Group Size and Social Interaction: a Canada-US Comparison of Interracial Marriage

Group Size and Social Interaction: a Canada-US Comparison of Interracial Marriage (pdf)

Abstract: While black-white intermarriage is uncommon in the United States, blacks in Canada are just as likely to marry whites as to marry blacks. Asians, in contrast, are more likely to marry whites in the US than in Canada. We test the claim that high rates of interracial marriage are indicative of high levels of social integration against Peter Blau's "macrostructural" thesis that relative group size is the key to explaining differences in intermarriage rates across marriage markets. Using micro-data drawn from the American Community Survey and the Canadian Census, we demonstrate that the relative size of racial groups accounts for over two-thirds of the US-Canada difference in black-white unions and largely explains the cross-country difference in Asian-white unions. Under broadly similar social and economic conditions, a large enough difference in relative group size can become the predominant determinant of group differences in the prevalence of interracial unions.

Lifespan of the European Nobility from the Dark Ages to the Industrial Revolution

Neil Cummins summarizes his paper "Longevity and the Rise of the West: Lifespans of the European Elite, 800-1800":

European nobility specialized in the execution of violence. Their genealogies connected them to the Barbarian conquerors of Europe following the decline of the Roman Empire. A large proportion of noble men died in battle. To investigate precisely how many nobles died from violence, I employed a general version of the famous birthday problem. First year statistics students are often introduced to probability via the surprisingly low number of people it takes to have a high probability of a shared birthday. If we take the number of exact-date deaths per year, n, and the number of deaths on a given day, m, we can calculate the probability that a given n-m combination occurs randomly or is likely the result of a battle. I use this ‘clumping’ technique to estimate the proportion of nobles dying from violence. My estimates are presented in figure 1 below. Violence suddenly declines within this warrior caste in the 16th century. [. . .]

Nobles live significantly shorter lives in the South and East relative to the North and West. My analysis indicates that this Mortality pattern has existed since 1000AD.

These results have implications for theories of the rise of Europe. The European Mortality Pattern revealed above correlates with those regions which later experience the Industrial Revolution first. Recent research has suggested that “The Great Divergence” of East and West is preceded by a little divergence of East and West, within Europe, around the time of the Black Death (1347). This research shows that North-West Europe was differentiated from the rest of the continent by its demographics centuries before the Black Death.

A new set of stylised facts has been uncovered that seem to raise more questions than they answer. Why were noble lifespans longer in Northwest Europe in 1000AD? What caused noble lifespan to shoot upwards in 1400? Why did violence decline so suddenly in the 16th century? Future research will tell us more.

From the paper:

ABSTRACT I analyze the age at death of 121,524 European nobles from 800 to 1800. Longevity began increasing long before 1800 and the Industrial Revolution, with marked increases around 1400 and again around 1650. Declines in violence contributed to some of this increase, but the majority must reflect other changes in individual behavior. The areas of North-West Europe which later witnessed the Industrial Revolution achieved greater longevity than the rest of Europe even by 1000 AD. The data suggest that the 'Rise of the West' originates before the Black Death. [. . .]

Further, a list of the 3,133 sources will be provided in a data file on my website, neilcummins.com. Following publication, replication files and data will be provided there too. [. . .]

This study has characterized noble lifespans from 800 to 1800. The results have many implications. Firstly, the sharp decline in the proportion of male nobles dying from violence, from at least 600 years of a steady 30% to less than 5% in the 16th century, predates the arrival of the Industrial Revolution by two centuries. The long run decline in violence 25 is cited as one of the principal correlates of the emergence of the modern World. Why did violence decline among European nobility? Was it a ‘bottom-up’ behavioral change (perhaps as a result of natural selection, as Clark (2007) suggests for the general population) or was it a response to changing ‘top-down’ institutional incentives (as argued by Acemoglu and Robinson (2012))? [. . .]

Finally, this paper documents a previously unknown European mortality pattern, Sim- ilar to that for marriage first documented by Hajnal (1965), the mortality gradient runs South-North and East-West, and has existed since before the Black Death 30 . The long existence of such a geographic effect has implications for recent work which stresses the ‘little divergence’ between the North-West of Europe and the South-East (Voigtländer and Voth (2013), Broadberry (2013) and de Pleijt and van Zanden (2013)). The Black Death is not the first turning point. There was something about the North-West of Europe long before 1346 that led to nobles living longer lives.

