Thursday, May 23, 2019

A recent paper claims that human traits are basically produced by genes and luck

Authors of a paper published earlier this year in Behavior Genetics have made arguments similar to those of  HBD writers Greg Cochran and JayMan: psychological traits are basically the result of 1) genes, and 2) noise. 

Years ago, behavioral geneticists discovered that the environments shared by siblings have little impact on how you turn out. By contrast, the environment you experience that is unique to you appeared to be about as important as genes -- both of them explaining roughly half of the story.   

The authors, two Russians from St. Petersburg University (they're Russians, so they must be evil) explain that research trying to identify specific factors from the unique environment that are important has been mostly unsuccessful.  Factors like illnesses and accidents typically explain less than 3% of the examined traits.

In addition, genetic research (mostly experiments on animals) has shown that traits depend a great deal on stochasticity--a fancy term for randomness, or "luck."  For instance, ultraviolet rays increase genetic mutation rates in organisms, but exactly which genes will be affected is a stochastic process. Random genetic errors that occur in the early stages of embryonic development will be more consequential; in this case, all the descendants of the initial mutant cell will also be mutant. 

Complex organic systems like the human body or brain are especially likely to be shaped by random events. For example, in female embryos, one of the two X-chromosomes is inactivated as a Barr body.  Each cell will make a random 'decision' which X-chromosome (the paternal or maternal) gets inactivated, and the 'decision' is maintained in subsequent cell divisions.  As a result, the female becomes mosaic.  In heterozygous females with the EDA mutation, you get ectodermal dysplasia which leads to an absence of perspiratory glands.  Depending on what X-chromosome is active, some skin areas are defective in sweating, while other areas are normal. The mosaicism is random.  Even identical twins raised in very similar environments will differ significantly.

Another human example is the growth of synapses in the developing brain.  While the number and locations of these connections are under some genetic control, research has demonstrated a significant stochastic component.  So again, identical twins raised the same will end up with brain wirings that are somewhat different, this is simply due to random differences in development, and it can cause behavioral differences.

These authors do not mean that these random factors are actually causal factors that simply have not been identified yet. They are claiming that pure randomness is simply a key part of our development, and the hard determinist view is simply incorrect.

They don't touch the political implications of all this, but I'll jump in.  To summarize, it's only a little bit of a simplification to say that we may be the product of genes and random events.  Genetic research is also telling us that hundreds or thousands of genes influence a trait, but each only a trivial bit, so simple pathways for intervention and improvement might be hard to find.  And you can't control randomness, so there seem to be fewer and fewer possibilities for government to step in and effectively address social problems -- at least in ways acceptable to liberals.  The old-time conservative who contended that human nature is tragically flawed and that one must resign oneself to human limitation seems more and more like a prescient, wise person.     

Friday, May 17, 2019

How are we doing on mixing the races?

One of the strongest findings in sociology is that people follow the principle of homophily--they naturally associate with people like themselves.  It goes without saying that sociologists never take the next logical step and conclude that this universal tendency is rooted in biology; that it is very resistant to change; that it's counterproductive to swim against a very strong tide. The typical view of a sociologist when it comes to a social universal is, "Yes, we see it everywhere, so naturally, we should get rid of it!"

Nowhere is this truer than in the case of race.  Around the entire globe, people of the same race tend to gravitate to each other, so in America, we're bound and determined to see the day when a random white person has all non-white buddies.

So how are we doing on this?  I looked at a question given in the General Social Survey where participants were asked to list friends (sample size = 1,300).  I assume that the first person mentioned is a close friend, if not the closest friend.  When the respondent is white, how often was the first friend mentioned white? Two percent of the time.  Black respondents first mentioned a white friend 11.2% of the time.

If making friends were truly random, the distribution of friends would match the racial distribution of the population. (We'll set aside the goal of preferring friends from other races.)  For example, 13% of the first friends mentioned by whites should be black since blacks are 13% of the population.  But when I do the math that takes into account the size of the black and white populations, blacks are 37.1 times more likely to say their first-mentioned friend is black rather than white. A white is 9.3 times more likely to mention a white person.  I doubt the numbers were much different in 1960.

For all America's efforts, biology seems to be stronger than sociology.

Tuesday, May 14, 2019

Which explains how prestigious your job is--intersectional theory or HBD?

On Twitter, Steve Sailer writes, "The pattern that gay black males tend to assimilate into white corporate culture better than do straight black males deserves more social science attention than it has received.  It's hard to notice if you are Woke and believe in the conventional wisdom about Patriarchy, etc."

Let's test this kind of idea with General Social Survey (GSS) data.  Based on intersectionality theory--experiencing more discrimination with each additional minority status--job prestige rankings should look something like this:

Top Tier--Zero Strikes Against
Straight white male

Second Tier--One Strike Against
Straight white female
Gay white male
Straight black male

Third Tier--Two Strikes Against
White lesbian
Straight black female
Gay black male

Fourth Tier--Three Strikes Against
Black lesbian

By contrast, biological theory would focus on traits that are important for high-status jobs, and the obvious candidate is intelligence and the glaring racial gap in IQ. So this view would predict that the big divide will be race, with whites above average in job prestige and blacks below average. The other demographics shouldn't matter much. 

And what are the facts?  According to GSS data for 19,901 respondents: 

Mean occupational prestige 

Gay white male  47.1
White lesbian  46.2
Straight white male  45.2
Straight white female  44.5

Total Sample  44.2

Black straight female  40.9
Black gay male  40.7
Black lesbian  39.8
Black straight male  39.2

As predicted, the major divide is race.  All whites are above average, and all blacks are below.  If intersectional theory were true, black lesbians would be on the bottom, and straight white males would occupy the top position.  Neither is the case.  Biological theory would predict no disadvantage for homosexuals--in fact, I reported in a previous analysis that they have above-average IQs--and indeed they do well.

And relevant to Steve's point about black males, homosexuals do better than straights, which contradicts the claim that it's all about intersectional discrimination.

Biology explains more than sociology.

Thursday, May 09, 2019

Is gay liberation leading to gay genocide?

Look at this graph (GSS data) which shows the mean number of children that gay men ages 40-64 have for the past four decades:

In the 80s, the average gay man had two kids.  By the 90s, the number had dropped to .81, and in this decade, it's down to .58.  In other words, a gay man 40 years wasn't that different than a straight guy in terms of offspring. Now, he has less than 30% the family size of a heterosexual.

While Greg Cochran is right that the heritability of homosexuality is not high, there seems to be some genetic influence, so it's ironic that gay liberation is leading to fewer people with genes that raise the odds of homosexuality.  That implies fewer and fewer gay men in the future.  Strange, but I don't hear anyone accusing liberals of secretly pushing for the slow genocide of homosexuals. 

Monday, April 29, 2019

Data: Dot Indians are the most industrious Americans. Feather Indians, the least. Hispanics are in the middle.

