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Comment author: gwern 28 July 2014 06:21:12PM 1 point [-]

(It's A, right?)

investigate people's different intuitions of physics.

To some extent, 'folk physics' has already been studied a fair bit. For example, see the links at the end of http://lesswrong.com/lw/khd/confound_it_correlation_is_usually_not_causation/ about a quiz designed to measure how well people understand Newtonian mechanics and to what extent they succumb to incorrect folk physics beliefs.

Comment author: bramflakes 28 July 2014 06:41:04PM 0 points [-]

(It's A, right?)

If you do it in the Portal 2 engine (Portal 1 doesn't support moving portals) it seems to be A but with a slight push (google for videos).

The point is, I don't think the topology of the portals even allows for things like "conservation of momentum" to make sense (anyone can correct me here).

Comment author: bramflakes 27 July 2014 10:36:36PM *  3 points [-]

I'm always fascinated at the ginormous arguments that this picture is guaranteed to cause, and I wonder at what kind of experiments you could do with it to investigate people's different intuitions of physics.

Comment author: NancyLebovitz 27 July 2014 10:16:50AM 2 points [-]

If immigrants generally reduce utility for everyone in the country, would the same apply for the children of citizens?

Comment author: bramflakes 27 July 2014 11:55:17AM 1 point [-]

People intrinsically care about their children.

Comment author: Lumifer 17 July 2014 04:51:31PM 0 points [-]

How, precisely, is astrology an "extension of a good theory"?

There is a cute answer -- that movements of celestial bodies (e.g. the Sun and the Moon) certainly affect people's lives and fates.

And there is a historical answer -- that for centuries astronomy and astrology were, basically, inseparable.

Comment author: bramflakes 17 July 2014 05:11:20PM *  1 point [-]

The cute answer is actually more revealing than you think and might help resolve this conversation.

Astronomy lets you predict the way celestial objects move in the sky. You can trivially extend this to weak!Astrology, which just asserts that the movement of the celestial bodies has some kind of systematic causal impact on the way humans behave. However, you would quite reasonably take issue with strong!Astrology, which makes specific, detailed, wrong claims about the nature and extent of these interactions, as well as the general sloppy standards of the field of strong!Astrology.

Evolution lets you predict the way natural selection affects a population over time. You can trivially extend this to weak!Evpsych, which just asserts that evolution will have some impact in shaping the mental faculties of the population. But you can still disagree with some specific claims of evolutionary psychology, as well as the methodologies used to generate them, and the practices of the field as a whole.

I think that Benito thinks you're saying weak!Evpsych is wrong (that evolution didn't shape our minds at all), when you're actually just critiquing aspects of strong!Evpsych - e.g. that evolutionary psychologists are too quick to generalize from WEIRD college students into the rest of humanity, and so on. At least, my usual kneejerk response to critics of evpsych is "what, you think evolution stops above the neck?"

Comment author: Lumifer 17 July 2014 04:31:04PM 0 points [-]

a field purporting to be a science, that has journals and textbooks and experts

Just like astrology, then? :-) It's based on "an extension of good theory", too...

Whether something is a science is not decided by how many sciency-looking accoutrements and trappings it has.

Comment author: bramflakes 17 July 2014 04:39:55PM 0 points [-]

How, precisely, is astrology an "extension of a good theory"?

Comment author: gwern 14 July 2014 12:53:28AM *  2 points [-]

Boys only outperform girls at the very very top end,

I'm not sure I understand your link. If 43.7% of people score an A and that's the highest score, then it's definitely not 'very very top end' because that means it has almost zero information about anyone who is above-average (much less the extremes like 1 in 10k). And the Criticism section seems to accuse A-levels of a severe ceiling effect:

It has been suggested by The Department for Education that the high proportion of candidates who obtain grade A makes it difficult for universities to distinguish between the most able candidates.

Incidentally, notice the lowest grade: almost twice as many males as females.

