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Comment Re:Correlation is not causation (Score 1) 490

The point is that forcing students who wouldn't otherwise take Algebra II to take it might not provide as much benefit as the correlation seems to indicate if there is not a direct causation, but instead a third variable effecting both. There may be root factors that occur much earlier in life that determine whether a student ends up being the type that would take Algebra II, and benefit from it - it may be more worthwhile to continue investigating to figure out what that root factor is.

Comment Re:Noooooooooo!!!!!!1111!11! (Score 3, Interesting) 541

It's kind of an interesting game theory problem - from the perspective of an individual parent, the risk of not vaccinating only their child is relatively low, given that they are assuming everyone else will be vaccinated. if there is even a tiny perceived danger in getting the vaccine (real or not), than the rational choice may really be to not be vaccinated. Unfortunately, this can lead to a Nash equilibrium, in that the outcome for the entire population is worse if everyone were to make this choice, similar to the prisoner's dilemma problem. From the perspective of the entire population, for example a public health official, it obviously makes sense to vaccinate everyone, even if there is some very small risk from the vaccine, as long as that risk is smaller than the risk of getting a disease without the vaccine.

Comment Re:Stunning (Score 1) 206

Creativity is often just finding a solution to an NP-hard problem, for example writing a song. Most people can tell if a song is enjoyable to listen to or not, but they can't necessarily write their own. They can listen to many songs and determine which are most pleasing. A songwriter has the special ability of assembling a song that meets the requirements of being pleasing by some method that is more efficient than simply testing each combination of random notes. Sudoko is similar, it is easy to verify that a given solution is correct. One solution method would be to keep testing different combinations of numbers until a solution is found, but there are more efficient methods using some heuristics based on the other numbers present, or experience from solving previous puzzles. The question might be whether there is something fundamentally more intelligent about things that humans create - songs, literature, etc, compared to a series a numbers in a Sudoko puzzle.

Comment Re:So the weak point in the system is...... (Score 3, Informative) 218

I think the reason is that on a small scale, it is possible to control a quadcopter or quadrotor by changing the relative speed of the rotors, which is much simpler because there is no cyclic pitch, or swashplate mechanism, but this technique doesn't scale well. On a man-sized quadrotor, it would be difficult to accelerate and decelerate the rotors fast enough to have agile control, and so the use of cyclic pitch becomes the better method to control thrust. If you are using cyclic pitch, then it becomes simpler to have one (or 2) rotors instead of 4. Also, when a rotor tilts, it generates large gyroscopic forces. On a small model, these are small compared to the strength of the rotors, but on a man-sized vehicle, the rotors need to be able to "flap" in order to reduce stress on the blades, which again is simpler if you only have to deal with one rotor.

Comment Re:idiots abound (Score 1) 1695

I don't think this is even about whether it is hate speech or not. The majority of the people in the world have tough enough skin and don't care, but unfortunately there are a few crazy people in Pakistan, who will definitely do real things that harm everyone else in the world as a result of this, such as recruit more terrorists, and kill innocent people. If the only risk here was whether this offends some people, then go ahead and do it, but at some point, we have to look at the risk vs. benefit of each option. If burning the books results in more killing in the world, and does not help in any way, then it's not a wise choice. Others have argued that it is cowardice to not burn the books - this might be true if there was some identifiable benefit from burning them, but making a choice that only leads to bad things is typically referred to as "stupid". Of course, the identifiable benefit to this guy might just be publicity.

Comment Re:Hmm (Score 1) 309

The question wasn't "why is he allowed to pack heat" the question was "why does he _need_ to pack heat." Of course people are allowed to carry guns if they feel it is necessary for protection, but many people would consider themselves more "free" if they can live a life that doesn't require a deadly weapon to stay safe.

Comment Re:Good news...? (Score 1) 296

The problem is that if there aren't enough disabled folks, then no businesses will have any motive to serve them, so the handicapped people will be severely limited in their options. Apparently when all things are considered, requiring businesses to be more accessible is viewed as being less of an infringement of freedom than completely preventing disabled people from functioning in society.

Comment Re:Gyroscopic effect? (Score 1) 197

A mass with angular momentum experiences a moment in a direction perpendicular to both the angular momentum, and the rate of change of the angular momentum. I'm not sure if I stated that correctly, I may be off, but what it means is that if the flywheel is mounted horizontally (the angular momentum vector pointed straight up or down) then when the car rolls, it will generate a pitching moment, and when the car pitches, it will generate a rolling moment. I don't know if it would be likely that the car would experience high enough pitch or roll rates for this to be a factor. A stabilizer could rotate the flywheel internally in the car pitch axis to generate a rolling moment when going around corners.

Comment Re:No real impact (Score 1) 874

Here is a hint, much of these costs will be embedded into items you purchase and you will have no way to avoid it.

Here is a hint, right now the pollution from the manufacture and use of all of these products is embedded in the air you are breathing, and you currently have no way to avoid it.

This is merely charging people for their actual use of public property - air - which has been overused. You will be charged no extra if you only use the air you breathe.

Comment Re:Nobody Knows (Score 1) 884

I have no idea how the specific control laws in the A330 work, but on other aircraft there is an artificial spring force that varies with airspeed and other factors to give the pilot a good feel on the controls for the particular flight condition.

From the chart at airbusdriver, it looks like there are backup mechanical controls for the elevator and rudder only. It says the elevator control is via a trim wheel, which would only allow very slow changes, and would be really awkward to try to regain control in a difficult situation.

The software should limit the control inputs to levels that won't break the aircraft at the given flight condition, but, if say the air data unit was malfunctioning, the control laws may have thought the aircraft was moving much slower, and given the pilot greater authority to move the rudder, and led to a structural failure. This is all complete speculation, but, just a thought.

Comment Re:Wrong (Score 1) 252

Yeah -- let's REQUIRE high schools kids to do menial crap that's approved by the Federal government.

Kids have always been required to do work at school, but this one thing which is more applicable to everyday life than most school work, is a problem?

Comment Re:Service Day? WTF? (Score 3, Insightful) 252

I think you are taking this a way too seriously. First, no one is forcing anyone, or even really compelling anyone to volunteer, if you don't want to do it, you don't have to, with no negative effects whatsoever.

I think the goal is just to make a time where it is more socially acceptably and when people are encouraged to do volunteer work. Many people might have a slight interest, or be unsure of how to get involved, so maybe this day will make that easier, and make them realize how to volunteer more often, out of their own free will.

The same goes for requiring some community service in school. In real life no-one can make you volunteer, but they also can't make you write papers or finish assignments. In school, you get grades for learning, and trying out some volunteer work can be educational.

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