Sunday, September 27, 2009

English Americans are most introverted, Jewish Americans are least: Here are mean introversion scores for various white American groups:

Mean introversion score (N = more than 20,000)

English/Welsh 14.2
Dutch 14.2
Swiss 14.2
Scottish 14.0

All ethnicities 14.0*

Irish 13.9*
Hungarian 13.9
Portuguese 13.9
Spain 13.9*
German 13.8*
Danish 13.7*
Rumanian 13.7
Polish 13.6*
Swedish 13.6*
Belgian 13.6
Italian 13.5*
Czech 13.5*
Russian 13.4*
Norwegian 13.4*
French 13.4*
Yugoslavian 13.4
Finnish 13.3*
Lithuanian 13.3*
Jewish 13.3*

* p < .05, two-tail test, compared with English/Welsh

The groups with asterisks are significantly more extraverted than Americans of English or Welsh descent. Here are the effect sizes for those who differ significantly:

Effect size

Irish .09
Spain .09
German .11
Danish .14
Polish .17
Swedish .17
Italian .20
Czech .20
Russian .23
Norwegian .23
French .23
Finnish .26
Lithuanian .26
Jewish .26

The differences among whites groups, even at the extremes, are small.

I checked to see if the observed pattern was influenced by immigration. I suspected that immigrants are more introverted than natives, and I was right. If we compare Jews and those of English descent born in America, the effect size increases to .37--a moderate difference.


  1. Am I missing something here, what differentiates Jews from Fins and Lithuanians?

    What about the influence of immigration on the Fins and Lithuanians....

  2. Anonymous4:54 AM

    The northern European/Germanic pattern is evident

  3. Anonymous2:22 PM


  4. I'm surprised that there isn't a direct relationship between latitude and introversion. I expected the Scandinavian countries to be the highest by a clear margin. There's a joke that says you can tell a Finn is extroverted because he is looking at YOUR feet when talking to you. Is there some sort of selection effect counterbalancing this?

  5. Odd, given that Finns are supposed to be the most introverted people around; apparently their word for 'shy' has positive connotations meaning 'strong enough to survive the cold' or something. Maybe all the extroverted Finns get fed up and come to America?

    Whatever. I've criticized my relatives for trying to diversify the country quite a few times but they seem pretty pale to me. Barking like a dog and even selling out your fellow humans to the dogs doesn't make you a dog. And I suspect if this country really does become majority nonwhite, the Uncle Tims of the world are really going to regret it. NAMs are pretty anti-Semitic. (Asians I'm not sure about...)


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