[Talk-GB] OpenKent, OSM coverage estimation

[TimSC]

On 08/06/11 15:58, Richard Fairhurst wrote:
> TimSC wrote:
>    
>>
>> While this this strictly true it is sometimes hard to associate
>> external records with specific OSM objects. Some importing of reference
>> and ID numbers makes this easier.
>>      
> It's only hard because no-one's yet built a tool to do it.
>    
That is a feature I added to my openkent based website.

> stuffing OSM with every single id of every single
> dataset that might want to link to it is self-evidently _not_ the way to do
> it.
>    
Straw man. I said "some" id numbers not "all" id numbers - obviously 
they should only be added when appropriate.

> It isn't as complex as you'd think. You could provide an OSM service which
> ensures some degree of id memory. Alternatively, you could provide a way of
> fuzzy matching without ids ("the chemist around 52.9346, -1.87639").
That's what I do in my tool.

> If only we had more people who were prepared to pull their boots on and
> actually do stuff :(
>    
It's already done, by me. I use a XAPI request to get nearby possible 
hits, then sort by distance, generate a web page and let the user select 
the correct one. Example: 
http://toolserver.org/~timsc/locateservices/pharmacy/nearby.php?id=ph_FKH43

> As a Produced Work, yes, you can - no matter whether OGL is compatible with
> ODbL+CT. ODbL allows you to make a Produced Work from a Collective Database.
> That's right at the top, in 1.0, in the definition of Produced Work.
>    
Sigh. No. A collective database is only one narrow aspect of license 
compatibility. If I were to correct proprietary data based on OSM data 
and publish it as a propriety produced work, it would not be respecting 
the share alike aspect of ODbL. Therefore not every license is 
compatible with ODbL in creating "produced works" in the general case. 
Also, ODbL would not be compatible with the CC-BY-ND license in creating 
produced works. The same might apply to OGL data you planned to release 
the produced work as CC0.

> If I'd wanted to make the West Oxfordshire Green Travel Map from OSM data, I
> know that the incomplete areas would have been mapped if I'd asked. (As it
> happens, they have been done since, independently.) But completeness wasn't
> the problem.
>    
That is a strange argument - completeness isn't a problem because it 
could be mapped in the future? What if I want a UK complete map now? 
That is not an unreasonable request (for some features anyway). Some 
users obviously want UK complete mapping. I would imagine some users 
want a global data set. Not every user is local.
> Much of this is another Simple Matter of Programming. We need to make it
> easier for people to bring data in manually and carefully, than to blindly
> trace or import. We need to make it easier for people to contribute by
> annotating map tiles and imagery. I'm doing my bit. Why not help?
>    
I agree broadly speaking. But is that suggestion aimed at me? Can you 
stop suggesting stuff I already do? Have a look at the export looks on 
my openkent page - for helping the user find missing features, etc.

> OSM's UK countryside coverage is _outstanding_, better than
> anything except OS Landranger/Explorer,
>    
It is ridiculous to claim that OSM's UK countryside is outstanding! OS 
Mastermap is outstanding. OSM doesn't come anywhere _remotely_ near 
that. The first example I could find after 20 seconds of looking:

http://tools.geofabrik.de/mc/?mt0=mapnik&mt1=ossv&lon=-2.70484&lat=55.34008&zoom=13

Streetview far exceeds OSM here (and for more than half the country) - 
and Landranger is even better than Streetview for countryside mapping. I 
would describe OSM countryside mapping as "moderately good in very 
limited areas" - and outside that as "rubbish" - I may as well be 
navigating with a blank piece of paper as a map.

If you can't even recognize the scale of what needs to be done to 
produce an outstanding map, I guess I should not surprised you can't see 
the benefits of well conducted imports and tracing.

You say footpaths are pretty good in some areas. But there are other 
features that are hard to survey, like streams - which is what I was 
talking about. The countryside contains many private areas and you are 
saying they should be blank? Unless you (and others) routinely get 
permission to survey private land? (Not a bad idea actually.) Those 
private area and inaccessible areas are still expected to appear on 
walking maps by normal users.

> It's basically only helpful if you presume that Semantic Tourist (or
> whoever) is incapable of drawing the geometries themselves.
Umm.... You asked for successful data imports. I give you a list. You 
now say they could have been achieved using alternative means. Be that 
as it may, that is irrelevant to if imports were successful - which is 
what we are talking about.

> Even if true, your attentions would be better spent improving either
> our tools or our documentation so that not just Semantic Tourist, but a
> million mappers the world over, are empowered to map for themselves.
>    
Saying my time would be better spend elsewhere is, again, irrelevant as 
if it the import was successful.


> Again, trying to remain polite, but I'm afraid I've spoken to so many people
> in the OSM London community who have found your "mapping" in South London a
> genuine hindrance, that I find it difficult to see any value in it for the
> community.
I don't mind constructive criticism. UrbanRambler seems to have found it 
useful and he has done more than most for London mapping. Can you name 
some specific mappers who was hindered and say how it prevented them 
contributing? Has London mapping suffered long term harm? Evidence 
please? People I talk to face to face have always been supportive of 
what I do - except people who are anti imports on the mailing lists. The 
bottom line is if my tracing was so harmful, it would have been 
reverted. It wasn't but instead it was used as a basis for the existing map.

> This exact thing (albeit
> import rather than tracing) has happened in Ottawa, where an irresponsible
> importer has decided, without any foundation, to remove their trivial
> contribution using ODbL+CT as a pretext.
I would appreciate it if you stopped trivializing peoples input. If it 
was really trivial, it would not have any impact if they did not 
relicensed. And do you have any evidence that this user refusing ODbL+CT 
was a "pretext" and not a well thought out position?

> People on talk-ca are, quite rightly, furious that
> someone has taken it on themselves to delete the community's work.
If it was "the community's work" they would have total control. Since it 
was a derived work, it is not entirely theirs.

> The rural road names look seductively helpful but aren't: IMX
> very often no-one actually calls the roads by those names, whereas at other
> times locals will use a name not recorded on Locator.
Is it the road name or isn't it? I suspect the council would use the 
name if they wanted to refer to it. Therefore, at least from one user, 
that is the road name. So not having it in OSM is an omission.

>> [...]
>> If you hope that relicensing will reduce the amount of OS Opendata, I
>> think you might be disappointed. Many significant contributors have
>> signed the CTs on the assumption that LWG will find a way to allow
>> continued OS Opendata importing. [1][2]
>>      
> Yet there does, rather curiously, appear to be a correlation between
> importers/tracers and ODbL refuseniks/not-yet-confirmedniks.
Is that anecdotal or can you provide a reference to evidence? The top OS 
Opendata importer (brianboru) and probably the biggest NPE tracer (Steve 
Chilton) have agreed to the CTs. This seems to be a common thread of 
your arguments - you make wild claims (like OSM's countryside mapping is 
"outstanding", tracing is always a disaster), but you little or nothing 
to back your conclusions.

Regards,

TimSC