Today is another being-part-of-the-solution kind of day. We (a few colleages at Telenav were involved in this) took the output of the Battle Grid comparison we use to generate the Battle Grid cells, divided them into more and less severe cases based on the road class and amount of difference between TIGER and OSM, and created a MapRoulette challenge out of the more interesting cases. This will make it easier for anyone to help fix antiquated, bad TIGER data anywhere.
This is what a typical case would look like in MapRoulette:
Loading this case in iD, it’s plain to see that this road is mis-aligned pretty badly:
Easy to fix! Just drag the nodes that make up the misaligned way to match the aerial image:
To point out these errors, we compare TIGER 2014 against OSM data. This gets us mostly good results, but it’s not perfect. In most cases where MapRoulette will point out a non-error, the TIGER data is still wrong. This is the case in Alaska more than anywhere else, it seems.
TIGER is wrong here, even though it’s hard to see with the low resolution satellite imagery…
The number of non-errors is small enough to not be too annoying, I hope. If it is let me know, and I can see what more we can do to improve this challenge.
Not all at once
There are a lot of Mismatched Ways. A lot. Most of them, way more than 90%, are local and low speed roads, mapped to
residential in OSM when TIGER was imported. Of course, these all need to be fixed eventually, but let’s focus on the more important roads first. Based on how it goes, I will gradually add more cases.
I look forward to hearing from you about this new challenge! I am pretty excited about it!