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.

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.

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.

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.

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.

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.

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.   

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.

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. 

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.

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. 

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

Whites
Athletic  63.1
Non-Athletic  53.0  
Relative risk  1.2

Blacks
Athletic  22.2
Non-Athletic  10.7
Relative risk  2.1

Men
Athletic  53.0
Non-Athletic  48.5  
Relative risk  1.1

Women
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. 

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.

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.

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):

Men
Blacks  33.8
Whites  21.9
Relative risk  1.5

Women
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.

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.

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.)

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.)

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.)

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).

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.

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). 

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. 

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).

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.

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. 

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.

Data: Mentally ill women have the most kids

We saw in the last post that women with poor overall health have more kids than healthy women.  This is a bad sign for the long-term health of America.  But what about mental health?

The General Social Survey asked respondents, "Now thinking about your mental health, which includes stress, depression, and problems with emotions, for how many days during the past 30 days was your mental health not good?"

Here is the mean number of bad mental health days listed by number of offspring for women ages 40-55:

Childless women average 3.5 bad days, while women with eight or more kids have a mean of 6.0 bad days. 

Now it's possible that having more children to raise might make one crazy -- I have six kids myself and can testify that it ain't easy -- but it might be the case that people with mental health issues might have less control over their fertility.  The large family size means the next generation has a greater number of genes linked to mental illness, and over many generations, you get a pretty crazy population.  

In pre-modern times, mental illness would work against survival and mating success, but under modern conditions, we see the mentally healthy making every excuse against having kids, while people who simply don't have it together are reproducing like bunnies. 

A perfect example of the current mess is a colleague of mine.  She is tall, beautiful, athletic, healthy as a horse, and very smart (as least as smart as a progressive can be).  She is also nurturing and is exactly the kind of person who should be having kids.  But since the planet is going to melt at any moment, she doesn't want children.  So instead of having a family, she and her husband help the environment by jetting to exotic places every other weekend.  Not good.   

Data: The healthiest women have the fewest kids

Research shows that more than one-third of the variation in self-reported health is due to genetic differences.  Do healthy Americans have most of the kids, so future generations will trend toward good health?  The answer is, no.  Look that this graph that shows the current number of offspring for women ages 40-55 (General Social Survey, N = 965):

Women with excellent health average 2.08 children.  Those with poor health have a mean of 2.32 kids.  Now the gap is only small (one-sixth of a standard deviation), but it's enough of a difference to have an impact over the long-term.

So now we've documented negative fertility trends for IQ, education, and self-reported health. 

Liberals obsess over about how people on the bottom of society have got it so bad (they exclude poor, straight white men, of course), but in evolutionary terms, the bottom is made up of winners.

Data: Current trends might be selecting for low self-discipline

In my view, people in the human biodiversity (HBD) community have a tendency to focus on the importance of IQ to the exclusion of other traits.  Don't get me wrong: general intelligence is IMPORTANT, but so are traits like conscientiousness. 

One reason why we don't write much about personality traits is that the science is not as developed. We typically have to rely on self-report data to measure personality, and such an approach has obvious limitations.

I agree with the view that educational level reflects conscientiousness as well as intelligence.  It's takes planning and self-discipline to stay in school and to spend so much time learning about topics that only we nerds find interesting.

Here's a bar graph depicting the current mean number of offspring for women ages 40-55 by years of education completed (General Social Survey, N = 1,443):

I assume that people with only a few years of education are immigrants from countries where this sort of thing is common.  Women with less than a high school education average more than three kids.  Compare this to the mean of 1.4 kids for those with 20 years of schooling.

Consciousness as well as IQ are heritable, so if I'm right that educational level reflects both, current social trends are selecting for low intelligence AND low self-discipline.  Not good.

Data: Compared to highly intelligent American women, mentally disabled women have twice the number of kids

Now that we've established that US women differ a great deal in the number of children they have, let's look a current dysgenic trends.  This graph shows the mean number of offspring for all women ages 40-55 listed by IQ level (N = 921):

The pattern is no surprise, but it still stings me to see it. Women with IQs of 62.6 average 2.75 kids, while the mean for the highest IQ category (126.3) is 1.44 offspring.

Women below the line for mental disability have families almost twice as large as our most intelligent women.  This dysgenic trend has persisted for some time, and it means that each generation has a little less genetic potential for intelligence.  Not good.

UPDATE:  Once in a while, people ask me what I like to do in my free time. My answer is, "to document the decline of the United States of America."

