5 ms·

Mapping Traffic Fatalities

71 points by sndean 10y ago

niftich 10y ago
I'm very pleased (from a data insight standpoint) that the map doesn't look like a population heatmap [1]. As a next step, I suggest calculating the actual rate of fatalities in a particular location vs. some naive estimate for that area, based on traffic counts, car utilization, or nearby population. This will highlight places that have a higher-than-expected number of fatalities. Some of these places can already be seen visually. For example, Florida is blotted in red even though the population is concentrated around the coasts and bays and the Orlando area; therefore US 301 and other 'interior' portions are more dangerous than population alone would explain. The Carolinas are similarly covered, well-outside of the Crescent from Raleigh-Durham through the Triad to the Charlotte suburbs. California's Central Valley looks particularly dangerous too, despite most of the traffic sticking to the far western edge with I-5, or the eastern valley floor where the built-up areas are. [1] https://xkcd.com/1138/ https://xkcd.com/1138/
- mtippett 10y ago
  I'd agree that there it would be very nice to correlate with a traffic load graph. For areas like California, where you have pretty much the I-5 or the Highway 1, knowing the fatality per car travelled would be interesting view.
- deleted 10y ago
  [deleted]
- dandermotj 10y ago
  It looks exactly like a population heatmap.
  - dx034 10y ago
    More like a traffic heatmap. California seems to have a lot of red dots on the I5 between LA and SF. Not a lot of people live there.
    - 13of40 10y ago
      I wonder how much "proximity to a good hospital" changes it, as well. If I could zoom in far enough, and traffic can be assumed to be constant, would there be more fatalities on the remote parts of I-5?
- mirimir 10y ago
  This looks interesting: https://i2.wp.com/metrocosm.com/wp-content/uploads/2016/05/usa-traffic-flow-map-large.png https://i2.wp.com/metrocosm.com/wp-content/uploads/2016/05/u...
- nmeofthestate 10y ago
  >Some of these places can already be seen visually. For example, Florida. I think if this is true at all (I'm not sure it is) it's just an artifact of the large blobs used on the traffic fatalities map.
- yaakov34 10y ago
  I agree with one of the posters below: this is a population heatmap, exactly as identified by XKCD (https://xkcd.com/1138/ https://xkcd.com/1138/). Florida, which you mention, is highlighted in red only because this is a small-scale map with poor density representation. Here is Florida with the exact same data, as plotted by me in R with a little more resolution: https://imgur.com/a/WU3JI https://imgur.com/a/WU3JI A population map, in other words. As a very basic demonstration of the capabilities of R, this is OK, but as a visualization, this is 100% useless. You would need something like "percentage of expected fatalities for a given stretch of road, given the type of road" to actually have something interesting. And that takes a lot more work.
tooFastFuckYou 10y ago
What is the underlying platform or language? The post doesn't even give us an introductory statement about the technology involved. Come on, that's ridiculous.
mikhailfranco 10y ago
Already available for the UK, see: http://www.crashmap.co.uk/ http://www.crashmap.co.uk/
coldcode 10y ago
Is it possible to make such a map for homicides? Does the data exist with sufficient location information?
- danso 10y ago
  The FBI Uniform Crime Report and/or NIBRS may be the most comprehensive/granular data there is on homicides nationwide, but I don't think there's incident-level geography: https://www.icpsr.umich.edu/icpsrweb/NACJD/NIBRS/ https://www.icpsr.umich.edu/icpsrweb/NACJD/NIBRS/ Counting homicides, and even determining what exactly is a homicide, is not as clear as one might think: http://contentsmagazine.com/articles/homicide-watch-an-interview/ http://contentsmagazine.com/articles/homicide-watch-an-inter... Not that many agencies post the data themselves. Surprisingly, the NYPD does post it as part of their felonies dataset: https://data.cityofnewyork.us/Public-Safety/NYPD-7-Major-Felony-Incidents/hyij-8hr7/data https://data.cityofnewyork.us/Public-Safety/NYPD-7-Major-Fel...
  - TillE 10y ago
    Good find with the NYPD link. I've seen New York data before that just went precinct by precinct, but this has exact latitude and longitude.
danso 10y ago
have a love-hate relationship with the NHTSA database. On one hand, it covers 40 years of data, and unlike virtually every other long-running dataset in existence, it keeps not only a relatively standardized schema, it publishes a all-in-one user manual that covers every year (and any changes between them); most places publish a new PDF for every year, which means you have to read through each one. Even better is that when they make changes or additions to their methodology, they publish an auxiliary dataset that you can use to retroactively update old datasets. But then for some reason, they throw out all rationality when it comes to naming files and fields. It's as if there was employee who was old-school and was stuck in mindset of naming things under the 8-character all-caps limitation. And then someone else thought, "Fuck this", and went the entirely opposite direction by naming files with long titles and spaces, and the two employees had a passive-aggressive argument that never got resolved over the decades. This makes scraping and collating the data a real pain in the ass. But compiling the data got a lot easier when I realized that wget works on FTP sites. Here's a mirror of the FTP site (around 1.7GB zipped) that I put up on Github (still working on getting everything together in one database): https://github.com/wgetsnaps/ftp.nhtsa.dot.gov--fars https://github.com/wgetsnaps/ftp.nhtsa.dot.gov--fars
laurent123456 10y ago
Isn't it pretty much a US population density map (if it's not, I can't quite see the difference)? If there are differences, it would have been interesting to display the number of accidents in an area as a proportion of the population.
thr0waway1239 10y ago
Would it help to use data like yearly per capita consumption of gasoline by state [1] (as a proxy for miles driven per person) in addition to the existing data? Would that make a difference and shed any more insight? [1] http://www.statemaster.com/graph/ene_gas_con_percap-energy-gasoline-consumption-per-capita http://www.statemaster.com/graph/ene_gas_con_percap-energy-g...
- yaakov34 10y ago
  You can get vehicle miles driven by state directly, and also such data as fatalities per road user and per miles driven: http://www.iihs.org/iihs/topics/t/general-statistics/fatalityfacts/state-by-state-overview http://www.iihs.org/iihs/topics/t/general-statistics/fatalit... However, you won't get much insight from plotting this data geographically: a table (as in that link) is enough. Basically you get exactly what is expected: Daniel Patrick Moynihan's "Law of the Canadian Border" - southern states have more social problems. If you want high-resolution geographical data for purposes such as finding problem roads, that would be a lot more difficult - you need to have a graph of the road network (from e.g. Open Street Map), with traffic data attached to the arcs of the network (I don't know of any public access databases like that, although such data is commercially available for road planning) plus accident locations accurately mapped to the roads. I suspect it wouldn't be a quick project to do.
- fastaguy88 10y ago
  There is something clearly very wrong with this data, since is suggests that California has less than 1/10th the per capita consumption of New York, and uses less fuel on an absolute basis than Connecticut. The dynamic range in fuel consumption differs only 2 fold for the top 46 (of 51) states, but then drops more than 5 fold. Those last 5 numbers must be on a different scale.
Agustus 10y ago
I am struggling with what will be the purpose of this. Any project that I work on with traffic analysis, PD&E, or roadway design includes a crash analysis. The crash analysis includes an analysis of every accident within a five year period, identification of high crash locations and what caused the crash (high speed, inebriation, or a list of other options), and then what strategies can be adopted for the most impact in a benefit/cost analysis. Just looking at heat maps of crashes without inclusion of traffic volumes (one crash per million miles is nothing compared to an area of one crash per thousand miles traveled) becomes meaningless.