These results suggests that the ‘Rise of the West’ does not solely originate in institutional innovations of the 17th century (Acemoglu and Robinson (2012)) nor in social reactions to the Black Death (Voigtländer and Voth (2013)). Western exceptionalism exists in individual behavior differences that are present since at least the first millennium AD.

Social Mobility among the French Noblesse in the Later Middle Ages

A few figures are here necessary. Out of the 215 lignages that appear in records at one time or another in the thirteenth century, no less than 66, or 30.7% of the total, had disappeared before 1300, the male line having become extinct. During the next century, from 1300 to 1400, the rate of disappearance seems to have remained the same, in spite of the fact that it was a time of wars and pestilences: 80 of the 149 remaining families, or 53.6% of them, became extinct in their turn. Another 38, or 55% of the remaining 69, disappeared between 1400 and 1500. The process went on with the flow of time. By the time of the French Revolution no more than five of these 215 lines were still alive. Two of them remain to this day, if we rule out a third one which descends from a bastard branch but which managed to be maintained in its noble status by a decision of Louis XIV.15 From these figures it might be said that, roughly speaking, the nobility loses half its members within any given century. The average duration of a noble line is hardly more than three or four generations; let us say, to be on the safe side and to take account of the hazards of the records, between three and six generations, stretching from one to two centuries. This tallies with the findings of Mr. Sanders, who, analysing the descent of some 210 baronies from the Conquest to 1327, has shown (or rather I have worked out the figure from his catalogue) that only 36 of them remained more than two centuries in the hands of the same male line.16 English baronies, however, were partible between heiresses even when junior branches still possessed male members, so that the figures are not entirely comparable.

It must be pointed out here that this high rate of family-mortality bore no relation to the economic status of these lignages. Death strikes equally rich and poor, baron and squire, the eminent and the insignificant. Causes general to the times were at work: high mortality in spite of a high birth-rate; the hazards of war; those of political upheavals, with their train of attainders and confiscations - which, at least up to the fourteenth century, were less important in France than in England. Other causes are particular to such social groups as attain some sort of eminence. Thus, the necessity, in order to avoid splitting estates through partition between children, of sending younger sons into the Church, would sooner or later bring the line to an untimely end. [. . .]

New families were thus constantly replacing the dying ones. Some of the newcomers came from junior branches of the local nobility itself, who, through marriage with heiresses, replaced in their lordships the old lines now extinct.'9 Others belonged to the gentry of neighbouring provinces and settled in Forez in the same way.20 None of these was really bringing new blood into an otherwise dwindling social class. More important for our purpose are the new men, those who suddenly appeared as knights or squires with no known ancestry in the nobility and who, given the chance, founded new noble lignages. To know where they came from, we must work mostly by inference and generalise from a few well-documented cases. We can be sure, however, that these newcomers were not recruited from a well-defined social group, but came from widely different strata [. . .]

In a country and at a time when society was almost entirely rural, the largest group of new noblemen came, so it seems, from peasant- stock. In Forez, there was no sharp dividing line between peasants and poor squires, except their different birth. By the thirteenth century, serfdom was as unknown there as in Normandy; all peasants were freemen, even those who owed tallage and a few labour service restricted to one or two days a year.

[Edouard Perroy. Social Mobility among the French Noblesse in the Later Middle Ages]

R. A. Fisher: The Social Selection of Fertility (1930)

Chapter 11 of The Genetical Theory Of Natural Selection:

"fertility may be a strategic choice for ethnic groups engaged in redistributive conflict"

The political economy of fertility (draft pdf):

This paper studies the political economy of fertility. I particularly ask whether fertility may be a strategic choice for ethnic groups engaged in redistributive conflict.1 There are at least two reasons why the answer could be affirmative. First, individuals in diverse societies tend to vote for co-ethnic political candidates, who then reward them with transfers, jobs, or local public goods (Young 1976, Bates 1981). Fertility should therefore increase an ethnic group’s voting power and gains from political office. Second, if ethnic groups allocate society’s resources via conflict or bargaining in the shadow of conflict (Horowitz 2000, Collier and Hoeffler 2004), then fertility might increase their combat strength.2 Importantly, however, these redistributive gains to fertility should mainly be present where weak institutions erode the security of property rights.