Data: No, evolution has not come to an end because all women have two kids

I read a tweet quoting Richard Lewontin the other day (can't find the article -- I'd love a copy if someone has one) that suggested that perhaps evolution was coming to an end in modern societies because few people die until they're old, and a model was emerging where everyone has two kids, effectively creating a new generation just like the last.

I hope I read that wrong because it's simply stupid.  It's been more than 40 years since Lewontin presented the idea, so the Two-Child Model should have become even more solidified in US society. Look at this graph to see the current distribution of family size for women ages 40-55:

Does everyone have two kids? Hardly.  The mean is 2.12, while the standard deviation (SD) is 1.49.  One way to interpret SD is to say that if we randomly grabbed two American women in the 40-55 age range, we would expect them to differ in number of children by 1 1/2 kids. (No jokes about half a kid.)

With a normal distribution (known as the "bell curve"), the standard deviation is about 1/6 of the mean, but with this family size variable, the SD is 70% of the mean.  In plain English, women are all over the map in terms of how many babies they have.

Some women (and their partners) are contributing much more genetically to the next generation, and since most traits are heritable, they are shifting the distribution of traits.  That's called evolution, and it's alive and well.

Data: Jewish women with advanced degrees have more kids than their white gentile counterparts

Steve Sailer speculated on Twitter yesterday that "American Jewish total fertility rates are higher than for white gentiles of similar education level and location."  The General Social Survey can help a little here if we are willing to use data from 2000 to 2016. I calculated the number of offspring for white women ages 40-55.  There aren't enough cases to look at Jewish women with less than a four-year degree, or to look at location:

Total number of offspring by religion

Four-year degree (N = 628)
Jewish  1.30
Protestant  1.72
Catholic  1.75

Graduate degree (N = 346)
Jewish  1.96
Protestant  1.49
Catholic  1.62

At the bachelor's level, Jewish is fertility is lower than of white gentiles, but this reverses at the graduate degree level.  It's an atypical, eugenic trend to see Jewish women with graduate degree having, on average, 2/3 more kids than Jewish women with a four-year degree.

It's been about a decade since I analyzed current fertility patterns in the US, so I plan to do that in the next few posts, and to look at correlates I've never examined before.

Data: Lighter blacks tend to be smarter

Recently, I documented that of the four racial groups examined -- whites, Hispanics, Asian Indians, and East Asians-- four showed a positive correlation between lighter skin and IQ.  But what about blacks?

This graph shows mean IQ for blacks born in the US at increasing dark skin tones (as rated by General Social Survey interviewers, N = 658).  I am using skin tone as a rough measure of the degree of European ancestry:

Tones 6-10, especially 10, have lower average IQs than tones 1-5.  The difference between level 1 (IQ = 93.6) and level 10 (IQ = 86.4) is well over half a standard deviation.

So blacks with more European ancestry tend to have higher IQs. The explanation that light-skinned blacks receive better treatment than dark blacks is unconvincing.  When someone of another race encounters a black person, you say "black person" to yourself, not "light-skinned black person."  And anyway, there's no evidence that poor treatment makes somebody dumber.  If it did, Jewish Holocaust survivors would be morons, not people with above average IQs.

Data: Moderately religious whites are the most ethnocentric

We saw in the last post that religious blacks, compared to their irreligious counterparts, say their racial identity is more important to them.  Does this pattern apply to whites?

I suspect the General Social Survey question is not interpreted the same by whites as blacks. It asks about ethnic identity, and I would guess whites are more likely to respond with something like, "Sure my Irishness is important."  Only a certain percentage probably interpret the question racially.

Anyway, here's what we get when we calculate mean ethnocentricity scores by church attendance (N = 2,167):

Being ethnocentric peaks for whites who attend 2-3 times per month.  By contrast, it bottoms out among those who never go to church AND those who go more than weekly.

Racially-minded whites often say that Christianity is a problem since it encourages color-blindism, but that only seems to be the case for the small share of highly religious people.  And the complete absence of religious activity is correlated with less ethnocentrism.  Moderate religiosity seems to go hand-in-hand with ethnic loyalty. 

By the way, the difference between the top and bottom group is roughly 40% of standard deviation, so it's a moderate-size gap.

NOTE: Notice how I tend to handle these topics as a scholar should, while actual scholars do not.  I use fairly neutral terms like "ethnocentric" for both blacks and whites, while elite scholars use terms like "black pride" and "racial self-esteem" for blacks, and when the same question is analyzed for whites, terms like "hatred, "racism," "white supremacism," and "hate groups" are used. These "scholars" are frauds and should be ashamed of themselves.

