# Weighted Density



## memph (Dec 11, 2010)

Usually, when people compare the densities of different urban areas, they look at the total land area/total population. Doing this results in the density value for Los Angeles being greater than that of NYC. While this is ok for trying to figure out how expansive an urban area is relative to its population, it's not good for giving a feel of what kind of densities the typical resident of an urban area lives at, which affects how suitable an urban area is to high usage of public transit, walkability, etc. 

Here's how weighted density differs from overall density.

You have a place with 10 people living on 10 acres and another 100 people living on 1 other acre for a total of 110 people on 11 acres. 

The overall density is 10 people per acre. (110/11)

The weighted density reflects that 91% of the population lives at a density 100 people per acre and only 9% at 1 person per acre. The weighted density would be 91 people per acre. (0.09*1+0.91*100)

Austin Contrarian looked at the weighted densities of the largest US urban areas, calculated at a census tract level:
http://www.austincontrarian.com/austincontrarian/2008/03/weighted-densit.html

I calculated the weighted densities of several major Canadian urban areas to see how they'd compare.

Some of the above cities, as a result of their small size, are already going to be quite strongly affected by "fringe census tracts" which include pockets of relatively high density suburban development closer to the city but also large amounts of rural land that bring down the density of the census tract. The smaller the urban area, the less accurate the weighted density.

Here are the weighted densities so far (combined with US urban areas from Austin Contrarian) in people per square mile with the urban area population in brackets:

1. New York: 33,029 (17,799,861)
2. San Francisco-Oakland: 15,032 (2,995,769)
3. *Toronto: 14,853* (5,178,773)
4. *Montreal: 14,128* (3,299,497)
5. Los Angeles: 12,557 (11,789,487)
6. *Vancouver: 12,093* (2,189,688)
7. Honolulu: 11,989 (718,182)
8. Chicago: 10,270 (8,307,904)
9. San Jose: 8,766 (1,538,312)
10. Philadelphia: 8,457 (5,149,079)
11. *Ottawa: 7,747* (1,022,490)
12. *Hamilton: 7,743* (693,793)
13. Boston: 7,711 (4,032,484)
14. *Winnipeg: 7,643* (673,856)
15. *Calgary: 7,228* (1,101,023)
16. San Diego: 7,186 (2,674,436)
17. Baltimore: 6,952 (2,076,354)
18. Washington: 6,835 (3,933,920)
19. Miami: 6,810 (4,919,036)
20. *Quebec City: 6,759* (704,772)
21. Las Vegas: 6,662 (1,314,357)
22. *Edmonton: 6,457* (878,827)
23. *Victoria: 6,145* (303,963)
24. *London, ON: 6,106* (376,032)
25. *Regina: 5,992* (193,100)
26. *Kitchener: 5,872* (462,262)
27. Milwaukee: 5,830 (1,308,913)
28. *Oshawa: 5,820* (297,808)
29. *Saskatoon: 5,686* (222,079)
30. *Halifax: 5,472* (328,962)
31. *St Catharines-Thorold: 5,375* (150,967)
32. Phoenix: 5,238 (2,907,049)
33. Denver: 5,231 (1,984,887)
34. *Windsor: 5,193 * (283,940)
35. Sacramento: 5,043 (1,393,498)
36. Cleveland: 5,033 (1,786,647)
37. Detroit: 4,955 (3,903,377)
38. Seattle: 4,747 (2,712,205)
39. Dallas-Fort Worth: 4,641 (4,145,659)
40. Riverside-San Bernardino: 4,514 (1,506,816)
41. Houston: 4,514 (3,822,509)
42. Portland: 4,383 (1,583,138)
43. Minneapolis-St Paul: 4,196 (2,388,593)
44. San Antonio: 4,090 (1,327,554)
45. Austin: 3,904 (901,920)
46. Virginia Beach: 3,883 (1,394,439)
47. Pittsburgh: 3,698 (1,753,136)
48. St Louis: 3,566 (2,077,662)
49. Tampa: 3,558 (2,062,339)
50. Cincinnati: 3,274 (1,503,262)
51. Kansas City: 3,041 (1,361,744)
52. Atlanta: 2,362 (3,499,840)

The US numbers are from the 2000 census and the Canadian ones from the 2006 census.

So, any surprises? 

I've also got the weighted densities of the Canadian core cities and suburbs for the urban areas I've done (including the former Metropolitan Toronto cities like North York, East York, etc) and can make density distribution graphs if anyone's interested.

Here are cities from other parts of the world I've attempted, but they often had much larger units, which causes them to seem less dense than they really are:

Barcelona (incomplete): 57,915 (3,840,842)
Zaragoza: 41,103 (681,097)
Madrid: 37,610 (5,144,053)
Paris (incomplete): 30,894 (9,508,637 not including some suburbs I haven't added yet)
Budapest (city proper): 14,810 (1,729,031)
Hamburg (city proper): 13,768
Sydney: 6,860 (4,091,720)


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## isaidso (Mar 21, 2007)

These results make more sense than the usual density numbers that get bandied about. Would you mind adding Halifax and Victoria?


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## the spliff fairy (Oct 21, 2002)

cool what would be the weighted densities of European and Asian cities?


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## poshbakerloo (Jan 16, 2007)

I'm still a bit confused as to what is the difference between density and weighted density?

It would be interesting to see some UK cities in comparison like Manchester, Birmingham, Sheffield, Leeds, Liverpool and London. UK cities tend to sprawl a lot more than other European cities...


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## memph (Dec 11, 2010)

isaidso said:


> These results make more sense than the usual density numbers that get bandied about. Would you mind adding Halifax and Victoria?


Yeah I can do those, the amount of time it takes for me to calculate these basically depends on the population of the urban area, and those are pretty small.



the spliff fairy said:


> cool what would be the weighted densities of European and Asian cities?


These take a while to calculate, at least for Canadian cities. Basically, you need to get the populations and densities (or land areas) of all the census tracts in an urban area. Ideally, the urban area should be determined in the same way as the American ones, which might complicate things a little. I'm not familiar with European/Asian census data, so I'm not sure how long it would take. For the American cities it's much easier than the Canadian ones. I'm also only fluent in English and French, and sort of Hungarian, so I might need a little help there too.



poshbakerloo said:


> I'm still a bit confused as to what is the difference between density and weighted density?


I tried explaining the difference in the OP using an example, but basically the usual density measurements look at the density of the average piece of land in a certain area, while the weighted density looks at the density the average person in a certain area lives at.


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## memph (Dec 11, 2010)

Added Halifax. While Halifax has decent core density for a city of its size, the peninsula had 60,628 people at a weighted density of 11,062ppsm, the suburbs are quite low density compared to other Canadian cities and there's quite a bit of very low density areas like Hammond Plains Road and Beaver Bank that are barely dense enough to be included.

Also, while you're waiting for Victoria, here's a graph of the density distribution of the 3 largest Canadian urban areas (inhabitants/km2):








It shows Montreal has a lot of people living at density of 9-18,000/km2 and has a greater range of densities than Vancouver and Toronto. Toronto has a smaller range of densities at which a significant portion of it's residents live, making it much more like Los Angeles than Philadelphia or NYC and "peaks" at a slightly higher density than Montreal. Vancouver is basically like a slightly less dense version of Toronto, but with slightly higher proportion of it's population living at densities of about 20,000/km2 (downtown Vancouver)... although that might change by the 2011 census.