To further explore these issues, this paper presents a simple model of redistributive ethnic conflict with endogenous fertility. I then test the model in a cross-national dataset. Consistent with the theory, I find that economies with high ethnic diversity and/or weak institutions have higher fertility rates. I conclude that high fertility may have political roots.

Frank Salter on multiculturalism

Multiculturalism in the life of a society 7

Advice for women and men

Some woman: "In the end, infertility can make you feel less human. As cultivated as we are, we hold on to a deep-rooted belief that our worth is tied to how well, and how much, we reproduce. I've seen women and men shrink like salted slugs during IVF treatment. [. . .] Many women are still listening to their bosses instead of their gynecologists and their guts. They still trust that their mid to late 30s is a fine time to start trying for children. True, they could get lucky. But the question should be asked: Would you prefer to have children earlier and naturally or later, by dosing yourself up with drugs, submitting to surgery and paying tens of thousands of dollars? [. . .] The first thing I'd like to tell women ages 26 to 34 is: Start having babies. I know it's not polite or funny. But I don't want others to go through what I'm going through now." (Holly Finn; My Fertility Crisis; We hear about fertility treatments when they're successful. But for millions of women, they mean regret, heartbreak, shame and silence.)

Winston Churchill: "There is no finer investment for any community than putting milk into babies" - radio broadcast, 1943. "You must have four children. One for Mother, one for Father, one for Accidents, one for Increase".

Julian Huxley: "If we want to maintain the race, at a high level, physically and mentally, everybody sound in body and mind should marry and have enough children to perpetuate their stock and carry on the race."

X chromosomes and human demographic history

Amanda M Casto et al. Characterization of X-Linked SNP genotypic variation in globally-distributed human populations. Genome Biology 2010, 11:R10doi:10.1186/gb-2010-11-1-r10

We have explored the possible impacts of both demography and selection on X-linked genetic variation. With regards to the former, we were particularly interested in investigating the possibility of male versus female demographic differences as these can be detected by comparing autosomal and X-linked data. Previous studies have found evidence for skewed gender ratios. Indeed, here we showed that evidence for asymmetries in both directions (male Ne/ female Ne less than or greater than one) can be found within a single dataset. Our results suggest that the picture of male versus female demography is complex and that each study addressing this question should be viewed as providing insight on a particular geographical scale and period in history rather than an absolute answer.

Natality data / rates of cross-racial breeding

Lenny asked for statistics on interbreeding (as opposed to just intermarriage/dating). Based on my analysis of the 2005 Natality Detail File [1]:

Of 2280259 children born to Non-Hispanic White women, the racial breakdown of fathers is roughly:
89.23% Non-Hispanic White
5.46% Hispanic
3.18% Non-Hispanic Black
2.13% Non-Hispanic Other Races

Of approximately 2217946 children fathered by Non-Hispanic White men, the racial breakdown of mothers is around:
92.76% Non-Hispanic White
4.12% Hispanic
0.96% Non-Hispanic Black
2.17% Non-Hispanic Other Races

These numbers are not inconsistent with the facts in my previous post: lower-quality women, who are more likely to engage in miscegenation, also unfortunately account for a disproportionate share of births [2].

For white mothers with Bachelor's degrees or above, the father is white in 94+% of cases. For married white mothers, the father is white 93% of the time. The educational breakdown of white mothers of white children vs. white mothers of mulatto children:

Less than HS: 9.1% vs. 19%
HS grad. or GED: 23.5% vs. 35.5%
Some college: 21.1% vs. 24.6%
Associate degree: 9.6% vs. 7.2%
Bachelor's degree or above: 36.3% vs. 13.1%

Education levels of white women who breed with Hispanics are similar to those of white women who mate with blacks.

So, on a positive note, while interbreeding will contribute to a reduction in the number of whites in America, it may slow the dysgenic decline of the whites who remain.


[1] "The public-use Natality Detail Files include all births occurring within the United States. Births occurring to United States citizens outside the United States are not part of these files. Data are obtained from certificates filed for births occurring in each state."

