[HN Gopher] Where is the most densely populated square kilometre...
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Where is the most densely populated square kilometre in the UK?
(2023)
Author : fanf2
Score : 40 points
Date : 2024-07-11 14:42 UTC (2 days ago)
(HTM) web link (www.statsmapsnpix.com)
(TXT) w3m dump (www.statsmapsnpix.com)
| Svip wrote:
| I wonder if it would be possible to find an even more populated
| square km, if one started turning it.
| KeplerBoy wrote:
| You certainly would.
|
| Just think how insanely unlikely it would be for this not to be
| the case.
|
| One could also increase the density by allowing non square
| shapes or squares not fixed on the grid and so on. A more
| general approach would always lead to slightly higher scores.
| jl6 wrote:
| > non square shapes
|
| Perhaps something akin to a Hilbert curve that snakes around
| the whole country encompassing every individual person's
| footprints but otherwise covers almost-zero area.
| KeplerBoy wrote:
| Sure, but thats a trivial solution. Exploring convex shapes
| however could lead to some interesting insights.
| hiddew wrote:
| Yes, a grid system like H3 https://www.uber.com/en-
| NL/blog/h3/ is is closer to a circle in shape. One of the
| reasons for Uber to use H3 is bacause density maps look more
| natural in hexagonal shapes. It would be interesting to see
| the answer for H3 hexes.
| ghghgfdfgh wrote:
| It would have been better if they looked for the densest circle
| with an area of 1 square km. Although a square shaped area has
| its tangible benefits - you "feel" population density more when
| it's on your own street obviously, and since square areas
| provide more information along a few axes (the ones containing
| the corners), you can get an idea of the population density in
| an area by placing a square's corners on the street. A square
| is probably not the best shape for this, though.
| Duanemclemore wrote:
| Before I even clocked on this I knew it would be in Tower
| Hamlets, famous for being the most densely populated council in
| the UK...
|
| I wonder what a quadtree based approach would look like. I
| mean... I'd almost guarantee you're going to wind up in Tower
| Hamlets again. So the question of how much it costs to optimize
| for so little is there. But still, interesting alternative method
| for someone to gnaw on if they wanted.
| fifilura wrote:
| How i would do it:
|
| 1. Create a table with quad tiles of appropriate size/level as
| Parquet. Put it in s3 and map it as a table in AWS Athena
| (Trino)
|
| 2. Put the census data in s3/Athena.
|
| 3. Join using Trino geospatial functions.
| https://trino.io/docs/current/functions/geospatial.html
|
| The result for all quad tiles will be there within a couple of
| minutes.
| jeffbee wrote:
| Why though? We're talking about much less than a million
| geothings here. Any laptop can process this much data at
| interactive speeds.
| fifilura wrote:
| True.
|
| 0. Look at data size.
| fifilura wrote:
| I am trying to understand if the source data also provides the
| population weighted centroid. I guess it has to.no way to
| calculate that.
|
| It would be interesting to know what tools were used for running
| the calculation.
| walthamstow wrote:
| One of the great things about London is that almost all of the 63
| 1km squares they highlight here contain a decent size park or
| other green space
| macintux wrote:
| I'd be curious how many of those spaces were open to the public
| 100 years ago.
|
| J. Draper uploaded a remarkably interesting video recently
| about railings and green space in London.
|
| https://youtu.be/JHvKvOUSor4
| GaggiX wrote:
| Now I wonder what would be the most densely populated square
| kilometer in the world instead. I would imagine something like in
| Hong Kong.
| Duanemclemore wrote:
| I think so - or Singapore. Maybe Mumbai. Once upon a time
| called last year maybe a sqkm of Gaza would sneak in.
| snicky wrote:
| Once I've heard that Mong Kok area was the most densely
| populated neighbourhood in the world.
| HPsquared wrote:
| Kowloon Walled City will forever hold the record, I think.
| Density of 1.9M per square km. (Before it was demolished of
| course)
| arethuza wrote:
| Wasn't that just because it was tiny (0.026 square kilometre)
| and a population of 35,000? I think for a discussion about
| "most densely populated square kilometres" we should actually
| be talking about square kilometres?
| HPsquared wrote:
| Fair enough. That 0.026 sq.km. has more people living in it
| than the most densely populated full sq.km. in the UK
| though, which must count for something. I wonder what the
| population of the square kilometre centred on KWC is/was.
| Georgelemental wrote:
| But the city was much smaller than 1km2, so doesn't qualify
| pydry wrote:
| Probably lalbagh in dhaka. ~170,000 per sq km.
| fragmede wrote:
| No need to guess,
| https://en.wikipedia.org/wiki/List_of_cities_proper_by_popul...
| puts Manilla at the top of the list.
| GaggiX wrote:
| I asked for the most densely populated square kilometer, not
| the most densely populated city. A city's population can be
| spread out evenly or concentrated in a few areas.
| arethuza wrote:
| Interesting to note that for off the reputation of the UK as
| being all densely populated we actually still have more area of
| peat bogs (9.4%) and moors and heathland (7.5%) as urban fabric
| (~5.5%):
|
| https://figshare.com/articles/journal_contribution/A_Land_Co...
|
| Edit: Direct link to a map:
| https://orda.shef.ac.uk/articles/dataset/A_Land_Cover_Atlas_...
|
| Edit2: That pastures are the top use (28.7%) maybe explains why
| "England's green and pleasant land" is justified! (And I say that
| as a Scot!)
| pjs_ wrote:
| https://youtu.be/GELhFB-f8hQ?feature=shared
| fragmede wrote:
| Is Bow E3 - Wiley - Topic what you meant to link?
| pjs_ wrote:
| Absolutely. The single most lyrically gifted grime MC hails
| from the single most densely populated area of the UK -
| Bayesians rejoice
| andrewaylett wrote:
| Random squares is absolutely not cheating -- if you really
| _really_ want a grid, you can always draw one out from the square
| you found.
|
| Indeed, _not_ picking the grid that gives you the best answer
| might be considered cheating :). Unless you 're explicitly going
| for OS grid reference square kilometres, which the first grid may
| have been -- but I see no evidence that the author did so.
|
| And if you want to really not cheat, you probably need to
| consider rotating your grid too.
|
| All that said, I concur that it probably doesn't change the
| result very much. I'm just slightly disappointed that the author
| thought that improving his method to get a more correct answer
| was "cheating".
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