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## memph (Dec 11, 2010)

Added Victoria, Winnipeg, which has a very similar density distribution to Ottawa and Edmonton, which is very similar to Calgary.

Here's the density distribution for the next 3 densest Canadian cities (at least of the ones I've done):








Quebec City has more variation in density with more low density and a little bit more high density than Ottawa and Hamilton, but much less moderate density (2500-5000/km2).

I'm planning on doing Winnipeg next. Anyone want to guess what its weighted density will be?


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## alyers (Nov 30, 2011)

the usual density numbers that get bandied about.


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## DiggerD21 (Apr 22, 2004)

I like that idea, however it might get difficult to calculate that weighted density as precise as possible for many cities as the administrative district boundaries within the cities might not be suitable enough for that exercise. Take for example Hamburg. The statistics office keeps population data for each of the 104 districts. However, the area size of each district is very different. And some large districts have a rather densely populated core area while the remaining area is sparsely populated. The following image illustrates the problem: The thick lines are the borough borders. Each borough is subdivided into districts (thin lines). The grey layer beneath is illustrating built up area.









http://upload.wikimedia.org/wikiped...isions.svg/608px-Hamburg_Subdivisions.svg.png

The density is 2,373.7/km2 (6,147.8/sq mi). Now finding out the weighted density would be interesting. I was doing a similar exercise once by simply substracting the districts which were largely of rural character from the total land area and population. I ended up having a density of the (somewhat) urban area of around 3000/km2 (about 7,800/sq mi).


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## memph (Dec 11, 2010)

I suspect the weighted density for Hamburg would be a fair bit higher, probably around 12-18,000ppsm just looking at the administrative districts, and maybe as much as 50% higher still if broken up into pieces more comparable in size to US and Canada census tract. US/Canada census tracts both have about 5000 people, although in Canada at least, it's quite common to have census tracts anywhere as small as 1000 people and as large as 10000 people, with a few that are even up to around 20,000. The ones around 20,000 people are usually in areas that grew very fast and would be broken up into smaller census tracts by the next census.

If Hamburg has 1.8million people and 104 districts, that's 17,000 people in the average district, so about 3 times greater than census tracts... It would be a little problematic around the edge of the urban area if it includes rural areas, but a lot of Canadian census tracts around the fringe include a small subdivision and then a large swath of countryside... so it might not be too bad... How about districts that are fully urbanized? If you divide them into 3 similarly populated pieces, would there still be significant variation? In the case of Toronto for instance, adjacent census tracts in the suburb of Brampton might have densities that are within 10-20% of each other, so if Brampton was divided into sections of 17,000 people instead of 5,000, it wouldn't make a too big difference, but in Toronto's inner suburbs and parts of the inner city where there are highrises, you might have one census tract with a density 3 times greater than the one next to it.

Do you know if other European countries might divide their cities into smaller sections (about 5000 people) when keeping statistics? I would be interested in finding the weighted density of Zaragoza, Spain, I suspect its weighted density might be higher than that of Paris or New York. 

Also, I added Kitchener (tri-cities) and Winnipeg.


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## DiggerD21 (Apr 22, 2004)

The closest to these canadian census tracts are probably electoral districts which are set up before municipal elections (which are in Hamburg at the same time state eleczions, as Hamburg is one of Germany's 16 federal states). AFAIk these should have about the same amount of inhabitants. But I doubt that they have/publish data about the area size of these electoral districts, so that it is a hassle to determine their population density.

Population density can vary greatly between adjacent administrative districts in Hamburg, even in continious urban areas. The city center for example has a high building density, but a low population density. The districts around the Alster lake in the city center are full with villas, but around them are often more dense districts.

The most dense of the 104 administrative districts is Hoheluft-Ost with 18,086/km2 (ca. 47,000/sq mi), but it just has 0.7km2 (ca. 1.8 sq mi) land area. The least dense one is Waltershof with 5 people on 9 km2 (ca. 23 sq mi), which is due to being a district completely used by the seaport. The largest district in terms of Land area is Wilhelmsburg with 35.3km2 (ca. 91sq mi) which represents almost 5% of Hamburg's total area, and 1424/km2 (ca. 3700/sq mi).

I doubt that the weighted density for Hamburg would be 12-18.000 ppsm or even higher. That would be 4600 - 7000 inhabintants/km2. Hamburg is a very suburban cityscape for its size. It's area is almost as big as NYC, but just has less than 1/4 of NYC's population.

As for Zaragoza, I can imagine that it is much denser than at least Hamburg. If it would be denser than NY, I don't know. But I would say that spanish cities are very dense in comparison to most other european cities.

I don't know how other cities are keeping their statistics. Even within Germany there is no one way to keep statistics about districts, which is due to different status, size and capabilities of each city. The most comprenhensive data in this regard might be available about Hamburg, Berlin and Bremen, as these are city states and their statistics are being conducted at a higher administrative level.


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## memph (Dec 11, 2010)

DiggerD21 said:


> The closest to these canadian census tracts are probably electoral districts which are set up before municipal elections (which are in Hamburg at the same time state eleczions, as Hamburg is one of Germany's 16 federal states). AFAIk these should have about the same amount of inhabitants. But I doubt that they have/publish data about the area size of these electoral districts, so that it is a hassle to determine their population density.
> 
> Population density can vary greatly between adjacent administrative districts in Hamburg, even in continious urban areas. The city center for example has a high building density, but a low population density. The districts around the Alster lake in the city center are full with villas, but around them are often more dense districts.
> 
> ...


Yes but NYC's weighted density is quite a bit higher than that of its urban area. I would expect the weighted density of NYC proper to be between 50,000 and 80,000ppsm... so if Hamburg is 1/4 as dense, it might still have a weighted density of around 15,000ppsm.

15,000ppsm is not that dense. The weighted density for Mississauga is 11,663ppsm. Admittedly, Mississauga has a very high rises, but it still has plenty of single family home neighbourhoods with densities in the 10,000-15,000 range... or even higher if there are some attached homes. Brampton is even more suburban, and it still has a weighted density of 9809ppsm.

This area of Markham has a density of more than 20,000ppsm, despite being just detached single family homes with deep lots, wide streets and a few parks:
http://maps.google.com/maps?q=Markh...=bFRdiNlLGyWL_Ggv-xcCWg&cbp=12,336.05,,0,-3.4

Do you know where I can get density data for Hamburg's districts?

The reason I expect Zaragoza to be so dense is that about 27% of its population lives at densities of 50,000ppsm or more (averaging at 79,300ppsm) while New York's urban area has about 24% of its population living at densities of 50,000ppsm or more (averaging at 82,937ppsm). So relative to its size, its densest 25% are about as dense as New York's... except that looking at google maps, the remaining 75% of Zaragoza looks to be very dense too, while for New York, much of the remaining 75% is much lower density. 