Sociologists assume that a man lacking a job is the fault of the economic system. He would take any job if it were simply available.  Common sense and behavioral genetic research contradict this. Industriousness is largely caused by genes, and people vary a great deal in this trait. Some people cannot take it easy, and some cannot not take it easy. I've talked to many people over the years who refuse to take jobs that are not acceptable to them.  That's the reality in America. Sure, you might have a small percentage with REAL health problems, but those are the exceptions. 

So I'm going to use full-time work as a measure of industriousness.  I'm interested in racial and ethnic differences. Men and women still differ in employment, so let's focus on just the men. Here are the percentages of American men ages 30-64 who are employed full-time listed by ethnic group:

Percent employed full-time

Asian Indian  85.0
Jewish  84.0
Dutch  84.7
Portuguese  82.6
Japan  82.2
Russian  81.8
Spanish  81.8
Greek  81.6
Romanian  80.0
Polish  79.3
German  79.1
Mexican  78.7
Italian  78.6
West Indian  78.6
Danish  78.5
Norwegian  77.6
Austrian  77.5
Scottish  77.5
Chinese  76.9
Hispanic  76.9

US Total  75.7

Irish  75.7
English/Welsh  75.4
Czech  74.8
Swedish  75.3
French Canadian  75.1
Belgium  75.0
Arab  74.7
Hungarian  73.5
French  72.9
Filipinos  71.4
Muslim  71.2
Puerto Rican  68.6
Black  67.4
Lithuanian  67.4
Finnish  66.7
American Indian  55.6

Looks about right. For a moment, let's compare the top group with the lowest. If it were true that discrimination determines who works, why would Asian Indians surpass every single white group?  Wouldn't a bigot choose the lamest white person over a South Asian?  While American Indians are also non-whites, at least most of them are Christians. Wouldn't a bigot choose a Christian over a heathen Hindu?  American Indians have a tragic history, and whites feel bad about that. They were here long before Europeans. Wouldn't an employer choose a Real Red American over an immigrant invader, just off the boat?

And yet, Asian Indians tower over all other groups. Why? Because biology explains better than sociology.

By the way, I'm at a cafe, and seated at the next table over is a Native American. He's super friendly. He's always here, and I'm not sure he's old enough to be retired, but he doesn't seem particularly busy. The Asian Indian guy I always see here is also popular, but he owns a business and uses the cafe to network.

Sunday, April 21, 2019

Data: In some cities, 3 out of 10 black men had sex before they were 13 years old

Look at this table from a study of the age at first sexual intercourse among males:

Depending on the city, 12 to 29% of black males have had sex before age 13. This is compared to 2 to 9% of white males.  The numbers for Hispanic males are 6 to 17%.

These stats support the view that blacks are shifted toward "fast" life history strategies. Along with shorter life expectancies and less investment in each child, life history theory claims that "fast" individuals mature more quickly and become sexually active at earlier ages.  Even though the study does not report figures on Asians, I'm confident they would be the lowest group.

Friday, April 19, 2019

Data: Despite liberation, gay men are less happy than in 1980

The General Social Survey asks participants, "Taken all together, how would you say things are these days - would you say that you are very happy, pretty happy, or not too happy?"  I calculated the mean happiness for gay males over the past four decades.  Here is the graph:

In terms of liberation, life has been good for homosexuals since 1980. Approval of homosexual sex by the general public has skyrocketed.  When I was an undergraduate, gay marriage was not even on the radar for progressives. Now it is the law of the land.  An openly gay man -- Buttigieg -- is a popular Democratic presidential candidate. In my department meeting Wednesday, a colleague boasted that her son now identifies as gay, making us all feel inferior because our kids are straight.

All this progress and liberation has really delivered on gay happiness, right?  Actually, mean happiness has dropped in every decade. Homosexual men are less happy than they were at the height of the AIDS epidemic. 

This reminds me of female liberation. Women are also less happy. Look at the graph.

Liberation has not delivered.

Monday, April 15, 2019

Data: I'm skeptical that the Hispanic crime rate is similar to that of whites

I doubt the Hispanic crime rate is similar to that of whites. Let's put aside police statistics and victim surveys because both depend on someone reporting the crime, and immigrants are notorious for failing to report crimes out of fear of authorities.  And arrest data also depend on law enforcement policies.

Criminologists understand that homicide is a good measure of serious violent crime because corpses advertise crimes loudly.

The CDC has a neat website for analyzing mortality data.  I looked at homicide rates for 2017, the most recent year available. Here are the rates per 100,000 in the specific population:

Homicide Rate
Black  23.0
American Indian  9.7
Hispanic  5.3
White  2.8
Asian  1.7

Not surprisingly, blacks are at the top with a rate that is 13 1/2 times the Asian rate.  American Indians are second with a rate that is 5.7 times that of Asians.  This reminds me of Greg Cochran and Henry Harpending's hypothesis (if I remember correctly) that Native Americans never got pacified by centuries of the state weeding out the most violent.  Henry and Peter Frost published a paper three years ago that found that the English proclivity to execute criminals with abandon resulted in a country with a homicide rate that is a tiny fraction of what it was a 1,000 years ago.

Criminologists excuse black violence by blaming criminogenic urban environments. If living in a big city is the key to violence, why are rural Indians so murderous? Genes explain better than sociology.

When it comes to homicide, Hispanics resemble their racial reality: they are somewhere between American Indians and whites. Looking at Latin America, I'm pretty sure crime is a more serious problem for Hispanics than it is for whites.

Sunday, April 14, 2019

Data: If Taleb is right that IQ is a BS measure, why do higher scorers have big brains? And why the perfect racial rankings?

A 2015 meta-analysis of 88 studies found that the correlation between human brain volume and intelligence is .24, a small-to-moderate size relationship.  In new research that re-analyzed the data from the 2015 study, the authors showed that the strength of the link depends on how well IQ is measured and the degree to which studies include a full range of values for brain volume and IQ (For example, if only college students are included, many lower IQ people will be excluded, and this will shrink the correlation.)

Based on their analysis, the researchers estimated that the true brain volume/IQ correlation is around .40 -- a fairly strong correlation.

Keep in mind that many researchers have reported racial differences in brain volume that match up with IQ differences. Rushton and Ankney (2009) summarized the research. For example, Beals et al. (1984) measured the endocranial volumes of close to 20,000 skulls from around the world. The Asian-black gap was reported to be a roughly 150 cubic centimeter advantage for Asians.

If IQ is BS measure like Nassim Taleb says, why do high scorers have big brains? 

Friday, April 12, 2019

Sociologists like to crow about the immigration-low crime connection, but it undercuts their own theories

For the past few decades, conservatives have been linking illegal immigration to crime. In response, a whole new literature appeared among liberal researchers showing that more immigration results in less crime.  In usual liberal fashion, they treat illegal immigration as the same thing as legal or overall immigration.

