Sunday, March 22, 2020

Study: Does a strong ethnic identity make whites happier?

The General Social Survey asked respondents, "When you think about yourself, how important is your ethnic group membership to your sense of who you are? Answers ranged from very important (4) to not important at all (1).  They were also asked about how generally happy they are these days with answers ranging from very happy (3) to not too happy (1). Here are the means for happiness listed by level of ethnic identification (sample size = 1,087):

Mean happiness

How important is your ethnicity?
Very   2.28
Moderate   2.23
Slightly   2.17
Not at all   2.17

On average, whites who are more ethnocentric are happier. The effect is statistically significant but small (around a one-fifth of a standard deviation between the extreme categories). 

It seems to me that ethnic or racial pride is a form of self-esteem, and feeling good about oneself promotes happiness. 

Saturday, March 21, 2020

What explains the tremendous cross-national variation in religious devotion? IQ? Race?

If you're like me, you could use a break from all the coronavirus, stuff, so let's focus for a moment on race, IQ, and religion. The 2010-2014 World Values Survey asked 88,042 around the world whether they were religious, not religious, or atheist. Here are the percentages listed by country who answered that they were religious:

Percent religious

Pakistan    99.7
Georgia   97.1
Ghana   97.0
Nigeria   95.9
Rwanda   95.9
Qatar   93.8
South Africa   90.7
Haiti  90.3 
India  88.8
Armenia  88.5
Yemen   86.3
Poland   86.2
Turkey   83.5
Colombia  82.5
Morocco   82.4
Peru   81.5
Romania  81.4
Philippines   80.7
South Africa  80.0
Brazil  79.7
Trinidad and Tobago  78.8
Cyprus   78.3
Iraq   76.8
Algeria   74.2
Mexico   74.2
Azerbaijan  73.2
Palestine  72.4
Ecuador   71.1
Libya   68.5
Ukraine   68.3
Argentina   67.8
USA   67.0

Total Sample  66.7

Tunisia   65.1
Slovenia   64.2
Lebanon   63.6
Belarus   62.2
Kazakhstan   61.7
Malaysia   53.7
Russia   53.1
Singapore   53.1
Uruguay   50.8
Chile   50.3
Germany   49.5
Uzbekistan   48.7
Netherlands    43.8
Taiwan   43.3
Netherlands   43.8
New Zealand   42.7
Spain   40.0
Thailand   32.0
Sweden   31.2
Estonia   30.9
Japan   20.9
Hong Kong  19.8
China  12.5

First, the world is quite religious: two-thirds of the total sample described themselves this way. On the other hand, there is tremendous variation. Almost all Pakistanis are religious, while few Chinese are.

On the issue of race, noticeable patterns emerge. South Asians and blacks tend to be very religious, and while the numbers here suggest Islam is associated with greater religiosity, countries like India, Ghana, and Rwanda show that South Asians and blacks do not need to be Muslim to be highly religious. The least religious country with lots of blacks is Trinidad and Tobago, but it is still well above average.

On the other end, East Asians are typically secular. China is at the bottom with 12.5% religious. Filipinos are the exception. This raises the importance of IQ in explaining religiosity. Depending on the estimate, mean IQ for the Philippines is between 74 and 86, and research clearly shows that lower IQ people tend to be more devout.

Europeans vary a lot with levels from 97.1% in Georgia down to 30.9% in Estonia.  Historical factors are important, but a virtue of focusing on IQ is that it helps simplify the world--a major goal of science. Estonians, for example, have a mean IQ of around 100, while it is in the low to mid-90s in Georgia.

Muslim-dominated societies vary quite a bit, too, from 99.7% religious (Pakistan) to 48.7% (Uzbekistan). IQ appears to be a little higher in Uzbekistan. Malaysia, another somewhat secular,  Muslim-dominated country (53.7% religious) has a mean IQ somewhere in the low-to-mid 90s. Overall, Muslim countries are religious.

Latin Americans countries are also fairly devout. On the high end, 82.5% of Colombians are religious, and on the low end, 50.3% of Chileans. Again, IQ might help explain the pattern: it's in the high 80s in Chile, but the low 80s in Colombia.

It looks like any association between race, ethnicity and religious devotion is, in large part, simply a reflection of differences in IQ.  The simple three-race categorization works very well: blacks (low IQ/high religiosity), whites (medium IQ/medium religiosity), and East Asians (not Filipinos) (high IQ/low religiosity). We could add South Asians as well (low IQ/high religiosity).

Wednesday, March 11, 2020

New Italian study: Men, on average, have higher levels of perceptual reasoning and working memory

A new Italian study led by a female researcher and published by the flagship journal Intelligence reports that men, on average, have higher levels of perceptual reasoning and working memory.

Perceptual reasoning refers to mental operations used to analyze novel problems, rules, and logical relationships, and to create and test solutions. By working memory, researchers mean storing, focusing attention on, and manipulating information for a relatively short period of time.

The researchers are concerned with sex differences in subtest scores that could be due to test bias or social ways that the sexes might differ, and not due to differences in general ability (that are presumably due to biological factors).

They reasoned that if subtest scores are due to broad abilities, the size of the sex difference for the subtest should correspond to the factor loading on the broad ability. For example, if the sex difference on the arithmetic is large, the sex difference on working memory (i.e., a higher-order ability) should also be large. If the latter is small but the former is larger, the authors contend that there is bias in the arithmetic test.

While authors find evidence of some bias in the WAIS-R test, they conclude that the WAIS-IV is "quite fair." If we focus on the results from the WAIS-IV data, we find that men have a small advantage in perceptual reasoning and a moderate advantage in working memory (3 IQ points).