2005 is the most recent year for which this data is available. Race of father is "unknown or unstated" for about 9.6% of births to white mothers (the fraction is larger for most other groups). In the overwhelming majority of cases, when the race of the father is unknown or unstated, the mother is unmarried. My estimates assume the racial breakdown of fathers in these cases follows that for unmarried mothers of a given race where race of father is reported. Since about 10% of white mothers where the race of the father is not reported are married, and because I have ignored the (small number of) mothers with race unknown or unstated, the numbers I post above probably slightly overstate rates of interbreeding for white women and understate numbers for white men.

[2] E.g.:

In a 1988 study, Retherford and Sewell examined the association between the measured intelligence and fertility of over 9,000 high school graduates in Wisconsin in 1957, and confirmed the inverse relationship between IQ and fertility for both sexes, but much more so for females.[9]

In a 1999 study Richard Lynn examined the relationship between the intelligence of adults aged 40 and above and their numbers of children and their siblings. Data were collected from the 1994 National Opinion Research Center survey among a representative sample of 2992 English-speaking individuals aged 18 years. Findings revealed that weak negative correlations of -0.05 and -0.09, respectively were found. Further analysis showed that the negative correlation was present only in females.

Also likely contributing to the lower interbreeding rate by white men: the U.S. Hispanic population contains significantly fewer females than males.

# Sex Ratio (Males per 100 Females) in 2000
* Latino Foreign-Born (113)/Native-Born (100)
* Mex. Foreign-Born (126)/Native-Born (102)
* U.S. Population (96)
* U.S. Non-Latino White (96)

How 4.5 million Irish immigrants became 40 million Irish Americans

This paper tends to support my and others' belief that English ancestry is massively underreported in the US Census.

AMERICAN SOCIOLOGICAL REVIEW, 1994 Feb;59(1):64-82.

How 4.5 million Irish immigrants became 40 million Irish Americans: demographic and subjective aspects of the ethnic composition of white Americans.

Hout M and Goldstein JR

How did 4.5 million Irish immigrants come to be 40 million Irish Americans? The growth of ethnic populations, including the Irish, has three components: natural increase, intermarriage, and preference. We combine a demographic analysis of natural increase with a sociological analysis of intermarriage. Preference is a subjective component; it remains a residual in our analysis. [p. 65]

Intermarriage and its complement, homogamy, are generally assumed to be critical factors in whether national origin groups grow or decline. Generations of "pure" Irish, Italians, Poles, and so on, have admonished their children to marry within the group to preserve it. However, recent findings by Alba (1990) and Waters (1990) imply that intermarriage hurts some groups but helps others, at least in the numerical sense. In the world of ethnic options, intermarriage provides an opportunity to exercise one's options. For some ethnic groups, intermarriage thins out the ethnic heritage because few offspring of mixed marriages remember ancestors from that group. For other groups, intermarriage is a recruitment opportunity because the offspring of mixed marriages often think of themselves as part of that group, simplifying their mixed heritage with a single mention or expressing the sense that they "feel closer" to one group than to the other.

Formally, we could show that if all groups have the same intermarriage rates and if the patterns of intermarriage between each pair of groups is symmetrical, then intermarriage will have no effect on the size of th population identifying with a group. However, there would be no point in such a formal exercise because neither premise is true. Intermarriage differs significantly among ethnic groups (Alba 1976; Lieberson and Waters 1988). The groups that started coming to North America first now have higher rates of intermarriage than groups that have come in large numbers more recently have had. This has led some observers of ethnicity to include intermarriage as a condition of assimilation (Gordon 1964). Geographically dispersed groups are also more likely to intermarry than are isolated or concentrated groups (Peach 1974; Lieberson and Waters 1988). [pp. 70-71]