But let's not get into that literature -- that's a discussion for another day.  I'm interested in the fact that social scientists have spent a great deal of energy for more than a century concocting excuses for why poor minorities -- immigrants or native-borns -- are so heavily involved in crime.  The list is long: 1) low crime neighborhoods require years of committed investment in institutions charged with socializing youths, and migrant neighborhoods lack to residential stability, resources, and population homogeneity needed to build effective institutions; 2) migrants tend to come in with low human, social, and cultural capital which makes a criminal career more attractive; 3) due to America's xenophobia, migrants are blocked from opportunities to become integrated into mainstream society with its middle-class jobs and middle-class values; 4) the youthful migrant is torn between Old Country traditions of his parents and the lower-class American values of his native-born peers. Such alienation leads to crime.  And the list goes on and on.

But for these sociologists, refuting conservative claims takes priority over consistency. After a century of predicting lots of immigrant crime, now they're scrambling to explain why immigrants are better behaved than the rest of us, and, of course, everyone knows that they always have been better than us. 

After a century of telling us that communities must be slowly built up into an ecosystem of strong institutions that effectively control the behavior of adolescents, now they tell us that people who just crossed the Rio Grande and found some shack to live in instantly create stronger communities than groups who have lived in a neighborhood for generations. 

The kid whose parents come from Honduras, Guatemala, and El Salvador enjoys a rich, healthy culture that actually frowns on crime, unlike mainstream American culture. Being forced into barrios and excluded from white society is a good thing because these Hispanic communities are tight-knit, while mainstream society is atomistic and dog-eat-dog. These researchers are hilarious.  They truly suck at predicting the future, but they are very skilled at concocting explanations after the fact.

Friday, April 05, 2019

Data: What is the average IQ of your healthcare providers?

I get annoyed when a low IQ kid gets my fast food order wrong, but no biggie. It's a different story when my child is sick and needs medical treatment. 

What is the mean IQ of health care workers?  To get a sufficiently large sample (GSS, no immigrants), I included the following jobs: physicians, dentists, optometrists, podiatrists other health diagnosing practitioners, registered nurses, pharmacists, dietitians, physical therapists, speech therapists, and other therapists. 

For the whole group, I get a mean of 104.8. Not good. For occupations with at least 10 survey respondents:

Mean IQ

Physicians  114.5
Dentists  108.4
Registered nurses  104.6
Pharmacists  108.2
Dieticians  90.9
Physical therapists 110.6
Speech therapists  104.6
Other therapists   109.4

All of these numbers are discouraging. Don't take advice from a dietician.  

What about race? We can only look at the overall mean for all healthcare providers. For whites, it's 105.9; for blacks, 96.1; and for other races, it's 99.2.  A little bit scary.   

And gender? 109.9 for men, and 103.5 for women. 

Interpreting Your Genetics Summit

Tuesday, April 02, 2019

Data: Compared to dumb people, are smart individuals more interested in politics?

I've always assumed that smart people are fascinated by politics. One complaint I have of social scientists is that they're so obsessed with politics, they can't conduct fair research. (But I can hear you saying, "You said SMART people.")  Anyway, is my assumption correct? Is it different for men and women?

The General Social Survey asked respondents: "How interested would you say you personally are in politics?" Answers ranged from 'very interested' to 'not at all interested.'  I measure IQ with a 10 question vocabulary quiz (sample size = 1,141):

Look at how those scoring a perfect score on the test are much more interested in politics than any other group. To get precise, the correlation between the two variables is .20 -- a moderate relationship.

Now for the women (sample size = 1,507):

I separated by sex because I suspected that the rise in interest as one moves up the IQ scale might be sharper for men. My experience is that smart women are more interested in politics than less intelligent women, but I see more intensity among men.

The female pattern is similar to that for men. The correlation is slightly weaker -- .18. The gender gap is pretty visible at the highest IQ level: 16.8% of these women have little or no interest, compared to only 5.4% of the men.

Interpreting Your Genetics Summit

Sunday, March 31, 2019

Data: What predicts believing that the environment is more important than genes?

In the last post, we looked at ethnic differences in whether the environment or genes are thought to be more important for a variety of traits. Now let's see which factors predict choosing nurture over nature.

Using GSS data, I estimated linear regression models (OLS) with each of the four questions as dependent variables, plus a scale of all four of them summed.  I included all demographic predictors I could think of, including: sex, age, race, southern region, immigrant vs. native-born,  educational level, income, church attendance, number of children, and political orientation. I list below the significant effects (beta weights are shown):

Black  -.15
Education  .10

So blacks, compared to whites, and less educated people think environment is less important. Race is the more powerful predictor.

Alcohol Abuse
Female  -.08
Education  .07

Females and the less educated think genes are more important for alcohol abuse.

Female  -.06
Black  -.06

Women and blacks are shifted toward seeing genes as important for altruism.

Education  .06
South  -.07

For athletic ability, Southerners and the less educated tend to see genes as being more important.

Nurture over nature scale
Black  -.11
Education  .11

When the scores for all four questions are added together to make a scale, blacks and the less education are shifted toward genes having the most impact.

Not surprisingly, people exposed to more education tend to believe in the power of the environment. After years of getting the same message from liberal teachers, what do you expect?  It is a surprise, though, that blacks, after adjusting for education, give higher estimates to the power of genes.

UPDATE: It might surprise you that political orientation (liberal vs. conservative) is unrelated to one's view of the importance of genes. 

UPDATE II: I wonder if the race difference comes from the fact that blacks are more fatalistic than whites, and people tend to assume (wrongly in my view) that genes imply determinism but environment does not. Whites might embrace nurturism because it sounds compatible with the idea that we can take control of our lives and improve things.  

Thursday, March 28, 2019

Data: Do Americans think genes or environment are more important?

Do Americans think people act like they do because of environment or genes?  The General Social Survey gave respondents four scenarios:

1) Carol is a substantially overweight White woman. She has lost weight in the past but always gains it back again.

2) David is an Asian man who drinks enough alcohol to become drunk several times a week. Often he can't remember what happened during these drinking episodes.

3) Felicia is a very kind Hispanic woman. She never has anything bad to say about anybody, and can be counted on to help others.

4) George is a Black man who's a good all-around athlete. He was on the high school varsity swim team and still works out five times a week.

Respondents were asked to estimate the influences of environment versus genes for each scenario. Answers ranged from 100% genes (scored as a 1) to 100% environment (scored as a 21). 50/50 would be scored as an 11.

I summed the scores for these four questions, and list the means for ethnic groups below (sample size = 1,842):

Mean environmentalism score

Asian Indians  56.7
Scottish  54.9
Czech  52.6
Italy  52.1 
Filipinos  50.9
American Indians  50.9 
Norwegians  50.9
Russians  50.4
Chinese  50.2
Polish  50.1
English/Welsh  49.9
Jewish 49.4
Irish  49.3

All Americans  49.3

German 49.0
Dutch  47.9
Swedish  47.3
Mexican  47.1
Puerto Ricans  46.3
Danish  46.1
Blacks 45.2
French  44.2
Spanish  43.9

The mean score for all Americans indicates that the average person thinks the traits described are 55% due to environmental influences, and 45% due to genes.  This is not far from the truth as indicated by genetic research. Americans seem to be ignoring their environment-is-all social science teachers. On the other hand, I'm sure by "environment" most people are thinking of experiences which siblings share -- families, schools, etc -- but research clearly shows that these factors are not important.

