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by throwaway1X2 3506 days ago
> Honestly speaking, I have enough of our politicians of disregarding scientific studies and expert analysis, but this is somewhat accepted.

The problem is, the linked article is not scientific. Yes, it links some studies and cherry picks a few sentences from them, but exactly in the way that media do in pieces like "Scientists have discovered 3 more ways make your road safer!".

For example, the article cites a study that says that higher speed is expected on wider straight streets between traffic lights. Then it says that there is no reason to not apply to other types of road (like not being straight? or maybe 20 other even unworded reasons, which is why scientists tests hypotheses and don't publish papers 'there is no reason this is not true' all day). Then it says that pedestrian hit at speed X have better chances than when being hit at speed Y. But does each car hit a pedestrian? By this same method you can say that blindfolded drivers will drive more slowly. Will it be safer?

Sorry, this is no science, this is pushing an agenda. It uses nice subtitle "The Studies: Rare but Conclusive" right before citing a paper, where even cherry-picked quote says it was statistically insignificant. It uses grand wordings to play as having all in hard data, but it stretches conclusions by untested implications. It doesn't compare costs and outcomes to other alternatives (optical speed "bumps", lenghtwise wave markings, etc.). It doesn't mention effects on driver fatigue (you have your nice slower speeds on several streets, but people drive half an hour through that and pay less attention elsewhere), it doesn't consider long term impact - many traffic solutions shows changes, because, well, they ARE changes. Some of them regress very quickly - e.g. make a few roads narrower? It is a change in both the temporal aspect (a week ago, the street was wider) and the citywise movement (you drive and suddenly the next road is narrower). Change several roads throughout the city and this mind trick will be gone, people will get accustomed and speed up, now on narrower street. What is the worst of this, is that five years from such a change, articles like this one playing it "scientifically" could compare the 'before' and 'after' and still claim decrease in accidents and deaths regardless of the true effect of the narrower road. All you need to do is:

- not account for changing vehicle park, where old cars full of sharp edges are scraped and newer cars are shaped all around accidents, there must be clearance between engine and bonnet, some bonnets even pop up, etc.

- not account for common driver assists (ESP, blind spot indicators, bird's eye parking view, rear passing traffic alarm, etc.),

- improving systems like autonomous braking (talking not only about Tesla, it has been out there for quite some time, it only needs to come down to cheaper cars),

- healthcare improvements, new methods, new apparatus.

All of these could make previously deadly accidents survivable or could prevent them altogether cooperating with the driver or even autonomously, regardless of whether you make your roads narrower or not. Accounting for all these effects is hard (not impossible) and it is beyond the level of "scientificness" often found in articles like these.

The article is simply the same politics as from politicians, only targeted to a little more sophisticated reader than the typical "experts found out X. end of article." articles from media, yet the reader must be one who doesn't orient themselves in science and politics of agenda pushing transportation-proposing-articles.

2 comments

Urban design, and transport in particular are intrinsically political subjects. You can optimise things in one way or the other in a rigourous way. But there is no way to objectively determine how to balance different issues. That has to be decided politically, and then a solution is "engineered". Using science to draw political conclusions is destined to bias however well informed the person. But there is nothing wrong with pushing an agenda.
Exactly. The author came across as smug and not credible, since he was clearly pushing an agenda. The first red flag was his straw man:

> Think about your behavior when you enter a highway. If you are like me, you take note of the posted speed limit, set your cruise control for 5 m.p.h. above that limit, and you're good to go.

I can't remember the last time I used cruise control, but it was definitely on a 200+ mile trip. If the author is such an un-engaged driver that he relies on cruise control every time he gets on a highway, I'd hate to think how lackadaisical he is when he's "only" going 40 MPH around town. Certainly drivers like this—to the extent they actually exist—would need encouragement to stay attentive. But pretending that everyone is this checked-out while driving isn't realistic (I've ridden with many drivers from all over the US in the last 20 years, and no one reaches for the cruise control right after getting on a highway).

It may be the case that narrower lanes is the way to go, but the tone of this article undermined the persuasiveness of the evidence cited.

What correlation does using cruise control have with not paying attention? I think that's a strawman. I certainly feel much safer on the highway with people driving at a relatively constant speed, rather than gunning up to 80 mph, then falling back to 60 because they are fiddling with their radio or taking a call, then accelerating back up.

> Think about your behavior when you enter a highway. If you are like me, you take note of the posted speed limit, set your cruise control for 5 m.p.h. above that limit, and you're good to go.'

This is exactly what I do, every time. Except I set it at the speed limit, and trundle along in the right-hand lane. You get there just as fast, and don't run the risk of attracting any attention from the five-o.