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Comment p-value research is misleading almost always (Score 5, Interesting) 208

I studied and tutored experimental design and this use of inferential statistics. I even came up with a formula for 1/5 the calculator keystrokes when learning to calculate the p-value manually. Take the standard deviation and mean for each group, then calculate the standard deviation of these means (how different the groups are) divided by the mean of these standard deviations (how wide the groups of data are) and multiply by the square root of n (sample size for each group). But that's off the point. We had 5 papers in our class for psychology majors (I almost graduated in that instead of engineering) that discussed why controlled experiments (using the p-value) should not be published. In each case my knee-jerk reaction was that they didn't like math or didn't understand math and just wanted to 'suppose' answers. But each article attacked the math abuse, by proficient academics at universities who did this sort of research. I came around too. The math is established for random environments but the scientists control every bit of the environment, not to get better results but to detect thing so tiny that they really don't matter. The math lets them misuse the word 'significant' as though there is a strong connection between cause and effect. Yet every environmental restriction (same living arrangements, same diets, same genetic strain of rats, etc) invalidates the result. It's called intrinsic validity (finding it in the experiment) vs. extrinsic validity (applying in real life). You can also find things that are weaker (by the square root of n) by using larger groups. A study can be set up in a way so as to likely find 'something' tiny and get the research prestige, but another study can be set up with different controls that turn out an opposite result. And none apply to real life like reading the results of an entire population living normal lives. You have to study and think quite a while, as I did (even walking the streets around Berkeley to find books on the subject up to 40 years prior) to see that the words "99 percentage significance level" means not a strong effect but more likely one that is so tiny, maybe a part in a million, that you'd never see it in real life.

Comment The ultimate "man made earthquake" (Score 3, Interesting) 166

Russian analyst urges nuclear attack on Yellowstone National Park and San Andreas fault line

A Russian geopolitical analyst says the best way to attack the United States is to detonate nuclear weapons to trigger a supervolcano at Yellowstone National Park or along the San Andreas fault line on California's coast.

The president of the Academy of Geopolitical Problems based in Moscow, Konstantin Sivkov said in an article for a Russian trade newspaper on Wednesday, VPK News, that Russia needed to increase its military weapons and strategies against the "West" which was "moving to the borders or Russia".

He has a conspiracy theory that NATO - a political and military alliance which counts the US, UK, Canada and many countries in western Europe as members - was amassing strength against Russia and the only way to combat that problem was to attack America's vulnerabilities to ensure a "complete destruction of the enemy".

"Geologists believe that the Yellowstone supervolcano could explode at any moment. There are signs of growing activity there. Therefore it suffices to push the relatively small, for example the impact of the munition megaton class to initiate an eruption. The consequences will be catastrophic for the United States - a country just disappears," he said.

"Another vulnerable area of the United States from the geophysical point of view, is the San Andreas fault - 1300 kilometers between the Pacific and North American plates ... a detonation of a nuclear weapon there can trigger catastrophic events like a coast-scale tsunami which can completely destroy the infrastructure of the United States."

Full story

Comment And why not? (Score 4, Insightful) 227

Considering that nuclear power is the safest form of power the world has ever known, I'd say it's worthy of recognition for offsetting carbon more than anything else. To borrow a phrase, "It's the energy density, stupid."

There's a reason why China has 30 nuclear plants under construction, while the US just approved its first new plant in 30 years.

Comment Re: accounts (Score 1) 269

Ditto here. I forget what I had to do to verify, but it was basically the same as if I had called in and wanted to do something with my account. In fact, that's exactly what it was! At the end of entering the card into my iPhone, it prompted me to call the card's service phone number, where I verified my identity, and then they activated Apple Pay. This was in December, well before the rash of articles on this topic, so wasn't just a knee-jerk reaction by my bank.

True, it wasn't as much security as the bank wanted when I wired a down payment for my house; after receiving that fax, they asked no fewer than TEN security questions. I didn't know they had that many pieces of knowledge about me!

Comment Re: ECC Memory (Score 5, Interesting) 180

I hadn't heard of this either, but a quick google turned up a description of false parity RAM: http://en.wikipedia.org/wiki/R...
TLazy;DR: To save cost where parity RAM was required by the hardware but not by the operator, modules existed that would calculate the parity bit upon reading the RAM, rather than storing the parity bit. I don't see any evidence that this type of module ever existed for ECC though.

