Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 



Forgot your password?
typodupeerror

Comment Carbon dating (Score 2) 155

I feel obliged to point out that isotopic fractionation is not "central" to carbon dating. The key to carbon dating is that radioactive carbon-14 decays to nitrogen-14 with a half life of roughly 5700 years, enabling biological material to be dated by its residual carbon-14 content. That is not isotopic fractionation, it's radioactive decay. Isotopic fractionation would be involved if you observed a difference in the ratio of carbon-12 to carbon-13 in plants versus that same ratio in the air.

Comment Re:Because Mars is the best chance for the price (Score 1) 298

Dead on. It's not like you can just look at a pile of dirt (or ice) and tell whether there's something living in it. And you certainly can't do life detection from orbit unless you have a serious biosphere going, which obviously none of these outer solar system moons have. And the Europa drilling ideas that people like to throw around aren't going to be technically feasible in the time frame of the missions to Mars -- if ever.

Comment Doesn't help grade inflation (Score 2) 323

I'm not arguing that this is a good or bad idea, but it won't do anything to change grade inflation. In my experience (as a TA for a number of different classes), college professors look at the point totals at the end of the semester and determine the letter grade cutoffs by hand so that they have the grade distribution they want. I'm not saying they're going through and making sure specific students get a particular grade, just that they want, say 50% A's 30% B's and 20% C's and they'll put the cutoffs where they need to be for that to happen. Just because the essays are graded tougher doesn't mean they can't still give half the class an A.

Comment Re:Associative memory (Score 1) 60

Exactly! What this study ignores, consciously I'm sure, is the affective domain. They basically ask, "which of these image that you don't care about at all do you remember?" They don't ask, "which picture from you vacation is your favorite?"

I think using the word "memorable" is slightly misleading for this reason, because memorable has a connotation that is much broader than merely "remembered". It implies that there is an emotional connection to something.

Submission + - Problems with Truncation on the Common Application (nytimes.com)

jaroslav writes: A combination of rigid caps on space and poor documentation of the space limits is adding stress on students applying for college using the Common Application, the New York Times reports. The story explains that the application lists word limits for questions, but actually enforces space limits. As a result, an answer with wide characters, such as 'w' or 'm', may run over space even without reaching the stated word limit. It is not explained why an electronic submission must have such strictly enforced limits.

Comment Good luck ... (Score 2, Insightful) 360

I wish the people and governments of these island countries well and I certainly think they should try whatever they can to get attention for their plight, but the lesson learned in COP15 is that the major industrial powers of the world are not willing to make major changes in their greenhouse gas emissions. And basically the rest of the world can't do a damn thing to make them.

Slashdot Top Deals

I'm a Lisp variable -- bind me!

Working...