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General Road and Highway Discussion
(11-14-2017, 10:52 PM)Pheidippides Wrote: Plus, something doesn't feel right about the fact that they are looking at fatalities on the regional road network (~700km), but using the entire regional population as the denominator.

I think I figured out what bothered me about the use of the entire region as a denominator.

If you are going to use all of the population of a geographic area in the denominator then you need to use all of the fatalities in a geographic area in the numerator; not just the ones on regional roads (I understand that the region only has control over its roads, and there is no way of knowing the true size of the population that uses regional roads so this was the best approximation they could do, but I think to most people who hear this reported would be misled because they don't understand the differentiation between a city road and regional road).

According to public health, deaths to Waterloo residents (not deaths occurring in the region on regional roads) resulting from "land transport" injuries occurred at a rate of 4.8 / 100,000 in 2012 (where "...land transport collisions are predominantly represented by motor vehicle collision deaths, but also include deaths in collisions involving other modes of land transportation such as trains, street cars and animal-drawn vehicles...").

So that is higher than Sweden's rate in 2012 and I think that is excluding cyclist and pedestrian deaths.
Everyone move to the back of the bus and we all get home faster.
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I don't think the problem is in using the entire population as the denominator or just fatalities on regional roads as the numerator.  That seems most consistent with the Swedish numbers to me.  

That doesn't mean its an apples-to-apples comparison though because like you say the usage of the road network is going to vary and even the types of roads are going to be very different.  Something like fatalities per mile driven seems more fair.  And you could also probably break that down by urban, rural, highway, etc. roads.

In the end though, these comparisons are always going to be pretty flawed.  Looking at the trends can be useful, but.... if you're just looking at any single high-level comparison its almost always going to be flawed.
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(11-16-2017, 08:18 AM)Pheidippides Wrote: According to public health, deaths to Waterloo residents (not deaths occurring in the region on regional roads) resulting from "land transport" injuries occurred at a rate of 4.8 / 100,000 in 2012 (where "...land transport collisions are predominantly represented by motor vehicle collision deaths, but also include deaths in collisions involving other modes of land transportation such as trains, street cars and animal-drawn vehicles...").

So that is higher than Sweden's rate in 2012 and I think that is excluding cyclist and pedestrian deaths.

I do believe that would include pedestrian and cyclist deaths, assuming a motor vehicle was involved. Now, if a pedestrian was killed by a speeding bicyclist, that might not be included but I don't think that would be very common ...
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(11-16-2017, 09:20 AM)SammyOES Wrote: I don't think the problem is in using the entire population as the denominator or just fatalities on regional roads as the numerator.  That seems most consistent with the Swedish numbers to me.  

I will have to disagree. Sweden is measuring all of the deaths on all of its roads so it makes sense to use the total national population as the denominator. The region is only measuring collisions that resulted in one or more death on regional roads. The actual unit of measure is different (fatalities vs. fatal collisions).

Also, regional roads make up 20% of the road network within the region (the rest being city, province, or private) and 60% of the total length of those regional roads is in rural areas (defined arbitrarily as being in the four townships). On top of that 11% of the region's population is rural. So they are looking at a fraction of the road total road network, and the largest portion of the regional network is used by the smallest portion of the population.

If you look at the urban parts of Sweden the rates are around 1.5/100,000, the rural areas are around 6.7/100,000 for 2016.


Also, I checked the public health definition.

Fatalities from "land transport" injuries includes:
Motor Vehicle Collisions (Traffic and Non-traffic)
Pedestrian (Motor-vehicle Traffic only, Motor-vehicle Non-traffic, Other, non-motor vehicle)
Cyclist (Motor-vehicle Traffic only, Motor-vehicle Non-traffic, Other, non-motor vehicle)
Public Transportation (Bus occupant, All railway train or railway vehicle transport accidents, Street car occupant)
Off-road transport accidents (Both traffic, non-traffic including drivers, passengers and unspecified occupants of snowmobiles and Other all-terrain or off-road vehicle..