My estimates are based off these two sources:
http://www.austincontrarian.com/austincontrarian/2011/04/a-cool-graph-of-city-densities.html
http://www.demographia.com/db-hyperdense.htm


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## wc eend (Sep 16, 2002)

Cool! I've been looking for a tool like this since a long time, since I'm very interested in density but inhabitants per surface is such a crappy indicator. Even cooler would be to know the weighted density of entire countries.


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## DiggerD21 (Apr 22, 2004)

memph said:


> Do you know where I can get density data for Hamburg's districts?


English Wikipedia, and in case a quarter doesn't have its own wikipage in english, German Wikipedia.


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## memph (Dec 11, 2010)

DiggerD21 said:


> English Wikipedia, and in case a quarter doesn't have its own wikipage in english, German Wikipedia.


OK I just finished Hamburg, its density weighted by quarter is 13,768ppsm. I would still expect the weighted density to rise a fair bit if you broke down large quarters into sections of about 5000 people... even if you included areas outside Hamburg proper that are part of the urban area (while excluding areas within the city proper not part of the urban area). It's hard to say whether the density would rise to above that of San Francisco-Oakland though. Hamburg's density distribution appears to be quite similar to that of Montreal.

I added Saskatoon and Windsor too.


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## DiggerD21 (Apr 22, 2004)

Thanks for the effort.  Yes, the municipal borders of Hamburg don't reflect the size of the urban area. But that is a general issue with european cities. Take for example Paris.

As Hamburg is one of the least dense big cities in Germany, or even in Europe by the traditional method, it would be interesting how the city compares with the weighted density.


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## memph (Dec 11, 2010)

OK I did a few European cities

Zaragoza urban area: 41,103ppsm (681,097 people)
For Zaragoza I used districts, since I couldn't find data on its wards (barrios) which are smaller. The average district had 47,600 people, so much bigger than a census tracts and even quite a bit bigger than Hamburg wards. The densest district was Delicias, with a population of 114,000 and density of 90,000ppsm. Using census tract sized sections, I would expect the weighted density to be at least 50,000ppsm, possibly even 60,000ppsm. 

Madrid City proper: 57,089 ppsm (3,273,006 people)
For the city proper, I was able to find information on the wards (barrios), which had 25,600 people each. The densest ward was Embajadores with a density of 125,874ppsm and population of 50,196.

Madrid Urban Area: 37,610 ppsm (5,144,053 people)
The Madrid urban area is the city plus a bunch of suburbs which have 110,000 people on average. The suburbs are actually fairly dense, but include often a lot of undeveloped land, which lowers the density. If census tract sized sections were used, I would expect the urban to have a weighted density of about 50,000 ppsm.

Paris City Proper: 72,917 ppsm (population 2,125,841)
For Paris, I used districts (quartiers) of which there are 80, so about 26,600 people each on average. The densest district was Folie-Mericourt at 117,733 ppsm with 33,002 people. I'm still working on the urban area... but Paris' urban area doesn't seem as dense as Zaragoza or Madrid's. It might end up having a weighted density lower than New York's, although its communes are also (in addition to districts) larger than a typical census tract, so when you take that into consideration, I would expect it to be of similar density to New York or a little denser.

By the way, if anyone knows where I can get data on districts/wards or ideally even smaller units for their city, let me know.

I would expect Spanish and maybe Greek urban areas to have the highest weighted densities in the developed world (unless you count Hong Kong or maybe Singapore), with Japanese and Italian ones being quite dense as well, maybe comparable to Paris and New York. I'm less sure about Eastern European cities, some have lots of "commie-blocks", but because of the greenspace surrounding them, and the fact that they're often not *that* tall (around 10-15 stories), I would expect them to be less dense than Spanish urban areas, but some might compare to NYC or Paris.


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## wc eend (Sep 16, 2002)

^^ I think you are right.


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## the spliff fairy (Oct 21, 2002)

South Korea is the worlds densest country in terms of urban areas alone, it should have a very high count.

Half the population lives here: 24.5 million in contiguous Seoul-Incheon, worlds second biggest city, and almost entirely highrise:


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## gincan (Feb 1, 2006)

memph said:


> Do you know if other European countries might divide their cities into smaller sections (about 5000 people) when keeping statistics? I would be interested in finding the weighted density of Zaragoza, Spain, I suspect its weighted density might be higher than that of Paris or New York.


You could do Barcelona if you like, the city has ridiculous density in its central parts and its adjacent cities (Badalona, Santa Coloma and L'Hospitalet, I'll dig up some numbers for you to look at. For Barcelona alone ca 90% of its 1,6 million inhabitants live on half the municipality, IE 1,5 million in 50 sq kilometres. Santa Coloma according to is own municipal data has an urban density of ca 32,000 per sq kilometre, Badalona ca 25,000 and L'Hospitalet ca 20,000.

Here are the densest neighbourhoods in people/sq miles, these are only neighbourhoods with at least 50,000 people per square kilometre. Including all with at least 40,000 per sq kilometre you'll end up with a list more that twice as long.

Population - density/sq mile - neighbourhood (city)

8,032 - 214,452 - Can Mariner (Santa Coloma) 
29,416 - 201,585 - La Florida (L'Hospitalet) 
14,927 - 170,681 - Santa Rosa (Santa Coloma) 
17,669 - 160,062 - El Fondo (Santa Coloma) 
26,928 - 159,738 - La Torrassa (L'Hospitalet) 
24,507 - 154,584 - Sants-Bada (Barcelona) 
15,379 - 147,524 - Sant Mori (Badalona) 
9,959 - 145,817 - El Llatí (Santa Coloma) 
34,838 - 138,922 - el Camp d'en Grassot (Barcelona)
13,141 - 136,140 - Sant Joan (Badalona) 
38,917 - 135,897 - el Camp de l'Arpa del Clot (Barcelona) 
12,418 - 135,477 - Verdun (Barcelona) 
21,851 - 133,695 - Navas (Barcelona) 
52,890 - 130,336 - La Sagrada familia (Barcelona)

320.872 people living in neighbourhoods with at least 50,000 inh/sq kilometre
these numbers are from 2009 and 2008

If you want to do Barcelona you can check out bcn.cat and there go to http://www.bcn.cat/estadistica/angles/dades/index.htm and there go to figures by neighbourhoods, there are 73 of them.


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## memph (Dec 11, 2010)

the spliff fairy said:


> South Korea is the worlds densest country in terms of urban areas alone, it should have a very high count.
> 
> Half the population lives here: 24.5 million in contiguous Seoul-Incheon, worlds second biggest city, and almost entirely highrise:


I could try... but do you know where I can get data on the population of individual districts, neighbourhoods, census tracts or whatever South Korea uses? Ideally they should be areas that average out as close as 5000 people as possible. 

It would take a really long time to do unless I can get tables with the population and density (or land area) though, since the urban area is so huge.


