Wednesday 12 October 2016

Crowdsourced City Boundaries

One Friday afternoon a couple of weeks ago, while putting off something more important, I felt the sudden need to see if I could successfully crowdsource some city boundaries. I'd been doing this kind of thing with housing market boundaries for a few years but I thought it would be interesting to see how many shapes I could get people to draw, so here are the results - for fun more than anything else but I think they are also pretty interesting. If you want to download the raw data, you can go back to the original page and click the Download Data button in the bottom right. I've kept it very simple. First of all, the maps are overlaid on a black and white map and the brighter shading shows where more shapes overlap. For places in the UK, I've also overlaid local authority boundaries to give a sense of how the drawn shapes compare to administrative units. The code for this tool was written by Nick Martinelli (thanks a lot) - I just modified it slightly. You should be able to see the detail in the maps when you click on them.

Yes, this is definitely Birmingham

100% Edinburgh - that's it settled

Someone thinks Glasgow is pretty big!

This seems pretty sensible to me

Let's claim a bit of sea while we're at it

This seems big, but is probably not far from the truth

London's functional reach really does go far beyond the boundary

Yes, 'Manchester' is still the classic 'underbounded' city

Now for some US cities - I've just added the ones which had the most shapes drawn for them, starging with Chicago. I see someone has very carefully added in what looks to be an almost exact representation of the actualy city boundary - impressive!

Well done for the detailed city boundary drawing

Los Angeles County (pop c.10m) comes out a bit here

People seem to have mostly drawn the boundary of the 5 boroughs

For New York (and across the US), Jen Nelles helpfully pointed out to me on Twitter that the term 'city' has a different meaning and perhaps I should have used 'urban' or 'metro', which is a good point. When I did this I was only really thinking about the UK but then I got drawn cities coming in from all over the world, so keep that in mind when interpreting these.

Some detailed shapes were drawn for Philadelphia

I find Seattle particularly interesting - nice commutersheds here

Some evidence of people drawing the administrative boundaries here

And now some other cities from different parts of the world - I would have added more but some cities (e.g. Auckland) only had a couple of shapes drawn.

I've left a couple of nearby places in here too

There weren't that many shapes here but it's still quite interesting

Lots of blocky shapes in Tornoto, which I found interesting

And finally, three more images, one of which includes one of the rude shapes drawn by several scoundrels who defaced my map! 

Someone drew a giant knob over Wales - very naughty

A full size GB/IRE version 

I particularly like the way Munich has been drawn here.

And that's all I have to say about this little adventure in crowdsourced procrastination. Thanks to everyone who drew a shape or shared the link online. I've found it very interesting. Feel free to use any of this if you find it of interest. Now time for me to get back to what I should have been doing in the first place.

Notes: I'm did this as a little mapping experiment after seeing Colin Ross do it for Western Sydney (which was inspired by earlier Bostonography work). Earlier work by people such as Kevin Lynch and Patrick Abercrombie is also relevant here. Edinburgh City Council also ran a project like this in 2014 called 'Natural Neighbourhoods' and there are countless other examples across the world. A deliberately prettified/extreme pink example of some earlier stuff I did with this (using housing market data) can be seen on the Rightmove blog. That example involved millions of shapes, whereas we're only just into the thousands for this blog. If you want to see some of my academic work on this, in relation to housing market geographies, take a look at this paper (open access) - an example image is shown below. 

This was generated using data from Rightmove's 'Draw-a-Search' tool