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Comment: Re:Some non-Knuth suggestions (Score 1) 247

by Stephan Schulz (#46837193) Attached to: Ask Slashdot: Books for a Comp Sci Graduate Student?
Sipser's book is not bad, but I find it much shallower than any of the editions of Hopcroft[,Motwani], Ullman. Many of his proofs seemed to be more hand-waving. On the other hand, he is somewhat good at building intuition, which is valuable for students not yet used to the domain.

Comment: Some non-Knuth suggestions (Score 4, Interesting) 247

by Stephan Schulz (#46836967) Attached to: Ask Slashdot: Books for a Comp Sci Graduate Student?

Comment: Re:Buy a Prius as your next car... (Score 2) 869

Bird deaths are no myth:

http://www.cfact.org/2013/03/1...

CFACT is not a remotely reliable source, nor to they cite any such source. Google Scholar is usually good at finding real research papers on the topic. This is the top hit for 2013, and while it finds some bird mortality due to wind turbines, it estimates the effect to be much lower than that of other anthropogenic risks for birds, even assuming a 10-fold increase in wind turbines.

There is no silver bullet, nor will we ever manage to return the planet to Garden of Eden conditions. But "there is no single perfect solution, therefore let's not do anything" is not a viable approach to life. Perfect solutions to any problem are exceedingly rare, but that does not stop us from improving situations.

Comment: Re:piotr (Score 3, Insightful) 330

by Stephan Schulz (#46321753) Attached to: Japanese Firm Proposes Microwave-Linked Solar Plant On the Moon

On ISS, they get about 0.1 mw from an acre, that is 24.7 mw from km2.

Pedantic remark: There is a slight difference between a mW (milliwatt) and a MW (megawatt), a factor of about a short billion, or 9 (decimal) orders of magnitude.

Even more pedantic: W is upper case (as it's named after James Watt). I'm not aware of any unit using a lower case "w" as the abbreviation. But in general, capitalisation is significant for units.

Comment: Re:Small problem (Score 3, Informative) 378

by Stephan Schulz (#46280847) Attached to: Darker Arctic Boosting Global Warming

Small problem with that is this summer had 50% less ice melt in the arctic

Says who? 50% less than what? 2012 was a record minimum year. 2013 has bounced back from that record low (in ice extend, not ice volume), but is still one of the years with the least sea ice extend science measurements began. And all the other similarly low extend years have been after 2005.

Comment: Re:Ha ha ha ha ha (Score 2) 410

by Stephan Schulz (#46265167) Attached to: Obama To Ask For $1 Billion Climate Change Fund

The real issue is that China has FORCED all of the manufacturing there. And they continue to build new coal plants weekly. It is for this reason why I continue to say that we need to tax ALL GOODS CONSUMED based on where they and their parts come from. If we do that, then it forces all nations to look long-term, rather than to do what China is doing.

China has forced manufacturing? E.g. by being cheaper and then letting the invisible hand do its thing? I'm not aware of China threatening war, or Chinese gangs going around smashing British-made teapots.

Yes, Chinese industrialisation causes massive ecological problems. But then, so did western industrialisation. You are proposing a tax based on where parts come from. Why that? And using what measures? For me, the reasonable approach is a Carbon tax (or import duty), not based on place of origin, but rather on amount of CO2 released in the production. Of course, that would also apply to fuels (or parts) locally consumed.

Comment: Re:Ha ha ha ha ha (Score 2) 410

by Stephan Schulz (#46263297) Attached to: Obama To Ask For $1 Billion Climate Change Fund

The developed world emits less than 40%, with just China emitting more than EUROPE AND AMERICA COMBINED.

For small values of "Europe and America" (i.e. the EU and the US, excluding e.g. Russia, Canada, Mexico and Brasil), barely, and with a much larger population.

The reason why China is increasing emissions and the developed world has slightly decreasing emissions is that they make all our stuff now. We're still driving those emissions by unlimited consumerism, it's just that we outsourced the dirty bits of actually making stuff. That's not good, of course. And it's still our problem - in fact, it would still be our problem if the Chinese were producing that CO2 for their own benefit only. It would just be harder to do anything about it.

Comment: Re: "Not Reproduclibe" (Score 3, Informative) 618

The proposed law does not say WHO reproduces it, merely that someone MUST be able to reproduce the results. If the EPA can point to another, independent, study which reproduces the results of the first study, it meets those qualifications.