71 points by sndean 10y ago

I'm very pleased (from a data insight standpoint) that the map doesn't look like a population heatmap [1]. As a next step, I suggest calculating the actual rate of fatalities in a particular location vs. some naive estimate for that area, based on traffic counts, car utilization, or nearby population. This will highlight places that have a higher-than-expected number of fatalities. Some of these places can already be seen visually. For example, Florida is blotted in red even though the population is concentrated around the coasts and bays and the Orlando area; therefore US 301 and other 'interior' portions are more dangerous than population alone would explain. The Carolinas are similarly covered, well-outside of the Crescent from Raleigh-Durham through the Triad to the Charlotte suburbs. California's Central Valley looks particularly dangerous too, despite most of the traffic sticking to the far western edge with I-5, or the eastern valley floor where the built-up areas are. [1] https://xkcd.com/1138/ https://xkcd.com/1138/

mtippett 10y ago
I'd agree that there it would be very nice to correlate with a traffic load graph. For areas like California, where you have pretty much the I-5 or the Highway 1, knowing the fatality per car travelled would be interesting view.
deleted 10y ago
[deleted]
dandermotj 10y ago
It looks exactly like a population heatmap.
- dx034 10y ago
  More like a traffic heatmap. California seems to have a lot of red dots on the I5 between LA and SF. Not a lot of people live there.
  - 13of40 10y ago
    I wonder how much "proximity to a good hospital" changes it, as well. If I could zoom in far enough, and traffic can be assumed to be constant, would there be more fatalities on the remote parts of I-5?
mirimir 10y ago
This looks interesting: https://i2.wp.com/metrocosm.com/wp-content/uploads/2016/05/usa-traffic-flow-map-large.png https://i2.wp.com/metrocosm.com/wp-content/uploads/2016/05/u...
nmeofthestate 10y ago
>Some of these places can already be seen visually. For example, Florida. I think if this is true at all (I'm not sure it is) it's just an artifact of the large blobs used on the traffic fatalities map.
yaakov34 10y ago
I agree with one of the posters below: this is a population heatmap, exactly as identified by XKCD (https://xkcd.com/1138/ https://xkcd.com/1138/). Florida, which you mention, is highlighted in red only because this is a small-scale map with poor density representation. Here is Florida with the exact same data, as plotted by me in R with a little more resolution: https://imgur.com/a/WU3JI https://imgur.com/a/WU3JI A population map, in other words. As a very basic demonstration of the capabilities of R, this is OK, but as a visualization, this is 100% useless. You would need something like "percentage of expected fatalities for a given stretch of road, given the type of road" to actually have something interesting. And that takes a lot more work.

