Pelias, an Open Source geocoder based on Elasticsearch

(Josef Kreitmayer) #1

@species please have a look at that.

I have no idea how I stumbled upon it. By just clearing my downloads, and therefor looking at the documents, I found that document, that is a 2page comparison of nominatim search results and elasticsearch - results, where elasticsearch seems much more stable.

Here is a video about pelias, that is built on elasticsearch (whatever that is), and I bet you will like the first 25 seconds of the video, as they share their values : )

Offering pixelHumain's Communecter to Shareable for their Map Jam needs | Evaluating open data of cities in the United States of America
(Jon Richter) #2

There is quite a few geocoders out there, Pelias being one of the more interesting ones. Interestingly, Mapzen just opened a studio in Berlin to work on it. Mapbox’ division over here is is also working on Geocoding.

(Michael Maier) #3

The analysis shows: TF/IDF based ranking
yields more accurate results, especially for queries with unordered
address elements or only partially specified addresses.

The paper focused mainly on the difference of the results when both are feeded with unordered addresses. If the problem of unordered addresses does not exist (at at is in our excel template), Nominatim and Elasticsearch do not differ much.

And, more important, they only used addresses for the test that are present in OSM - my main conclusion from the paper for us is that Elasticsearch didn’t perform any better if the queried address isn’t present in OSM.

Btw.: I hate videos. you cannot search for it, you have to invest THE WHOLE 30min to know that there is nothing important for you :-/

So what was in the video:

They use for geocoding the following source:

  • OSM
  • OpenAddresses, we also plan to use (PD license)
  • Quattroshapes, only neighborhood data (which is CC-BY, therefore we cannot use because OSM requires PD)
  • Geonames, mainly places like villages (which is also CC-BY 3.0)

(Josef Kreitmayer) #4

Is there any possible walkaround with those other licenses?
It might seem strange, but does the OSM-geocodern not also deliver CC-BY, or is it just in general for using the coder, but not the data itself.

Licensing data aggregates
(Josef Kreitmayer) #5

5 posts were merged into an existing topic: Licensing data aggregates

(Michael Maier) #6

Quattroshapes and Geonames do NOT have house-number data in them!

• quattroshapes only neighborhoods - They are a polygon set of “Grätzls” and places
• Geonames has mainly POIs, like railway stations, parks and cities.

As they do not have house-numbers, these datasets do not help us much on our geocoding task.

(Jon Richter) #7