Scientific studies often cost significant amounts of money to produce - at least, they cost significant amounts of researcher time. Unless a study is extremely controversial or you expect to get very different results, few scientists will spend the time. There is minimal new knowledge to be gained, most journals rarely publish papers on successful reproductions, and a CV that says "I did the same as Williams, the same as Jones, and the same as Mayer, and got the same results in each case" is not a career starter for a scientist, either.

Indeed, most studies that can be reproduced can be reproduced from the published papers. It's just hard work and expensive, which is why it's rarely done. Demanding reproducibility is fine, but demanding actual reproduction (as proof of reproducibility) would kill most science-based initiatives cold. Note, in particular, another law proposed by Lamar Smith that would allow NSF funding only for research that is "not duplicative of other research projects being funded by the Foundation or other Federal science agencies". Take the two together, and you have a requirement for reproduction, but deny funding to do the reproduction. Ooops - how convenient.

Comment: Re:But I heard (Score 1) 249

by Stephan Schulz (#45851115) Attached to: Reducing Climate Change Uncertainty By Figuring Out Clouds

D is quite far from certain....

"D" is the the claim that the increase in CO2 is anthropogenic. That is indeed known beyond even vaguely reasonable doubt - first, from simple accounting (we know fairly well how much CO2 we release) and secondly by isotope fingerprinting (the C we burn is from fossil fuels, which is depleted in 13C, and we can detect the resulting change in the atmosphere).

... For instance, take the end of the end of the Younger Dryas period. Rather than our current warming of 1C in 100 years, the end of the Younger Dryas period was marked by a warming of ~7C in 5 - 50 years.

The Younger Dryas was primarily an event in the Northern Atlantic region, and much less well-defined on a global scale. And we have good candidates for what caused it - primarily a slow-down of the thermohaline circulation as the result of the abrupt emptying of the large glacial lakes in North America.

Comment: Re:Models vs models (Score 1) 249

by Stephan Schulz (#45850859) Attached to: Reducing Climate Change Uncertainty By Figuring Out Clouds

The changes in air temperature measurements have diverged from the changes in atmospheric CO2 measurements. I was promised that was not possible - a violation of basic physics. I was lied to.

To bad if you listen to people talking nonsense. You certainly were not reading mainstream science. CO2 is not the only climate forcing, and there is plenty of natural and unnatural fluctuation gong on. However, the fact that some guys win at roulette does not change the fact that the house is winning on average. Indeed, even if someone busts the house, the gambling industry still makes a good buck.

Comment: Re:We're All Guily (Score 1) 1160

You don't, as a rule, steal a car if you expect to get five years in prison. However any semi-rational or career thief will do at least a basic intuitive probability analysis: say the probability of getting caught is 5%, then the "expected " jail time is only 3 months, which may be a much more reasonable price to pay for the available profit, especially for a risk-prone personality.

...which again confirms what studies show: deterrence is not primarily based on draconian punishment, but on a high rate of solved crimes.

I like your signature ;-).

Comment: Re:We're All Guily (Score 1) 1160

It doesn't. The justice system has nothing to do with us being "better" than anyone else, it exists to (1) interrupt the cycle of reprisals that "code of honor" systems create("An eye for an eye leaves the whole world blind"), by delegating judgement and punishment to a third party held blameless for actions committed in the line of duty. (2) discourage future crime through a combination of making an example of criminals caught to dissuade others [...]

(1) requires that the punishments inflicted be sufficient to prevent the wronged individuals from taking justice into their own hands. Obviously if the crime is particularly heinous or the wronged often inclined to violence that may set the bar rather high. (2) requires that punishments be sufficiently unpleasant that people who believe they probably won't get caught still don't think it's worth the risk.

Of course, nearly all even semi-civilised countries manage (1) to a very high degree without the death penalty. And (2) has been shown to be spurious over and over again. Criminals don't, as a rule, expect to be caught. If you assume that you are caught, even a moderate prison sentence would be enough to dissuade most crimes. Who would steal a car if he expects 5 years in prison in return?

FORTUNE'S FUN FACTS TO KNOW AND TELL: A guinea pig is not from Guinea but a rodent from South America.

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