The highest scoring group, Asian Indians, thinks the traits are roughly 65% environment.  The lowest group, people of Spanish descent, put the estimate at about 50/50.  Hispanics, in general, tend to think genes are more important than other groups. This tendency is also true for blacks, but other non-whites -- Chinese, Filipinos, Asian Indians, and American Indians -- think the environment is more important.  It's surprising that several poor minority groups think genes are so important.  The gap between Asian Indians and the Spanish is eight-tenths of a standard deviation -- a large difference.

Interpreting Your Genetics Summit

Tuesday, March 26, 2019

Data: What are the best predictors of voting for Trump?

It's always exciting for nerds like me when new GSS data arrives. 2018 is now available. They asked respondents whether they voted for Clinton or Trump. I used logistic regression to determine what predicts voting for Trump (sample size = 904):

Voted for Trump 
Male  .57
Southern region  .33
Black  -3.78
Other race  -1.30
Education  -.11
Income  .01
Church attendance  .16

The coefficients are not standardized, so they can only tell you the direction of the relationships, not the magnitudes. I included age and IQ, but neither one was significantly related to vote choice.  Keep in mind that the relationships are net of the influences of the other factors included in the model, so, for example, age might predict voting for Trump because older people are whiter, wealthier, less educated and more religious, not because they grew up in an earlier era.

So here are the characteristics of people voting for Trump: male, Southern, white, less educated, higher income, with more church attendance. No surprises there. And what mattered the most in order from most to least predictive: 1) white, 2) church attendance, 3) male, 4) education, 5) income, and 6) southern residence.  Trump owes the election to religious, white males, like myself.  You're welcome.

I didn't have data on the impact of Russian colluders.

Interpreting Your Genetics Summit

Friday, March 22, 2019

Data: How can the LGBT suicide rate be so low in a country that is supposedly so homophobic?

In this new study of over 120,000 suicides, the authors reported that 0.5% of the suicides were LGBT.  They also cited an estimate that 4.1% of Americans are sexual minorities. This suggests that they have a much lower rate of suicide than heterosexuals.

The authors speculate that sexual minority status of many suicides go unknown and unrecorded. If LGBT's had the same suicide rate as heteros, only 12% of them had their sexual orientation recorded correctly. I find this hard to believe.

It is safe to say that, according to this data, sexual minorities, like blacks, have a low rate of suicide. How is that possible, in a country that is supposedly so homophobic, supposedly so hateful?  The answer is that America is not a hate-filled country. It's an impressively tolerant country.

Interpreting Your Genetics Summit

Tuesday, March 19, 2019

Data: Which explains American social mobility better? Sociology or biology?

I remember the first department party I attended as a PhD student in sociology.  I joined a conversation between a young faculty member who specialized in social mobility and a professor who was an international expert on urban sociology. I was stunned when the older guy said to the young guy, "Why do you study American social mobility? There is no such thing."

I had a bigger mouth then, and said, "Could've fooled me. My parents never stepped foot on a college campus. I have one brother working on his JD and another has a BS in business and will probably make double what I end up making." (Turned out to be more like three times as much.) He said something about exceptions and moved on to something else.

So the sociological view is that kids inherit the social class of their fathers because the system is rigged that way. The logic of this theory is that there should really be few exceptions. The genetic view, on the other hand, is that since children get their genes from parents, they will tend to end up where their parents are, but since each child gets a unique combination of genes, and since each child is exposed to unique developmental events, offspring will often depart from the class of their parents by either moving up or moving down. The pure sociological view has no explanation for these departures. An open, fluid, meritocratic America is a fiction, according to these people.

What does the General Social Survey say?  You can see below a contingency table of father's and offspring's highest degree earned (sample size = 1,325, ages 30-39, years 2010-16). (I use education because we have data for both generations):


As both theories predict, there is a tendency to end up where the old man did, but there are PLENTY of exceptions. 
Adding up all the cells where the kids went further in school than dad, we get 35% of the total. If we do the same for all offspring that fell short of their father's education, we get 15% of all respondents. Yet we're told you're never supposed to be able to fall in American society where privilege reigns. 

Intergenerational stasis happens to just 50%. This pattern is consistent with a genetic/developmental theory of outcomes. It does not support the opinion of my America-hating professor.

Interpreting Your Genetics Summit

Meta-analysis: Religious people do less self-injury

This new meta-analysis synthesizes the results from 16 studies (total sample of 24,767) that examined the relationship between religiosity and non-suicidial self-injury (e.g., small cuts on one's arms).  The researchers found a small negative correlation, meaning that more religious people are less likely to intentionally injure themselves.

This result is based on correlations which don't tell us what is causing what. Religious involvement could lower self-injury, or some trait like good mental health could both lead to more church and less hurting oneself.

Since I've come to see biology as so important for explaining behavior, I'm inclined to interpret the MANY ways religiosity predicts good outcomes to mean that people who have positive traits are more likely to value religion. I'm inclined to see religiosity as a marker of positive traits.

Sunday, March 17, 2019

Data: Northern Europeans make the best Americans

American needs smart people, especially those who excel in science.  We also need people who believe in core American values, and I think perhaps the best single General Social Survey question to measure this asks respondents if they feel that someone who believes in racial inferiority should be allowed to give a public speech on the topic. Denying this right to people, in my opinion, is the type of behavior that belongs somewhere else, not America.

To capture which groups score highest on the above qualities, I created a scale that sums measures of IQ, basic scientific knowledge, and favoring free speech.  Here are the mean scores for any ethnic group with at least 10 respondents (sample size = 985):

Mean desirability score

Russian  22.72
English/Welsh  21.73
Swedish  21.43
Norwegian  20.93
Scottish 20.78
Irish  20.56
Jewish  20.54
French  20.47
German  20.28
Dutch  20.27
Polish  20.19
Italian  19.63

Total US  19.61

American Indian  19.07
Chinese  18.55
Spanish  18.15
Black   17.78
Asian Indian  17.42
Portuguese  17.30
Puerto Rican  16.17
Mexican  15.83

Russians score the highest, and northern Europeans, in general, do well.  Southern Europeans and non-whites tend to do poorly.  The gap between Russians and Mexicans is 1 1/2 standard deviations -- an enormous difference.  (I included immigrants to maximize sample size, but rankings don't change much if I exclude them. The Chinese and Mexicans rise a little.)

If the US had a rational immigration policy, we would be growing the top groups.  The country, however, desperately blinds itself to these kinds of facts, so we are growing the bottom instead.