By contrast, there are no significant sex differences in verbal reasoning or processing speed. (Some studies have found a female advantage in processing speed). When indices are combined to created a full-scale IQ score, men have a small advantage--perhaps 1 or 2 IQ points. And, according to the authors, these differences are due to broader abilities, not various forms of bias.

UPDATE: An interesting sidenote: When analyzing WAIS-IV, the researchers look at the sex differences for 15 subtests. You might expect that if there is unintentional test bias, men would come out ahead in some tests, while women might in others. But in zero of the 15 tests do women have a statistically significant advantage.

Thursday, March 05, 2020

New research finds cortical differences between seriously antisocial individuals and controls

In this new study, structural MRI data were collected on 672 45-year-old participants in the Dunedin Study, a population-representative longitudinal cohort. Twelve percent were classified as having life-course persistent (LCP) antisocial behavior, while 23% were categorized as having adolescent-limited (AL) antisocial behavior. 

These are classifications developed by criminologist Terrie Moffitt back in the 90s who hypothesized that the LCP pattern is characterized by genetically-rooted, neurological deficits, while the AL pattern is explained more by social factors experienced during adolescence.

The authors found that the LCP group, compared to the low antisocial behavior group, had a significantly smaller mean global surface cortical area and lower mean cortical thickness. The effect sizes were of moderate size for the cortical area and of smaller magnitude for the cortical thickness.

The cortical measures for the AL group were not significantly different than those for the low antisocial group.

The authors concluded that the results for both the LCP and AL groups were consistent with Moffitt's theory of antisocial behavior.

Do intelligent Mormons and Muslims have more kids than their less intelligent counterparts?

Mormons and Muslims are two groups that tend to have a lot of children. Strongly religious groups often do. Is there any chance that, unlike most Americans, their fertility patterns are eugenic? For example, do smarter individuals have more children?

The General Social Survey (GSS) asks about how many children you have had, but there are a couple problems with using this question. The sample sizes for women or adults who would be finished with having children is small, and GSS's annoying practice of putting Mormons in the "other" category forces us to rely on the question about one's religion at age 16--a question not asked of many people in the sample.

An alternative is to use the question about one's number of siblings. Since the GSS is an adult sample, most respondents will not gain any future siblings. Because the samples are still small, I've divided people into a high (7-10 answers correct on WORDSUM) or low IQ group (0-6 answers correct).

Mean number of siblings

Mormons (n = 44)

High IQ   3.63
Low IQ    4.05

Muslims (n = 73)

High IQ   4.05
Low IQ    5.04

Both religions have large families, but the lower IQ groups average more siblings. So even for groups known for their fertility, the trend is dysgenic: compared to the unintelligent, the intelligent devote more of their energy to careers, money, etc., than to having kids. Over the very long term, these groups are getting genetically dumber. Just like everyone else.

Sunday, March 01, 2020

If IQ were skin color, how visible would the racial gap be?

I often describe the differences between groups in terms of standard deviations or Cohen's d, but maybe we can get a clearer picture of what these mean with a black-and-white example; namely, skin tone.

Skin color is a very noticeable racial difference and tends to dominate discussions of race even though it is just one characteristic. People focus on it because it is obvious, and I suspect race deniers like it because they can treat it as something superficial, something only shallow people would focus on. People like Dinesh D'Souza who I often agree with will say idiotic things like race is nothing but a "coat of paint." Never mind that skin is our largest organ and carries out many important functions, and that skin color appears to have important functions as well. And anyone who claims that aesthetics aren't important doesn't know human nature.

Anyway, General Social Survey interviewers were asked to rate the skin tone of respondents with a number ranging from 1 (lightest) to 10 (darkest). The lightest ethnic group is Americans of Danish descent with a mean of 1.33. (I'm weird because I'm all NW European and 1/8th Danish but look like an Arab). We'll use Danes as the comparison group. What I show below is the gap between the Danish mean and the mean for the focal group in terms of standard deviations:

Degree to which group is darker than Danish Americans (in sd units)

Blacks  2.2
West Indians  2.2
Asian Indians  1.3
Mexicans  0.8
Filipinos  0.8
American Indians  0.8
Puerto Ricans  0.7
Chinese   0.6
Japanese   0.6

Total Sample  0.6

Spanish   0.5
Arabs   0.5
Jews  0.3
Portuguese  0.2
Italians  0.2
Greeks  0.2

A gap of 2.2 standard deviations between Danes and blacks is so huge, it's the reason why people decided long ago to define groups as the opposite of each other: black and white. If a study reports a 2 sd gap, be impressed.

Another way of describing the gap goes like this: not a single black in the sample is lighter-skinned than any Dane, and 97% of Danes are lighter than 94.5% of blacks.

If you want a visual that matches the size of the black/white IQ gap (1 sd), think of the color gap between Danes and a typical Mexican and typical Asian Indian blended together--a very large difference. Another way of saying this is that the black/white IQ gap is only half the size of the color gap.

Even a difference that is only 10% of the black/Dane gap is still visually easy to detect: the Italian and Greek means are 0.2 standard deviations darker than Danes--0.2 considered a very small difference--but southern Europeans are known for being darker than northern Europeans. The higher Spanish mean is probably due to darker Hispanics claiming Spain as their homeland.

Which low IQ groups have low arrest rates?

DGo (@Go321) on Twitter wondered which lower IQ groups still manage to be well-behaved as groups. Criminality is a decent measure of behavio...