How Can There Still Be a Sex Difference, Even When There Is No Sex Difference? • Hacker News Board

Re: How Can There Still Be a Sex Difference, Even When There Is No Sex Difference?

#271

Post by dragonwriter » Tue, Jul 07, 2015, 9:02 PM UTC

MichaelCrawford wrote: post #269

TheOtherHobbes wrote: post #59

Earlier quoted context omitted.

I suspect this is not unusual. I was asked to be a sperm donor at a party by a lesbian couple I'd never met before. They were completely serious, but the catch was no contact with the child. The problem with arguments from reproductive psychology is that we know very little about reproductive psychology in history. So modern ideas about female partner choice shaping genetics aren't necessarily a given. It's not unlik…

There are other traits than IQ which promote the success of the species. Even if unintelligent, physical strength and endurance enable one to hunt, to flee from predators. Sharp eyesight and sensitive hearing. Those of African heritage commonly have Sickle Cell Anemia. While it is a crippling illness it gives one resistance to malaria; in much of Africa that enables one to live longer than those with healthy blood ce…

> Those of African heritage commonly have Sickle Cell Anemia. While it is a crippling illness it gives one resistance to malaria; in much of Africa that enables one to live longer than those with healthy blood cells.

That's not quite right. Being heterozygous for the sickle-cell trait produces reduced symptoms from malaria (but not immunity), while being homozygous for the trait produces sickle cell disease and and, consequently, greater vulnerability to malaria (since malarial infection, in addition to its other effects, frequently produces sickle cell crises in persons with sickle cell disease.)

Re: How Can There Still Be a Sex Difference, Even When There Is No Sex Difference?

#272

Post by MichaelCrawford » Tue, Jul 07, 2015, 9:05 PM UTC

JoeAltmaier wrote: post #270

MichaelCrawford wrote: post #269

Earlier quoted context omitted.

There are other traits than IQ which promote the success of the species. Even if unintelligent, physical strength and endurance enable one to hunt, to flee from predators. Sharp eyesight and sensitive hearing. Those of African heritage commonly have Sickle Cell Anemia. While it is a crippling illness it gives one resistance to malaria; in much of Africa that enables one to live longer than those with healthy blood ce…

...or red hair, or blue eyes, which spread simply because they were so darn cute. They're only like 12,000 years old!

A recent study found that those with blue eyes are predisposed to alcoholism. Doubtlessly that will lead to employment discrimination against those with brown eyes, as management types like to party.

I once read that every human society that had agriculture also had beer. We have had agriculture for roughly 12,000 years.

Re: How Can There Still Be a Sex Difference, Even When There Is No Sex Difference?

#273

Post by diamondback » Tue, Jul 07, 2015, 9:07 PM UTC

yedava wrote: post #260

kefka wrote: post #199

Earlier quoted context omitted.

Not particularly surprising. Feminists in a general sense are usually pretty bad people. They espouse their gender over masculine and other genders. It is akin to saying that the Black Panthers are good, when the KKK is bad. They're both bad. Feminism == Masculinism == sex discrimination

What an ignorant comment. Feminism is directly responsible for women getting their rights, like abortion. Saying it is "just as bad as..." is a clueless claim. What wrongs has Masculinism ever corrected?

'Masculinism' has corrected almost all wrongs since time immemorial. It has caused many of the too.

Re: How Can There Still Be a Sex Difference, Even When There Is No Sex Difference?

#274

Post by convivialdingo » Tue, Jul 07, 2015, 10:31 PM UTC

mikeash wrote: post #265

convivialdingo wrote: post #263

Earlier quoted context omitted.

"Academics have approximately zero power." Sure, academic don't rove about with black helicopters and guns, but academia has the ear of industry, politics and government for good reason. Applied academics has the ability to predict outcomes, grow economies, win wars and generate massive revenues. But it also has the ability to go horribly wrong. It's undeniable that Nazi eugenicists modeled their ideology after the A…

Some academics have the ear of powerful people. Some don't. Like in any other field. Academia tends to be where far-out ideas come from, just because it's an environment that encourages it. Some of those ideas will be discovered by people in power and used to shape policy. Other will not. To blame academia for this or point to this process as evidence that academics are powerful seems an awful lot like being afraid o…

I agree. Language is just a form of communication, it can be used or misused.