Interpreting Your Genetics Summit

Friday, March 15, 2019

Data: Polygenic scores predict educational attainment among blacks

This new study looked to see if polygenic scores for educational attainment that have been developed from samples of white people work for blacks (sample size = 1,050). A polygenic score sums up how many variations in locations on genes a person possesses that have been correlated with the outcome variable, weighted for the strength of the relationships. In plain English, the higher your score, the higher your genetic risk.

The researchers found that, even though blacks have a genetic history that is very different than whites, the polygenic scores that were developed for whites significantly predicted going to college among blacks. While scores did not predict reading achievement, they did predict math achievement.

Bottom line: genes matter. They matter for whites, they matter for blacks.   

Wednesday, March 13, 2019

Is there such a thing as a "superior race"?

In the last post, I analyzed answers to a General Social Survey question about whether one approves of someone who believes in the genetic inferiority of blacks being able to give a public speech about it.

That got me wondering, "Do I believe there are inferior and superior races?"

Some people might think of the question in terms of human accomplishment and might consult Charles Murray's book. I would call this an example of the social construction of superiority.  One group might value cultural achievement, some other group might value something else (e.g., the most pious group is the best).

With this kind of evaluative question, I typically take one of two approaches: either as a Christian or as an evolutionist. Since my religious values are not very interesting, I'll set those aside.

As an evolutionist, I'd say the simple, current answer in the context of the United States is that the superior races are: 1) Mexican Americans, 2) American Indians, and 3) blacks.

Why?  Because nature's definition of "superior" refers to how well one is adapted to his environment, and that is measured in terms of reproductive success -- who is having the most children. And we know from GSS data that three groups average the most kids (women ages 40-55, years 2010-2016, sample size = 1,156):

Mean number of offspring

Mexican  2.87
American Indian  2.57
Black  2.47

White  2.02

Whites are a much less successful group with an average around two.  And among whites, the biggest losers are people of Polish descent who have a mean of 1.56 children (looking at groups with at least 20 respondents).

Now, you can get more sophisticated about it and argue that evolution is about survival, and in the long-term, groups who are the most scientific are in the best position to survive, and that would be whites with northeast Asians also showing a lot of ability.  I would argue that the current fertility situation is much more certain than the future, and (non-Asian) minorities are thriving. 

UPDATE:  I should also say that I do possess a strain of modernism in me which is utilitarian: if our criterion of superiority is contributing the most to the welfare of the greatest number of people, whites win.

UPDATE II: The fertility gap between Mex-Ams and whites is fairly big: six-tenths of a standard deviation.
Interpreting Your Genetics Summit

Tuesday, March 12, 2019

Data: Compared to the 1970s, support for free speech is lower among college-age Americans

Since 1972, General Social Survey participants have been asked the following question: "Consider a person who believes that Blacks are genetically inferior. If such a person wanted to make a speech in your community claiming that Blacks are inferior, should he be allowed to speak, or not?"

I wanted to look at trends among college-age students. Here is a graph (sample size = 2,158):

The green bars indicate the percent who would allow the controversial person to speak. This has fallen from 68.4% during the 1970s to only 48.0% in this decade, a drop of 20 percentage points. 

It looks to me like young people in the 70s were either more open to genetic ideas concerning race, or they were simply more supportive of free speech. 

Another interpretation is that young adults in the 70s were against the establishment and thus favored ideas that challenge the mainstream, while young people today tend to support the establishment and thus support its suppression of unpopular ideas. 

Interpreting Your Genetics Summit

Saturday, March 09, 2019

Data: Which ethnic groups know the most science?

You might assume that a person's knowledge of basic science is merely the result of education or IQ.  But when I calculate Pearson correlations with a 10 question quiz on basic science (e.g., "Who determines the sex of the child -- the mother or the father?") the education/science and IQ/science correlations are of moderate size (.37 and .41, respectively).  Some people simply take to science better than others. I like to call this Sci-Q.

I was curious about how this knowledge differs by race and ethnicity. The numbers displayed below are the mean for any group with 10 or more respondents (GSS data, total sample size = 3,737):

Mean Scientific Knowledge Score

Yugoslav  8.20
Scottish  7.82
Swedish  7.87
Japanese  7.77
Russian  7.55
English/Welsh  7.54
Swiss  7.48
Chinese   7.45
Norwegian  7.42
Polish  7.42
Hungarian  7.41
Austrian  7.40
Lithuanian  7.40
Jewish  7.38
Danish  7.30
French  7.25
Czech  7.22
Irish  7.22
French Canadian  7.17
Greek  7.15
Asian  Indian  7.14
Netherlands  7.11
German  7.10
Italian  7.10
Finnish  7.08

US Total  6.92

Spanish  6.89
Arab  6.88
Portuguese 6.71
American Indian  6.49
Filipino  6.12
Mexican  5.88
Puerto Rican  5.88
Black  5.86
West Indian  5.77

GSS data has the old category of one's family coming from Yugoslavia.  These people are in first place with a very high mean of 8.20.  We can see that Eastern Europeans, in general, tend to do well, as do Northern Europeans and Northeast Asians. 

On the low end, you see blacks, Hispanics, American Indians, and Arabs.

The gap between the highest and lowest groups is almost 1.4 standard deviations -- a huge difference. 

America's future depends on having lots of people who "take to science."  We need high-scoring groups to grow--through their having larger families and/or moving to the United States.

Interpreting Your Genetics Summit

Thursday, March 07, 2019

Data: The big move among American Jews is not to Orthodoxy, it's to no affiliation

Since Orthodox Jews have more kids than other types of Jews, some assume that they are quickly becoming the modal category.  Not so fast. This table show trends since the 1970s (GSS data, sample size = 737):


While the share of Jews who are Orthodox has increased over the past four decades (1.9% to 7.8%), the real movement has been toward being a Jew person with no affiliation. Over this period, unaffiliated Jews rose from 15.1% to 27.5% of the total.  Also--look at the huge drop in Conservative Jews: 43.4% down to only 17.6%.

This seems to be part of the larger social trend of some Americans moving away from religious affiliation of any kind. 

In a previous analysis, I found that less religious Jews are less ethnocentric. 

Wednesday, March 06, 2019

Data: Athletes are more conservative than non-athletes

I would expect athletic people, on average, to be more conservative than non-athletes. The culture of sports and the types of individuals drawn to it are competitive and disciplined, and are likely to attribute their athletic success to their own hard work.

The General Social Survey asked participants to rate themselves athletically. This question was asked in 2004, so to look at voting patterns, we have to rely on a question about whom the respondent voted for in the 2000 presidential election. Here are the results listed by race and sex (sample size = 1,439):

Percent who voted for Bush in 2000

Athletic  63.1
Non-Athletic  53.0  
Relative risk  1.2

Athletic  22.2
Non-Athletic  10.7
Relative risk  2.1

Athletic  53.0
Non-Athletic  48.5  
Relative risk  1.1

Athletic  55.1
Non-Athletic  45.9 
Relative risk  1.2

The data support my hypothesis for both race and gender.

