"Race doesn't exist," and the myth is drowning blacks

[ApostateAbe]

In retrospect.

This value is useless as you present it. Aside from the difference in average density being only 0.01 g/ml <snip>

You say that as though 0.01 is a small number. In the first place, that's 10 g/l, which is to say, 2 lbs per 200 lb man. Is anybody here willing to jump out of a boat in the middle of a lake and swim to shore, and then do it again with 2 lbs of metal in his pockets, and report to us that the extra weight didn't make it much harder?

And in the second place, a swimmer is buoyed up by the force of gravity on the mass of the displaced water, to the tune of 1 g/ml. So the ratio of the net downward forces the respective swimmers need to counteract by muscle power is not 1.065 / 1.075, i.e., the 1% difference it looks like. The ratio is 0.065 / 0.075, i.e., a 15% difference. That having to work 15% harder to stay afloat wouldn't significantly affect drowning rates is, how shall I put this, blindingly non-obvious.

The two-pound weight in the pockets--that is a good way to phrase the argument. Most free-weight rooms at gyms have 2.5-lb weights, to get a rough idea of it. It is a small weight in most everyday contexts, but not in the context of trying to stay afloat, and, yeah, imagining that every black man was like a white man with an extra two-pound weight in his pockets (proportionally reduced for children and so on) seems to do a lot to explain the differences in drowning rates between whites and blacks. The lung-size disadvantage would likewise add to the racial drowning difference for sure, though there is still a question of how much.

 

[ApostateAbe]

I found the standard deviation of body densities: 0.012 for whites and 0.015 for blacks. So, the racial difference in body densities is about 0.8 standard deviations.

 

[ApostateAbe]

Here are some calculations building on the standard deviations and Bomb#20's argument.

200 lb is not the average weight, so let's be fair. The average weight of a young man with the given densities is about 80 kg or 175 lbs.

For an 80 kg black man, his volume is:
80 kg/(1.075 g/mL)= 74.4 L

For an 80 kg white man, his volume is:
80 kg/(1.065 g/mL)= 75.1 L

It is a difference of 0.7 L, or 0.7 L*(1.07 g/mL) = 750 g = 1.65 lb of extra buoyancy force for whites than for blacks.

So, the average black man in a swimming pool is like the average white man but with a very dense 1.65 lb weight in his pockets. Doesn't seem like so much, but a little extra weight can count for a lot when trying to stay afloat.

The inequality is greater at the right tails of the overlapping normal distributions. I found the standard deviation of body densities in this study. It is 0.012 g/mL for whites and 0.015 for blacks. The two distributions have different means and different standard deviations, so the calculations are a test of my ability to think straight, but I will give it a shot.

Given a racial density difference of 0.01 g/mL, this means the average body densities of whites and blacks are about 0.83 white standard deviations apart and about 0.66 black standard deviations apart.

Using a z-score calculator, assuming an extra weight of 1.65 lb, with z=0.66 black standard deviations, Q is 0.25, and it means that 75% of blacks are like the average white but with at least an extra 1.65 lb weight in their pockets. With z=0.83 white standard deviations, Q is 0.20, so only 20% of whites are like the average white with at least an extra 1.65 lb weight in their pockets.

What if it is a body density equal to an extra 5-pound weight in their pockets? For whites, this is 5 lb*(0.83 SD/1.65 lb)= 2.52 standard deviations above the white mean. This means Q is 0.005868 or 1 in 170. One in 170 whites have a body density equal to an extra 5-pound weight in their pockets. But, for blacks, this is 5 lb*(0.66 SD/1.65 lb)= 2 black standard deviations above the white mean and equal to 2 minus 0.66 black standard deviations = 1.33 black standard deviations above the black mean. Another way to calculate this is that 5 pounds of extra weight for the average white is just 5-1.65=3.35 pounds of extra weight for the average black, and 3.35 lb*(0.66 bSD/1.65 lb) = 1.34 black standard deviations above the black mean. For z=1.34, this means Q is 0.090123 or 1 in 11. One in 11 black men is like the average white man but with an extra five-pound weight in his pockets, or 15 times as many blacks as whites.

