GeoNames Home | Postal Codes | Download / Webservice | About 

GeoNames Forum
  [Search] Search   [Recent Topics] Recent Topics   [Groups] Back to home page 
[Register] Register / 
[Login] Login 
US postals with centers off by more than 10 miles  XML
Forum Index -> Postal Codes
Author Message
denimboy



Joined: 03/01/2018 01:54:38
Messages: 5
Offline

Hi,

I found 2,65 postal code which I am sure are more than 10 miles off from where they should be. My source of truth is the ZCTA shapefile published by the US federal government. https://www.census.gov/geo/reference/zctas.html

My method was to create centroids for each postal then join to the geonames postal data via the postal code. I calculated the distance from the geonames centroid to the ZCTA centroid using the haversine formula and output the postal, zcta_lat,zcta_lon if the distance was more than 10 miles.

Enclosed please find the postals which should be corrected. File is a CSV in postal,latitude,longitude format.

Thanks,

D

 Description csv of postal, correct lat, correct lon. The data in this file was computed from public domain data [Disk] Download
 Filesize 40 Kbytes
 Downloaded:  716 time(s)

marc



Joined: 08/12/2005 07:39:47
Messages: 4044
Offline

ZCTA is far from reliable, this was actually our first source 12 years ago. I hope we have improved since.

Best Regards

Marc

[WWW]
denimboy



Joined: 03/01/2018 01:54:38
Messages: 5
Offline

Hi,

> ZCTA is far from reliable, this was actually our first source 12 years ago. I hope we have improved since.

The geographic offerings from the US government have improved quite a lot in the last 12 years as well.

Anecdotally I have had zero "postal in wrong location" reports since making these adjustments and I used to get 1-2 per week when I relied on geonames postal data alone.

I sincerely hope you reconsider checking these adjustments out.

Thanks,

D
 
Forum Index -> Postal Codes
Go to:   
Powered by JForum 2.1.5 © JForum Team