Follow Slashdot blog updates by subscribing to our blog RSS feed

 



Forgot your password?
typodupeerror
×

Comment Re:Take back the seconds (Score 1) 383

RFK just wants to do an end run around reality. If you live in a utopia in which everyone's values are perfectly aligned, there are no negative externalities, and economic decisions are never necessary because there are no shortages and opportunity costs are always zero, then what he has to say is perfectly valid and interesting. We don't, though. Every one of those things he lists as a "bad thing" that GDP measures is just the result of an unavoidable economic decision. Take ambulances to "clear our roads of carnage". We drive cars. Sometimes they crash, and people are hurt or killed. This is avoidable, but only by eliminating cars. Eliminating cars would cause much more damage, though. So having cars and ambulances is more valuable than having no cars at all. (Having safer cars is also valuable. But safer cars cost more, and figuring out whether the safety is worth the cost is not obvious. RFK can't just decide for everyone.)

So I say to RFK: blah, blah, blah, sing a round of Kum-ba-ya.

Comment Re:Take back the seconds (Score 1) 383

The French have a higher standard of living than we do...

Where do you live, Spain?

If you're comparing France to the U.S., then the French standard of living is about 70% of the U.S. That's measured in "purchasing power parity", meaning (roughly) how many hours you have to work to buy a standard basket of goods.

Comment Re:My statistics (Score 2, Interesting) 575

FWIW, my stats over the past 6 months (plus 5 days of July):

        Jan     Feb     Mar     Apr     May     Jun     Jul (partial)
IE      82.2    80.7    79.6    77.2    78.1    77.3    75.3
Firefox 11.9    13.4    14.3    15.8    14.0    14.6    15.5
Safari   3.2     3.5     3.7     4.4     4.3     5.2     6.4
Others   2.7     2.4     2.4     2.6     3.6     2.9     2.8

The site is for a financial company and skews toward an older demographic.

Comment Re:Return on investment (Score 4, Interesting) 541

The system wouldn't just lose $760/year in value, it would also lose 2% in efficiency per year, which means that if he saved $3,000 the first year, he could expect to save only $2,940 the second, and so on (all else - electricity usage, cost of electricity, etc - being equal). The revenue stream then looks like this (over 10 years):

Year 0: Cost of $38400.

Year 1: Benefit of $3,000.

Year 2: Benefit of $2,940.

Year 3: Benefit of $2,880.

Year 4: Benefit of $2,820.

Year 5: Benefit of $2,760.

Year 6: Benefit of $2,700.

Year 7: Benefit of $2,640.

Year 8: Benefit of $2,580.

Year 9: Benefit of $2,520.

Year 10: Benefit of $2,460.

Value of system after 10 years: $30,400.

Plugging these numbers into the IRR formula gives you a 5.7% return per year.

If we make a slightly different assumption that the decreased output is geometric (not arithmetic) and still use the idea that the depreciated value equals the original cost times the current efficiency, then you can show that D + R = 7.9%, where D = depreciation rate and R = rate of return. So if you assume D = 2%, then R = 5.9%. But if D = 4%, then R = 3.9%, which is not great.

Doesn't sound to me like an obvious win for solar power. On the other hand, it's not an obvious money sink, either, so that's good. I'm sure things will continue to improve.

Would be interesting to see a subsidy-free comparison of both methods of electricity generation, but that's pretty hard. You can easily handle the consumer tax breaks, but how much do the producer's tax incentives affect the cost? And how much of his local coal/natural gas/hydro/nuclear generation is subsidized?

Comment Re:Single Best Fix: Introducing Discrete Mathemati (Score 1) 677

Er.. the "symbol manipulation rules", _are_ plug and chug.

I just got around to reading the whole 25-page PDF today, so I see the author of TFA is using a different meaning of "plug and chug" than I was. You see the importance of agreeing on definitions ahead of time.

If a student insisted on calling right angle "pigpens", I think I'd tolerate it for about 5 minutes unless he was the second coming of Ramanujan. :)

Comment Re:Single Best Fix: Introducing Discrete Mathemati (Score 1) 677

I don't dispute the premise that US math education sucks, or that it would be useful to add Discrete Math to the list. However, your assertion that all those courses are "just plug and chug" is just absurd. Geometry is generally centered around proofs - this is the first class most students ever have in which they are expected to learn a set of axioms and theorems, and construct new theorems from them. Trigonometry places some emphasis, at least, on trig identities, e.g. prove that tanx sinx = secx - cosx. Not extremely hard, but it's not just plugging numbers into formulas.

Calculus is similar: you work on limits, learning symbol manipulation rules like the chain rule and integration by parts, etc. Heck, even in algebra I you learn factoring polynomials, which is not at all plug and chug.

Again, don't get me wrong: I'm all in favor of more proofs and reasoning about math. But you're still mischaracterizing the rest of high-school math.

Comment Re:The notion of "Digital Rights" is ridiculous (Score 1) 151

While all you say is true, let's be generous and assume that the story poster really meant "information rights".

