[Talk-GB] too many universities in Cambridge

Dan S danstowell+osm at gmail.com
Fri May 22 12:21:57 UTC 2015


Right, OK thanks. So let me try and answer without raising any
sub-controversies - that's why I was reluctant to answer "what would
you show for cambridge"!

If there was a single mortar-board for every geographically
self-contained UoC "site" on the map - that seems rather reasonable.
The minimalist way to achieve that would be for those sites to have
amenity=university tag, and for none of the buildings within them to
have that tag. (The humanitarian map would then look good...) I
personally would find that still a little bit curious but here I'm not
proposing to impose my ideal relation-tastic solution, since you've
raised some objections to that kind of thing.

For university buildings that are standalone, not part of a larger
"site" - well I guess if I had to design a map I wouldn't put any
mortar-board for them, though I might decide to give them a
mortar-board at the highest zoom level. (This might be achieved via
building=university perhaps. Though the question is about the
rendering not the tagging.)

Is this a meaningful answer to your rendering question? I hope so.

Best
Dan


2015-05-22 13:03 GMT+01:00 David Earl <david at frankieandshadow.com>:
> Sorry, that wasn't intended to be provocative, it was a serious question.
> Irrespective of how it is tagged, how should one show a spread out
> institution on a map? If you do ARU with two mortar boards or some such
> should Cambridge be 10, one for each site, 41 including the colleges, or
> what? One could argue that it's the mapping you cited that's inadequate
> because it should collapse them into one when they are sufficiently close
> together to not be distinct (like ios does for photo locations on a map for
> example*), and that when zoomed in you *do* want them to be shown
> separately. In any case neither the current scheme nor a relation scheme
> preclude that, they are currently group-able by operator (which is a much
> more sustainable way of relating them IMO than relations).
>
> I asked about the building=university rendering because it would be a shame
> to lose the university buildings as distinct on the main map, and I have no
> control over fixing that. No doubt someone would catch up with it
> eventually.
>
> I would have to go back to the code to see what the exact implications of
> removing the amenity tags are, it's three years since I wrote it. I am
> almost certain that changing building=yes to building=university is
> harmless, but if I then have to rely on it, we have to be careful that
> university libraries aren't tagged building=library for example as the
> information gets lost.
>
> David
>
> * in similar vein one of the developments that's been requested for the
> university map is that when you get a search hit where the result blobs are
> overlapping they should be merged into one. This is very hard to do, so it
> will cost a lot.
>
>
> On Fri, 22 May 2015 at 12:40 Dan S <danstowell+osm at gmail.com> wrote:
>>
>> 2015-05-22 12:33 GMT+01:00 David Earl <david at frankieandshadow.com>:
>> >> to render a map using a UK-wide rendering scheme that indicates
>> >> each university prominently
>> >
>> > What *would* you show for Cambridge (or other spread out ones) for this?
>> > Where actually *is* the University of Cambridge? What would you show
>> > that
>> > the current tagging doesn't already achieve?
>>
>> It doesn't matter what I would do. The UoC tagging is inconsistent
>> with the tagging for other universities, in a way that means no-one
>> can currently design a UK-wide map render that can handle universities
>> properly.
>>
>> I understand that you don't like this erupting under your feet, but
>> I'm afraid that's what happens in wiki-like systems. Please, please be
>> happy that I'm a considerate map editor who tries to discuss rather
>> than just to edit. We have absolutely no guarantees that a map editor
>> who loves consistency but doesn't love communication will not break
>> your schema at any moment!
>>
>> I'd be really grateful if you could comment on my suggestion about
>> modifying the building tags.
>>
>> Best
>> Dan
>>
>>
>> > On Fri, 22 May 2015 at 12:30 David Earl <david at frankieandshadow.com>
>> > wrote:
>> >>
>> >> Does the main OSM rendering understand building=university?
>> >>
>> >>
>> >> On Fri, 22 May 2015 at 12:27 Dan S <danstowell+osm at gmail.com> wrote:
>> >>>
>> >>> Hi David,
>> >>>
>> >>> Thanks for the detailed info. My main concern is in terms of the
>> >>> consequences for other data consumers. If someone tries to use OSM
>> >>> data for anything - such as:
>> >>>  (a) to plot the density of universities per county
>> >>>  (b) to render a map using a UK-wide rendering scheme that indicates
>> >>> each university prominently
>> >>> - the results will be utterly wrong. So we do need some consistency,
>> >>> at least at the country-wide level. (I'm pragmatic enough not to aim
>> >>> for global consistency ;)
>> >>>
>> >>> So I'm not offended, but I do care that our data is good for everyone.
>> >>> I suggest that we should make a change but I will not rush anything!
>> >>>
>> >>> I don't know what this "camp" is that didn't like building=university.
>> >>> Was it an OSM camp (eg a discussion on the tagging email list)? Either
>> >>> way, building=university is now used quite a lot worldwide
>> >>> http://taginfo.openstreetmap.org/tags/building=university#map - I
>> >>> think it's pretty uncontroversial as a building tag.
>> >>>
>> >>> So the question, I guess, is what "jobs" amenity=university is doing
>> >>> in your scheme. Is it being used as a selector for extracting data? Is
>> >>> it being used as a selector for rendering-rules? You've got your
>> >>> operator=* tagging which looks good for selecting a data extract.
>> >>>
>> >>> If we made a two-step change such that all "building=yes,
>> >>> amenity=university, operator=.*University of Cambridge.*" were first
>> >>> modified to building=university, and then after a few months to remove
>> >>> the amenity=university from buildings and leave it on
>> >>> sites/universities/whatever-we-agree-it-should-be-on - would that work
>> >>> for you? My quick overpass check suggests that would address about 800
>> >>> of the 1200 objects.
>> >>>
>> >>> Best
>> >>> Dan
>> >>>
>> >>>
>> >>> 2015-05-22 11:54 GMT+01:00 David Earl <david at frankieandshadow.com>:
>> >>> > 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
>> >>> >> >
>> >>> >> > _______________________________________________
>> >>> >> > Talk-GB mailing list
>> >>> >> > Talk-GB at openstreetmap.org
>> >>> >> > https://lists.openstreetmap.org/listinfo/talk-gb
>> >>> >>
>> >>> >> _______________________________________________
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