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Comment Re:No Teaching Experience? (Score 1) 46

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) 69

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) 361

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) 434

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 Oh, rats... (Score 1) 123

So they finally invented something that would make me seriously consider buying an Xbox. I hope they have it in the stores in time for Christmas. I can think of a dozen great uses for it -- killing flies, drilling holes through would-be burglar's shoes (feet inside), a new way to light the barbecue grill. In fact, who needs the grill? Next summer I can reprogram it to keep the squirrels out of my peaches at the same time it prepares me a tasty laser-grilled peach-fed squirrel for dinner out of the ones that move too slowly! One wonders if it is sensitive enough to keep a yard cleared of mosquitoes (without putting anyone's eyes out, of course, at the yard party).

rgb

Comment Re:Wait, physics doesn't work either? (Score 4, Interesting) 207

"Entanglement" is a philosophically difficult arena. According to quantum theory, there is just one wavefunction for the entire Universe. However, we as observers are part of that wavefunction observing another part of that wavefunction with a really, really, big chunk of the whole wavefunction effectively unobservable but still coupled to the observer (part of the wavefunction), the measuring apparatus (part of the wavefunction), and the "experiment" (yep, part of the wavefunction. Everything is "entangled", but quantum mechanics also predicts that large systems approximated with a random phase condition will behave like a classical system, and the usual rule is that we treat a measurement apparatus as a classical system that breaks the entanglement of a measured systems and forces it "unpredictably" into a separable state. But even this is words, not equations although random phase approximations are indeed equations and are used frequently in field theory.

The only coherent explanation of this that I am aware of is the process of:

a) Starting with a density matrix (or other representation) for "the Universe".

b) Use the Nakajima-Zwanzig approach of splitting the (fully entangled) density matrix up into two parts -- a "system" that you will continue to treat as a quantum system, and a "bath" -- everything else -- which would also include the measuring apparatus if you were trying to describe an experiment. One then accepts the fact that one cannot know or prepare the state of the bath (which is really, really big being the rest of the Universe and everything) and so one makes a statistical approximation of the bath (taking the trace) which essentially eliminates the pesky entanglement but also breaks useful things like unitarity and in a sense, conservation laws. One them creates projection-valued operators and transforms the equations for the system into stochastic or semiclassical equations of motion.

c) IIRC your final result is quantum mechanics for the system expressed as a non-Markovian integrodifferential equation that is almost impossible to solve. However, if one makes a Markov approximation (forces it to be time-local, delta-correlates time) you end up with a decent explanation for things like spontaneous decay as an "exponential" process rather than a punctuated unitary process. You go one way, you can make it into a Langevin equation, go another you can make it more like Fokker-Planck.

The lovely thing about this approach is that it renders moot all sorts of nonsense, such as EPR paradoxes and "wavefunction collapse". It is perfectly clear that in the Universal wavefunction no such paradox or collapse can occur. They are simply expressions of our ignorance of phase and state whenever we try to isolate some part of the whole and pretend that it is a standalone "system" that can ever be decoupled from everything else. Schrodinger's cat paradoxes disappear as there is no paradox in the Universal wavefunction, only when we try to project the state of the cat against our ignorance of phase and interaction with the outside Universe. The cat, if you like, cannot be entangled separately from its preexisting entanglement with the rest of the Universe, and we only get into trouble when we have to force it by partitioning the system in order to get a chunk small enough to work with.

Hope this helps. I doubt it will. Very few people seem to be in touch with Nakajima-Zwanzig and the Generalized Master Equation these days, and don't treat problems like this as OPEN quantum systems as opposed to closed systems with a classical measurement apparatus, which is a place you only get to on the far side of the N-Z GME ritual.

rgb

Comment Re:Mirrors (Score 2) 123

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: I fucking hope so (Score 1) 108

But that IS the market. That IS capitalism. It's not some external, malign force: that's what the market is.

If you want it to actually be good, you're talking about some form of direction, oversight or regulation to stop obviously stupid or broken things from happening.

That's not a market anymore. The market is the thing that stampedes towards the stupid because everybody's doing it. See 'stock market'.

Maybe you just don't like capitalism as much as you thought you did! :)

Basic is a high level languish. APL is a high level anguish.

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