Where a traffic accident is one that occurs on a public highway/road, and a non- traffic accident occurs in another place other than a highway/road. 

So it actually would include pedestrian vs. cyclist, or pedestrian vs. pedestrian, or cyclist vs. cyclist fatalities (however rare), but also includes other modes of transport and locations that would be beyond the traditional road network. So probably a slight overestimation, but better than what was presented.
Everyone move to the back of the bus and we all get home faster.
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I've never heard of a "fatalities per lane kilometre of road" statistic before. I thought these things were usually measured as the number of fatalities per kilometres driven, walked, biked, whatever.
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I drove by the closed part of Krug last night. It is still closed, but I wonder if it may be opening shortly, as, quite frankly, it looks like it could be safely opened to traffic already. Lighting wasn't that great and I was only able to give it a quick glance, so I might be wrong.
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(11-16-2017, 09:22 PM)Pheidippides Wrote: I will have to disagree. Sweden is measuring all of the deaths on all of its roads so it makes sense to use the total national population as the denominator.

You still want apples and oranges though. Not all of their national population uses the roads. So if you include the people that don't use the roads in case 1, it makes sense to me to do the same thing in case 2.

(11-16-2017, 09:22 PM)Pheidippides Wrote: The region is only measuring collisions that resulted in one or more death on regional roads. The actual unit of measure is different (fatalities vs. fatal collisions).

I agree this is wrong.

(11-16-2017, 09:22 PM)Pheidippides Wrote: Also, regional roads make up 20% of the road network within the region (the rest being city, province, or private) and 60% of the total length of those regional roads is in rural areas (defined arbitrarily as being in the four townships). On top of that 11% of the region's population is rural. So they are looking at a fraction of the road total road network, and the largest portion of the regional network is used by the smallest portion of the population.

Right, but changing the population denominator doesn't address this fundamental problem. It just makes it bad in a different way (and we have no real way of knowing if the 'badness' is better or worse). The way to address it is to use a metric that actually incorporates the amount of usage.
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(11-17-2017, 09:26 AM)SammyOES Wrote:
(11-16-2017, 09:22 PM)Pheidippides Wrote: I will have to disagree. Sweden is measuring all of the deaths on all of its roads so it makes sense to use the total national population as the denominator.

You still want apples and oranges though.  Not all of their national population uses the roads.  So if you include the people that don't use the roads in case 1, it makes sense to me to do the same thing in case 2.

Emphasis mine. I mean, people driving less or fewer people driving seem like completely sensible ways to get to Vision Zero.
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Erb/Caroline is such a disaster right now. If you want to turn Left from Bridgeport, onto Erb - good luck! Since it’s a single lane on Erb now, and there’s a stop sign at king, everyone turning right off of Caroline obviously gets to go first, so only one car at a time can (barely) turn left.

I biked through the area on Sunday and watched 3 cars in a row turn left from Caroline onto Erb (illegally). The icing on the cake was that dude in car 2 actually honked at car 1 to go through.
For daily ion construction updates, photos and general urban rail news, follow me on twitter! @Canardiain
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(11-19-2017, 11:40 PM)mpd618 Wrote:
(11-17-2017, 09:26 AM)SammyOES Wrote: You still want apples and oranges though.  Not all of their national population uses the roads.  So if you include the people that don't use the roads in case 1, it makes sense to me to do the same thing in case 2.

Emphasis mine. I mean, people driving less or fewer people driving seem like completely sensible ways to get to Vision Zero.

Sure, I agree. But the point isn't whether the metric is a good one in a vacuum, just about the best way for the Region to calculate a metric comparable to the one from Sweden they're using.

You shouldn't include the total possible population in one case and not the other. In both cases you're going to have a percentage of the population that doesn't use the roads you're looking at. The fact that there are likely significantly different usage rates doesn't mean you should use a different methodology for calculating the metric. It means you should probably use a different metric altogether (or much better, a set of different metrics).
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If we're still talking about Krug street construction , it is apparently open to vehicles. What I heard.
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