The document provides an overview of mapping data types, sources, and visualization techniques. It discusses two primary data models for maps: raster and vector data. Raster data consists of cells with discrete values arranged in rows and columns, while vector data uses coordinates to represent points, lines, and polygons. It lists several sources for mapping data, and describes common map types like choropleth, proportional symbol, dot density, and cartogram maps. Finally, it mentions some file formats and mapping software/tools.

1. Mapping Your Data Christopher Martin [email_address]

2. About Me Geography Major Computer Science Minor

3. Outline Data Types/Models Data Sources Map Types Demos

4. Tools of the Trade Cartographic Software ArcMap Other (uDig, QGIS, GRASS) “ Mapping” Libraries/Tools Google Earth, Google Maps, OpenLayers

5. Data Models Two primary data models used when making maps Raster Data Vector Data

6. Raster Data Consists of discrete cells (think graph paper) Each cell has a discrete value Occur in rows and columns Examples Images (all image types) DEM

7. Vector Data Each position is represented by coordinates Coordinates are connected to form lines or polygons Points, lines and polygons are then used to represent geographic features Examples Shapefile

8. Points, Lines, Polygons

9. Data Sources US Census Bureau Not just population data Generalized Boundary Data ESRI TIGER/LINE NED Data FEMA Q3 Flood Data USGS SEAMLESS Distribution

10. Data Sources (cont’d) NYS GIS Clearing House Membership required Wide variety of data CUGIR NYS and National data Free, huge variety CIGAR Worldwide Elevation Data Columbia University EDS Electronic Data Service

11. Data Sources (cont’d) Geography Network Aggregates data from different providers Online Map Server Available

12. Data Quality Meta Data Data about the data All legitimate providers will provide this Available for download or online viewing

13. Map Types Thematic Maps Not reference maps Four main types Choropleth Map Proportional Map Isarithmic Map (contour) Dot Map

14. Choropleth Map Shaded Areas The “color” of the shade varies based on measurement of our variable

15. Isarithmic Map Also known as Contour Maps We draw lines to connect separate variables that have the same value

16. Proportional Symbol Map Uses symbols The size of the symbol varies according to the variable

17. Dot Density Map Uses dots Size is uniform, but the concentration represents changes in the variable

18. Cartograms Are NOT maps Area is not preserved Area of the geographic regions varies by variable Two primary types Area Area gets larger or smaller depending on the variable Distance Nodes or places can be closer or farther depending on realtive distance

19. Cartogram

20. File Formats Shapefile A collection of points, lines and polygons Tabular data values assocated with each DEM Raster data, each cell represents elevation Comes in different resolutions

21. Demo Time! Gathering Data Converting Data Geocoding Getting Data Into Arc Map Making a Map ArcMap Google Earth Google Maps/OpenLayer