TIGER and OSM, 12 years later

More than a million people have edited OpenStreetMap (OSM) for the last 15+ years (and I am one of them). That means we have a map that is fantastic to look at in many places, like here at Epcot Center in Florida, USA.

OSM mappers love to highlight great and impactful mapping accomplishments like Map Kibera and the massive campaign followingthe devastating Typhoon Haiyan. And rightfully so, OSM shines where no other map can because it is open and free.

There is also a shadow side to OSM, areas that nobody seems to care about. You could argue that this doesn’t matter. OSM is, in a way, subject to the laws of supply and demand. Where a better map is needed, one shall be created.

But OSM has never really been about that. Most volunteer OSM mappers create the map with highly altruistic motivations and a sense of “personal but shared need”. Because of this, I don’t believe it’s too much of a stretch to posit that Linus’s Law — “Given enough eyeballs, all bugs are shallow” — applies to OSM as well. If you point out where OSM could use some love, mappers will extend that love and make the map better.

My deep faith in that power of a map-loving OSM community has inspired me to build several tools over the years aimed at guiding mappers to forgotten places in OSM. The best known is probably MapRoulette, a website that dispenses micro-tasks for mappers to solve.

A lesser known tool I built some years ago when I was at Telenav looking into the quality of the OSM road network in the USA is the TIGER Battlegrid.

The original TIGER Battlegrid, screenshot from the OSM wiki

The TIGER Battlegrid would show an OSM map overlaid with colored cells. The brighter the cell, the worse the quality of road alignment. It was called the TIGER Battlegrid because 1) The quality analysis was done by comparing OSM data with the then-current 2012 Census TIGER road network data, and 2) because OpenStreetMap in the United States got started by a huge import of TIGER road network data in 2007–8.

Animation showing TIGER data import, from the OSM wiki

The quality of that 2007 TIGER data was very poor in places and a lot of fixup was needed, something the community picked up quickly in many places. But the United States is a very big place and many areas remained where no fixup was done. So I cooked up the TIGER Battlegrid to point mappers to areas that still needed fixing.

The Battlegrid was popular and many places received some much needed mapping love. But I moved on to other projects, and at some point the Battlegrid went offline and, due to me neglecting to properly document the project, was lost.

People kept asking me about it and it made me sad to have to tell them no. Even though many data layers and tools are now available to inspect and detect outdated roads in OSM (see iD screenshot below), the Battlegrid struck a chord with people.

The OSM iD Editor with a colored overlay showing where mismatches exist between current TIGER roads and OSM.

And we are still far from done cleaning up after the 2007–8 TIGER import, as this image recently posted to the OSM Slack channel demonstrates:

Bad TIGER roads. Screenshot uploaded by Richard Welty, Road data ©OSM, aerial imagery ©Bing

So, I spent a bit of time recreating something close to the original Battlegrid, and you can preview it here. It only covers Colorado for now, it lacks some of the functionality of the original (notably, you can’t mark cells as done). And last but not least, the project in its current state is extremely hacky — but at least, it’s documented.

The current Colorado Battlegrid

Please give it a spin and let me know your feedback. I would love your help making it better.

Published by Martijn van Exel

Geospatial omnivore. OpenStreetMap - Open Data

One thought on “TIGER and OSM, 12 years later

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: