Thematic Cartography

Much of the fun of modern cartography is in mapping thematic information  -  that is, data that do not directly relate to the physical landscape or navigation.  These themes could be anything:  population dynamics, weather phenomena, traffic patterns, etc.

For this unit, please focus on the following:

  • Distinguish the differences between choroplethchart-symbol, and dot maps.

  • Identify the common errors associate with choropleth maps: (1) the modified areal unit problem, and (2) normalization.

  • Identify the effects of classification schemes on representation:  quantileequal intervalgeometric, and natural breaks.


Thematic Maps

An overview of different types of maps, their strengths and weaknesses.

Choropleth Mapping

How do we deal with the variability of reporting areas? This video will touch upon some of the pitfalls involved with choropleth methods. -2:57- Modified Areal Unit Problem (MAUP) -5:11- Normalize by area. -7:49- Normalize by percent. -12:27- Dasymetric mapping.

Classification Methods

In this map we explore different ways to -paint- the same dataset. Depending on where you decide to place -class-breaks- the resulting effect can be quite different. (Note: Early in the video I mention this to be -Population Density- but later correct myself, we are looking at -Population Counts-.

Color Basics

What are the differences between RGB, CMYK, and HSB(V)? This is a brief explanation of what color means to computers, printers, and humans. Minute Markers: -2:19- Hue, Saturation, Brightness (or Value) -3:40- Remember to choose your destination: CMYK / RGB.

Intro to Symbology

Now that we've made a few maps, it is time to talk more in depth about how we can alter our data's symbology.

Coordinate Systems

The road to choosing custom projections is not paved with sundrops and lilies. It is time to start learning the nuts and bolts of coordinate systems. Minute Markers: -0:27- Geodesy, the geoid. -1:10- Ellipsoid, geographic coordinate system. -2:09- Can't effectively measure with ellipsoid. -3:21- Planar coordinate system. -3:49- Geodetic datums. -5:41- Projections.