Types of Maps Choropleth Dot Distribution Proportional Symbol Isoline Cartogram

Which map is best for “Number of Muslim People?” Which map is the worst?

Choropleth (most common) Pros Cons Hard to get details on internal areas. Too general Easy to collect Easy to map Common, easy to read/understand Can be used at almost any scale, from global to local 5 classes (colors) is ideal

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?

Around the World, 2000 Why is this a poor example of a choropleth map?

Dot Distribution (2nd most common) Pros Cons Shows how things are distributed Easy to see variations in spatial density. Harder to collect Point data Harder to map Hard for the viewer to read at smaller scales.

Proportional Symbol Map Pros Cons Combines graph with map Overlapping symbols can make interpreting the map difficult.

Proportional Symbol Map (Graduated Circle type) Size of symbol varies in relation to frequency or intensity of the mapped variable DISCUSSION: * What are some of the advantages of each of the four types of thematic maps? Proportional Symbol Map (Flow Vector type)

Isoline Pros Cons Limited use Can be confusing with a large list of points or dots. Most useful for climatic data presentation such as temperature or pressure. Easy to interpret, attractive.

Cartograms Combines a graph with a map Pros Cons Combines a graph with a map Can be difficult to interpret or find specific detailed information.

Types of Maps Assignment. In a group of two, your task is to locate four interesting maps (each a different type) and complete the four level geographic analysis on each map. In a perfect world each person would write on two maps.  The following types are in play: dot distribution, choropleth, isoline, proportional symbol and cartogram.  Do not to double-up-- one map of each type.  The maps descriptions are worth 10 points each.  Have some fun with this-- maps are out there for everything from 'bigfoot' and UFO sightings-to-infectious disease and internet usage.  You may be asked to share one of your maps with the class.