How is it done ?

[soiseven]

I see that every "hole in the wall" bar NAME, minimart, 7/11, ATM and... and....is marked with accurate co-ords.

 

Please..how is it done.?

[+bittsen]

I see that every "hole in the wall" bar NAME, minimart, 7/11, ATM and... and....is marked with accurate co-ords.

 

Please..how is it done.?

 

There has to be a place where companies can submit their information to be included in the maps. I think I remember seeing it somewhere and they charged a fee for the listing. For an additional fee they could have their own icon added.

 

(This was when I was checking into maps for my old Magellan)

[MtnHermit]

Good chance the Census Bureau has this data, they have all the roads, might as well have this data too. Next year they'll have you and me too. The 2010 census takers will have GPS data loggers, so when they count you they'll have your position too. Big Brother!!!!

 

Only the eastern hill country of Kentucky will be omitted.

[+alanfreed]

There are companies out there that do nothing but sell specialized mailing lists. Our company had a project years ago where we purchased a list of all churches in North America. Granted, it was riddled with errors, but it was a good starting point for what we needed to do. These companies can supply address data for virtually any field of business nowadays.

 

Having said all of that... I think the original poster is wondering how they get accurate lat/lon data for each of these places, as if some dude walks around to every minimart in the country and marks a waypoint. I don't know the answer, but I would have to assume that however they manage to come up with accurate (or reasonably accurate) address coordinates is how they come up with these point of interest coordinates. They're likely just using the addresses supplied to them, and using their address pinpointing mechanisms to create those points.

[+Red90]

IME, the coordinates are usually not accurate for POIs.....

[+StarBrand]

I see that every "hole in the wall" bar NAME, minimart, 7/11, ATM and... and....is marked with accurate co-ords.

 

Please..how is it done.?

Not usually all that accurate. Within 200 to 300 feet usually though - close enough. All it really takes is the coordinates for the nearest intersection of streets in either direction - then based on the address - you can approximate how far down the block to go. Its called geocoding. Translating street addresses into coordinates.

[John E Cache]

OOPs misread OP. I was was going to point to the USGS name service, but that doesn't do commercial names.

Edited November 18, 2009 by John E Cache

[+DavidMac]

I see that every "hole in the wall" bar NAME, minimart, 7/11, ATM and... and....is marked with accurate co-ords.

 

Please..how is it done.?

Not usually all that accurate. Within 200 to 300 feet usually though - close enough. All it really takes is the coordinates for the nearest intersection of streets in either direction - then based on the address - you can approximate how far down the block to go. Its called geocoding. Translating street addresses into coordinates.

 

Wikipedia has a bit more info on how this is done. The software takes the street address and estimates where it should lie between two intersections. To quote their example:

 

Take for example: 742 Evergreen Terrace

 

Let's say that this segment (for instance, a block) of Evergreen Terrace runs from 700 to 799. Even-numbered addresses would fall on one side (e.g. west side) of Evergreen Terrace, with odd-numbered addresses on the other side (e.g. east side). 742 Evergreen Terrace would (probably) be located slightly less than halfway up the block, on the west side of the street. A point would be mapped at that location along the street, perhaps offset some distance to the west of the street centerline.

 

I used to know someone who (in the 1980's) helped digitize the data that is still used to geocode many of the street adresses in our county. It was originally used to help 911 determine where to send emergency vehicles when responding to call. It also had census implications but I never got the details as to how.