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## memph (Dec 11, 2010)

gincan said:


> You could do Barcelona if you like, the city has ridiculous density in its central parts and its adjacent cities (Badalona, Santa Coloma and L'Hospitalet, I'll dig up some numbers for you to look at. For Barcelona alone ca 90% of its 1,6 million inhabitants live on half the municipality, IE 1,5 million in 50 sq kilometres. Santa Coloma according to is own municipal data has an urban density of ca 32,000 per sq kilometre, Badalona ca 25,000 and L'Hospitalet ca 20,000.
> 
> Here are the densest neighbourhoods in people/sq miles, these are only neighbourhoods with at least 50,000 people per square kilometre. Including all with at least 40,000 per sq kilometre you'll end up with a list more that twice as long.
> 
> ...


Thanks!

I guess there isn't any data at a lower level than neighbourhoods/Barrios?

Anyways, weighted by population at the neighbourhood level, Barcelona (city proper) has a density of 80,362ppsm. That's definitely very dense, I wonder if Barcelona achieves higher densities than Paris because the courtyards are smaller and maybe the streets are narrower? Or smaller units/larger households/less commercial uses?

Now it's just a question of how the suburbs will impact the density of the urban area. I've started with L'Hospitalet de Llobregat since the Spanish Wikipedia has articles with the density of most neighbourhoods. However there were a few neighbourhoods where they didn't list the population and density: Collblanc (District II) and Can Serra (District V) so does that mean there is no-one living in those districts or was the data just missing? For Gran Via Sud (District III) and the Economic District (VII), the population and density was left blank, so I assume no-one lives in those two?


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## gincan (Feb 1, 2006)

memph said:


> Thanks!
> 
> I guess there isn't any data at a lower level than neighbourhoods/Barrios?


Not that I know of, at least not in any public data.



memph said:


> Anyways, weighted by population at the neighbourhood level, Barcelona (city proper) has a density of 80,362ppsm. That's definitely very dense, I wonder if Barcelona achieves higher densities than Paris because the courtyards are smaller and maybe the streets are narrower? Or smaller units/larger households/less commercial uses?


Smaller units, and higher dwelling density per hectare, some streets in Barcelona (Barceloneta, Raval and some other low income areas) reaches an absolute density above 2000 people per hectare despite being in an otherwise low average density area. Eixample for example has an average density of close to 70,000 people per sq kilometre when roads are not counted.



memph said:


> Now it's just a question of how the suburbs will impact the density of the urban area. I've started with L'Hospitalet de Llobregat since the Spanish Wikipedia has articles with the density of most neighbourhoods. However there were a few neighbourhoods where they didn't list the population and density: Collblanc (District II) and Can Serra (District V) so does that mean there is no-one living in those districts or was the data just missing? For Gran Via Sud (District III) and the Economic District (VII), the population and density was left blank, so I assume no-one lives in those two?


Here you can find statistics for:

L'Hospitalet
http://www.l-h.cat/anuarisEstadistics_2.aspx?id=2|

Santa Coloma
http://www.grame.net/es/principal/la-ciudad/datos-estadisticos.html

For Badalona there is no public data online other than population data for every barri, but that data is not useful without the size of the barris.

I do have data for the districts though

District - size - average density per square kilometre
1 2,1 km2 12066 
2 0,87 km2 32850 
3 11,7 km2 2690
4 0,44 km2 40302
5 0,93 km2 48717
6 0,84 km2 25566
7 1,36 km2 17765
8 0,80 km2 20414

Anyway, both Santa Coloma and Badalona are denser than Barcelona when one only count the urban area. In the case of Badalona for example, of the 220K inhabitants, 113K of them live in the south corner of the municipality on just 2,47 km2 (11% of the municipality) at an average density of almost 46K per Km2. This stand in stark contrast to the average density for the whole municipality which is below 10K.


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## memph (Dec 11, 2010)

gincan said:


> Not that I know of, at least not in any public data.
> 
> 
> 
> ...


So Barcelona has a weighted density of 80,362ppsm, L'Hospital de Llobregat 112,774ppsm and Santa Coloma 117,229ppsm.

As for Badalona, I found a PDF with the populations of the districts (which I need)... but they seem to have 9 districts. Do you know what the density of the 9th one is?

Do all of the municipalities of Cataluyna have their own websites with this information? There's quite a few other municipalities that could be considered part of the urban area, at least using the American definition...


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## gincan (Feb 1, 2006)

memph said:


> So Barcelona has a weighted density of 80,362ppsm, L'Hospital de Llobregat 112,774ppsm and Santa Coloma 117,229ppsm.
> 
> As for Badalona, I found a PDF with the populations of the districts (which I need)... but they seem to have 9 districts. Do you know what the density of the 9th one is?


Here are all the barris for Badalona

Barri - population - size
Artigues 5054 0,09 km2
Bonavista 1310 0,38 km2
Bufalà 13916 0,63 km2
Can Claris 2744 0,12 km2
Canyadó 2763 0,19 km2
Canyet 542 5,63 km2
Casagemes 7634 0,56 km2
Centre 8221 0,58 km2
Coll y Pujol 2931 0,25 km2
Congrés 3691 0,10 km2
Dalt de la Vila 4107 0,20
El Remei 1058 0,30 km2
Gorg 5669 0,62 km2
La Mora 449 0,56 km2
la Pau 4614 inv 0,10 km2
Les Guixeres 0 1,25 km2
la Salut 20024 0,44 km2
Lloreda 2759 0,14 km2
Manresà 318 0,34 km2
Mas Ram 597 0,46 km2
Montogalà 7275 2,20 km2
Morera 6582 0,50 km2
Nova Lloreda 11750 0,24 km2
Pomar 4835 0,60 km2
Pomar de dalt 68 1,74 km2
Progrés 10917 0,59 km2
Puigfred 8561 0,27 km2
Raval 8994 0,25 km2
Sant Antoni 15861 0,40 km2
Sant Mori 15311 0,27 km2
Sant Joan 12718 0,25 km2
Sant Roc 13980 0,34 km2
Sant Crist 10453 0,24 km2
Sistrells 4813 0,38 km2



memph said:


> Do all of the municipalities of Cataluyna have their own websites with this information? There's quite a few other municipalities that could be considered part of the urban area, at least using the American definition...


No, the problem is that only some of the municipalities publish their statistical data online. In the extended Barcelona urban area neither Cornella, Sant Just Desvern or Sant Joan Despí offer any data online. Sant Feliu de Llobregat does offer statistical data and El Prat de Llobregat only population data but no corresponding geographical data.

For municipalities further out it is almost impossible to get it right, they usually has a very dens core 10-20K/km2 (along the railway corridors) and are surrounded by farmlands or mountains sparsely urbanized. Some municipalities like for example Corbera de Llobregat, consist of dossens of small urban areas of single family houses much more in the style of your typical north american suburban sprawl.

For an example of the typical (mountain/urban/agricultural) municipalty in the second urban ring around Barcelona you can look at the data for Sant Boi.

