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Comment Re:Most (Score 1) 249

"Discrete mathematics" -- I don't think that word means what you think it means.
(I know a whole lot more about discrete mathematics than I do about statistics or climatology.
Look it up on wikipedia, see if you see very much at all about sampling theory or statistics.
Yes, they DO mention discrete probability, but it is a tiny corner of the whole.)

Comment Re:IPCC AGW predictions FAILED (Score 2) 249

Don't know if you've ever compared the three amounts of energy, (1) solar energy incident on the earth in a year, (2) heat of fusion of the Greenland and Antarctic ice caps (i.e., energy to melt them, assuming they are at 0C and frozen) and (3) the amount of energy required to heat the oceans by 1 degree C. The ratios are roughly 1 : 1.8 : 0.9. (My arithmetic: http://dr2chase.wordpress.com/2012/02/04/numbers-that-were-larger-than-i-had-imagined/ )

For me, this was simultaneously stupefying, scary, and annoying. Scary because the thermal mass of the ocean is incomprehensibly large, which means that burps and blips in the South Pacific can overwhelm any minor atmospheric effects, and annoying because in any discussion with internet "experts", no matter how correct it might be to blame the ocean, neener-neener-Al-Gore-said-it-would-be-hot-by-now.

Comment Re:Protecting pedestrians from bad drivers (Score 2) 136

For either sense of the word "blind", if there's a pedestrian and it's a crosswalk, the law says you're supposed to stop for them. They are not supposed to stop for you; they have right of way. If visibility is not so good, that is presumably because the highway department assumed that you, an allegedly safe driver, would reduce your speed correspondingly so that you could always see the pedestrian that you are legally required to stop for. If you are ever honking at a pedestrian in a crosswalk, or a blind pedestrian crossing a street anywhere, either your brakes have failed and you are warning them of this unusual hazard, or else you are doing it wrong.

If someone's approaching a stop sign at a high rate and it doesn't look like they are going to stop, the safe thing to do is brake ahead of time. For honking at them to work properly, many things have to happen in a timely fashion -- they have to hear you (dead people can be licensed), they have to figure out you are honking at them, they have to figure out *why* you are honking at them (presumably, if they saw the stop sign, they would stop for it, right?), and they have to react. Ideally, if the reason they were not stopping was that their brakes had failed, they would already be honking their horn.

The overwhelming use I observe for horn use is "the light is green and you're not moving". That is not a safety issue -- cars not moving is in fact quite safe, albeit frustrating.

Comment Re:Protecting pedestrians from bad drivers (Score 1) 136

I don't suppose that my car's computer could have a little chat with your car's computer, maybe they could coordinate?
Seems like one of the very first things that smart-ish cars should get right is not running into stuff that is right in front of them.

And we have that problem now, with ABS. A couple of years ago, renting a car, junk flew off a truck in front of us and everyone stopped fast. The guy behind me did not have ABS. Oops. Royal pain with all the paperwork, but in the end, yes, it was their problem.

Comment Re:Protecting pedestrians from bad drivers (Score 1) 136

I don't think the pedestrian does know that you will stop in time, but a certain number of pedestrians aren't paying attention and this could help them. Defense in depth, after all. The few crashes that I've watched happen (and one I heard recounted in which a cousin was killed) all involved multiple coincident screwups. Not one was caused by a single point of failure. Cars currently kill thousands of pedestrians each year; there's plenty of room for improvement.

And we do manage to (eventually) design safety devices that result in a solid net reduction in harm, so I imagine we could get this one working pretty well, too. Airbags we (finally) got right. Seatbelts are low-tech and effective. ABS braking is pretty startling compared to old-style (I've never owned a car that had it, but I always check out the new features in rental cars).

Comment Protecting pedestrians from bad drivers (Score 3, Insightful) 136

You don't "protect" the pedestrian by telling the bad driver to activate his brakes. Instead, automatically activate the brakes, take the bad driver out of the loop.

This is similar to my gripe about people who think that a horn is a useful safety device -- as if the guy who you are beeping at is going to listen the horn, figure out that it applies to him, and figure out what he is doing wrong, fast enough to make a difference. Better to simply assume that he's an idiot, and work around him.

Comment Re:Not really (Score 1) 732

I am not at all sure I follow your logic. If not for 9/11, we'd have none of this security theater nonsense. People born post 9/11 are affected by this even if they were not around on 9/11 (and relatively few people were directly affected -- closest I get is multiple friends-of-friends, and I live in a Boston suburb), and it may cause them to change their travel preferences. Most people experienced it only on television -- is there a difference between seeing it live, versus on video? It seems like you are make a fine distinction that is not necessarily justified.

Comment Re:Not really (Score 1) 732

I think you need to explain to this poor dumbass how air resistance has any effect on using the tachometer (that's engine rpm) to estimate speed when the speedometer has hit its limit. Normally when you hold the gear constant, especially with a manual transmission, you can observe an exact correlation between road speed and engine rpm -- for example, "speed in kph = revolutions per minute times .045".

Comment Re:Not really (Score 1) 732

I don't understand why you would only count deaths of people alive on 9/11 -- if some sort of idiotic cultural reaction to 9/11 resulted in a permanent increase in early deaths, that effect applies to people born afterwards. These events are not single-points of change -- we still have our rainbow alert system, we have all the security theater at airports to remind us that Evildoers might want to sneak onto airplanes, etc.

Comment Re:No need for cameras. (Score 1) 732

They make my head sweat, quite a lot, even in the (20F) winter -- on a bike. No physical activity in a car, hence the main objection I have is removed in that case.

The other problem with bicycle-helmet-smiting is that it is not rational nanny-state behavior; it is far, far more sensible (which is not to say that it actually comes anywhere near "good idea", it is merely a less awful idea) to withhold medical treatment for heart attack, stroke, and diabetes from people who don't ride bicycles -- the yearly mortality rate (not the sickness and chronic medical cost rate) is 39% higher for the non-bike-commuting population. That's a much bigger effect than crash risk. If you mandate helmets but don't do anything about the lack of exercise, all you've got is innumerate moralizing nonsense.

Comment Re:Not really (Score 1) 732

Though I think all the groaning and moaning about automatic speed limits is amusing, I do agree. It's much more important to enforce the low speed limits in residential areas than it is to enforce the high speed limits on highways. At the same time, you're going to be stuck with speed differentials on the highway, no matter what, and one thing that speed limiting equipment would do is reduce them -- though you would still have the slowpokes, you would not have any autos driving above the limit. By your logic, that should increase safety, right? (I know that's not the conclusion you were after.)

Comment Re:No need for cameras. (Score 1) 732

But the same should then also be true of driving without a helmet -- as many safety devices as cars have, they still manage to be the largest (US) source of fatal head injuries, and 23% of car occupants who die in crashes only suffer head (major) injuries. Another 18% die from a combination of head and thorax injuries.

Biking's just not that dangerous, compared to lots of other stuff we do already and think is quite safe. It's about twice as dangerous as driving per trip, maybe less dangerous per hour (one old study, from Failure Analysis Associates concluded that) and far safer than riding a motorcycle (per-trip, 25x higher risk). The health benefits are also substantially larger than the crash risk, probably somewhere between 5x and 20x.

And before you claim that my figures must be buggy -- how sure are you that your gut-level "it will never happen to me (in a car)" estimates are correct, versus risk factors compiled by health and safety agencies? And the "but I don't drive drunk or at night, therefore my risks are lower" adjustment to risks -- you think that drunks in the dark aren't disproportionately represented in bicycle fatalities?

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