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Comment Re:Lies, damned lies, and statistics (Score 1) 182

Every physics book I've read that has mentioned gravitons has noted that they haven't been shown to exist. They're predicted, and some of their properties (should they exist) are known, but that's true of other things too.

What astronomers and physicists have managed to do about "dark matter" is to find where it is and some things it isn't, last I looked. Some physicists thought the WIMP hypothesis likely (weakly interacting massive particle), but AFAIK the preliminary experimental results haven't been promising.

Comment Re:Why would anyone be shocked? (Score 1) 182

Don't microeconomic demand curves measure utility? If I might or might not spend $100 on a widget, the widget has very approximately the same utility to me as $100. They aren't a great measure, since it's hard to figure out what a demand curve is.

We have observed minimum wage changes in the past, and their effects, so there's some guidance. One source thought it likely that a raise in the US to $15/hour would slightly reduce employment, would mean the lowest quintile would get more purchasing power, and the top one would get less purchasing power. (I don't remember where I got that one.) We aren't going to know for sure (and even if we do it, it will be in unique economic circumstances with confounding factors, like every other time, and we won't get a clear and precise result), but we can have an idea.

Comment Re:Why would anyone be shocked? (Score 1) 182

I was contracting at GMAC-RFC (the home mortgage arm of General Motors) when the crash started.

I was working on software models to predict what would happen with low-quality mortgages. There was certainly an effort to figure out which mortgages were likely to be bad and which weren't. I didn't do the verification, but it looked good to the people that did (in a statistical way; all we could do was figure out probabilities). Personally, I wondered why there were any mortgages with "stated income" and "stated assets", in which the mortgage company didn't verify income and assets - liar's loans, as they were called.

Another issue was that real estate prices stopped going up. The bad mortgages were often sold to naive buyers with the assurance that, if the borrowers couldn't manage to pay the mortgage, they could always sell the house for enough to pay off the mortgage plus a little. As long as this was true, nobody would really lose that much. The bank would wind up with someone paying a mortgage, and the home buyers would wind up with some of their investment back, as well as having been able to live in a house. When they peaked and then declined, it left a lot of people with a mortgage larger than the market value of the house ("underwater"), and when they couldn't pay the mortgage everybody suffered. Another thing I wondered about was why, in the model, there were parameters for how fast housing values would increase, but they didn't go negative.

Comment Re:Real World? (Score 1) 120

Unfortunately, since I haven't seen the movie, I was talking about the book. It's probably more accurate, but it is disappointing when a hard SF book starts off totally fudging something. I'll probably see the movie Sunday.

I swap tweets from time with a guy whose signature line was "There is a robot on Mars. I give it instructions, and it does what I tell it to do."


Comment Re:And why should this be done? (Score 1) 660

To be anecdotal, my son strongly resembles me in personality and talents. He has a remarkable ability for mathematics, like me. We did not push him in any way towards that, or give him extra teaching beyond having a copy of Number Munchers. He went into college intending to be a mechanical or electrical engineer, and took a programming for engineers class in his first semester. He immediately changed his major to Computer Science, and has stuck with it since. Again, we did not push him in any way, except for me answering some general questions when he was dabbling in Lua scripting in an on-line game. If it was a matter of wanting to grow up like Dad, he'd have been programming earlier.

The resemblance is so great that, if you gave me lab DNA results saying he wasn't my son, I'd figure the lab screwed up.

Comment Re:Deconstructing diversity in tech (Score 1) 660

Your assumption that my assumption (which isn't really an assumption) is erroneous is unsupported and, I believe, wrong.

First, this isn't an assumption. It seems to me a very likely circumstance. In general, when we see women or men or minorities rare in a field, we often find that there are social pressures involved. If a girl announces in school that she wants to be a hairdresser when she grows up, no real problem. If a boy does, there is going to be a big problem with his peers. That's social inhibition.

Gender roles have changed considerably over history. If it turns out that our society has actually gotten them right biologically, without explicitly researching and testing, that would be a near-miracle.

Comment Re:100% BULLSHIT (Score 1) 365

but the laws of our universe completely preclude the possibility of wind power ever being a useful, practical, economic contributor to large national grids; EVER

This is a very strong statement. Certainly it depends heavily on things like the cost of turbines and the cost of producing electricity by other means (likely to go up). It already seems to have a place in Germany, although their cost of power appears to be considerably higher than ours.

Comment Re:Show us the data (Score 2, Informative) 365

Well, but then you have to add the cost of the gas power plant to the cost of the wind power plant in order to calculate the actual cost of wind power.

Assuming you're a utility electricity producer, you need to have the gas plant anyway, as a supplement for your base load. Then you think about adding the wind plant, which is extra expense but produces electricity much less expensively. If the cost of the wind plant is less than what you expect to save by not running the natural gas plant, the turbines are a good deal.

Similarly, batteries are valuable in any power system as a way of smoothing peaks and valleys. If you've got them, you can increase your baseload power and use the batteries to even that out, saving the more expensive gas. The batteries are more useful with wind power, but the utility would get them even without wind.

A freelance is one who gets paid by the word -- per piece or perhaps. -- Robert Benchley