It would be a fiction to downplay the power of academics in modern society. Academics has the power to mold and frame the minds of the next generation of leaders, alter government policy and to influence an entire populace from childhood.

I see your point that academics has been demonized at times, however I think it's more appropriate to judge it on outcomes.

Re: How Can There Still Be a Sex Difference, Even When There Is No Sex Difference?

#275

Post by ksrm » Tue, Jul 07, 2015, 10:55 PM UTC

rndn wrote: post #26

The next article in this series on "Which sex is playing higher stakes reproductive game?" is also worth reading: http://www.psychologytoday.com/blog/the-how-and-why-sex-diff... It reminds me of an interesting hypothesis I've read about the other day that the concept marriage plays a significant role in the success of our culture as it counteracts this difference. It allows more men to reach a social status at which…

> So we are possibly actively destroying a pillar of our culture as we are devaluing marriage.

And how are we doing that exactly?

Re: How Can There Still Be a Sex Difference, Even When There Is No Sex Difference?

#276

Post by dlss » Tue, Jul 07, 2015, 11:01 PM UTC

logfromblammo wrote: post #264

dlss wrote: post #222

Earlier quoted context omitted.

This also isn't how statistics works. > We can further assume, arbitrarily, that P(B) = 0.02 (one in every fifty people make good engineers). So the likelihood that a person is a good engineer given that they are female is P(B|A). > P(B|A) = 0.4 * 0.02 / 0.5 = 0.016 > P(B|~A) = 0.6 * 0.02 / 0.5 = 0.024 > What we learn from this is that sex is not a good screening criterion for finding good engineers. You realize an a…

Your post looks like a non-sequitur to me. But for the sake of math... For an arbitrary variance multiplier of 10 (std. dev. sqrt(10)), there are no non-imaginary solutions for a high-pass threshold where you can achieve a 60:40 split between two populations that have the same median. You can get about a 58:42 split, putting your threshold a bit below the common median. But to achieve a 60:40 split, you need one popu…

I'm super confused by this reply. The article says that the stddev of the distribution of male IQ is larger than the stddev of the distribution for female IQ, and also seems to state the mean and median are equal. GGP threw out 60/40 as their believed split of men to women being good engineers. I took this to mean that GGP was saying he believed engineering talent to be independent of gender when IQ was present, and that engineering required a higher than average IQ. More formally:

  P(good engineer | IQ) * P(IQ | gender) == P(good engineer | gender)

In that model the 60/40 split comes from a conditional distribution of gender given an IQ above some threshold. So something like:

  julia> women = sum([randn() > 1 for i=1:10_000_000])
  julia> men = sum([(randn() * 2) > 1 for i=1:10_000_000])
  julia> women / (women + men)
  0.3395449535000696

Which isn't exactly 60/40, but is fairly close. It says that [iff the 60/40 split is true], the stddev difference needed is less than 2x.

If you prefer exact math, the ratio above is

  erfc(1/sqrt(2)) / (erfc(1 / (2 * sqrt(2))) + erfc(1 / sqrt(2))) =~ 0.339593

and the exact solution for a 60/40 split is

  1 / (sqrt(2) * inverseerfc((3/2) * erfc(1/sqrt(2)))) =~ 1.4

Though FWIW I find the simulation version more intuitive (likely because of a misspent youth programming rather than a misspent youth mathing :p).

Can you explain the model you were using to motivate the mean vs median calculation? I feel like I'm missing something interesting.

Re: How Can There Still Be a Sex Difference, Even When There Is No Sex Difference?

#277

Post by ksrm » Tue, Jul 07, 2015, 11:27 PM UTC

logfromblammo wrote: post #178

golemotron wrote: post #121

Earlier quoted context omitted.

