Lecture 3: Types of Data in GIS

Handouts:

Selections from Marc van Kreveld, Geografische Informatiesystemen, 1996.

Buttenfield, B.P. Treatment of the Cartographic Line. Cartographica, vol. 22(2): 1-26, 1985.

An example using Watershed data: http://maps.epa.gov:10000/iwimap/

Some categories seen in this example (you will find that Geographers like to categorize.)

 

Stevenís Levels of Measurement

Note which transformations preserve the information in a measurement.

 

Types of maps:

Topographic: detailed representation of topography

Thematic: communicates distributions, etc.

Line maps vs Photo maps

Data Models:

Data models will appear in different layers; Layers can be combined visually, or by explicitly calculating their overlay.

 

Types of spatial objects as represented in a GIS

Objects have attributes (names or values), and reflect some entity in reality.