Data: Black conservatives are MORE ethnocentric

If you didn't know better, you might assume that blacks who are conservative or religious might be less race conscious than their black counterparts.  You might assume that religion and conservatism might nudge blacks toward the ideal of color blindness, or that loyalty to one group might reduce loyalty to another.  Wrong.

The General Social Survey asked blacks on a scale from 1 to 4 how important their ethnicity was to their sense of who they are.  Here is a graph showing means scores of this question by political orientation:

While ethnocentrism does not rise smoothly with conservatism, blacks who describe themselves as extremely conservative are the most black-centric group.  So don't think that a black right-winger wants to forget about race.

Let's look a ethnocentrism by church attendance:

The effect is not strong, but there is a tendency for more religious blacks to focus more on race identity, rather than the fact we are all children of God.

How do we explain this (admittedly weak) pattern?  (Keep in mind that mean ethnocentrism is so high for blacks of any category, there isn't much variation to explain.) Perhaps it's due to a liberal tendency to see oneself as a citizen of the world, while conservatives might be more comfortable with local loyalties. 

Data: What predicts skepticism about God best--scientific knowledge, IQ, or education?

Many 19th century thinkers believed that religion would gradually wither away as industrialization and scientific knowledge spread.  Religious belief has proven to be more stubborn than they thought, perhaps because they didn't realize that it has a genetic component, but how much of an antagonism do we see nowadays between science and belief?

The General Social Survey (GSS) asks people how much confidence they have in the existence of God with answers ranging from "don't believe" to "know there is a God."  The survey also asked ten questions that tap scientific knowledge.  I added up the correct answers and estimated the relationship between the this and belief with OLS regression (N = 4,542), and the unstandardied coefficient is -.195.  Standardized is -.265.  In plain English, scientific knowledge predicts skepticism with some accuracy.

Is this link due simply to IQ?  In other words, do smart people seek out scientific knowledge and at the same time come to look on the existence of God with skepticism?  The answer is, not really. When I add IQ to the model, it does significantly predict skepticism, but the effect is weak (beta = -.051) and the coefficient for scientific knowledge only drops a little from -.195 to -.187. 

How about education? People learn more science as they get educated, and perhaps school teaches skepticism about God. When I add years of education to the model, it is related to more skepticism only weakly (beta = -.052), and the science coefficient only drops from -.187 to -.178.  By the way, the effect of IQ on skepticism falls to non-significance with the addition of education to the model.  In other words, IQ is unrelated to skepticism when you take educational level into account. 

So, when you consider knowledge of science, IQ, and education, the factor that really seems to matter for belief is science.  (Of course, causal direction is not clear here. Religious people may tend to stay away from science since they sense it is antagonistic to their beliefs.)

Data: Educated immigrants ain't impressive

In a recent tweet, Ann Coulter claimed that H-1B visa holders are not highly skilled like President Trump says but are simply slave labor.

While I can't use GSS data to identify this group of workers, let's look at the vocabulary test scores of immigrants with at least 16 years of total education. I won't call it IQ scores since English is a second language for most immigrants, but I will argue that an immigrant's English vocabulary says something meaningful about him.

Here are the mean vocabulary scores by decade (N = 725):

Mean vocabulary (using an IQ scale)

1970s  109.5
1980s    98.7
1990s  100.9
2000s    97.6
2010s  100.7

We can see that while educated immigrants in the 1970s had good vocabularies, they dropped to the average white score by the 80s, and it has remained in that area since.

This pattern is similar to what we have seen with immigrants in general, and Americans admitted to college or graduate school: mean scores were quite good in the 1970s, but the US then got more egalitarian and lowered standards. Now we take anyone into the country or into the university.  This shows that our elites no longer put a premium on quality, but really care about giving goodies (American citizenship, access to universities) to any schmuck who shows up. 

UPDATE: If we divide the educated immigrants from this past decade by race, the mean scores are: white 104.5, black 99.5, other 96.6.

Data: Nonwhite IQ is falling

If you believe that people basically can't be changed and children are like their parents, you should be concerned with the kinds of people who are coming into the US with plans to stay here for good.

The picture does not look good when we focus on IQ.  I typically use a vocabulary test given to participants of the bi-annual General Social Survey.  One problem with this measure is that it is biased against people who weren't raised speaking English.  For this blog post, let's focus on non-whites who also not black as a rough way to capture people born in this country whose family came to the U.S. in recent decades. It's crude (for example, American Indians get included), but we do what we can. Here is the mean IQ for this group listed by decade:

Mean IQ for nonwhites (blacks excluded, N = 764)

1980s  88.4
1990s  93.0
2000s  94.0
2010s  92.4

(If you're familiar with the GSS, you know surveys were conducted in the 70s, but not enough native-born non-whites were surveyed to be included.)  Mean IQ improved for this group for 30 years (80s, 90s, 00s) but that has reversed in this decade.