It makes sense for conservatives to actively encourage as many kids as possible to be involved in sports. Or perhaps I should say competitive sports. A trophy for every kid is a liberal idea. 

Interpreting Your Genetics Summit

Monday, March 04, 2019

Data: Taleb is (partly) wrong on IQ

There was an Twitter dust-up recently when Nassim Nicholas Taleb used his statistical skills to trash IQ studies.  Two of his criticisms -- if I understand him correctly (he doesn't write so regular folks can understand because he is an elitist) -- are that: 1) IQ only does a good job distinguishing the mentally challenged from those in the normal range of intelligence; and 2) IQ becomes particularly useless at predicting important outcomes (like income) at the high end of the distribution.

I looked at the relationship between the General Social Survey's simple measure of IQ -- a vocabulary quiz -- and the respondent's household income in 1986 dollars. The vocabulary score is the number correct out of 10 questions (sample size = 27,530):

According to GSS data, Taleb is wrong on his first point and half wrong on his second. See how IQ does not predict income much at all for the lowest four IQ levels.

But it does do a pretty good job of predicting income from levels 3 through 10. Within this range, there is a straight, stair-step increase in income as one moves up in IQ.  This linear relationship does not fade or disappear at the highest levels of intelligence, as Taleb says it does.

On the other hand, the data support Taleb on one important point (you can't see the following on the graph): the problem of heteroscedasticity (unequal variance). For each IQ level from 0 to 4, the variance in income is not high. For example, people at the 0 level do not vary from each other much in terms of income: they're generally pretty poor. Once you reach level 5, people start to diversify more: people are increasingly all over the map in terms of income. And this tendency increases through level 10--the level with the greatest dispersion in income. In other words, while the smartest people have the highest average income, it is a very diverse class of people. Some earns tons of money, others not much.

So, a high IQ seems almost necessary to earn a big income, but it is far from guaranteeing it. 

UPDATE:  The data reminds me that income -- in the US, at least -- is hard to predict because there is so much variation.  Liberals like to refer to it as inequality.  Probably no variable predicts income with a great deal of precision simply because people are all over the map in terms of how much they make.  Taleb takes advantage of that fact when he criticizes IQ.

Interpreting Your Genetics Summit

Saturday, March 02, 2019

Data: What type of immigrants vote for the GOP?

President Trump told the audience at CPAC today that the economy is so strong, we need legal immigrants to fill certain jobs, but it should be based on merit. Unless the GOP wants to become the next Dodo bird, "merit" should be the type of immigrants who vote conservative.

What kinds of immigrants are likely to vote that way?  The General Social Survey asked people which candidate they voted for in 2012.  I looked at immigrants to see what predicted voting for Romney over Obama (sample size = 192).  I looked at sex, age, race, education, IQ, income, religion, and religious attendance.  Only two factors were statistically significant: being white and religious.  Immigrants who are white and go to church often are more likely to have voted for Romney, and being white was the more important predictor.

So if the GOP wants a future, they had better stop the mass immigration of nonwhites and the irreligious.

UPDATE: 62.5% of white immigrants who attend church more than once a week voted for Romney.  By contrast, 96.3% of black immigrants and 75.0% of other non-white immigrants voted for Obama.

Interpreting Your Genetics Summit

Friday, March 01, 2019

Data: Do liberals secretly desire the destruction of blacks?

Author Philip Roth provides a good example of the how the Left feels about sex.  In his novels, he celebrates infidelity.  He loves it, and says that the man who invented faithfulness should never be forgiven.

He's probably not smart enough to see it, but he who loves cheating evidently loves murder, too, because infidelity is a major cause of homicide. The case of the murderous jealous partner is only too common.

Cheating and murder are problems for all populations, but they are particular problems among blacks.  The General Social Survey asked participants, "Have you ever had sex with someone other than your husband or wife while you were married?" Here are the percentages who answered yes (sample size = 20,205):

Blacks  33.8
Whites  21.9
Relative risk  1.5

Blacks  18.6
Whites  13.5
Relative risk 
Relative risk  1.4

So black men are 1.5 times more likely to cheat than white men; the black/white gap for women is similar.

The black homicide rate runs about 8 times that of whites, and some of this difference is due to greater infidelity among blacks. (The data here only addresses marriage, but I assume the racial difference in cheating between single blacks and whites is similar).

Do liberals secretly desire the destruction of blacks?  They've helped destroy the black family by subsidizing single motherhood, they favor abortion on demand which eliminates a much higher rate of black babies than whites, and they favor sexual deviance which encourages murder.

Wednesday, February 27, 2019

Data: Is anti-black discrimination rampant in the US?

General Social Survey respondents were asked, "Do you feel in any way discriminated against on your job because of your race or ethnic origin?"  Here are the percentages (in red) of blacks who answered yes for various years (sample size = 1,031):

America is supposed to be a fatally flawed country because of its deep, omnipresent racism.  It's supposed to be so awful, some people call for a fundamental restructuring--perhaps socialism will fix it.

And the number of blacks who perceive or claim job discrimination (discrimination is hard to be sure about, and some are certainly wrong)?  A whopping 7.7% in the latest year polled.

Gimme a damn break.

Interpreting Your Genetics Summit

Tuesday, February 26, 2019

Key facts about the Catholic priest scandal the Media won't tell you

With the Catholic priest abuse scandal in the news again, someone needs to list key facts that the media never tell us about. The best studies I've seen on the subject have been produced by a John Jay College (CUNY) research team.

1. The abuse epidemic started in the 1960s, peaked in the 1970s, and has fallen off dramatically since. Have you noticed how the victims you've seen interviewed are typically people in their 50s? Most victims didn't come forward until decades had passed since their abuse.

2. The researchers point to the liberal sexual culture of the 60s and 70s to help explain the epidemic. They hypothesize that the behavior of priests and the soft response reflected the broader culture.

3. Over the 60 year period of the study, four percent of priests were accused of sexual abuse. This is the same prevalence typically seen among institutions that care for kids. The prevalence peaked in the 60s and the 70s, fell sharply in the 80s, and has remained at a much lower level. Media and law enforcement attention has been inversely correlated with the problem.

4. Most of the accused priests were accused of a single instance of abuse. Chronic, repeat offenders  were less common, so the prevalence of hardcore predators is much less than 4%.

5. The typical victim was a 12-14 year old boy.  Many older teen boys were also victims. Seminarians were also sexually assaulted by priests.  Girls are typically at greatest risk of sexual abuse, but this has been a male-targeted phenomenon.

The Church should have turned all credible accusations over to law enforcement and should have advocated that offenders rot in jail. Offenders should never have been reassigned and given access to children again.  That is the conservative approach to pedophilia, but the Church, like all major institutions, is not conservative. These people didn't seem to believe that human nature is fallen and prone to depravity.

