Sunday 9th June, 2013
2:30pm to 3:00pm
Foursquare needs quality place data to power its geocoding engine to ensure the best recommendations. When someone searches for best coffee in Brooklyn, a simple venue to place point or venue to place bounding box search can result in venues in Manhattan and Jersey City overwhelming the results for Brooklyn. To improve recommendations, they’ve created an authoritative source of polygons around a curated list of places. This gazetteer of non-overlapping polygons provides more relevant results than simple point geometries.
This work is based on foursquare checkins, geocoded photos from Flickr, and an extended version of Natural Earth. The quattroshapes technique calculates the dominant place ID for a given area based on heterogeneous inputs and supplemented geometries with open government data. The quattroshapes code and resulting polygons are licensed under CC-BY.
Geocoding can be the hardest part about going open source - and geo and reverse geocoding is even harder. Reverse geocoding reports the gazetteer place for a latitude and longitude map location or address string and is useful when source data needs to be normalized. This new polygon gazetteer data is used in TwoFishes, the coarse splitting geocoder (and reverse geocoder) written in scala from David Blackman at foursquare.
Map geek & cartographer @stamen, formerly @washingtonpost, @nationalgeographic. Check out NaturalEarthData.com! Views my own, RT != +1. Redacted: @nvkelso.
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