Comment author: bramflakes 14 July 2014 11:38:19AM *  1 point [-]

I'm talking about Further Maths. The A grade for that is the only one with more boys than girls. It's much harder, and only 8,000 people take it compared to 60,000 for the standard Mathematics exam.

Then again, the ceiling still only looks to be the top 6-7% of the people taking math A-Levels. I think you're right.

Comment author: gwern 13 July 2014 05:11:52PM *  5 points [-]

It might, but there are subtleties you have to take into account. For example, ceiling effects will hide the claimed effect, and if there's not enough floor, can even produce a lower mean.

Imagine you have a test of 10 4-multiple-choice questions, male mean = female mean but males have higher variance, and the average student's score on the test would be 8, so lots of students score a perfect 10 but you would have to be retarded to score <=2. What will the mean by gender look like under this scenario? Since the male variance is higher, there will be several times more near-retarded boys than girls scoring in the lower ranks like 3-4; there will nearly as many normal boys as normal girls with normal scores like 7-9; and the rest will score 10 - but the many more boys than girls who are far out on the tail (are genius at maths) will also score 10 and look like fairly ordinary types. So the dim boys drag down the mean of all boys, the ordinary boys by definition match their girl counterparts, while the geniuses can't show their stuff and might as well have not been tested at all; and so on net, it looks like the boys perform worse than the girls even though they actually are the same on average and have a higher variance. This is because I invented a test which is able to pick up on the differences among the low-performers (by devoting 7 questions to them) but not among the high-performers (just 2 questions), and this favors the group with the least representation among both tails (females).

And most real-world exams are uninterested in making very fine gradations among the top 1% of students like you need to if you want to answer questions about 'how many female Fields Medalists - top mathematician in the entire world - should there be?' because with non-adaptive tests you would have to force the 99% of ordinary people to slog through endless reams of questions they have no idea about. (American schools have no incentive to look because they are not evaluated under No Child Left Behind based on how many world-class students pass through their halls, they're evaluated on the average student and especially the minorities.)

Other issues include to what extent those exams are based on class grades (the usual situation is boys do worse on grades, better on exams, because grades measure how much you can ingratiate yourself to your teacher by things like sitting still and doing even the most tedious moronic homework each and every time) and whether the exam are being administered after puberty where the increased variance is expected to manifest itself.

Comment author: bramflakes 14 July 2014 12:19:36AM *  0 points [-]

Thanks for the explanation. The skill ceiling/floor argument makes sense for GCSEs, but I'm not sure how well it works for A-Levels. Boys only outperform girls at the very very top end, and despite the complaints that the ceiling isn't high enough, I don't think it can account for all the discrepancy (he said, remembering his bad stats intuition).

Maybe it's higher male variance and higher female mean?

Class grades also count for zilch in both, it was all exams last time I checked.

Comment author: Vaniver 13 July 2014 01:50:45AM *  6 points [-]

The argument works just as well

I feel like the argument is slicing the problem up and presenting just the worst bits, when we need to consider the net effect on everything. This reminds me of a bioethics debate about testing error and base rate of rare lethal diseases: if five times as many people have disease A than disease B, but they look similar and the tests only offer 80% accuracy,* what should we do if the treatment for A cures those with A but kills those with B, and vice versa?

The 'shut up and multiply' answer is "don't give the tests, just treat everyone for A," as that spares the cost of the tests and 5/6ths of the population lives. But this is inequitable, since everyone with disease B dies. Another approach is to treat everyone for the disease that they test positive for- but now only 4/5ths of the population lives, and we had to pay for the tests! Is it really worth committing 3% of the population to the graveyard to be more equitable? If one focuses on the poor neglected patients with B, then perhaps, but if one considers patients without regard to group membership, definitely not.

*Obviously, the tests need to be dependent for 80% to be the maximal possible accuracy.

And people didn't notice the good blacks should be in the office and promote them at a higher rate to make up for it, either.

