Post on 17-Jan-2016
INTRO TO SPATIAL DATA ANALYSIS
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Content
Modeling our World Modeling our World with GIS Spatial Questions vs. Attribute Questions Results Terms to Know
Coordinate Reference System (CRS) Geographic Coordinates Projection
Shapefile Layer
QGIS 1.8 LisboaJOU-1526 Computer Assisted Reporting
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Modeling our World
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We describe any element of our world in 2 ways:
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Modeling our World with GIS
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A Geographic Information System (GIS) links location data and attribute data
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Spatial Questions vs. Attribute Questions
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In a GIS data can be queried spatially or by attributes:
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Results
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Terms to Know
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Coordinate Reference System (CRS) Geographic Coordinates Projection
Shapefile Layer
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Terms to Know – Coordinate Reference System
Geographic Coordinates 0° (Degree) Latitude Equator 0° (Degree) Longitude Greenwich (GB) Ottawa: 45°N, 75°W
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NEVER MEASURE IN DEGREES!!
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Terms to Know – Coordinate Reference System
Map Projections Method to represent
the surface of a sphere(3D) on a plane (2D)
Coordinates are now in measurement units like meters, km, feet, miles,… JOU-1526 Computer Assisted Reporting
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Terms to Know – Coordinate Reference System
Projected [m] Unprojected [degrees]
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Projections always distort surfaces!
Different projections based on location and purpose of map
Terms to Know – Coordinate Reference System
• Shape• Area• Direction• Size
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Terms to Know - Shapefile
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File containing information about the shape of objects, their attributes and locationsShape
Polygon
Line
Point
Location
Geographic Coordinates in Latitude / Longitude
Projected Coordinates in Measurement Units
Address
Attributes
Any kind of detail about the feature: height, length, name, color, etc.
File_Name.shp
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Terms to Know - Layer
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Represent the World as Layers of Information or Themes
Layers are saved as Shapefiles
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QGIS 1.8 Lisboa
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TOC = Table Of Contents
Shapefiles and Tables show here as so called “Layers”.
Main Window or Canvas
Data display area.
Coordinates and ScaleCoordinate Reference
System (CRS)
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References
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Map Projections: http://egsc.usgs.gov/isb/pubs/MapProjections/projections.html
http://www.electoralgeography.com/new/en/countries/c/canada/canada-legislative-election-2011.html
http://datajournalism.stanford.edu/ http://votecompass.ca/