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Comment Responding to a below average AC post (Score 1) 109

Are modern coal plants really all that harmful to the environment?

Yes. Perhaps you've heard of climate change?

I thought they were able to capture the emissions at these big plants.

The cost of carbon capture for coal plants makes the operation far more expensive (per MWh and per MW) than nuclear or renewables. As a result, a tiny fraction of one percent of coal-fired generators in first world nations are capturing the carbon emissions and sequestering them.

As for your second paragraph -- it's one thing to be ignorant of a specific industry and its technologies and economics. That's your first paragraph, and that's fine. That's how we learn. But the ignorance exhibited in your second paragraph indicates a different kind of ignorance altogether. Please go back to the kiddie table.

Comment Re:Missing information... (Score 2) 393

If 40% of those university graduates are still overqualified by their mid-thirties, they've already been typecast by their experience in the 25-35 range.

That's certainly a problem with the data provided--it bundles together the fresh-out-of-school 25-year-olds with the decade-plus-in-the-workforce 34-year-olds. There's a lack of resolution. It could be that 40% of 25-year-olds and 40% of 34-year-olds are "overqualified". Or it could be that 60% in the 25-29 age group are overqualified, and just 20% of the 30-34 bracket.

Actually, that brings to mind another confounder to the interpretation of these data. As more young people get more years of formal education (3-year college diploma to 4- or 5-year bachelor's degree to 7-year bachelor-plus-master's degree) they enter the workforce later. A 25-year-old with a high school diploma might have been working for 7 years (and is also more likely to be working in a job for which they are not "overqualified" by their lower level of formal educational attainment). A 25-year-old with a master's degree might have graduated this summer and could still be job-hunting.

Comment Missing information... (Score 2) 393

... an increasing number of university graduates are overqualified for their jobs.... 40 per cent of university graduates aged 25-34 were overqualified for their job.... The problem is bigger than that, because those young workers spent money, time, and resources to get those qualifications.

It could be a problem, but we're missing some information. This is looking at people aged 25-34. A lot of them are taking crappy entry-level jobs. A lot of them don't have any significant work experience, and have trouble breaking into their preferred fields. A lot of them have student loans and other financial obligations, and just need to take a job - any job - to keep food on the table and a roof overhead. (That, in itself, is another kettle of problems that I'm not going to go into right now.)

An important question is, then, how many of them are still overqualified by the time they're into the 35-44 age bracket? Was the extra education actually "wasted", or did they eventually come out ahead because they didn't have to drop out of the workforce later on to go back to school to get the education they missed in their twenties? Did their extra "unnecessary" knowledge help them move up the ladder faster than they would have without it? (I'm not looking for anecdotes - of which I am sure there exist examples to suit any preferred narrative - but rather real data.)

And that leaves aside the rather more philosophical question of whether or not it's generally a Good Thing to have more university-educated individuals in it, even if they don't need those degrees specifically as job training. Are universities now only vocational schools, and only of value to society in that context? If I can't cash in my degree for a high-paying job, is it worthless?

Comment Re:amazing no ground scale or even strain gauges (Score 4, Informative) 366

...but then the stupidity of taking off at less than 100% throttle to save a little bit of fuel at the expense of increasing risk is also a pretty dumb thing to do, engineering wise.

Taking off at less than 100% throttle means reduced acceleration, which reduces stress on the airframe (and passengers). It reduces wear on the engines and - more important - reduces the risk of turbine failure. It makes the aircraft easier to control (less unbalanced thrust) if it does lose an engine immediately before or after takeoff.

So...not just to save fuel.

Comment Re:Turn key back on? (Score 1) 350

There is no diffraction...20,000 miles is nothing. A laser beam that measures several microns wide at it's origin will still be several microns wide at it's destination.

This is fundamentally incorrect. Even under ideal conditions laser beams will diverge in proportion to their wavelength and in inverse proportion to their narrowest diameter. Effectively, the laser light interferes with itself - diffracts - as it passes through the aperture from which it emerges. At visible or near-infrared wavelengths, a "collimated" 10-micron-wide beam will be more than 30 meters across at 1 km from its source. (I confess to doing the math in my head, but the order of magnitude is about right.) At 20,000 miles, the beam will be more than 100 km across. Wikipedia has the formulas if you'd like to play with them: beam divergence.