tooFastFuckYou 10y ago

What is the underlying platform or language? The post doesn't even give us an introductory statement about the technology involved. Come on, that's ridiculous.

mikhailfranco 10y ago

Already available for the UK, see: http://www.crashmap.co.uk/ http://www.crashmap.co.uk/

coldcode 10y ago

Is it possible to make such a map for homicides? Does the data exist with sufficient location information?

danso 10y ago
The FBI Uniform Crime Report and/or NIBRS may be the most comprehensive/granular data there is on homicides nationwide, but I don't think there's incident-level geography: https://www.icpsr.umich.edu/icpsrweb/NACJD/NIBRS/ https://www.icpsr.umich.edu/icpsrweb/NACJD/NIBRS/ Counting homicides, and even determining what exactly is a homicide, is not as clear as one might think: http://contentsmagazine.com/articles/homicide-watch-an-interview/ http://contentsmagazine.com/articles/homicide-watch-an-inter... Not that many agencies post the data themselves. Surprisingly, the NYPD does post it as part of their felonies dataset: https://data.cityofnewyork.us/Public-Safety/NYPD-7-Major-Felony-Incidents/hyij-8hr7/data https://data.cityofnewyork.us/Public-Safety/NYPD-7-Major-Fel...
- TillE 10y ago
  Good find with the NYPD link. I've seen New York data before that just went precinct by precinct, but this has exact latitude and longitude.

danso 10y ago

have a love-hate relationship with the NHTSA database. On one hand, it covers 40 years of data, and unlike virtually every other long-running dataset in existence, it keeps not only a relatively standardized schema, it publishes a all-in-one user manual that covers every year (and any changes between them); most places publish a new PDF for every year, which means you have to read through each one. Even better is that when they make changes or additions to their methodology, they publish an auxiliary dataset that you can use to retroactively update old datasets. But then for some reason, they throw out all rationality when it comes to naming files and fields. It's as if there was employee who was old-school and was stuck in mindset of naming things under the 8-character all-caps limitation. And then someone else thought, "Fuck this", and went the entirely opposite direction by naming files with long titles and spaces, and the two employees had a passive-aggressive argument that never got resolved over the decades. This makes scraping and collating the data a real pain in the ass. But compiling the data got a lot easier when I realized that wget works on FTP sites. Here's a mirror of the FTP site (around 1.7GB zipped) that I put up on Github (still working on getting everything together in one database): https://github.com/wgetsnaps/ftp.nhtsa.dot.gov--fars https://github.com/wgetsnaps/ftp.nhtsa.dot.gov--fars

laurent123456 10y ago

Isn't it pretty much a US population density map (if it's not, I can't quite see the difference)? If there are differences, it would have been interesting to display the number of accidents in an area as a proportion of the population.

thr0waway1239 10y ago

Would it help to use data like yearly per capita consumption of gasoline by state [1] (as a proxy for miles driven per person) in addition to the existing data? Would that make a difference and shed any more insight? [1] http://www.statemaster.com/graph/ene_gas_con_percap-energy-gasoline-consumption-per-capita http://www.statemaster.com/graph/ene_gas_con_percap-energy-g...

yaakov34 10y ago
You can get vehicle miles driven by state directly, and also such data as fatalities per road user and per miles driven: http://www.iihs.org/iihs/topics/t/general-statistics/fatalityfacts/state-by-state-overview http://www.iihs.org/iihs/topics/t/general-statistics/fatalit... However, you won't get much insight from plotting this data geographically: a table (as in that link) is enough. Basically you get exactly what is expected: Daniel Patrick Moynihan's "Law of the Canadian Border" - southern states have more social problems. If you want high-resolution geographical data for purposes such as finding problem roads, that would be a lot more difficult - you need to have a graph of the road network (from e.g. Open Street Map), with traffic data attached to the arcs of the network (I don't know of any public access databases like that, although such data is commercially available for road planning) plus accident locations accurately mapped to the roads. I suspect it wouldn't be a quick project to do.
fastaguy88 10y ago
There is something clearly very wrong with this data, since is suggests that California has less than 1/10th the per capita consumption of New York, and uses less fuel on an absolute basis than Connecticut. The dynamic range in fuel consumption differs only 2 fold for the top 46 (of 51) states, but then drops more than 5 fold. Those last 5 numbers must be on a different scale.

Agustus 10y ago

I am struggling with what will be the purpose of this. Any project that I work on with traffic analysis, PD&E, or roadway design includes a crash analysis. The crash analysis includes an analysis of every accident within a five year period, identification of high crash locations and what caused the crash (high speed, inebriation, or a list of other options), and then what strategies can be adopted for the most impact in a benefit/cost analysis. Just looking at heat maps of crashes without inclusion of traffic volumes (one crash per million miles is nothing compared to an area of one crash per thousand miles traveled) becomes meaningless.