[Talk-GB] too many universities in Cambridge

David Earl david at frankieandshadow.com
Fri May 22 10:54:59 UTC 2015


Hi Dan,

Yes, Philip's right - I developed and continue to maintain the University
map at http://map.cam.ac.uk (as well as doing all of the original street
pattern mapping for Cambridge back in 2006). The University has put a
considerable investment and negotiated permission for college access into
the map and contributed tens of thousands of pounds of survey data into OSM
- it's not just "some of its maps", it's completely central to the
University map, not just a casual effort.

The "schema" for tags that make the University map work is at
http://wiki.openstreetmap.org/wiki/Cambridge/University_of_Cambridge (I've
just realised I haven't updated that page with a recent, unrelated new bit,
I must do so).

As it happens, I was also thinking about this the other day. The three main
things are that is (a) consistent and (b) doesn't change under our feet and
break the map, (c) it needs a way to distinguish these buildings from
others. It possibly wasn't the best decision to do it like this, though I
still don't think it is a terrible way to do it. Relations would be awful:
they are very hard to maintain accurately, and incidentally they are hard
to work with in consumers because they come at the end of the data so you
have to do multiple passes or keep lots of data in memory, and I think
you'd lose most of the distinctive renderings off the OSM map, though since
that's such an opaque process it's hard to know.

building=university would work, but only if done in a controlled way so
that we don't break the map while it's being done. But do you really want
to spend your days in front of a computer changing all the university tags
in Cambridge though?! I can think of more productive and helpful things to
do. I did consider building=university, but like all things OSM, there was
a camp that only wanted building=yes, and that is what the Map_features
page then decreed (it has more now, but university isn't among them). The
more critical tags from my point of view are the operator ones.

This raises some other points though...

1. What about the sites and the colleges? These are also tagged University,
and there isn't an obvious alternative that won't mean the ordinary OSM
maps don't show them. Fundamentally, is a "part of a university" a
university? I think it's helpful to do it like that. Did you know the
University of Nottingham has a branch in China - would it really be helpful
to link these with relations spanning the world? I think there's cases both
ways.

2. What is a University anyway? Almost no university is in one physical
area. Even campus universities like UEA have outlying premises (in UEA's
case in London too). Do you really not want the campus area to be tagged
university just because it isn't the whole thing? You said Anglia Ruskin
was one of the two universities in Cambridge - no it isn't, it's HALF a
university, the rest is in Chelmsford. I don't think it would do any harm
and would be helpful to group them with relations, if that were
maintainable sustainably, but not at the expense of losing the tags from
the outline itself. And the building thing only extends this further. Is a
University a geographical thing at all? It's an institution, which may have
some buildings but really it's a concept not a physical object - ultimately
everything on the map is just a part, not the whole.

4. Constantly changing tags creates a moving target that is extremely hard
to maintain for data consumers, and is a major off-putting factor in using
OSM, especially if you can't manage the process because things just change
under your feet. For example, there is a thread on talk discussing
completely changing the amenities altogether, without regard for people who
want to use this stuff in the real world. My view is that tags are merely
tokens and too much is read into the words. They are part of the API and
the fact you can change them because you prefer some other structure
doesn't mean you should. The flexibility means we can introduce new things
easily, but constant change is hard to cope with. The costs are borne
elsewhere, and what really does it buy us?

So, I think it's OK the way it is. If it offends you unbearably,
building=university wouldn't be too hard to cope with, but please, please
don't just do it, let me change the University software first, otherwise
the map will be broken on next update (which are frequent) and they will be
very annoyed. As I said, this is effectively part of the API, even though
it may not feel like it, and constitutes a non-upward compatible change. If
you do want to do it, please do it all, not in bits, and bear in mind this
has a direct financial cost to me as a freelancer supporting the University
map, and that the University has been a big benefactor for OSM, even though
they get the rest of the map back in return, so you really don't want to
give them a slap in the face for doing so.

David


On Thu, 21 May 2015 at 23:13 Phillip Barnett <phillip.p.barnett at gmail.com>
wrote:

> I'm a Cambridge mapper, but I'd advise doing nothing until you've spoken
> with David Earl who was contracted by Cambridge University to actually map
> the university - see this link
> http://soc2012.soc.org.uk/node/16.html
> Thanks
>
>
>
> > On 21 May 2015, at 22:39, Dan S <danstowell+osm at gmail.com> wrote:
> >
> > Hi all,
> >
> > I don't relish bringing this up since it's a bit of a tangle, but I
> > noticed Cambridge has a lot more universities than I thought!
> > Apparently 1219, judging from the number of amenity=university tagged
> > objects. In real life I'm aware of two: Cambridge Uni, Anglia Ruskin
> > Uni.
> >
> > I think someone mentioned Cambridge Uni was using OpenStreetMap for
> > some of its maps,* so I'd be nervous about proposing anything radical
> > right now. But is there anyone on this list who is a Cambridge mapper,
> > or connected to the university's use of mapping? It's possible that
> > some team decided to use the tag to mark every college building (etc),
> > when really amenity=university is supposed to mark a university, not a
> > piece of a university.
> >
> > To do it "properly" it might need some neat relations to group these
> > things. (Might be fun for someone who loves relations - various
> > multi-site and hierarchical connections among the buildings scattered
> > across town!) Alternatively there are tags in use such as
> > building=university which might be good drop-in replacements...
> >
> > Best
> > Dan
> >
> >
> > * They use OSM for their basemap: http://map.cam.ac.uk/ - I wonder if
> > they're getting their POI info from it too
> >
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>
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