The US Census provides an incredible wealth of data but it’s not always easy to work with it. In the past, working with the tabular and spatial census data generally meant downloading a table from FactFinder and a shapefile from the boundary files site and joining the two, perhaps in a GIS system. These files could also be handled in R but getting the data, reading it into R and, in particular, merging tabular and spatial data can be a chore. Working with slots and all the different classes of data and functions can be challenging.
A recent interesting post on stackoverflow by Claire Salloum prompted me to revisit this issue in R and I’ve definitely found some valuable new packages for capturing and manipulating Census data in R.
Great post explaining how to wrangle and map census data in R.
Very handy tutorial for hexbinning directly in PostGIS.
Short version: In QGIS, use the Create grid layer function in the MMQGIS plugin to create the hexbins. Then import this layer into PostGIS and use the ST_Contains function to join your points spatially to the hexbins. Voilà.
Google Summer of Code 2015 is coming to an end today. I’ve been mentoring Deepak over the summer, who built an awesome prototype to bring the enviroCar data into the LOD cloud.
If you were always wondering how machine learning works, but didn’t dare to ask.
CartoDB’s Chris Whong wrote this super-handy data exporter for NYC PLUTO data, the city’s land use and geographic data set. Lets you select geographic and thematic subsets of the data and either download them in various formats, or directly load them into your CartoDB account.
The folks over at CartoDB have invited me to talk a bit about how I use their platform when I teach Free and Open Source GIS. Their CartoCamp Edu event will be held on August 21st at NYU.
This protection is important for everyone. It’s easy to see how encryption protects journalists, human rights defenders, and political activists in authoritarian countries. But encryption protects the rest of us as well. It protects our data from criminals. It protects it from competitors, neighbors, and family members. It protects it from malicious attackers, and it protects it from accidents.
Security guru Bruce Schneier explains why encryption is important. Worth a read.
I’ll be mentoring Deepak Nair over the summer through Google’s Summer of Code program. He will finally add a full-fledged Linked Open Data layer to enviroCar, including a SPARQL endpoint and automatic interlinking with external data sources.
52°North has been accepted as a mentoring organization for Google Summer of Code again. Take a look at their project ideas page if you think of applying.
Very neat trick to execute SQL queries against a PostGreSQL (or PostGIS, as in my case) database directly from Sublime Text. Now I just need to figure out how to automatically refresh the results file in Sublime after a query.