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Comment by jerf | Hacker News Reader

"This is a great development, considering the recklessness of many young drivers and their relatively high accident rates."

Is it? Is it working? I just spent five minutes on Google trying to answer that question, but if it's out there it's buried under megabytes of high-Google-juice warnings about teenaged driving.

It's only a positive development if it's working. If it isn't working, then it's just an expensive imposition sucking away time and funds that could have been spent on something more productive. But I honestly don't know which is the case. Anyone have a better bead on analysis than I do? I think it's an interesting question. Many of these programs have been going on for long enough that there ought to be an answer out there somewhere.

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It looks like it is actually working. I pulled this data from the CDC's website[1] for auto-related fatalities for Americans aged 14-19 (population is total # of teenagers):

YEAR DEATHS POPULATION

1999 5,508 24,099,614

2000 5,561 24,272,121

2001 5,513 24,515,654

2002 5,943 24,742,879

2003 5,582 25,019,050

2004 5,564 25,510,811

2005 5,234 25,839,430

2006 5,186 26,116,159

2007 4,986 26,327,320

2008 4,067 26,408,974

2009 3,514 26,378,690

2010 3,159 26,206,325

[1]http://webappa.cdc.gov/sasweb/ncipc/mortrate10_us.html

Doesn't that need to be normalized by the change in the auto fatality rate for the whole population? I recall that fatalities have dropped off for everyone because of advances in safety technology in cars.

Another factor to consider is the continual improvements in roads. For example, when I was younger, the main local freeway narrowed to two lanes with a dangerously sharp turn between me and the nearest major city. Over the past decade+, the freeway has constantly widened, with easier, more sweeping turns, better banking, better surface texture and maintenance, etc.

It probably should be normalized in many different ways (but if we hypothesize that teenagers are dangerous drivers, taking teenagers off the road would reduce both the teenage fatality rate and the fatality rate of the general population).

Couldn't these things just be increasingly safe car designs? When I started driving in 2005 side curtain airbags weren't even that common much less all the safety features we have today.

We can use the data here to normalize against the decrease in auto fatalities across the entire population: http://www.census.gov/compendia/statab/2012/tables/12s1103.p...

From 2000 to 2009, the # of traffic-related deaths per 100,000 resident population dropped by 26%. Assuming the decay is exponential, that's about 3% per year. In contrast, the # of teen deaths dropped by about 4.5% per year.

So we can reasonably conclude that teenage auto-related deaths are falling at a faster rate than overall auto-related deaths.

+1 for the effort. Interesting development

Analysis and responses like this is what makes HN great.

Thank you.

What I'm curious about is the fatality rates for new drivers regardless of age.

Is the fatality rate for all inexperienced drivers dropping the way it is for teenagers? If not, that suggests that the apparent improvements aren't so significant as they seem. In particular, social and regulatory changes that make it more difficult for teenagers to drive, but not for young adults may only shift what age group the problem affects.

The other sibling comments on the interpretation of this data are accurate, but my biggest problem with it is this:

If you reduce the driving privileges of people with blue eyes, I'm sure that the auto-related fatalities of blue-eyed people would decrease.

I'm not sure of the correct way to measure the success of driving restrictions, but I would suggest that it is something other than this type of statistic.

I don't think that's incorrect though.

If there exists a mushroom that tends to be lethal in even small quantities and its usage in recipes is restricted, then the fatalities caused by it will go down.

You might disagree with the method on deontological grounds, but you can't really deny that it is functioning well on consequentialist grounds.

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