Free online GIS tools: An introduction to GeoCommons

Read my tutorial on how I created the pedestrian map with GeoCommons. Read on for an introduction to GeoCommons and online GIS tools.

GeoCommons, like Google My Maps and Earth, is part of the “poor man’s GIS package.” It’s another tool that provides (few) of the functions that desktop GIS software offers. But it excels at making simple and somewhat complex maps.

I first used GeoCommons over a year ago. I started using it because it would convert whatever data you uploaded into another format that was probably more useful. I mentioned it in this article about converting files. For example, if you have a KML file, you can upload it and export it as a shapefile for GIS programs, or a CSV file to load into a table editor or spreadsheet application.

After creating the Chicago bike crash maps using Google Fusion Tables, I wanted to try out another map-making web application, one that provided more customization and prettier maps.

I found that web application and created a version of the bike crash maps, with several other data layers, in GeoCommons. I overlaid bike counts and bikeways so you can observe some relationships between each visual dataset. My latest map (screenshot below), created Wednesday, shows pedestrian counts in downtown Chicago overlaid with CTA and downtown Metra stations, as well as the 48 intersections with the most pedestrian collisions (from this UNC study, PDF).

Screenshot of pedestrian count map described above.

How these online GIS tools can be useful to you

I bet there’s a way you can use Google Fusion Tables and GeoCommons for your job or project. They’re extremely simple to use: they can take in data from the spreadsheets you’re already working on and turn them into themed reference maps. With mapping, you can do simple, visual analysis that doesn’t require statistical software or knowledge.

Imagine plotting your client list on a map and grouping them by age to see if perhaps your younger clients tend to live in the same neighborhoods of town, or if they’re more diverse (should you do this, keep the map private, something that you can’t do in GeoCommons – yet).

You may also find it useful if you want to create a route for your salespeople or for visiting church members at their homes. Plot all the addresses on a map, then manually filter them into different groups based on the clusters you see. With Google Fusion Tables, you can easily add a new column with the GROUP information and apply a numbered or lettered group and then re-sort.

Other things you can do in GeoCommons

• Merge tables with geography – I uploaded two datasets: a table containing census tract IDs and demographic information for Cook County I downloaded from the American FactFinder 2; and a shapefile containing Cook County census tracts boundary information. After merging them, I could download a NEW shapefile that contained both datasets.
• Make multi-layer maps
• Symbolize based on frequency/rate
• Convert data – This is by far the most useful feature. It imports “shapefiles (SHP), comma separated values (CSV), Keyhole Markup Language (KML), and GeoRSS” and exports “Shapefile, CSV, KML, GeoRSS Atom, Spatialite, and JSON” (from the GeoCommons user manual).

Read my tutorial on how I created the pedestrian map with GeoCommons.