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Comment Re:No Teaching Experience? (Score 1) 40

Some people are great at teaching, others are not.

I believe this is a self-perpetuating myth. What the data shows is that new teachers in America improve rapidly over the course of about three years, after which they are about as good as they'll ever be. So it's certainly not the case that some people are just naturally teachers; great teachers have to learn the craft through practice, and that learning comes after they finish their official training.

But maybe what we're seeing is that it takes teachers three years to reach their inborn teaching potential, after which they no longer are able to learn anything more that might help them. My question is, how do we know that? How do we know that American teachers are actually completely incapable of becoming better teachers after three years of in-classroom experience?

We don't know. The remarkable thing is that until very, very recently, very few American school systems have actually attempted to systematically improve the performance of their teachers through observation of what they're doing in the classroom. They may have "professional development" where they get more of the same kind of theoretical training they got in education school, but they usually don't follow up to see how the teacher actually puts that to use, or even to identify bad habits the teacher may have developed over the years, or good habits he hasn't. In my kids' school system kids are sent home early on "professional development days" so that working with actual students won't get in the way of a teacher's skill development. It's like trying to make someone a better baseball hitter by banning bats and balls from training and simply talking to players about the theory of biomechanics.

Imagine you own a factory and your assembly line is turning out too many defective widgets. How would you address that problem? Would you send your engineers to a seminar every year on manufacturing theory and ask them to make design changes when they came back from that seminar? Or would you go over the assembly line with a fine tooth comb? While the seminar idea has it's merits, it's too slow and it'd take sheer luck for the seminar to hit on the particular problem that's affecting the line.

In America we have a simple model for improving the teaching at a bad school: fire the bad teachers and hire better ones. But imagine, just for a moment, it is possible to use empirical methodologies to improve the performance of any teacher. Imagine for a moment some bad teachers could be transformed into mediocre ones; some mediocre teachers into good ones; and some good teachers into great ones. In a world where that was possible there'd still be a place for the hire and fire strategy, but relying on that strategy exclusively leads to two unfortunate and unnecessary results: (1) Poor districts have to make do mostly with inadequate teaching and (2) teaching in rich districts tends to be adequate, but great teaching remains uncommon.

Sound familiar?

Comment Re:Because this will be unlike Biosphere 2 how? (Score 4, Informative) 68

To answer your question, smaller habitat, no experiment at maintaining atmospheric composition, outside excursions in "space suits" etc. Its not very much like Biosphere II.

As for why not under the sea or Antarctica I can give at least three reasons. (1) cost of building, transporting and maintaining the habitat; (2) all the support and research personnel live in Hawaii, above water; (3) the research objectives don't require putting the experiment in a dangerous or inaccessible place.

Now someday when we have an actual habitat design along with all the actual support systems we plan to send to Mars, a trial on top of a super high mountain would make sense as a kind of Mars analog. But we don't have such stuff to test so we don't need the Mars analog with all the expense and complication.

Comment Re:Furthermore, Saudi Arabia must be destroyed (Score 4, Insightful) 359

Not everyone in Saudi Arabia are bedouin; in particular the ruling House of Saud is descended from town dwelling Arabs.

I'll go out on a limb and guess that not everyone in Saudi Arabia is worthless. Even people involved in managing their oil. And as for the elite they don't seem to be worse than anyone else who's inherited oil-based wealth; they've managed that for the long term benefit of themselves and their families. If they're ostentatious with their wealth, well they have a lot of it and it hasn't bankrupted them yet.

So there's no rational reason to want to destroy Saudi Arabia. But there's every reason not to want to be so dependent upon them.

Comment Re:A simple test is in order (Score 1) 432

Well, this is a bit like parents who take their kids to get vaccinated and a few hours later that kid exhibits the first signs of autism. It's an immensely compelling coincidence. You'd have to (a) know that autism symptoms often have a rapid onset and (b) realize that when they do they can follow any commonplace childhood event. Even if you did it'd still be hard to shake the suspicion if it happened to your kid.

Somebody points a IR remote at your friend; he gets up and has a brief moment of orthostatic hypotension -- also known as a "dizzy spell" brought on by a sudden drop in blood pressure -- just at the moment the guy pushes the button. Orthostatic hypotension can happen to anyone, but if your friend isn't otherwise prone to it that can be a very compelling coincidence; and many of the symptoms of hypotension can be reproduced by psychological stress.

If something like that happens to you people will say, "oh, it's all in your head," but the thing is that all suffering is inside peoples' heads. One of the worst kinds of pain you can have is passing a kidney stone, but if you happen to be in a coma at the time you won't feel a thing. Distress produced within the brain is indistinguishable to the subject from distress produced outside the brain. Having an external explanation for that distress can make someone feel like they have some control over what is a disturbing experience, and shooting holes in that explanation isn't going to help unless you can offer them a better handle on it.