I don't know if it's possible to test this, and specifically it's not obvious to me that we need racial bias to explain this effect. That is, widespread cognitive stratification in the economic sphere is relatively new (it started taking off in a big way only around ~1950 in the US), and if promotions were generally inefficient, it's hard to determine how much additional inefficiency race caused.

These comparisons become even harder when there are actually underlying differences in distributions. For example, the difference in mean male and female mathematical ability isn't very large, but the overwhelming majority of Harvard math professors are male. One might make the case that this is sexism at work, but for people with extreme math talent, what matters much more than the difference in mean is the difference in standard deviation, which is significantly higher for men. If you take math test scores from high schoolers and use them as a measure of the population's underlying mathematical ability distribution and run the numbers, you predict basically the male-female split that Harvard has, which leaves nothing left for sexism to explain.

Comment author: bramflakes 13 July 2014 11:23:04AM 0 points [-]

Kind of offtopic but regarding male-female intelligence differences - in Britain at least, girls seem to consistently outperform boys in school math exams, which would imply there is a mean difference, in the opposite direction.

Comment author: Larks 12 July 2014 02:03:18AM 1 point [-]

Quick calibration test for those who like to have opinions on the US: of the standard US racial groupings (white, black, hispanic, asian) and the overall population, which do you expect to have the highest gini ratio for income? Why?

Here is the answer, according to the US Fed

Please use rot13 for spoilers.

Comment author: bramflakes 12 July 2014 01:03:44PM *  1 point [-]

Pbafvqrevat vzzvtengvba geraqf naq rlronyyvat jbeyq zncf bs tvav, V'q fnl Uvfcnavpf sbe gur sbyybjvat ernfbaf:

  • Gur oneevre gb ragel vf zhpu ybjre sbe Yngva Nzrevpn, fb vzzvtenagf jvyy or yrff fryrpgrq, fb gurl'yy cerfreir zber bs gur vardhnyvgl bs gurve ubzr pbhagevrf.

  • Yngvanzrevpna pbhagevrf arneyl nyy fpber uvture guna gur HFN.

  • Rhebcrna pbhagevrf arneyl nyy fpber ybjre (jvgu gur nffhzcgvba orvat gung juvgr Nzrevpnaf orunir zber-be-yrff fvzvyneyl gb gurve Byq Jbeyq pbhfvaf).

  • Gur gbc 5 zbfg pbzzba onpxtebhaqf bs Nfvna Nzrevpnaf ner Puvarfr, Vaqvna, Svyvcvab, Ivrganzrfr naq Xberna. Bs gubfr 5 pbhagevrf, bayl Puvan unf n uvture TVAV pbrssvpvrag guna gur HFN (ntnva jvgu gur nobir nffhzcgvba, naq gur nqqrq rssrpg bs fgebat fryrpgvba jvyy erqhpr inevngvba fgvyy shegure).

  • V qba'g xabj zhpu nobhg Nsevpna Nzrevpnaf, ohg V'q jntre gung zbfg ner pyhfgrerq nebhaq gur obggbz bs gur vapbzr qvfgevohgvba naq guhf unir n ybjre nzbhag bs jvguva-enpr vardhnyvgl.

  • "Uvfcnavp" nf n pngrtbel vf fbzrguvat bs n yrtny svpgvba - vg vapyhqrf crbcyr bs pbzcyrgr Fcnavfu naprfgel, zhynggbf, Nzrevaqvnaf, oynpx Nsevpnaf naq rira Nfvna vzzvtenagf. Sebz gung nybar V'q rkcrpg znffvir inevngvba va bhgpbzrf.


Well, that was a bit surprising.

Comment author: Mark_Friedenbach 11 July 2014 05:56:28PM 0 points [-]

Does it matter when in ~1 generation we will have the ability to redesign our bodies at will?

Eugenics is a 20th century concern.

Comment author: bramflakes 11 July 2014 06:43:56PM 1 point [-]

Where do you get the 1 generation estimate from?

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