 

[Juma]

&quot;Race doesn't exist,&quot; and the myth is drowning blacks

I found the standard deviation of body densities: 0.012 for whites and 0.015 for blacks. So, the racial difference in body densities is about 0.8 standard deviations.

What criteria did you use for "whites" and "blacks"?
Who provides these figures? Based on what?


But then these numbers are uselless anyway since drugs and ability to swim is a much greater factor...

 

[ApostateAbe]

I found the standard deviation of body densities: 0.012 for whites and 0.015 for blacks. So, the racial difference in body densities is about 0.8 standard deviations.

What criteria did you use for "whites" and "blacks"?
Who provides these figures? Based on what?


But then these numbers are uselless anyway since drugs and ability to swim is a much greater factor...

The relevant racial weights, body density averages and standard deviations come from this study:

http://www.jstor.org/stable/41463983?seq=3#page_scan_tab_contents

I presume they relied on self-identification.

"But then these numbers are uselless anyway since drugs and ability to swim is a much greater factor."

It is now looking as though the body-density explanation has strong predictive power, and I think the habit of blaming black problems on drug abuse or whatever needs to take a back seat in this case.

 

[ApostateAbe]

So, how can this information be useful? Spot the drowning child.

Full story at The Daily Mail.

 

[exodiasrightleg]

Encouraging black people to swim is useless, so... what's YOUR solution, Abe? Segregate them away from pools and beaches? Funny how the endgame of Human Genetic Diversity is always "black people shouldn't be doing X anyway".

 

[exodiasrightleg]

Also, wow that story. You're an order of magnitude dumber than I thought. The lifeguard saw the child's tube being turned over by a wave, which as far as I know is not a situation that favors whites or blacks. What would an ApostateAbe approved lifeguard do in this situation? Probably letting a white child die on her watch because she's either too busy scanning the pool just for black people, or too slow on the rescue because hey, white people are more buoyant right?

 

[ApostateAbe]

Encouraging black people to swim is useless, so... what's YOUR solution, Abe? Segregate them away from pools and beaches? Funny how the endgame of Human Genetic Diversity is always "black people shouldn't be doing X anyway".

Encouraging black people to swim is not just useless. It is dangerous. It is useful for those who want fewer blacks in the world, though of course that is never the intent. But, I would not go as far as to ban blacks from swimming. Body densities fall along a normal distribution, and some blacks are to the right of the peak (they will drown lacking exceptional swimming ability) and others are to the left (they will float naturally with a breath of air). The solution is knowledge. No more delusions. Some blacks are either at the left tail end of the body density/lung size distributions or they beat the odds and can swim just fine. They should not be prevented. But blacks who fear swimming should not be ridiculed and should not be pushed into the pool. They are acting in their own probable best interests. We should not assume that blacks are just like whites and they can learn to swim just as easy as whites. Urban leaders know that blacks (1) generally don't swim and (2) are more likely to drown. They think #1 causes #2. So, they push blacks in the pool. "Whites can swim, so why can't you?" This needs to stop.

 

[ApostateAbe]

Also, wow that story. You're an order of magnitude dumber than I thought. The lifeguard saw the child's tube being turned over by a wave, which as far as I know is not a situation that favors whites or blacks. What would an ApostateAbe approved lifeguard do in this situation? Probably letting a white child die on her watch because she's either too busy scanning the pool just for black people, or too slow on the rescue because hey, white people are more buoyant right?

Look to the right edge of the gif. There is another child whose tube overturned. Which child was more likely to drown? We don't even need to pay attention to the physics. We can just rely on the raw drowning rates!

 

[Juma]

It is now looking as though the body-density explanation has strong predictive power, and I think the habit of blaming black problems on drug abuse or whatever needs to take a back seat in this case.

Predictive power? Predict what? And ignoring real problems because it shameful? You sure are a dumbass.

 

[ApostateAbe]

It is now looking as though the body-density explanation has strong predictive power, and I think the habit of blaming black problems on drug abuse or whatever needs to take a back seat in this case.

Predictive power? Predict what? And ignoring real problems because it shameful? You sure are a dumbass.