You can improve performance by increasing aperture (beam diameter) and wavelength, but there are limits. Beam divergence gets a hell of a lot better with a 1-centimeter (or 1-meter) rather than a 10-micron beam, but also puts about one millionth (or one ten-billionth) as much power down per unit of area on the target.

This isn't to say that space-based anti-satellite lasers aren't possible, but your assumptions about the behavior and performance of lasers over long ranges (and the associated technical challenges) are not grounded in adequate physics knowledge. The Soviets took a stab at launching an anti-satellite laser weapon back in 1987. Polyus weighed 80 tons, required a massive booster, used a 1-megawatt carbon dioxide laser, and was still only intended for low-orbit targets. (And suffered a launch failure, but that's not important.)

Comment Re:Hipsters fight over "free stuff" (Score 1) 554

What is interesting is that most EV drivers probably don't need the charge to get home and carry out their daily errands. If they do then they probably made the wrong vehicle choice. They just want to charge up on someone else's dime.

TFA actually addresses this very issue. There seems to be an assumed, implied pecking order. If you've got an all electric car that gets less than 100 miles/charge, you're at the top. Below that are gas-elec hybrids. Below that are the 250+ miles/charge Teslas.

I do think (as it seems you do) that making the folks pay for the charge would help sort this quickly. Tesla owners might be less inclined as they don't need it to get home, whereas folks with smaller battery packs might be willing to pay a premium. Etc.

Comment Re:An honest question (Score 4, Informative) 72

If I remember correctly, the noise floor of the previous instrument was approximately the level of the signal they were looking for. A better detector may help.

Indeed. It's hard to overstate the sensitivity of these instruments, or the vulnerability of these instruments to noise. To take one example, here's an ArXiv preprint that calculates that the original LIGO detectors would need to be physically shielded from tumbleweeds, since the the impact of a wind-borne tumbleweed on the building exterior (100 feet from the detector) could produce a vibrational or gravitational transient sufficient to appear to be a spurious gravitational wave signal.

Comment Needs more statistics (Score 4, Insightful) 181

Neither the summary nor the linked article provide the necessary statistics to tell us how well this algorithm actually works. We're told it has a 68% success rate, which presumably means that 68% of the time it gives the same answer as de Vries (the human subject/programmer).

The problem is, we're not told anything about the sensitivity or specificity of the technique. What is the rate of false positives? False negatives?

Let's say that de Vries typically finds 1 out of 3 (33%) of the profile pictures "attractive". His computer could score 67% accuracy just by rejecting every single picture. (Such an algorithm would have zero sensitivity, but perfect specificity, and a terrible false negative rate. The "reject-everything" algorithm also scores better the more picky de Vries gets.)

This sort of story is only interesting if it includes specific information about where and how his algorithm fails (and succeeds).

Comment Re: Stupid people are stupid (Score 2) 956

The only area of education not dominated by women in the past ten years is STEM, and men are also far behind women in biology & related sciences, and math, leaving really only computer science and the engineering fields, and physics to men.


Looking at the 2012/13 numbers, women do indeed significantly outnumber men as recipients of bachelor's and master's degrees. Women received about 1,052,000 bachelor's degrees to men's 787,000. (That's 57% to women.)

The source of that disparity - about 265,000 degrees - is interesting. About a quarter of the difference (a surplus of 61,000 degrees) is in education--principally teaching degrees. Another third (a surplus of over 84,000 degrees) are in nursing. Another quarter (another surplus of about 61,000 degrees) come from psychology. There's a good-sized surplus in social work and other social and community services (14,000), family and consumer sciences (18,000), and in visual and performing arts (21,000). That's about a quarter million degrees right there.

In other words, a lot of that surplus is 'job training'- or 'job certification'-type degrees, mostly in areas that are traditionally associated with soft, squishy notions of womanhood, and often in occupations associated with relatively lower salaries.

