Intro to Geospatial Data Science Keely Roth, PhD Sacramento Women in Data Science August 23, 2016

We’ll cover… Spatial data basics Cartographic principles Ways to get started Resources

Why geospatial data science? Maps are powerful tools for visualizing and analyzing. https://tecnilogica.carto.com/viz/56e702fe-4693-11e5-8f79-0e853d047bba/public_map

What makes data spatial? attributes associated with a location arise from a spatial process can be an object or a field http://blog.rtwilson.com/wp-content/uploads/2012/01/SnowMap_Points.png http://freegeographytools.com/wp-content/uploads/2007/05/terrain-merge.jpg

Spatial Data Basics More than just where it is…

Key Concepts For working with spatial data Spatial Reference Systems: Geographic Coordinate Systems Key Terms: Geoid Ellipsoid Datum http://tinyurl.com/znqvvjn https://www.e-education.psu.edu/natureofgeoinfo/sites/www.e-education.psu.edu.natureofgeoinfo/files/image/long_lat.gif http://www.navipedia.net/images/thumb/2/29/Datum.png/400px-Datum.png

Key Concepts For working with spatial data Spatial Reference Systems: Projected Coordinate Systems http://tinyurl.com/znqvvjn http://www.progonos.com/furuti/MapProj/Normal/CartDef/MapDef/Img/devSurfaces.png

Key Concepts For working with spatial data https://2015.foss4g-na.org/sites/default/files/slides/Intro%20to%20Spatial%20Data%20Analysis%20in%20Python%20-%20FOSS4G%20NA%202015.pdf

Key Concepts For working with spatial data https://2015.foss4g-na.org/sites/default/files/slides/Intro%20to%20Spatial%20Data%20Analysis%20in%20Python%20-%20FOSS4G%20NA%202015.pdf

Types of Spatial Data Analysis What can we do with spatial data? ESRI: Spatial Analysis

Cartographic Principles Just because you can map it, doesn’t mean you should…

Good Cartography: Map Elements What does my map need on it? Slocum’s Map Elements: frame and neat line mapped area inset title & subtitle legend data source scale orientation https://saylordotorg.github.io/text_essentials-of-geographic-information-systems/s13-03-cartographic-design.html

Good Cartography: Design principles How do I design something people want to look at? Visual Contrast Legibility Figure-Ground Organization Hierarchical Organization Balance ESRI MAP DESIGN

Good Cartography: Guiding principles What to keep in mind when making maps BEFORE DURING AFTER Should I map this? Who is going to look at this map? What is the key message (yes, just one) this map will carry? What spatial representation of my data will best highlight the information I want to present? What colors & symbology emphasize my map’s information? What is the appropriate spatial scale for my map? Am I showing the data honestly? Is my map easy to understand? Is everything I’ve mapped essential?

Getting Started How can I make a map and analyze my spatial data?

Many ways to make a map (& analyze it) Choices, choices, choices.. Platform: Desktop, Web, Mobile Software: Commercial v. Open Source Map Interface: Static v. Dynamic

Typical Data science Tools: R & Python Packages: sp rgdal maps maptools rgeos raster ggmap Libraries: shapely GDAL/OGR pyQGIS pyshp pyproj GeoPandas PySAL Rasterio Fiona cartopy matplotlib http://spatial.ly/2013/12/introduction-spatial-data-ggplot2/ http://wrobstory.github.io/2013/04/python-maps-choropleth.html R map top: http://spatial.ly/2013/12/introduction-spatial-data-ggplot2/ R map bottom: https://www.r-bloggers.com/mapping-san-francisco-crime/ Python map top: http://wrobstory.github.io/2013/04/python-maps-choropleth.html Python map bottom: http://matplotlib.org/basemap/users/examples.html https://www.r-bloggers.com/mapping-san-francisco-crime/ http://matplotlib.org/basemap/users/examples.html

WEB-BASEd TOOLS: Google Earth Engine development in JavaScript or Python many data layers available

WEB-BASEd TOOLS: Openstreetmap (& friends)

http://xkcd.com/1688/large/

Resources GENERAL KNOWLEDGE SOFTWARE/TOOLS Geospatial Analysis (e-textbook by de Smith, Goodchild, Longley) 13 Free GIS Software Options Open Source Geospatial Foundation A gentle introduction to GIS R packages for spatial data analysis Coordinate systems, map projections, and geographic transformations (ESRI) Spatial.ly: Visualisation, Analysis and Resources in R Intro to Spatial Data Visualization in R Geospatial Python GIS in Python Intro to Spatial Data Analysis with Python (YouTube) How Mapbox Works CartoDB Workshop by UCLA Mapshare Intro to Google Earth Engine API