Since humans are by nature sinners, and men especially so with respect to sexual matters, why would you ever have a policy of allowing men to be alone with children?

Instead, you see a problem that happens all the time in male professions, say, with police, for example: men go easy on their buddies when they act in unacceptable ways. And priests could conveniently fall back on Christian forgiveness and liberal approaches to treating pedophiles to rationalize going easy on buddies.

Priests tell us they will be judged by God more harshly than the rest of us, and I certainly hope they will be because no atheist could ever damage the Church like these priests have done.

And, of course, elites and the Media are salivating over this story since what could be more damaging to the Institution That Is the Embodiment of All That is Evil? (Of course, the liberal Francis is softening them up a bit.)

Saturday, February 23, 2019

Data: Which men get the most sex? The young? The good-looking? The wealthy?

I wondered which factor most strongly predicts men having sex frequently: youth, money, looks, or being married?  Here are the statistical results (GSS data, sample size = 685 men, standardized OLS coefficients, all effects stat. sig.):

Factors predicting frequent sex

Youth  .32
Income  .14
Good looks  .09
Being married  .16  

Being young is by far the most important factor.  Older guys don't have sex nearly as much.  Next in importance is being married.  I imagine many men think you get more sex when you're unattached.  You might get more variety, but not more sex.  A big paycheck comes in third, but good looks is least important for men.

So if you like lots of sex, don't get old.

Data: Which ethnic group has the most beautiful women?

Which ethnic group is the most beautiful?  General Social Survey interviewers -- predominately middle-aged white women -- were asked to rate the physical attractiveness of female participants (US residents) with a range from 'very unattractive' (1) to 'very attractive' (5). Here are the means for various groups (with at least ten participants, N = 1,152):

Mean Physical Attractiveness

Spanish  3.93
Puerto Rican  3.76
Muslim  3.64
East Asian  3.57
Mexican  3.56
Italian  3.55
Asian Indian  3.55
Jewish  3.48
Russian  3.47
French  3.43

Total Sample  3.42

German  3.38
Irish  3.38
Czech  3.36
English/Welsh  3.35
Black  3.34
Dutch  3.27
Polish  3.25
American Indian  3.23
French Canadian  3.23
Scottish  3.16
Swedish  2.92

Asians and and darker Caucasian and Hispanic groups have high means, while fairer whites (e.g., Swedish!), American Indians, and blacks have low means.  The gap between the highest group (Spanish) and the lowest (Swedish!) is over one standard deviation -- a huge difference.

This is somewhat consistent with my judgment -- I would give Spaniards a high score and blacks and American Indians low scores -- but north European women seem at least as beautiful to me as southern Europeans. I would give Greek women (with only four cases, too small include here), for example, a low score.  Eastern European women are beautiful, but Czech, Polish, and Russian women don't do very well here.

I thought ratings by interviewers would be more valid than self-ratings, but now I'm not so sure.  The tastes of middle-aged white women don't line up very well with this middle-aged white dude.

I imagine that many of these survey workers are liberals. Perhaps they penalize fair whites because they're too white.

UPDATE:  I discussed this with my wife, and we wondered if intrasexual competition is influencing the ratings. With the Barbie-type being the traditional American ideal, perhaps interviewers penalize fairer white women. It is weird that these interviewers are giving low scores to the women most likely to match the supposed cultural ideal.  (My wife says she is inclined to unfollow blondes who are just too perfect.)

Friday, February 22, 2019

Data: Are there racial differences in honesty?

Jussie Smollett is just the most recent case of the common phenomenon of minorities orchestrating a hate hoax. This raises the more general question whether racial/ethnic/religious groups differ in how much they value honesty.  General Social Survey respondents (all living in America) were asked how much they prioritize various qualities in children.  One of the qualities is honesty.  Answers ranged from "most desirable" (5) to "least desirable (1)." 

I calculated means for various groups (N = 6,279):

Mean Honesty Score

Filipino  4.28
Japanese  4.25
Finnish  4.21
Portuguese  4.19
Dutch  4.15
Swiss  4.15
French Canadian  4.14
English/Welsh  4.12
Irish  4.12
Scotland  4.12
German  4.10
Chinese  4.08
Czech  4.08
French  4.08
Asian Indian  4.08 

Total Sample  4.08

Danish  4.06
Norwegian  4.05
Italian  4.02
Austrian  4.00
Lithuanian  3.97
Swedish  3.95
American Indian  3.92
Belgian  3.92
Polish  3.92
Spanish  3.92
Jewish  3.90
Hungarian  3.87
Russian  3.79
Romanian  3.79
Black  3.78
Mexican  3.76
West Indian  3.65
Greek  3.47

Certain minorities -- Jews, blacks, Mex-Ams, and West Indians -- have low honesty scores. The difference between the most honest (Filipinos) and least honest (Greeks) is close to one standard deviation, a very large difference.

There is a tendency for southern and eastern Europeans to value honesty less, while northwestern Europeans and Asians tend to have higher means (though there are exceptions).  (I didn't have enough cases of Muslims or Arabs to calculate estimates.)

Saturday, February 16, 2019

Data: Are athletes smarter or dumber than others?

There are positive correlations between IQ and both longevity and height.  Many genes underlie these traits -- it looks like there are health-promoting genes that manifest themselves not only through a long life but perhaps a better functioning brain and ending up taller. And a smart/tall/long-lived person might also have a comparatively small number of mutations that work against health.

Does being an athlete fit in with the rest of these traits?  One might expect height and athleticism to be correlated simply because popular sports like basketball and football favor bigger people.  How about IQ and being a good athlete?  Here are the correlations for IQ and self-rated athletic ability (GSS):

White males (n = 440)   -.05
White females (n = 553)  .01
Black males (n = 74)  -.09
Black females (n = 103)  -.14

For all demographic groups, IQ and athletic ability are either not correlated or a negatively correlated. It does not appear to be the case that there are genes that promote both at the same time (or that subtract from both simultaneously).

Thursday, February 14, 2019

Data: Do brains get you more sex?

Evolutionary psychologist Geoffrey posted the claim on Twitter recently that human cognitive abilities evolved to attract sexual partners.  Greg Cochran responded that there is no evidence that sexual selection has been a significant driver of mental abilities.

Do intelligent people get more sex?  And bottom line: do they end up with more children?  The General Social Survey measures IQ with a vocabulary quiz, so we're measuring verbal ability, a form of intelligence Miller would think is more important for courting than, say, math ability.  I'll focus on ages 18-35 since this is a critical time for sexual competition, and frequency varies with age. Here's a graph of the frequency of sex over the past year (GSS, whites, N = 12,757):

Sexual frequency peaks for men at a mean IQ of 98.  The mean is 3.8 -- 3 means two or three times per month, and 4 means weekly.

