[Talk-GB] OpenKent, OSM coverage estimation

[Richard Fairhurst]

TimSC wrote:
> I think you miss my point. The datasets contain more than just their
> postal address. If the licenses are compatible, we can mash up the data.

You don't need to put stuff into OSM to make it mashable-uppable. Most
competent licences will have a Collective Work/Database provision to
enable this.

>> And you should do that anyway.
> This implies I don't already, which is a false. (Otherwise, why are you
> telling me I should?)

Oh, cool. Sorry, I thought you were still using Yahoo imagery to trace
places you'd never been. Glad you've stopped. :)

> [...]
> Any what if the government dataset is open and stomps on OSM's attempt?

OS OpenData is easily the best free geodata available in the UK and I've
just used it (in preference to OSM) to make a lovely paper map, but it
hasn't killed OSM yet. :)

> (Don't bother saying "improve OSM" because that IS the approach we use
> and still the government set is better, in some cases.) Duplicating
> other open data sets seems a waste of time - as you seem to imply by
> resurveying stuff already available elsewhere.

In a few cases, manually importing data can indeed be a useful tool. The
high-resolution rivers and streams in VectorMap District are quite useful
_if_ you know the stream is indeed there, which obviously VMD doesn't tell
you. It's not really any better than using a combination of aerial imagery
and your own knowledge, but it can be useful, yes.

But this is pretty much only true where the data is impractical to survey
yourself. The canonical example is: if you import a town's roads, you get
a town's roads. If you survey a town's roads, you get a town's roads,
footpaths, cycle routes, pubs, etc. etc. I'm sure there's been an example
where an import has been significant in the success of OSM in the UK but
I'm struggling to think of one. Maybe someone else can help?

> I am not advocating we
> only import data either. A hybrid approach - import AND crowd source -
> is better. If you want crowd sourced surveying only, I suggest you start
> another project.

Fortunately, I _like_ the licence that 23135 people have said they'll move
their data to, and only 387 have said they won't (that's 98.4% vs 1.6%).
So I'm not planning to be one of the people moving to another project. :)

cheers
Richard