CONCLUSION

Natural increase of a population is the interaction of demographic trends with the elapsed time between immigration and the present. Social increase stems from the joint effects of a high rate of intermarriage and the high probability that someone will express a particular ethnic attachment. For example, the social increase of the Irish and German populations in America has far outstripped their natural increase. This important subjective component of ethnic identity is beyond our data; we can only speculate on its sources and implications. Second- and third-generation Americans, especially those of mixed heritage, exercise a significant level of choice in defining their ethnicity (Alba 1990; Waters 1990; Farley 1991). This has led to a certain unreliability in responses to ethnicity questions (Waters 1987; Farley 1991) and an alleged shallowness in the ethnic attachments reported to the Census. Our analysis has shown how the numbers of people identify with two groups -- the Germans and the Irish -- have increased because of this process. We have also shown how religious homogamy and the religious diversity of the Germans and the Irish combine to produce an intermarriage pattern that abets German and Irish ethnic identification, and how intermarriage has hurt identification with another outmarrying group, the British. We have also shown how numbers identifying themselves as Italian have grown, despite religious homogeneity, because of ethnic homogamy. We will not be surprised if the various Hispanic groups follow the Italian pattern in years to come.

Ethnic intermarriage is limited by religious homogamy and social homogamy. Groups that are affiliated with the same religion, have similar socioeconomic status, and live in the same parts of the country have much higher intermarriage than groups that differ in religion, education, and region. A past history of intermarriage and American residence are also important; groups with many mixed attachments and few foreign-born members intermarry more. The nine-fold increase of the Irish population in the United States stems from the combination of favorable outcomes on each of these variables for the Irish. The Irish have been in the United States a long time; they are religiously diverse, highly educated, and dispersed throughout the country. In addition, an unexplained subjective "closeness" to Ireland contributed to the size of the Irish American population in 1980. [p. 79]

What's to explain? Identify as Irish and you get to be a colorful victim, diametrically opposed to the evil, dull WASP television and public schools have taught you to hate.

Aside from that effect, British-Irish and British-German mixes may simply be more aware of the origins of their more recent immigrant ancestors.

"Disappearing" Smiths

The desis are baffled:

Statistical Modeling, Causal Inference, and Social Science asks where asks where all the Smiths have gone:

Sam Roberts writes,

In 1984, according to the Social Security Administration, nearly 3.4 million Smiths lived in the United States. In 1990, the census counted 2.5 million. By 2000, the Smith population had declined to fewer than 2.4 million.

Where did all the Smiths go from 1984 to 1990? I can believe it flatlined after 1990, but it's hard to believe that the count could have changed so much in 6 years.

Perhaps it's the difference between the SSA and Census methods of counting

Here's another explanation, it's the inverse of the phenomenon of those claiming Native American ancestry in the United States doubling in 10 years. Many Smiths were at one point Schmidts, who knows if some of them didn't revert now that WASP surnames aren't as value-added?

Naturally, Newamul Khan is hilariously off base. The Columbia blogger was on the right track. Nathaniel Weyl discusses the SSA data in The Geography of American Achievement:

. . . a little known publication of the Department of Health and Human Services entitled Report of Distribution of Surnames in the Social Security Number File September 1, 1984. This covers all surnames of persons who have been enrolled with Social Security from the inception of the program in 1936 to the date of the report. Total coverage is 346,417,726, or considerably more than the total 1984 poulation of the United States, which was approximately 237 million. The excess is due primarily to deaths and name-changes caused by marriage. [p. 9]

So, there were approximately 2.33 million Smiths living in the US in 1984 [(3.4/346.4)*237], in line with the 2.5 million Smiths in 1990. No mystery exists. That's not to say we don't have problems. From the original NYT story:

The number of Hispanics living in the United States grew by 58 percent in the 1990s to nearly 13 percent of the total population, and cracking the list of top 10 names suggests just how pervasively the Latino migration has permeated everyday American culture.

Garcia moved to No. 8 in 2000, up from No. 18, and Rodriguez jumped to No. 9 from 22nd place. The number of Hispanic surnames among the top 25 doubled, to 6.

Compiling the rankings is a cumbersome task, in part because of confidentiality and accuracy issues, according to the Census Bureau, and it is only the second time it has prepared such a list. While the historical record is sketchy, several demographers said it was probably the first time that any non-Anglo name was among the 10 most common in the nation. “It’s difficult to say, but it’s probably likely,” said Robert A. Kominski, assistant chief of social characteristics for the census.

Luis Padilla, 48, a banker who has lived in Miami since he arrived from Colombia 14 years ago, greeted the ascendance of Hispanic surnames enthusiastically.

“It shows we’re getting stronger,” Mr. Padilla said. “If there’s that many of us to outnumber the Anglo names, it’s a great thing.”