Comment Re:Why didn't his teacher stand up for him? (Score 3, Informative) 956

Presumably he made this for a class, and if so, why didn't that teacher stand up for him and tell them it was for his class?

And if it wasn't for a class or club or something, that does admittedly seem a bit suspicious.

He brought it to school to show the teacher in his engineering class, and then kept it out of sight in his bag. The alarm on the clock beeped during an English class later in the day, so he showed the project to his English teacher after class by way of explanation.

The only obviously wrong thing he did was (presumably inadvertently) let the alarm go off during a class. If he were a kid with a cell phone, the teacher would confiscate the phone for the rest of the class and possibly assign some other standard, trivial punishment. And that would be fine. Instead, we have a hopelessly irrational overreaction, almost certainly enhanced by the kid's race.

Comment Re:That was easy (Score 5, Insightful) 867

When you have an SSD that boots Linux in less than 20 seconds, who the hell *cares* if it doesn't hibernate correctly.

Presumably people working on multiple documents and/or in multiple applications who don't want to have to restart those applications, reopen their files, and rearrange their windows every time they go from home to office. (Or office to train. Or living room to desk. Or whatever.)

Comment Re:So then the question becomes (Score 1) 450

There's no persuasive evidence to indicate that Ashely Madison didn't fake female profiles. There IS evidence they faked profiles. Assuming they were only female seems a bit biased, no?

Note that your objection about fake profiles not chatting doesn't really hold up. Fake female profiles also don't chat. The idea is to keep presenting pictures and profiles that you like, to keep the hope alive.

I'm not sure if I'm being particularly unclear, or if you haven't looked at the original article and so are unfamiliar with the context for my remarks.

One of the flags that the analysis used to estimate relative proportions of "real" to "fake" accounts were a couple of data fields that were maintained in AM's private data but not accessible from the public-facing side of the site. These fields included information on when an account holder last checked his or her messages (if ever), when an account holder last used the AM chat system (if ever), and when an account account holder last replied to a message (if ever).

The number of male accounts which had carried out at least some of these activities at least once was on the same order as the total number of male accounts. (Of 30 million male accounts, about 20 million had checked their messages.) The number of female accounts which had carried out at least some of these activities was only a minuscule fraction of the total number of female accounts. (Of about 5 million female accounts, a few thousand had checked or sent messages.)

Do the data we have support the notion that fake females vastly outnumbered real females? Yep. It it possible that there were faked male profiles as well? Sure. Do the data we have support the notion that fake males make up any but a minority of male accounts? Nope.

Comment Re:So then the question becomes (Score 1) 450

There are reasons to fake male profiles. Having lots of male profiles with nice pictures and soothing, non psychopathic text helps with recruiting females and maybe getting them to stick around.

Sure, that's a hypothetical possibility.

In practice, though, there's nothing about the evidence at hand to suggest that that has happened. And you haven't presented a particularly persuasive case (or any case) to suggest why the fake male accounts would log in to read and reply to messages, where the female fake accounts would not. On its face, one would tend to expect the opposite behavior--AM would have benefitted directly (financially speaking) from encouraging the men to keep chatting with the fake women.

Comment Re:So then the question becomes (Score 3, Informative) 450

I suspect the truth is that whoever did the numbers in the OP article fudged them juuuust a bit.

For example, I see no references made to controlling for fake MALE profiles. Apparently only the female ones can be fake?

The analyses shown provided the data for both male and female profiles, which you would know if you had just read the article. The article also explicitly acknowledged that we don't know if the leaked data were manipulated or scrubbed in some way--of course, it's not like we're ever going to be given access to known-genuine data.

That said, there wasn't an obvious incentive for AM to fake male profiles. Unlike males, females were not charged to use the service. (Presumably because it *is* difficult to recruit women to these sites. It's not like we don't see offline parallels--there's a reason why bars have Ladies' Nights.) AM only made money when men contacted women. AM doesn't make money if real women send messages to fake men. Heck, it would cost them money, since those real women wouldn't be interacting with AM's paying male customers.

Be careful when a loop exits to the same place from side and bottom.