[uf-discuss] geo - accuracy of coordinates

[Kevin Marks]

On Oct 2, 2006, at 3:16 PM, Chris Casciano wrote:
> You could outline any territory as a series of geos if the need ever  
> arose. But I'm still not clear how we've gotten here. If I want to say  
> something is in Ireland, or Mexico City or somewhere in the Alps I'd  
> tag it as such. I thought the original issue of accuracy was one of  
> precision (either via tool measurement or in human recollection).
>
> Not one of being able to define a "geo" that accurately represents the  
> floorplan of Yankee Stadium or the whole of Antarctica but of  
> accurately reflecting if a designation was accurate enough to make a  
> determination if a specific seat in yankee stadium, "somewhere in the  
> bleechers", or just "near the stadium as i was walking around before  
> the game" or "i need to mark the bronx somehow so left me zoom out and  
> drop a marker from the 50k foot view"

http://flickr.com/map/?&tag=yankeestadium&fLat=40.828081&fLon= 
-73.920821&zl=7

Notice that the yankeestadium tag shows various usages here - the  
ambiguity between where the photo was taken from and what it was taken  
of.

You could probably derive a useful 'centrepoint + radius' for Yankee  
stadium from the mean and std-dev of those geolocated, tagged points.

Notice that the URL I used above has 6 digits of latitude and longitude  
(a supposed precision of ~ 10cm), but a zoom-level parameter to express  
the actual display I wanted to convey.

However, what you see is dependent on the size of your browser window,  
as the zoom-level is defined based on pixel-size, not window width.