMap
bulletArcCatalog
bulletArcToolbox
bulletArcScene
bulletArcGlobe
bulletArcReader
bullet http://www.esri.com/software/arcgis/about/desktop.html

Licensing (different prices for different levels of functions:  ArcView, ArcEditor, ArcInfo)

(Expensive, scalable functions for different levels of users -- ArcView, ArcEditor, ArcInfo)

 

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