Entity resolution for venues and other geo locations

Question

Say I want to build a check-in aggregator that counts visits across platforms, so that I can know for a given place how many people have checked in there on Foursquare, Gowalla, BrightKite, etc. Is there a good library or set of tools I can use out of the box to associate the venue entries in each service with a unique place identifier of my own?

I basically want a function that can map from a pair of (placename, address, lat/long) tuples to [0,1) confidence that they refer to the same real-world location.

Someone must have done this already, but my google-fu is weak.

Answer 1

Yes, you can submit the two addresses using geocoder.net (assuming you're a .Net developer, you didn't say). It provides a common interface for address verification and geocoding, so you can be reasonably sure that one address equals another.

If you can't get them to standardize and match, you can compare their distances and assume they are the same place if they are below a certain threshold away from each other.