Sometimes I think we'd be better off if we just brought back shamans and witch doctors.

Comment Re:Mirrors (Score 2) 121

I don't think you could make the reflective surface perfect enough to make the drone positively laser-proof, but I think a reflective coating would certainly reduce the laser's effective range. Analogously you can't nuke-proof an aircraft, but in the Cold War they were often painted "anti-flash white" to help them survive a bit closer to a detonation.

Comment Re:Which is why (Score 1) 252

Well, as far as Atkins is concerned, diet research is really, really hard and expensive to do right. I know because when I was an MIT student one of my jobs was office boy in the Food and Nutrition group, and I saw how hard it was. In one of the studies, research subjects were given a duffle bag from which all the input to their digest systems came, and into which all the output from the same went, for six bloody months.

Of course not every study needs to be that rigorous, but diet is one of those areas where the public needs lots of informed opinion but the funding for research is grossly inadequate to meet that need.

By the way, the current state of research seems to be that carbohydrate restricted diets work well in the short term but have only modest success in the long term.

Comment Which is why (Score 2) 252

... you don't make any important decisions based on a single paper. That's true for hard sciences as well as social sciences.

Science by its very nature deals in contradictory evidence. I'd argue that openness to contradictory evidence is the distinguishing characteristic of science. A and not A cannot be true at the same time, but their can be, and normally is, evidence for both positions. So that means science often generates contradictory papers.

What you need to do is read the literature in a field widely so you can see the pattern of evidence, not just a single point. Or, if you aren't willing to invest the time for that you can find what's called a review paper in a high-impact factor journal. A review paper is supposed to be a fair summary of recent evidence on a question by someone working in the field. For bonus points read follow-up letters to that paper. Review papers are not infallible, but they're a heck of a lot more comprehensive than any other source of information.

Comment Re:That would be penny wise and pound foolish (Score 1) 375

Well, a lot depends on how your actions fit into your long term vision, if anything. "We'll just rebuild this neighborhood and everything will be hunky-dory" is obviously not a long term plan.

The reason the Netherlands flood control makes sense is that the value of 25% of their country's land area far outweighs the cost of reclaiming it, as simple as that. When the net present value of keeping the flood waters off a piece ofland exceeds the net present value of the use you'll get from it, then it's time to abandon piece of land.

Comment Re:Exaggeration is not Necessary (Score 1) 375

Well, if you *insist* on being pedantic, what they mean is "It's not going to stop before it causes a degree havoc most people would find inconceivable."

I think they kind of expect people to understand they're not claiming that the water levels will rise, drowning the Moon, inundating the Sun, and eventually filling up the entire universe.

Comment Re:"...need to be prepared..." (Score 4, Insightful) 375

Sure. Or sooner if you are economically tied to businesses or people near the coast; or businesses or people not near the coast; or businesses or people not near the coast but dependant on others that are. That's the downside of living in a modern economy. I didn't hold any toxic mortgage backed financial instruments, but I sure felt the pain when the capital markets went tits up in 08.

Comment Re: No one should *ever* wonder why... (Score 1) 275

The lack of understanding what a conservative is on slashdot never ceases to amaze me. Its called smaller government and enforce laws that are already on the books instead of creating new ones.

There you go, you explained your own mystification away. You define the conservative program by what conservatives want. Everyone else defines it by what the people conservatives vote for do when they get into office, which is spend money and make government even more intrusive.

Comment I propose a solution. (Score 1) 235

Any time the cops stop an autonomous car they have to pay the owner of that car $1000, no matter what the reason for the stop. Compared to the legal costs of what comes after a legitimate stop, that's nothing. But it would dissuade police from developing a pattern of frivolous stops.

Comment Re:No one should *ever* wonder why... (Score 3, Interesting) 275

Well, I agree government is dangerous -- so is anything that is powerful. Max Weber defined the state as the organization that has a monopoly on violence.

But the blame isn't with the liberals, or the conservative libertarians, neither of whom want this kind of data collection. It's with the conservative authoritarians who want to expand the power of the police.

Comment Re:Clickbait title ? (Score 2) 235

Well, I think it's more complicated than that. People are not just ignorant of the limitations of knowledge, they're ignorant of the limitations of ignorance.

In fact, I'd say faulty appeals to ignorance are much more common here than faulty appeals to knowledge. People will say "How can we know X when we don't know Y?" when in fact it's quite possible to know X without Y, and in any case we actually know a lot more about Y than the poster thinks.

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