Land use
http://observatori.santboi.cat/files/2558-182-document/Superfícies per ús.pdf

Population by district, there are 5 of them in pdf form.
http://observatori.santboi.cat/DetallPublicacio/_shHHNiF7Ow1D5LgAfpJ047YziwcMHMBJBnWEPLiLO44


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## memph (Dec 11, 2010)

Cool, so the weighted density for Badalona at a neighbourhood level is 84,176ppsm. For Sant Feliu at the neighbourhood level it's 55,757ppsm and for Sant Boi at the district level it's 17,635ppsm. I've also done Terrassa (in Valles Occidentale) at the neighbourhood level, its weighted density at a neighbourhood level is 45,507ppsm. I think Terrassa would be considered part of the urban area of Barcelona using the United States' methodology.

Here are the other cities I think should be included (in addition, there are a few others I'm less sure should be included) ranked in order of population:

Sabadell (Valles Occidental): 207,721
_Cornella de Llobregat (Baix Llobregat): 87,243_
Sant Sugat del Valles (Valles Occidental): 83,337
Rubi (Valles Occidental): 73,979
Viladecans (Baix Llobregat): 64,737
_El Prat de Llobregat (Baix Llobregat): 63,499_
Cerdanyola del Valles (Valles Occidental): 58,247
Esplugues de Llobregat (Baix Llobregat): 46,687
Gava (Baix Llobregat): 46,250
Ripollet (Valles Occidental): 37,348
Montcada i Reixac (Valles Occidental): 34,232
Sant Adria de Besos (Barcelones): 34,157
_Sant Joan Despi (Baix Llobregat): 32,406_
Barbera del Valles (Valles Occidental): 32,033
Premia de Mar (Maresme): 28,310
Sant Vicenc des Horts (Baix Llobregat): 28,137
Sant Andreu de la Barca (Baix Llobregat): 27,094
Santa Perpetua de Mogoda (Valles Occidental): 25,331
Molins de Rei (Baix Llobregat): 24,572
El Masnou (Maresme): 22,523
Vilassar de Mar (Maresme): 19,840
Sant Quirze del Valles (Valles Occidental): 19,051
_Sant Just Desvern (Baix Llobregat): 16,253_
Corbera de Llobregat (Baix Llobregat): 14,064
Castellbisbal (Valles Occidental): 12,267
Palleja (Baix Llobregat): 11,272
Montgat (Maresme): 10,739
Premia de Dalt (Maresme): 10,168
Alella (Maresme): 9,570
Vilassar de Dalt (Maresme): 8,794
Cervello (Baix Llobregat): 8,651
Tiana (Maresme): 7,973
Santa Coloma de Cervello (Baix Llobregat): 7,931
Viladecavalls (Valles Occidental): 7,376
Cabrils (Maresme): 7,196
Teia (Maresme): 6,162
Torelles de Llobregat (Baix Llobregat): 5,661
Cabrera de Mar (Maresme): 4,528
El Papiol (Baix Llobregat): 3,941 
La Palma de Cervello (Baix Llobregat): 3,019
Ullastell (Valles Occidental): 1,904

The underlined ones are the suburbs which you said don't have the data we need.

I haven't split these into districts or neighbourhoods in my excel table yet. The ones with the biggest populations would have the highest priority for being split into district or neighbourhoods (if we can find info). For now, all those suburbs are weighted at the city level. Combine these with the Barcelona and the suburbs that have been split into smaller units, and the weighted density for the whole area is 57,915ppsm with a population of 3.84million.


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## gincan (Feb 1, 2006)

memph said:


> Cool, so the weighted density for Badalona at a neighbourhood level is 84,176ppsm. For Sant Feliu at the neighbourhood level it's 55,757ppsm and *for Sant Boi at the district level it's 17,635ppsm*. I've also done Terrassa (in Valles Occidentale) at the neighbourhood level, its weighted density at a neighbourhood level is 45,507ppsm. I think Terrassa would be considered part of the urban area of Barcelona using the United States' methodology.


This is the problem I tried to describe about the municipalities outside of Barcelona urban area. Basically unless you can get hold of very detailed data it makes little sense to use it, I'll take Sant Boi as an example below.

The Municipality is made up of the following areas

Agricultural 39,1%
Comercial 3,8%
Public spaces (squares, parks and sports facilities) 7,4%
Forrests 15,6%
Industrial 10,2%
Roads 3,7 percent
Railroads and busslanes 1,5%
Residential 16%
Other 2,8%

Now, in Sant Boi with the exeption of the odd farmhouse all residential buildings are bunched up in a single area so the 16% space used for residential is a good indicator of how dense the urban area is, basically 1,3 sq miles used for all housing in the municipality. 

When one add the roads, public spaces, office and comercial buildings, railroads and urban forests, at the very most you dubble the area, so if we use say 2,5 sq miles for the populated area of the municipality you'll have 82680/2,5 sq miles. 

That gives ca 33.000 and this is still only the average without taking into consideration the different densities within this area ranging from single family houses to 10 story apartment blocks with hundreds of units in each. Without having any data to back it up with, I'd still say Sant Boi is denser than Sant Feliu, at least that is the sensation when you se both from street level.


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## memph (Dec 11, 2010)

gincan said:


> This is the problem I tried to describe about the municipalities outside of Barcelona urban area. Basically unless you can get hold of very detailed data it makes little sense to use it, I'll take Sant Boi as an example below.
> 
> The Municipality is made up of the following areas
> 
> ...


Well Canadian census tracts often included commercial, industrial, large parks and urban forests and airports. Usually the boundaries weren't drawn so that the non-residential land was in one census tract and the residential was in another. Most Canadian cities also had large census tracts at the edge of the urban area with populations of 10,000-20,000 but only 10% of the land in the census tract was urbanized and 90% was rural (forests and agricultural). Suburban Toronto also has a very significant stock of high rises, and some of the high rise clusters are large enough to have their own census tract, but they're often still separated into multiple census tracts so that you have several census tracts that are part high rise, part detached single family homes.

Anyways, we'll see how many of the suburbs have the same problem as Sant Boi and whether it's worse than for the Canadian/American or even other European cities. I agree that it's a problem, but if other cities have the same problem, it might still work for an apples to apples comparison. Until then, the weighted density for the cities in Barcelones is 85,686ppsm, which I think reflects the situation on the ground relatively well.


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## Vaud (Sep 16, 2011)

This is a very interesting topic, thanks memph, I do think your method reflects fairly well real population densities in different cities. 

I have made the same exercise for a Swiss city, Lausanne. You can access the information on population and territory for extremely small urban departments of the city in an excel table in here: Lausanne (the authorities keep a lot of control on who's living where and finally I see it's worth at least for something :lol

I have calculated the weighted density on the smaller divisions and the result is 33,548ppsm

That's for the core city. The metropolitan area is defined as this: Agglomération Lausannoise 

I have found the information on the population but unfortunately not the surface. I have only been able to get the surface on the towns as a whole. For Renens, for example, 92% of its 296ha surface is urban area, for Prilly that's 80% and 219ha, Pully 54% and 585ha, Ecublens 56% and 571ha, Bussigny-près-Lausanne http://www.scris.vd.ch/Data_Dir/ElementsDir/3291/3/F/5624_BussignyLausanne_RFP2000.pdf45% and 482ha, and Lutry 33% and 846ha. 

These together with Lausanne cover 80% of all population in the urban area. 

