Transportation risk
March 27, 2008
Data from the Bureau of Transportation Statistics (1, 2, 3) show that while using cars and trucks for transportation is continuously becoming safer, transportation using motorcycles has become considerably more risky in the last decade. It now about 50 times more risky to travel using a motorcycle than it is to travel by car or truck.
April 8, 2008 at 8:39 am
“transportation is continuously becoming safer…” – but to whom? The data presented here excluded all the pedestrian, cyclists, etc. fatalities in accidents caused by cars/trucks.
Specificaly, it was found that trucks pose low accident risks for their drivers but are relatively high accident risks for other road users.
April 8, 2008 at 5:24 pm
Hi Erel,
I only included fatalities of vehicle passengers in order to compare the risks assumed by the persons making the the choice of vehicle type. Indeed, many of the motorcycle accidents probably involve collision with a car or a truck.
Including pedestrians and pedalcyclists in the cars and trucks statistics would not change the picture much. As you can see in one of the tables I linked to, pedestrian and pedalcyclist fatalities are a fraction of the car and truck passenger fatalities (about a fifth), and their numbers are slowly falling as well.
April 8, 2008 at 7:19 pm
Yoram,
One may argue that making statistical comparisons of risk is itself a risky business…
I generally agree with this observation made by you but still believe that in order to represent the risk important that the pedestrian and cyclist data will be represented in order
On a different matter:
Why fatalities are measured against the travel distance rather than, for example, against the travel time? Or against the number of journeys made by the traveller? Or against the number of licence-holders? Which of them provide a better measure of risk?
Using the distance-based measure, the risk for users of different modes of transport, travelling in relatively high speeds, might be under-represented compared with the risk for the users of the slower modes of transport.
I am not saying that the conclusion (“transportation using motorcycles has become considerably more risky in the last decade”) is wrong, only that a different sort of analysis may be required here.
April 10, 2008 at 4:39 am
Each of those rates would be relevant in a different context. Risk per distance unit is of interest when comparing alternative modes of transportation for a given trip or set of trips. If the total distance is fixed, then the travel speed is not of interest. If, on the other hand, you decide in advance to spend a fixed amount of time traveling, then the quantity of interest is fatalities per unit of time.
It is true that the availability of modes of transportation that are safe, cheap and fast tends to increase the total distance traveled. Thus, owning a car may put you at increased risk even though traveling by car is probably safer per unit distance than traveling by foot.