This is consistent with most of the IQ trends I've looked at recently. This past decade has seen a downturn for every group I've looked at (all whites, English/Welsh, German, Italian, Mexican, East Asian) except for blacks and the Irish.

The cause of the fall in IQ is, I imagine, different for different groups, and I assume that the drop for non-whites (excluding blacks) is due to changes in the mix of immigrants.  Whatever the reasons, most trends do not look good for America. 

Despite what Nassim Taleb thinks, average IQ predicts quite well how a country performs, and the US seems headed for mediocrity.  This, of course, could be reversed if we were picky about who gets to come to America, and if intelligent citizens had more babies, while dull ones had fewer.

Data: A big drop in IQs for East Asians in the US

As I sit in this McDonald's being served coffee by a middle-aged Filipino man, I'm wondering how East Asian IQ is doing in the US.  Here is a graph showing trends since the 1970s (GSS data, US born, N = 107):

Wow, that's a significant drop. In the 1970s, the mean was 108.6.  By the 1990s, it fell to 99.3.  After an increase to 101.7 in the 2000s, it fell again to a low of 99.0 in this decade. 

I assume this drop is due to the increase of southeast Asians (e.g., Filipinos, Vietnamese) -- groups that have lower average IQs than NE Asians (i.e., Japanese, Chinese, Koreans).

Data: The four point Flynn Effect among US blacks (but pay no attention because Taleb says IQ is crap)

According to General Social Survey (GSS) data, both whites and Mexican Americans born in the US have experienced mean IQ drops in the past decade.  Is this also true of blacks?  Here are the means by decade (N = 3,865):

Mean IQ

1970s  88.0
1980s  89.0
1990s  90.8
2000s  92.1
2010s  92.4

The 70s/80s increase was 1 point; the 80s/90s was up 1.8 points; and it was up 1.3 points for the 90s/00s.  The past decade witnessed the smallest increase of 0.3 IQ points.  The 1970s-2000s gain is impressive, but lately things seem to be slowing down.

I don't how to explain the trend but suspect that American society might expose blacks and whites (via schools, mass media, etc.) to more similar words used to test vocabularies than in the past.

The typical IQ mean you read about for black Americans is 85, but the black/white verbal IQ gap appears to be smaller: GSS data indicates that in this decade the gap is six-tenths of a standard deviation.  Notice how the black mean is a point higher than the 91.5 mean for Mex-Ams reported in a recent post.       

Data: Average IQ of whites fell one-half point over the past decade

In the last post, we saw saw that Mexican Americans born in the US had a mean IQ that rose from the 1980s to the 2000s, but reversed course since then.  It is currently 91.5. 

That made me curious about other American groups.  Let's start with all whites over the past four decades (GSS Wordsum measure, N = 20, 482):

Mean IQ for whites

1970s    99.2
1980s    99.3 
1990s  100.4
2000s  101.1
2010s  100.6

As we saw with Mex-Ams, whites peaked in the 2000s, but then IQ's dropped in the past decade -- one-half a point.

This is consistent with Greg Cochran's claim that the US is undergoing rapid change in genetic potential for IQ due to intelligent people having fewer offspring.  It might be decreasing one point per generation.

Data: A negative Flynn Effect among Mexican Americans

About a decade ago, I documented an impressive rise in the mean IQ of Mexican-Americans born in the US.  Using GSS data, what is the trend in this decade?  Look at the graph (N = 609):

The mean was only 85.0 in the 1970s and 84.7 in the 1980s, but it rose all the way to 94.7 by the 2000s.  From this trend, one might get the hope that Mex-Ams might someday converge with the white average of 100.

But it was not to be. The trend has reversed in this decade, and the mean has fallen back down to 91.5.

I don't know how we explain these trends. Dysgenic trends would manifest themselves slowly.  We have seen a recent downward turn among several European populations.

The samples sizes for each decade are not large (this decade included 217 people) so some of the trend might be noise.

Assuming the 91.5 average is more or less correct, this is a bad sign for America.  A person with an IQ in the low 90s will be unable to do many of the jobs that we need done.  Such a population will have more social problems and little high-level achievement.

UPDATE:  I looked at all Americans born in the US (N = 25,116) and found a seven-tenths of a point drop in IQ from the last decade to this one.