Using all that data I get 41,311,3ppsm for Lausanne+all these other metropolitan towns but the method is not the best one.


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## memph (Dec 11, 2010)

So you got higher densities for the suburbs than in Lausanne itself?

I got a weighted density of 27144ppsm for Lausanne + the other towns you mentioned.


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## SydneyCity (Nov 14, 2010)

Does anyone have "weighted densities" for Australian cities?


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## spxy2 (Sep 26, 2011)

Trying to find some population density figure for Roath in Cardiff, UK.

One website states "In fact, by virtue of the student population, Roath and Cathays is the most densely populated city region in Western Europe."

Now I know this cant be true, but it is very dense for a UK city area...


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## the spliff fairy (Oct 21, 2002)

Athens would be quite something too.

http://www.skyscrapercity.com/showpost.php?p=86743643&postcount=18


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## Vaud (Sep 16, 2011)

memph said:


> So you got higher densities for the suburbs than in Lausanne itself?
> 
> I got a weighted density of 27144ppsm for Lausanne + the other towns you mentioned.


Well it is possible, suburbs are more likely to have more high-rise apartments than Lausanne, so their densities can be higher, it didn't surprise me. How did you reach that number? I multiplied the suburbs area times its urbanized area, but even when not doing it I reach a different number from yours (38,954), what am I doing wrong? I divided by 259 the ha figure, then computed density per sqm then multiplied for each borough the density times the % of population over the total that lives in there and just added all these numbers.


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## memph (Dec 11, 2010)

Vaud said:


> Well it is possible, suburbs are more likely to have more high-rise apartments than Lausanne, so their densities can be higher, it didn't surprise me. How did you reach that number? I multiplied the suburbs area times its urbanized area, but even when not doing it I reach a different number from yours (38,954), what am I doing wrong? I divided by 259 the ha figure, then computed density per sqm then multiplied for each borough the density times the % of population over the total that lives in there and just added all these numbers.


I did 2.59*population/(total land (km2)*percent urbanized)

I got
Renens: 17,506ppsm (pop 18,406, 2.7232 urbanized km2)
Prilly: 16,195ppsm (pop 10,955, 1.752 urbanized km2)
Pully: 13,146ppsm (pop 16,034, 3.159 urbanized km2)
Ecublens: 8,284ppsm (pop 10,227, 3.1976 urbanized km2)
Bussigny-près-Lausanne: 8,953ppsm (pop 7,498, 2.169 urbanized km2)
Lutry: 7,672ppsm (pop 8,270, 2.7918 urbanized km2)

For Lausanne I got 34,621ppsm with a population of 134,753. When you were doing the weighted density by neighbourhoods, did you make sure to exclude the districts from your calculations (they were also in the table)?


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## Vaud (Sep 16, 2011)

^^ yes I did, we both are right in the calculus at least for the suburbs, but your data is different. I just realized the excel for the metropolitan's area population reaches only 2000, so it's not comparable to Lausanne's city 2010. With official december 2010's numbers, the population at the end of the year is:
Bussigny-près-Lausanne 8.065
Ecublens 11.102
Prilly 11.430
Renens 19.609
Lutry 9.305
Pully 17.121

I also think I did a mistake as I didn't properly divide by the sum of all the population the aforementioned cities. With that the weighted population density would be 26,386ppsm for these cities+lausanne and 33,548ppsm for Lausanne alone. At least that's close, I don't know where the difference comes from but nevermind, it's already a good indicator on what's the density of a relatively large Swiss city. 

I will try further on to do the same for Geneva which is much bigger and feels densier. I'd like to do it for Zurich too, but I am afraid I won't be able to find the data in german.


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## Vaud (Sep 16, 2011)

So I calculated the weighted densities for the canton of Geneva (44 towns+16 division of the city of Geneva), plus the towns of Nyon and Gland (in canton Vaud) as the largest cities in district Nyon which is also part of the metropolitan area of Geneva, plus the cities of Annemasse and Saint-Julien-en-Genevois and le pays de Gex all in France. There still some population left but that accounts for over 80% the largest metropolitan area unit.

The weighted density for all that (602,657 hab) is 17,852ppsm and for the 16 divisions of the city of Geneva alone is 41,039ppsm.

I have also made a map for the city with population densities, the scale is on square kilometres, red for over 30,000ppskm, orange over 20,000, yellow over 15,000, green over 10,000, dark blue over 5,000 and light blue over 1,000:










The densiest red coloured part has 34,501 ppskm or 89,356 ppsqm.


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## memph (Dec 11, 2010)

The 2011 Canadian census came out a couple weeks ago, so I recalculated the weighted densities. Substantial increases in weighted density occured in Toronto (5.9%), Vancouver (6.8%) and Calgary (11.4%). I'm not sure how to explain the large increase for Calgary, maybe because the new subdivisions are getting denser, or maybe because more of the 2006 census tracts included large amounts of rural land that brought down the density. Calgary's core neighbourhoods did get denser as well though, so that would be responsible for part of the increase. 

Most other Canadian urban areas saw small increases or little change to weighted density. Windsor's weighted density decreased the most by 3.7%, which is not too surprising since the population of the urban area dropped by 1.2% too.

Toronto passed Montreal.
Vancouver passed Honolulu.
Ottawa passed Boston and Hamilton.
Calgary passed Quebec City, Las Vegas, San Diego, Washington, Baltimore and Miami.
And some smaller changes among the smaller urban areas.

This is still compared to the 2000 numbers for US urban areas. The 2010 census numbers for US urban areas are supposed to be released around late 2012/early 2013.


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## memph (Dec 11, 2010)

Toronto and Vancouver saw not just growth in downtown, but also a lot of growth in suburban nodes and new single family homes being built at higher densities (infill and greenfield).

Are there any US urban areas people think might increase their weighted densities? I expect San Francisco, Los Angeles and Miami will, and maybe New York and Phoenix.


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## Nolke (Oct 25, 2003)

memph said:


> Thanks!
> 
> I guess there isn't any data at a lower level than neighbourhoods/Barrios?


_Secciones censales_ (like in this map), span over one or several blocks if it's an urban area. You can get pretty much every info you want for that level of detail. 

But there're two problems: first, there're thousands of these sections (almost 1500 for the municipality of Barcelona alone); and second, it's very difficult to get spatial data about them... you cannot know their surface. The only way to get that information easily is working with a GIS while having a coverage with these sections (which is not easy to obtain for free), so you can make a join operation between the two tables through the statistical code field (both have them). 

If you are interested, you can get the census data from here (change to English if you want, the language option is at the upper left corner) and choose _inframunicipal_, then select the municipalities (by selecting the province first) and then the sections. As for the coverages, here you have some for free, but I must warn you that the sections organization changes quite fastly so it might be possible that the codes from the census don't match those in the coverages at times:

Barcelona municipality: http://www.aesig.es/infosig/cartografia/bcn/cartografia_bcn_e.htm

Andalusia community: http://www.juntadeandalucia.es/sist..._l_id=43357&folderId=43285&name=DLFE-1906.zip

I think Madrid was also available somewhere...