It is not that the drug-abuse explanation is shameful. The shame of it does not bear on the probabilities, and we are on the same page on that point. The reason it needs to take a back seat is its lack of predictive power. "Predictive power" means that the explanation narrowly predicts the data. If there is differential drug abuse rates, we may or may not expect significant differences in drowning. But, the hypothesis of differential body densities--it is powerful on many fronts. It narrowly expects differential drowning rates. It would actually be bizarre if we did NOT find differences in drowning rates given confirmed differences in body densities. Not only that, but it predicts differences in psychological swimming ability: you are less likely to learn if you are more likely to drown while doing it. There is some degree of predictive power of the explanation of differential psychological swimming ability alone--it predicts differential drowning rates--but there is no powerful explanation for the existence of the difference in psychological swimming ability except for differences in body density.

 

[GenesisNemesis]

Has anyone defined race yet?

 

[ApostateAbe]

Has anyone defined race yet?

Races are populations with allele frequencies differing from the allele frequencies of other populations within the same species due to differing ancestral geographies. It is a biological concept essential to the theory of evolution. Many people do not fully accept the theory of evolution (or they think they do but they really don't), so, if you are one of those people, then feel free to take a step backward so we can talk about the general biology of race, as it would be more difficult to explain the racial differences in body density if you have not accepted that populations of humans have differentially evolved, and you are likely to be skeptical of the data concerning body densities.

 

[GenesisNemesis]

Races are populations with allele frequencies differing from the allele frequencies of other populations within the same species due to differing ancestral geographies.

Then it should be possible to determine what race someone is by looking at their genetics, yes? Has anyone done this yet?

 

[ApostateAbe]

Races are populations with allele frequencies differing from the allele frequencies of other populations within the same species due to differing ancestral geographies.

Then it should be possible to determine what race someone is by looking at their genetics, yes? Has anyone done this yet?

Yes. It is now standard and common. You can find your geographic ancestries (they don't use the word "races") by ordering a DNA sample kit from 23andMe.com (or a competing DNA testing service) and sending it back with your spit sample. They will tell you not just one race but the percentage of each race represented in your genome, looking at hundreds of microsatellites (races are identified by the frequencies of those genetic markers). Police departments use this technique to find the races of suspects who leave behind DNA at the crime scene. The races identified by DNA almost always match the races that the subjects identify as, and they typically match the races identified by external observers (external identification is more difficult for the more mixed-race subjects).

 

[ApostateAbe]

As you can guess, the common pseudoscience bothers me, and I don't blame you for accepting it, because the pseudoscience about race (that it is impossible to identify by DNA) has been heavily promoted by those sources that are typically trustworthy, such as PBS and Bill Nye. They prove the point to their audience only by using a small number of genetic markers to fail to identify races, not hundreds,

 

[GenesisNemesis]

As you can guess, the common pseudoscience bothers me, and I don't blame you for accepting it, because the pseudoscience about race (that it is impossible to identify by DNA) has been heavily promoted by those sources that are typically trustworthy, such as PBS and Bill Nye. They prove the point to their audience only by using a small number of genetic markers to fail to identify races, not hundreds,

Where have I said I've accepted anything? I'm merely asking questions, as I'm fairly ignorant about genetics.

 

[ApostateAbe]

As you can guess, the common pseudoscience bothers me, and I don't blame you for accepting it, because the pseudoscience about race (that it is impossible to identify by DNA) has been heavily promoted by those sources that are typically trustworthy, such as PBS and Bill Nye. They prove the point to their audience only by using a small number of genetic markers to fail to identify races, not hundreds,

Where have I said I've accepted anything? I'm merely asking questions, as I'm fairly ignorant about genetics.

Cool, please accept my apology.

 

[RavenSky]

What is the density of a very lean human body?

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True. All 4 City of Atlanta indoor (and thus year round) swimming pools have been built in predominantly black areas.

I was thinking more of outdoor pools--they are more common in warmer climates. Blacks tend to be in warmer areas because that's where they were brought as slaves.

Poor people disproportionately do not know how to swim because they are raised in homes without swimming pools. Low income housing generally do not have swimming pools. Low income schools generally do not teach swimming. The outdoor pools in the south are at middle and upper income homes.

My mother was raised dirt poor. She did not know how to swim. She was not black, and her inability to swim had nothing to do with bone density or the color of her skin. It had everything to do with being poor as a child, and thereby never having the opportunity to learn to swim.