Actually, no. When you pick out an individual there's still a 60% chance than one is better than the other given no other information than their sex. That's how statistics works. But I agree that it's better not to make the prejudgement at all. The problem is that there are many things that are true in the aggregate but we can't acknowledge them because we are scared of demotivating people. Is that the best we can do…

That is not how statistics works. This is how you reverse a conditional probability (Bayes's Rule): P(B|A) = P(A|B) * P(B) / P(A) If A is "female" and ~A is "male", and B is "good engineer", then what we know , including ancestor post's assumption, is this: P(A|B) = 0.4 (the population of known-good engineers is 40% female) P(A) = 0.5 (the population as a whole is 50% female) We can further assume, arbitrarily, that…

I don't understand why you are taking the advantage between the two options to be the difference between their probabilities, rather than the ratio. If I am 2% successful at X and you are only 1% successful, I am 0.02/0.01 = twice as successful as you, not 0.02-0.01 = 1% more successful.

As dlss has explained, it doesn't matter what constant you multiply by, the ratio is the same.

Re: How Can There Still Be a Sex Difference, Even When There Is No Sex Difference?

#278

Post by erikpukinskis » Tue, Jul 07, 2015, 11:52 PM UTC

golemotron wrote: post #36

I'm surprised to see this ranking so high on HN. Sex-based difference is the biggest taboo of our time. The current educational and political system is organized toward exclusively presenting the view that gender is a cultural construct and there are no differences between men and women other than plumbing. Men and women, on average, differ significantly on career choice, likes, dislikes, and motivation. And, it has…

I was with you until here:

"it has nothing to do with whether they were giving dolls or cars as toddlers"

Either you're being hyperbolic in which case I can't really parse your comment because I don't know which points you're serious about, or you actually believe that there is no relationship between the specific toys children play with and their development, which ignores a massive body of reasonably well conducted research in developmental psychology.

Re: How Can There Still Be a Sex Difference, Even When There Is No Sex Difference?

#279

Post by rndn » Wed, Jul 08, 2015, 12:13 AM UTC

ksrm wrote: post #275

rndn wrote: post #26

The next article in this series on "Which sex is playing higher stakes reproductive game?" is also worth reading: http://www.psychologytoday.com/blog/the-how-and-why-sex-diff... It reminds me of an interesting hypothesis I've read about the other day that the concept marriage plays a significant role in the success of our culture as it counteracts this difference. It allows more men to reach a social status at which…

> So we are possibly actively destroying a pillar of our culture as we are devaluing marriage. And how are we doing that exactly?

For example in the course of people saying that marriage limits their freedom, that the years of fun are over after it etc. Especially in progressive circles it seems to be frowned upon and it's regarded as boring and unprogressive if people marry early. It's probably also losing value as people become more secular and the concept isn't tied to their world views as tightly anymore.

On a more general note, I have the feeling that we are losing other useful cultural mechanisms over the course of secularization as well, and we are right at the transition where both spiritual and scientific explanations are regarded as unacceptable. I'm however still hopeful that the work by philosophers like Sam Harris and Daniel Dennett can help us building a value system based on naturalism.

Re: How Can There Still Be a Sex Difference, Even When There Is No Sex Difference?

#280

Post by geomark » Wed, Jul 08, 2015, 1:04 AM UTC

chi-sq wrote: post #210

nailer wrote: post #87

Earlier quoted context omitted.

Check out the work by Simon Baron Cohen at Cambridge, which includes studies on newborns showing clear differences between genders. http://www.math.kth.se/matstat/gru/godis/sex.pdf Also check out the work of John Money, who popularised the concept of 'gender as a social construct', and wrecked the life of a young man whose penis had been destroyed by trying to raise him as a girl: https://en.wikipedia.org/wiki/David_…

(currently finishing Masters in Methodology/Statistics in Psychology) There is evidence of inter-sex differences (and in many areas girls are at advantage), but the provably innate part is small, and the intra-group variance coming from other factors (that may include elements of culture) is much bigger. This allows for conclusions on population, not individual level. On a related note, affirmative action programs se…

Yes, I understand that the means may differ significantly but the variances are fairly large so there is lots of overlap between sexes, just as the article linked by OP discusses. Although, there are many characteristics and they all aren't going to exhibit the same spreads. I wonder if some have significantly smaller variances. The characteristic I keep noticing is how rough young boys are when they play compared to young girls. My small sample shows a very tight variance; young girls are much softer in their play compared to boys. Is that cultural conditioning at such a young age?