My own thought on that question is that if Nepal wants to put in a couple of clauses of information rights, great. But it seems to me that they have bigger fish to fry: get basic freedoms, separation of powers, checks and balances, etc. right. Otherwise your information rights are pretty much irrelevant.

Related thought: It ill serves a Constitution to be long or attempt to be complete. It should be general; it should be brief; and it should only grant powers (i.e. it should say things like "the government can only do X, Y and Z", rather than "the government can do anything except X, Y and Z"). It's quite possible information rights don't make this cut (I'm not trying to make that case, just pointing out that because something is good doesn't necessarily mean it should be in the Constitution).

Comment Re:Another one bites the dust (Score 1) 588

Not to mention available jobs (in the academy in particular) following graduation.

When I was an undergrad I knew a married couple both getting their PhDs at the same time. The wife had six job offers. The husband had zero (at the time; he might've had more later, after we lost contact). As far as I could tell they were about equally capable.

One anecdote does not a theory prove, but I'll bet this happens a lot.

Comment Re:deniers come out in 3 .. 2 .. 1 .. (Score 1) 658

The problem with this is that the Precautionary Principle as normally stated admits no cost/benefit analysis. If effect X causes a cost of Y, the PP would normally state that it should be mitigated if Y exceeds some threshold. But X might also have a benefit of Z which already mitigates Y, or even exceeds it.

I'm not suggesting that public policy be made on strict utilitarian principles, btw. Rather, each case is separate. Costs and benefits can't always be netted together. (Suppose a cost of $1 million brings the benefit of the avoidance of 1 death? Suppose the cost is $1 billion? Is the net cost/benefit positive or negative? We have no - and should have no - dollar/life conversion ratio than answers this question neatly.)

Here's an example of the PP gone awry: DDT. In developed nations, DDT is considered an environmental threat. It's known to build up in organisms higher up in the food chain, it's a human toxin, etc. And - importantly - the benefits from using it aren't all that great: we have other anti-mosquito toxins, and we don't have endemic malaria or other mosquito-borne illnesses anyway.

But there are African countries where this is not the case. The costs are still there, and they are grave. But the cost of not using DDT is arguably worse: they can't afford more expensive toxins, and they have serious disease problems. Hundreds of thousands of malaria deaths a year might be avoided through the use of DDT. I don't necessarily argue that it should be used - I'll leave that for another topic - but debate on the subject should not be curtailed by the PP. There should be debate on whether the environmental, and human, damage caused by DDT spraying is offset by the benefits of reduced disease.

One last little thing: I've read a couple of times that the alternative to expensive mitigation today might be "wiping out the entire human race". But come on, this isn't serious. Even in "The Day After Tomorrow" (which is obviously an implausibly disastrous, fictitious scenario) the equatorial regions were still livable. Is there any plausible scenario involving climate change where the entire human race is wiped out? This is the sort of hyperbole that hurts your side of this debate. If you want to use a bad scenario, use something plausible, like: Billions of people, mostly in developing countries, die from disease, starvation and rising sea levels. That's plenty bad enough, and at least it's possible.

Comment Re:deniers come out in 3 .. 2 .. 1 .. (Score 1) 658

However, stating that we need major CO2 emissions reduction is well within their competence. So they're stating that.

No, it isn't. It's within their competence to say that to reduce temperature by X degrees requires Y. That's doesn't mean we need Y, although they might think so. (And I'm eliding here a point about the degree to which they can draw even the direct relationship between X and Y - I don't think it's as exact as you seem to think.)

Same deal with virologists. Sure, we need them to tell us that we need X doses of flu vaccine to protect against the possibility of Y. But whether we think Y is a serious enough threat to be worth buying those X doses is not their call.

Comment Re:deniers come out in 3 .. 2 .. 1 .. (Score 0, Troll) 658

Let me clarify: almost all climate scientists think that we need major economic measures _yesterday_.

I don't think that's true, but even if it is, they're not in a position to make that call, are they? They're not economists, for one thing, and while they may be expert in climatology, they are not expert in macroeconomics. A climatologist can tell us, "If you want to avert X degrees of warming, you'll need to reduce CO2 emissions by Y." But - as experts - they cannot make the call of how much X degrees of warming is likely to cost, how much a reduction of CO2 emissions by Y is likely to cost, or what trade-off should be made between those extremes.

Finally, while climatologists have just the same vote that I do for making these trade-offs in a democratic society, they don't have more votes than I do. Ultimately, it's up to voters to decide where the trade-offs should lie. The alternative is basically global tyranny*, which I (for one) consider a cure worse than the disease.

* I'm not even being hyperbolic here. The scale of measures being proposed is massive and there would be a huge incentive to cheat. Therefore, the only way to enforce these measures would be to subjugate every nation to a global power capable of enforcement.

Slashdot Top Deals

This restaurant was advertising breakfast any time. So I ordered french toast in the renaissance. - Steven Wright, comedian

Working...