To make sure memory is ECC, it's probably sufficient to count the memory chips on a DIMM. If there are 9 or 18 (or even 36, if it's a particularly large DIMM) identically-marked chips, that's ECC. If there are 4, 8, 16, or 32 chips, then it's probably not. If one of the chips is marked differently than the others, it might be a little more complicated; it might be possible that it's a different memory chip (e.g. if there are 4 x16 memory chips, you'd only need one x8 to get a x72 ECC DIMM, so that last chip would be different). But it's also possible that it's buffered/registered memory, and the different chip is the buffer/register.

And an aside on the topic of buying RAM for yourself:
In general, I'm not a fan of cheaping out on memory. I did computer repair for a while, and it shocked me how many problems were caused by bad RAM - from the obvious ("my computer crashes every time I boot it") to less obvious ("every few days, an application crashes") to the rather insidious ("it was running fine, and now I can't mount my hard drive any more"). It got to the point where, when a computer came in with nonspecific symptoms like that, I'd open up the computer and peek at the RAM chips first. If they had no recognizable manufacturer, they were certainly garbage. If they were recognizable but not top-tier, they probably needed some stress testing on our RAM tester. And if they were the good stuff (Samsung always had my vote there, though it's hard to find because they don't sell directly to consumers), then it was probably something else.

That's also where I learned that things like memtest86 or other software diagnostic tools were basically useless too. Only the absolute worst memory would fail a test, even a looped test run for days. Most bad RAM was marginal - after all, it probably passed some manufacturing tests. We had a rather expensive (~$4k-8k) box that would test memory, doing things like varying the supply voltage or self-heating the RAM. When RAM is installed in your PC, you're still limited by the hardware - i.e. the voltage regulator and the memory controller - which probably keep the memory as close to nominal conditions as possible. Obviously, those machines are rather hard to come by, so you have to make do with software tests instead - but a pass on those just means I can't prove it's bad; it doesn't mean the memory is good. Even if I pass all memory testing, I'll still swap/remove/replace DIMMs in an attempt to find which one is bad, because it's often not obvious.

Comment Re:"Free" exercise (Score 1) 304

That description basically sounds like the San Francisco Bay area to me...

If you're interested in riding, find someone else who does it, and they may have helpful tips on where to ride. As you get more experienced, you might find yourself more comfortable sharing the road with cars - but certainly initially, most people prefer to take quiet residential streets or sidewalks. (Personally, I think sidewalks are a terrible idea for bikes - nobody is looking for you, and there are lots of driveways and obstacles. But if that's the only way that people feel safe riding, so be it.)

Comment Re:Changes based on the Season (Score 1) 304

I used to ride a hybrid in the snow with nearly-bald medium-width tires (28-32 or so, I moved narrower over several years). I usually avoided the 8-mile commute when it was actually snowing and cars were sliding around everywhere, though. Only fell twice on those skinny tires; both were when I tried to make ~90 turns at low speed. At higher speeds, the bike still wants to stay upright, even if there's no traction.

Layers are good, but nothing helps when the temperature is negative (F) and you start breathing hard when you go up a steep hill... I could feel my alveoli freezing with every breath. Never stopped me, though...

Comment Re:"Free" exercise (Score 1) 304

Yes. There's a group of people that rides from San Francisco to Google in Mountain View; roughly, it's 42.5 miles, though it's a bit different for each person, because most riders: 1. don't live at the coffee shop(s) where they meet up to start the ride, and 2. don't necessarily work at Google. Once they get to Google, smaller groups branch off in the directions of all the other area tech companies.

Just from hearsay, though; I've never ridden it myself (my commute is a bit tamer), though I've considered trying their route out for fun sometime.

In case the 42.5-mile ride is not to your liking, there are alternate scenic routes that go 48 or 62 miles, at a cost of more hills.

Comment Re:Facts not in evidence (Score 1) 406

Your (and my, and any individual citizen's) personal interpretation of the Constitution is not the measure. It is the interpretation and implementation by our three branches of government. I realize that some reading this believe they have all been compromised, or that they think some particular thing is "obviously unconstitutional" (even though the judicial, legislative, and executive branches say otherwise), but the fact is we have the system of government we have. So how about you consider the alternative: one where you don't assume that everyone working at every/any level of government, e.g., NSA, doesn't have the worst motivations and is actually trying to do their best to honorably, legally, and Constitutionally, protect our nation and its people instead of the opposite. How about that?

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