Wednesday, December 20, 2017

New research on testosterone and behavior

A retired researcher friend asked for my help. He has been linking male sex hormones to behavior for more than three decades. Since he is retired, he has no access to students to volunteer as research participants. I can't help him because there is no way the IRB committee at my university will approve this study.  He needs volunteers to complete this 5 minute survey. Please help if you can, and invite others. We need the broadest sample we can get. Warning: you will need to measure a body part!

UPDATE: Of course, this study is very exploratory. He wants to see if it looks promising. 

Thursday, December 14, 2017

Addiction among American Indians

I ran across a new study reviewing the research on race and addiction. The authors find that: 
In these studies, both past year and lifetime rates of alcohol, nicotine, and drug use disorders were consistently higher in Native Americans and lower in Asians,with Blacks, Hispanics, and Whites in between. 
It looks like any theory of American Indians (AIs) that limits itself to alcohol (e.g., the notion that AIs have not been exposed to it long enough to adapt to it) is missing part of the story. Addiction to drugs in general tends to be more common in this population.

Also--the stark differences between Northest Asians and Natives--addiction differences being only one illustrative trait--show how quickly significant genetic change can occur (the differences surely can't be 100% due to environment). It's not like these groups split 100k years ago. 

Monday, November 20, 2017

Liberal men, sexist pigs?

I analyzed General Social Survey data a few years and showed that liberal women are more likely than conservatives to report being victims of sexual harassment. My take at the time was that liberal ideology makes women define normal sexual advances as inappropriate and abusive. But now I'm wondering if liberal women simply work around many liberal men, and liberal men simply lack the old-fashioned chivalry found more often among conservatives.

Here's a replication:

Percent reporting sexual harassment over past 5 years

Extremely liberal  23.7
Liberal  18.9
Slightly liberal  19.5 
Moderate  16.7  
Slightly conservative  19.3
Conservative  15.9
Extremely conservative  10.3

Thursday, August 17, 2017

99 genetic loci related to IQ in a sample of 280k

Recent studies of the genetics of IQ have been AMAZING. The latest--posted just today--is a sample of 280,000 subjects, and it found 99 loci (and 9,714 SNPs) significant related to IQ. Many of these loci also predict information processing speed, general cognitive function and health variables. The picture emerging is that a well-functioning, healthy brain is a smart brain, and genes are responsible for much of it.  Intelligent people, for example, are less likely to suffer from Alzheimer's.

Friday, August 11, 2017

The importance of self-discipline

The Alt-Right makes a big deal about IQ, and rightly so, but I just ran across this meta-analysis of dozens of studies that shows that the supertrait of conscientiousness--basically self-discipline--is just about as predictive of academic performance as intelligence.

Monday, August 07, 2017

Race and gang membership

I ran across this self-report study of youths in seven cities. According to my calculations, Hispanics are 3.3 times as likely to be gang members as whites. For blacks, it's 3.1 times more likely. And these estimates include a lot of wannabe gangsters, so the racial/ethnic gaps are likely to be larger among serious gang members. Not surprisingly, the researchers find that members of gangs commit a lot more crime than people not in gangs. Gangs are not just social clubs. 

Friday, August 04, 2017

Another look at ancestry and IQ

It's been a few years since I looked at verbal IQ data listed by ethnicity. It's important to look at recent data since so many immigrant groups have such small samples sizes, estimates are not very reliable. Using GSS data, here is the ranking of scores to a 10-point vocabulary quiz--a quick measure of verbal IQ. I omitted people not born in the US since the quiz is biased against non-native speakers:

Vocabulary Ranking by Ancestry

Austria   7.27
Russia    7.12 
Lithuania   7.08
Romania   6.95
Denmark   6.85 
England/Wales   6.84
Hungary    6.78
Scotland   6.75
Yugoslavia   6.73
Sweden   6.71
China   6.70
Norway   6.68 
Switzerland   6.65
Arab   6.61
Finland   6.58 
Greece   6.53
Czech   6.56
Ireland   6.46 
Poland   6.46
Japan   6.47
Italy   6.42
France   6.34
French Canadian   6.30
Germany   6.29
Belgium   6.28
West Indies   6.19
Portugal   6.18
Netherlands   5.99
Philippines   5.84
Spain   5.83
India   5.53
American Indian   5.31
Africa   5.16
Mexico   5.00
Puerto Rico 4.99

The pattern hasn't changed much since the last time I looked. What jumps out at me: 1) Mex-Ams and Puerto Ricans are still at the bottom, even lowers than blacks; 2) recent data indicates that American Muslims might assimilate better than European Muslims--the data here indicates that US Arabs are pretty smart; 3) Asian Indians (n = 40) still have a low average despite their reputation for intelligence; 4) it looks like southern Europeans don't do as well as northern Europeans (but Romania and Yugoslavia are high); and 5) central and Eastern Europeans might get a boost toward the top of the list by the large numbers of Jews (with a mean of 7.56) among their ranks.

And if you're thinking, this is just all environment, you're wrong: According to this meta-analysis, vocabulary is 62% genetic among children, and it is certainly higher than that among adults.

Oh, and if you think the differences are no biggy, again you're wrong: The gap between the top and the bottom is huge: well over 1 standard deviation.