Sexual frequency drops off for higher IQ mean, but then it reverses for men in the highest IQ category.  Their average is 3.7.

(Notice how the lowest IQ women have the most sex by far.)

What about kids?  We've already documented that high IQ women have fewer kids, but let's focus on men. This graph is for whites ages 45-60:

For men, peak family size is for those with IQs of 77.  Men at the highest IQ level average fewer children than almost any other group.

There's little evidence here for a verbal IQ payoff.

Tuesday, February 12, 2019

Data: Do religious men have larger families? Do religious people idealize larger families?

We saw in the last post that religious women are having more babies than women who never go to church. What about men?  Here a graph for number of children for men ages 45-60 (GSS, N = 1,251):

The pattern for men is even clearer than for women: guys who attend more than once a week have a much higher mean (2.38) than those who never go (1.61). That's roughly half of a standard deviation difference.

Is this religiosity-fertility link explained at all by differences in attitudes?  Do religious people want more kids?  Look at the graph for the same age ranges (GSS, N = 2,173):

Males are green, and females are purple (I'm a dude, so I won't try to give more precise colors).

There is a small tendency for more religious people to idealize larger families. It seems too small to explain much of the reason why the religious have bigger families. It's probably due to getting married earlier and less willingness to get an abortion if you get a surprise.

NOTE: You have read an updated version.  The earlier version had the error of leaving in cases of those who answered "whatever number people want," cases that were scored an 8.  The results you see above omit these cases (about 6% of the sample). 

Monday, February 11, 2019

Data: The end of religion? Maybe not.

Social thinkers have been predicting the end of religion for many decades.  For example, Auguste Comte (1798-1857) predicted that religious faith would decline as scientific knowledge spread.

Over the past two centuries, religion has proven to be more resilient than thought, but there has been a serious decline in regular church attendance in the US in recent decades, and confidence in the existence of God has slipped some, too.

Modernists like Comte were not aware that at least one powerful factor might work against their hopes of a secular world: genes.  Studies have found that religiosity is influenced significantly by genetic differences. 

And there's a related factor: the correlation between religious involvement and family size.  Look at current data for American women (General Social Survey, women ages 40-55, N= 1,441):

Women who never go to church average 1.92 children, while those who go more than once a week have a mean of 2.48 offspring.  The gap between the two groups is about four-tenths of a standard deviation, a medium-size difference.

Notice how the least fertile women (1.66 kids) attend once per year.  (I'll document in a future post that atheist women have more kids than agnostics.)

Religious people tend to be more conscientious and agreeable than the irreligious, and fertility differences are favoring these genetically-influenced traits.

If the greater fertility of religious women turns out to be a long-term trend, evolution might work against secularization.  Combine this with the mass movement of religious Muslims, sub-Saharan Africans, and Hispanics to the developed world, and Comte's vision might be undermined. 

Wednesday, February 06, 2019

Data: The most athletic women have the fewest kids

Now that I've got a little more confidence that self-rated athletic ability has some validity to it (I also observed that it drops markedly with age), I looked to see if athletic people have fewer children. Here's the graph for women ages 40-55 (General Social Survey, N = 401):

American women who say that "athletic" describes them very well average only 1.58 children, while all the less athletic groups have roughly 2.1 kids.

What about men?  Here's a graph for them (N = 317):

With men, we see a U-shaped relationship: the very athletic group has a mean of 2.39 offspring, and the least athletic men average 2.31 kids.  The average athletic group has the smallest families: a mean of only 1.66 kids.

We could interpret this pattern to mean that highly athletic men are more attractive to women and consequently have more mating opportunities, while the least athletic tend to be low testosterone men who are highly committed to family, which is an alternative path to a large family.

The overall results suggest a mixed trend.  What sticks out to me is that athleticism among women shows that same dysgenic trend with see with traits like IQ, education, and health: the top scoring females consistently have the fewest kids.

And let's not forget the study I linked to that found that athletic performance is highly influenced by genes (heritability = .66).

Tuesday, February 05, 2019

Data: Sex and race differences in self-rated athletic ability

One study of athletic performance put heritability at .66.  In plain English, two-thirds of the differences in athletic ability are explained by genetic differences.

General Social Survey participants were asked to rate how athletic they are on a scale from 1 to 5.  I calculated the means for sex and race combinations (N = 2,373):

Black men rate themselves as most athletic with a mean of 3.57.  White women (2.58) and women of some other race (2.56) come in at the bottom.  The gap between black men and other-race women is nine-tenths of a standard deviation (SD) -- a big difference.

If we focus on just men, the black-white difference is one-third of an SD -- a small advantage for black men.

The biggest within-race gap is among blacks: the male advantage over females is three-quarters of an SD.  The graph doesn't show the overall sex difference: it's over half of an SD.

While it's difficult to rate oneself objectively, these self-ratings seem to have some validity.

Sunday, February 03, 2019

Data: Survival of the fattest?

We saw in a recent post that the women with poor health have the most kids.  Is this true for heavy women, too?  Yes, it is: look at this graph (General Social Survey, self-reported weight, N = 200):

Women with one child are the lightest group with a mean of 165.6 pounds.  Compare this to the heaviest group: Women with seven children weigh an average of 208.5 pounds. The difference is roughly one standard deviation -- huge, no pun intended.

Of course, it's hard for a woman to lose the weight she gains from being pregnant, but it is also possible that genes underlie both weight and fertility.

For example, perhaps women who score low on conscientiousness (self-discipline, long-term planning) lack control over both eating and fertility.

Americans are likely to get fatter and fatter as the generations go by.  If civilization eventually collapses under all the dysgenic trends I have been documenting lately, these fat Americans might finally lose weight due to food shortages.

UPDATE: Readers might suspect that a respondent's weight is due to her height, and perhaps tall women are having more babies.  I checked: fertility does not vary by height. 

Saturday, February 02, 2019

No surprise: Americans in the best position to have a large family are least likely to do so

A good income is associated with positive characteristics like industriousness and intelligence, traits that are strongly influenced by genes.  High-income adults are obviously in the best position to have large families.  Do they?  Look at the graph (General Social Survey, 2010-2016, women ages 40-55, household income in 1986 dollars, N = 1,325):

While women with two children have higher incomes than those with no children, income tends to fall as family size increases beyond two kids.  Compared to families with eight or more kids, two-child families earn more than double the household income.

Here's the graph for men ages 45-60 (N = 1,170):

We see a similar pattern for men, although the income drop beyond two kids is perhaps not as steep as for women. (Don't make much of the high bar for men with seven kids: it's based on only four cases.)

We're seeing the same kind of pattern again and again: Americans who are in the best position to have a big family are least likely to do so.

With these trends, the long-term future will go to the people on the bottom of American society -- the people who have the least genetic potential.

A recent paper claims that human traits are basically produced by genes and luck

Authors of a paper published earlier this year in Behavior Genetics  have made arguments similar to those of  HBD writers Greg Cochran and...