A place to share and discuss data visualizations. #dataviz
source: https://www.reddit.com/r/dataisbeautiful/comments/15uz539/city_street_network_orientation/
From the post:
Urban spatial order: street network orientation, configuration, and entropy
By: Geoff Boeing
This study examines street network orientation, configuration, and entropy in 100 cities around the world using OpenStreetMap data and OSMnx.
See full paper: https://appliednetsci.springeropen.com/articles/10.1007/s41109-019-0189-1
I assume it's unintentional that this is so low resolution that the city names are barely readable
edit: the original image, before it was rehosted with the shit compressed out of it, is much higher res and is actually readable.
I thought this was useless until I spotted my current city of Detroit, it matches well enough
Completely awesome content, thanks. I was hoping that some older cities were more random, and I was not disappointed.
This is a pretty cool visualization, thanks for sharing!
Also I'm glad I've never lived in a grid city, feels off somehow.
I feel constantly lost in non-grid cities. The Grid makes navigation so easy.
I’ve lived in Boston and Detroit. Detroit is so much better to navigate in. I think if Boston included Cambridge, Somerville, Brookline and the other outskirts that are really greater Boston, it would be even more circular. It’sa mess getting around there.
I've never felt anywhere near lost in a good non-grid city, particularly in the Netherlands and close-by of course.
The reverse is true for non grid dwellers.
Growing up in Florida I thought I was good at telling the Cardinal directions because it was easy to align with the roads
Now that I live in Boston I can't navigate anywhere
Does this mean all roads lead to Charlotte and not Rome as I was lead to believe?
This means roads in Charlotte are fucked with no discernable patterns or thought behind how they are laid out.
In other word the roads from Charlotte go every which way. Then, all of those every which way roads lead to Charlotte. So that means if every possible way leads to every possible place then every possible road must lead to Charlotte. Conclusion: joke’s dead.
the earlier in this table, the more boringer the cookie-cutter city.
But I may be biased, seeing as I live in and love Stockholm...
How is supposed to be interpreted? For example Helsinki is right on the coast and sure as shit hasn't as many roads going south in to the drink compared to other directions
Every road going south is also a road going north. Note all of them have rotational symmetry
It'd be interesting to know how one way streets are counted
Just read the study? They modelled street networks as undirected graphs, one-way streets are treated like all other streets, as their directionality isn't considered.
Street networks are typically modeled as graphs where nodes represent intersections and dead-ends, and edges represent the street segments that link them (Barthelemy and Flammini 2008; Cardillo et al. 2006; Lin and Ban 2013; Marshall et al. 2018; Porta et al. 2006). These edges are spatially embedded and have both a length and a compass bearing (Barthelemy 2011). The present study models urban street networks as undirected nonplanar multigraphs with possible self-loops. While directed graphs most-faithfully represent constraints on flows (such as vehicular traffic on a one-way street), undirected graphs better model urban form by corresponding 1:1 with street segments (i.e., the linear sides of city blocks). While many street networks are approximately planar (having relatively few overpasses or underpasses), nonplanar graphs provide more accurate models by accommodating those bridges and tunnels that do often exist (Boeing 2018c; Eppstein and Goodrich 2008).
Even if they were counted accurately, usually there is another one way road nearby and which is going the other direction. So I doubt it would have a meaningful impact in the visualization.
One way streets exist!
It's about the orientation of the roads, does the road align cleanly with the compass points or does it skew diagonal? So a clean N/S orientation results in a clean N/S line. When you look closely you'll see the results are mirrored across the axis as a result.
chicago has a great lake to the east so. i dunno.
Yeah, but the measurement is over total length of the roads, not the center of downtown. Every road runs the same distance in each direction, whether or not it's a one way road.
It's histograms, according to the paper:
Fig. 5 Polar histograms from Fig. 4, resorted by descending φ from most to least grid-like (equivalent to least to greatest entropy)
Fig. 4 Polar histograms of 100 world cities’ street orientations, sorted alphabetically corresponding with Table 1
(A histogram shows how much there is of each kind, so here it's how much road there is per direction.)
Is there an advantage to having a city's grid be perfectly oriented along NSEW? I get that if a city has a coast or waterfront, you'd want to align the grid with that, but would it mess anything up if a city's grid were rotated like 15 degrees clockwise?
There's a concept called street canyons that deals with the region's prevailing winds and sunlight. Might end up with your very own Manhattenhenge.
In America, it makes it line up with existing lots. Remember that the homestead act gave a lot of people 40 acres, and those lots were oriented properly. A lot of American cities were built around those lots.
Honestly why would the rotation matter at all? Not like the connecting roads are perfectly straight without curves either.
I wish they'd have done a full NYC analysis. Just doing Manhattan has an obvious outcome, but including Brooklyn, Queens, and the Bronx would yield a more interesting result.
Weird selection of cities. Very U.S. centric considering they claim "geographical diversity".
To better understand urban spatial order and city street network entropy, we analyze 100 large cities across North America, South America, Europe, Africa, Asia, and Oceania. Our sampling strategy emulates Louf and Barthelemy’s (2014) to select cities through a balance of high population, regional significance, and some stratification to ensure geographical diversity within regions.
Charlotte is made worse by road names changing frequently. Tyvola, Fairview, Rama, Idelwild are all the same road. At one point you find yourself at the intersection of Queens and Queens when you thought you were on Providence. If you are on the east side of town and want to get to the west side it's faster to go north and do a gravitational assist and slingshot by our way south than it is to just drive east to west.
My city is on there! And it nearly fills in the whole circle. Unsurprising, as we effectively have streets that intersect with themselves. East coat USA is a clusterfuck of city planning.
The only major parts of Seattle that are not NS/EW are downtown and Belltown. Crackheads Denny and Boren each wanted their plots of land to have roads following different parts of the bay. Maynard called them a bunch of dumbasses and used true cardinal directions for roads.
Charlotte over there trying to color the whole circle hahaha
Denver's entire downtown is a 45 degree slant from the rest of the city so the image is questionable...
Neat chart, thx
Johannesburg lmao. The disorganization and urban sprawl there, that also connects Joburg to Pretoria should be a crime against urban planning. The East Rand, Midrand, Wits, all of it. Apartheid spacial planning and our failure to address it has really messed us up.
Most of Denver is like that, but Lower Downtown is on the 45. Not sure how that's accounted for (if at all) in this chart.
Rio is a pinwheel!
As someone who just drove through Oslo Centrum today, yeah, it's indeed accurate. A fucking mess is what it is.
Where's Zurich?
Switzerland, last time I checked.