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## mhays (Sep 12, 2002)

memph said:


> Toronto and Vancouver saw not just growth in downtown, but also a lot of growth in suburban nodes and new single family homes being built at higher densities (infill and greenfield).
> 
> Are there any US urban areas people think might increase their weighted densities? I expect San Francisco, Los Angeles and Miami will, and maybe New York and Phoenix.


Several cities have been seeing a large volume of infill (some today, many in the last boom) coupled with less outward sprawl. I'd add Seattle and Portland to your list...even while some sprawl still happens, and the volume of infill isn't on the epic Miami in 2006 scale.


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## memph (Dec 11, 2010)

mhays said:


> Several cities have been seeing a large volume of infill (some today, many in the last boom) coupled with less outward sprawl. I'd add Seattle and Portland to your list...even while some sprawl still happens, and the volume of infill isn't on the epic Miami in 2006 scale.


I guess that's possible. Seattle and Portland's urban areas have a weighted density of 4500ppsm, which is quite low, so it wouldn't take too much for their densities to increase.

There are a few things to keep in mind when trying to evaluate whether the weighted density will increase.

Regarding sprawl: how dense is the sprawl? Is it much less dense than the average, equally dense or more dense?

Regarding infill, if the effect on Census Tracts is

Very low density becomes low density: may decrease the weighted density since there it involves an increase in the population living at densities below the previous average
Low density becomes medium density: will likely increase the weighted density slightly, but not too much. Many cities might have a lot of apartments being built downtown, but there is still a lot of parking lots, lowrises, offices, etc in the census tracts that contain those new apartments, so this might only represent an increase in density for those CTs from low to medium
Medium becomes very high density: will substantially increase the weighted density, although even in Toronto's condo neighbourhoods, it's mostly been medium to high or high to very high.
High becomes medium density: will substantially decrease the weighted density, especially if on a large scale. This can occur if there is decreasing household sizes in the inner city neighbourhoods but no construction of new units (or rehabilitation of abandonned ones).

When I say low/high density, I mean relative to the average

In the case of Toronto, you had new sprawl at densities roughly comparable to current densities to the average; intensification in areas that were moderate to high density (mostly condo towers); decreasing densities in a few inner city hoods (mostly early 20th century), but other inner city hoods made up for that with small scale intensification; some very low density brownfields became low density since they were only partially redeveloped; many low-mid density suburban areas held their population as teardowns brought larger families and occasional small scale intensification.


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## mhays (Sep 12, 2002)

Seattle and Portland were originally dominated by bungalows (pre-war), and later (50s-70s especially) by larger lot suburbia. Both are interspersed by a lot of steep hillsides, ravines, wetlands, and other undevelopable land. The result is low baseline density. 

But Oregon created a fairly ironclad growth management system. Washington created a system, though a looser one particularly outside King County. This is greatly reducing outward sprawl, particularly in Oregon. It's also helping encourage infill everywhere. 

Both are seeing large amounts of infill, particularly Seattle at the moment. The result is apartment districts amidst the houses. It's a veeery slow process to push up even weighted densities, but they should be going up. As for average densities, even with growth management there's still outward expansion, particularly in Seattle, and depending on your methods, the outward growth might still outstrip the infill.


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## Suburbanist (Dec 25, 2009)

I see a major conceptual problem with this "weighed density" thing: the area unit of measurement.

How do you define which are the units whose average weighed (on population) density will me considered?

There are multiple approaches possible, and they'd yield very different results. An extreme case would be considering each measurement unit as each individual building, which would make the so-called "weighed density" skyrocket.

If defining what constitute a "city area" for purposes of calculating population density is already a very contentious subject, making population comparisons between countries difficult, specifying an uniform criteria to measure weighed density is close to impossible, therefore rendering the utility of the concept as a tool for comparison almost moot.

Let me put other way: how would I calculate my density? Do I consider only the houses on the same block? Only other houses within an officially recognized neighborhood/subdivision name?


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## memph (Dec 11, 2010)

Suburbanist said:


> I see a major conceptual problem with this "weighed density" thing: the area unit of measurement.
> 
> How do you define which are the units whose average weighed (on population) density will me considered?
> 
> ...


Definitely, the smaller the unit of measurement, the higher the weighted density. For the United States and Canada, the unit used was census tracts, which contain on average about 5000 people in all cities of both countries. This does mean that dense census tracts are going to have smaller land areas. I guess you could argue that it would be better to use units of the same land area instead of units of the same population, but to me weighted/perceived density means the density of the average neighbourhood, and in high density areas, neighbourhoods are often considered to be smaller in terms of land area.

In the case of European and Australian cities, they don't have census tracts, so that's why I didn't put them in the same list as the Canadian and American cities.


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## memph (Dec 11, 2010)

mhays said:


> Several cities have been seeing a large volume of infill (some today, many in the last boom) coupled with less outward sprawl. I'd add Seattle and Portland to your list...even while some sprawl still happens, and the volume of infill isn't on the epic Miami in 2006 scale.


So I just ran the numbers for 2010 for SF-Oakland and Los Angeles' urban areas. Note that these two don't include the whole urbanized area but the area defined by the US census bureau which is affected by commute patterns. Also note that my 2010 numbers are based off the 2000 urban area definition, not the expected new 2010 urban area changes that would merge a lot of the urban areas.

San Francisco's urban area includes San Francisco, Alameda County (not counting Livermore area), San Mateo County, Contra Costa from El Cerrito to Rodeo and Marin County.

Los Angeles' urban area includes most of LA county except Santa Clarita, Lancaster-Palmdale and part of Malibu, most of Orange County except Lake Forest/Mission-Viejo and San Bernardino County from Fontana Westward.

San Francisco
2000: 15,032 ppsm (2,995,769)
2010: 14,740 ppsm (3,306,927)

Los Angeles
2000: 12,557 ppsm (11,789,487)
2010: 12,543 ppsm (12,238,786)

Maybe there are rather few US urban areas that got denser? I'm still expecting Miami's urban area to get denser though.


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## Suburbanist (Dec 25, 2009)

^^ In many cities, any "densification" via more residential units in a given area is outdone by the reduction on the average number of people per household.


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## Northsider (Jan 16, 2006)

Today I leaned Las Vegas, Miami, and _Denver_ have denser urban areas than Chicago. Hmm.

Good discussion though, I like it.


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## mhays (Sep 12, 2002)

You can certainly densify core areas and scattered spots, while a lot of static areas see smaller household sizes, like suburban housing that hits the 20-year mark and the kids move out. 

Those SF and LA numbers show population growth but less density. So they expanded the boundaries. The numbers would be higher otherwise.


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## memph (Dec 11, 2010)

mhays said:


> You can certainly densify core areas and scattered spots, while a lot of static areas see smaller household sizes, like suburban housing that hits the 20-year mark and the kids move out.
> 
> Those SF and LA numbers show population growth but less density. So they expanded the boundaries. The numbers would be higher otherwise.


Maybe the urban area expanded a little, but I'm pretty sure there was no merging of previously separate urban areas. Also, it's possible for population to increase and weighted density to decrease even if the boundaries are totally static through intensification of very low density areas and decreasing household sizes in dense areas (or at least no change to these dense areas).

Example: 
The core has a population of 100,000 in 10 square miles and the outlying areas have a population of 100,000 in 100 square miles. The weighted density is 0.5*10,000 ppsm + 0.5*1,000 ppsm = 5500 ppsm.

Not the outlying/low density areas get denser with 300,000 people in 100 square miles, this means that while the low density areas are denser, they also make up a larger part of the overall population. The weighted density is 0.25*10,000 ppsm + 0.75*3,000 ppsm = 4,750 ppsm.



Northsider said:


> Today I leaned Las Vegas, Miami, and _Denver_ have denser urban areas than Chicago. Hmm.
> 
> Good discussion though, I like it.


Chicago has quite low density suburbs compared to many sunbelt cities, so the gross/overall/standard density of its urban area is lower. However, it's basically a situation where a small portion of the population lives on a large portion of the land, with the average Chicagoan living at relatively high densities. Weighted density takes this into account, so Chicago's weighted density is actually higher than that of those 3 other urban areas.


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## memph (Dec 11, 2010)

Phoenix
2000: 5,238 ppsm (2,907,049)
2010: 4,716 ppsm (3,833,048)

Miami
2000: 6,810 ppsm (4,919,036)
2010: 7,445 ppsm (5,517,315)

So it seems Miami has gotten significantly denser. I didn't expect that kind of decrease for Phoenix, but it kind of makes sense. If you look at Phoenix, the sprawl is actually not that dense, but not only that, it's often scattered across the desert, with many gaps in development, but the gaps are not large enough to be considered separate from the urban area. Meanwhile, I'm not sure if Miami had such gaps in the past, but I guess because it's hemmed in by the Everglades, it doesn't have many now.


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## memph (Dec 11, 2010)

Chicago
2000: 10,270 ppsm (8,307,904)
2010: 9,125 ppsm (8,814,602)
2010 including Kenosha: 9,047 ppsm (8,944,424)

Houston
2000: 4,514 ppsm (3,822,509)
2010: 4,589 ppsm (5,153,230)
2010 including Conroe: 4,554 ppsm (5,212,160)

Houston's urban area merged with Conroe, TX and Chicago's merged with Kenosha, WI so I have the numbers before and after. There were probably some smaller mergers as well that are included in the first 2010 values.


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## memph (Dec 11, 2010)

While I'm slowly chugging away at NYC, Washington and Boston, here's a graph comparing the density distribution of San Francisco-Oakland and Toronto, which are have very similar weighted densities (Toronto just edges out SF).

The first graph show the percent of people living at certain densities and the second shows the total population at those densities. The official definition for San Francisco's urban area doesn't include San Jose, so Toronto's UA population is larger. I think for the 2010 census the urban areas will include all urbanized land in a CSA instead of the 2000 definition of all contiguous urbanized land in a MSA (more or less), so in order to be able to compare to the 2000 values, I followed the 2000 rules for 2010.


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## memph (Dec 11, 2010)

I did two other urban areas, both of which saw their weighted densities increase. In the case of Boston, the urban area didn't really expand outwards. There was greenfield development, but it was mostly filling in gaps of undeveloped land. Washington had fairly substantial TODs built, so it's not too surprising it's weighted density increased.

Washington
2000: 6,835 ppsm (3,933,920)
2010: 7,405 ppsm (4,652,979)

Boston
2000: 7,711 ppsm (4,032,484)
2010: 8,159 ppsm (4,458,009)


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## gabrielbabb (Aug 11, 2006)

In Mexico City 34,533 ppsm or 13,333 ppskm, for 20 million in about 1500km2 or 539mi2


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## memph (Dec 11, 2010)

gabrielbabb said:


> In Mexico City 34,533 ppsm or 13,333 ppskm, for 20 million in about 1500km2 or 539mi2


Nice!

Did you calculate that yourself? What was the approximate population of the average district/neighbourhood/census tract used?


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## memph (Dec 11, 2010)

Citypopulation.de has data at a level equivalent to census tracts for Randstad.

http://www.citypopulation.de/php/netherlands-randstadnoord.php

I calculated the weighted density for Amsterdam, it seems they use 2012 population estimates.

Population: 790,090
Weighted Density: 31,053 / sq mi or 11,990 / km2

I also tried to delineate an urban area using contiguous tracts of >500ppsm (US Census Bureau definition of urban) for my blog and got:

Population: 1,702,825
Weighted Density: 21,990 ppsm (8490 /km2)
Population above 50,000 ppsm: 162,330
Population above 20,000 ppsm: 669,760 
Population above 10,000 ppsm: 1,330,010

I'm not sure what the wiki stats for the 1.1 million Amsterdam urban area are based on, but I'm guessing it doesn't include Haarlem and the towns North and South of it which I included.
http://swontariourbanist.blogspot.ca/2015/01/amsterdam-area-weighted-density.html

Depending on the exact boundaries, it would probably work out to around 25,500 ppsm for the 1.1 million area.


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## 009 (Nov 28, 2007)

some numbers for Hong Kong would be interesting


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## memph (Dec 11, 2010)

009 said:


> some numbers for Hong Kong would be interesting


I agree, but I haven't been able to find any data at a level lower than the district level. Districts have around 300,000 people each so it's not going to give particularly meaningful values, especially for Hong Kong where a lot of the districts have small areas that are developed and large areas that aren't.


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## memph (Dec 11, 2010)

Neat comparison of weighted density in European vs Australian cities. Their numbers match up to the ones I got for the few European cities I attempted to calculate the weighted densities of.
http://chartingtransport.com/2015/1...s-of-australian-and-european-cities/#comments

The densest European cities (pop 1m+) are Barcelona followed by Madrid, Valencia, Athens and Paris.

New York City would still rank near the top, probably somewhere a bit after Paris.

The next densest American/Canadian cities would be about comparable to the least dense European cities, mostly smaller cities in northern Europe (UK, Ireland, Sweden, Finland, Germany).

Australian cities are not especially dense, denser than the Southeast and many Midwestern and Great Lakes cities but no denser than Northeastern, Western/SW and South Florida. I'm pretty sure they're less "spiky" than NE cities too, but still have decently vibrant downtowns and transit use.


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## Bardo12345 (Jan 11, 2016)

Concuerdo con gincan


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## memph (Dec 11, 2010)

2016 Canadian Census update - starting to go through these, although it will probably take a while to do every city.

Calgary Urban Area (using US Census Bureau Criteria)

2016
Population: 1,244,345
Weighted Density: 7,572 ppsm

That's up from 2011
Population: 1,101,023
Weighted Density: 7,228 ppsm

A reasonable increase in density but not as significant as 2006-2011.

2006: 6488 ppsm
2011: 7228 ppsm
2016: 7572 ppsm

That's despite a significant increase in infill and inner city growth.


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## The Polwoman (Feb 21, 2016)

For the Netherlands, Rotterdam would be a pretty interesting city to research: the high densities in the city itself, with some lower-density neighbourhoods, but much more the enormous port and within some villages makes Rotterdam likely even more complex than Hamburg. It's relatively small, maybe take the urban area into account, but I'm interested.


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