HVGIQ: Puerto Rico

The Commonwealth of Puerto Rico is a Spanish-speaking territory of the United States. Puerto Ricans are United States citizens—they can freely migrate between the island and the states, join the military, or even run for president. But they can’t vote for president, because the territory is not a U.S. state. In three referendums from 1967 to 1998, Puerto Rican voters rejected both political independence and U.S. statehood. However, in November 2012 a solid majority (61.3%) voted in favor of statehood. This kind of political nudging could quite possibly result in Puerto Rico becoming the 51st U.S. state … but only Congress and the president have authority over the matter, and analysts agree that approval is unlikely. This particular referendum also left off the option traditionally most favored by Puerto Ricans: continued commonwealth status. Many islanders appear to feel that statehood offers few additional benefits over citizenship; a majority of Puerto Ricans already live on the U.S. mainland (5 million vs. 3.7 million).

From the earliest days of intelligence testing, social scientists have taken a special interest in U.S. Hispanics. Proportionate to their numbers, it’s possible that more tests have been given to Hispanics than to blacks. But this special attention has also lacked focus. African-American test results have been subject to meticulous cataloging, synthesis and analysis (Shuey, 1966; Jensen, 1998; Jencks & Phillips, 1998) leading to somewhat of a consensus on the size and shape of the black-white cognitive performance gap. Yet there has not been a similar effort to process the disparate and voluminous literature on the abilities of U.S. Hispanics. Therefore there is less knowledge and consensus about the historical and contemporary test performance of Hispanic minorities.

Most of the U.S. Hispanic population is Mexican American (63%). Puerto Ricans are the second largest Hispanic minority (9.2% … or 15.3% including the Commonwealth). This post represents the first effort to comprehensively summarize the abilities of one of these two important American minority groups. Here I describe and analyze the results from over 70 studies that have measured the abilities of Puerto Ricans.

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The Onset and Development of B-W Ability Differences: Early Infancy to Age 3 (Part 1)

At what age does the cognitive ability gap between blacks and whites first appear? At what age does the black-white ability gap stop growing?

Knowing the answers to these questions is vital to understanding the etiology of the black-white ability gap, especially if this gap has an environmental cause. However, the only scholarly work that attempts to investigate these issues is John Loehlin’s Race Differences in Intelligence (1975), which is nearly 40 years old. So I will update and expand upon that review here on Human Varieties by summarizing all available measurements of African American cognitive ability from early infancy to age 3; I will also discuss the relevance of this data to current debates in the social sciences.

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HVGIQ: Bermuda

Bermuda is a tiny British Overseas Territory in the North Atlantic Ocean, some 600 miles from the East Coast of the United States (population: 64,700). Even though Bermuda is 1000 miles from the Caribbean Sea, there are a number of sociological similarities between Bermuda and the Caribbean island nations; it is an associate member of the Caribbean Community. Its economy, much like the Cayman Islands and The Bahamas, is largely based on finance and tourism, and it likewise enjoys one of the highest standards of living in the world.

According to the 2000 census, Bermuda is 54.8% black and 34.1% white. IQ and the Wealth of Nations (2002) did not include intelligence data for Bermuda, but IQ and Global Inequality (2006) reported an IQ of 90, as the average of two studies. In this post I discuss some overlooked data which suggest that Bermudian blacks have an IQ that is very close to 100, and that there is no IQ gap between black and white Bermudians. There is also some overlooked test data which suggest otherwise, and we are left with some uncertainty over the meaning of the conflicting research. Continue reading

HVGIQ: Dominican Republic

The Dominican Republic shares the island of Hispaniola with Haiti, but has a much higher standard of living. Jared Diamond offered some characteristically plausible-sounding reasons for this disparity in his 2005 book Collapse, and these ideas received a fair bit of media coverage following the Haiti earthquake in 2010. While race and human capital both played a part in those explanations, Diamond did not mention intelligence differences (having already rejected this line of thinking as “loathsome” in Guns, Germs, and Steel (1997)). However, the theoretical relevance of this variable is obvious: intelligence and achievement tests are a more direct measure of individual human capital than input variables like education. Jones and Schneider (2006) found IQ to be “the most robust human capital measure” in an expansive dataset of international comparison measures—a better predictor of economic development than variables like educational spending and enrollment.

IQ and the Wealth of Nations (2002) did not include data for either Haiti or the Dominican Republic, but Lynn’s dataset has included one study for the Dominican Republic since the publication of IQ and Global Inequality (2006).

Here I scrutinize Lynn’s use of this reference and introduce a few more small studies. The data available for the Dominican Republic is quite meager. Continue reading

Cryptic Admixture, Mixed-Race Siblings, & Social Outcomes

Charles Murray’s 2005 Commentary article, The Inequality Taboo, expressed the idea that the post genomic era has finally brought us a method to resolve the question of genes, race, and intelligence:

To the extent that genes play a role, IQ will vary by racial admixture. In the past, studies that have attempted to test this hypothesis have had no accurate way to measure the degree of admixture, and the results have been accordingly muddy. The recent advances in using genetic markers solve that problem. Take a large sample of racially diverse people, give them a good IQ test, and then use genetic markers to create a variable that no longer classifies people as ‘white’ or ‘black,’ but along a continuum. Analyze the variation in IQ scores according to that continuum. The results would be close to dispositive.

Murray believed such a project would only project scientific legitimacy if the participating researchers had diverse beliefs about the causes of the black-white IQ gap. But when he attempted to assemble the team, with assurances that he himself would find the funding, only the hereditarian researchers wanted to contribute to the project. So it did not happen.

Would the results of such a study really be close to dispositive? Yes and no. Continue reading

HVGIQ: The Bahamas

The Bahamas is one of the most prosperous nations in the world (Third highest GDP per capita in the Americas, behind the US and Canada), with an economy, much like the Cayman Islands, primarily dependent upon tourism and finance. The population, not much larger than 350,000, is 85% black, 12% white, and 3% Asian and Latin American.

IQ and the Wealth of Nations (2002) does not have a study for The Bahamas, but estimates an IQ of 78 by using the score from Barbados (p. 74). IQ and Global Inequality (2006) estimates an IQ of 84 by averaging the scores from Cuba and the Dominican Republic (p. 55), and this is the estimate still reported in the most recent book (Lynn & Vanhanen, 2012, p. 20).

Here I discuss measured IQ data for The Bahamas from two different studies. Continue reading

HVGIQ: Jamaica

IQ and the Wealth of Nations (2002) cites one study for Jamaica (Manley, 1963 ). The sample size is nearly two thousand school children, and the reported IQ is 72 (p. 209). Lynn’s various updates to that book have included five additional references. However, in another anomaly, the most recent book contains only two references, both with relatively small sample sizes, and omits the large study altogether. The IQ estimate for Jamaica has also been lowered to 67! (Lynn, 2012, p. 403)

Here I review over 20 intelligence test studies from Jamaica. I find that Lynn’s numbers were not accurately reported, and that IQ is significantly higher in Jamaica than his books have claimed. Continue reading

Gildea (1992): A lost IQ study of transracially adopted Koreans

In 2005 one of my co-bloggers at Gene Expression posted an excerpt from a Wall Street Journal article asserting that large US ethnic performance differences in spelling bees were due to dubious cultural values. My response was Is it Really Bee-cause of Culture?, which argued that cultural arguments for ethnic differences (at least in their standard formulations) are empirically false. First of all, it’s one thing to argue that “correlation does not imply causation”, but most claims about, say, Asian super-parents or black anti-intellectualism don’t even rely on real correlations, but ex post facto rationalizations: Asian parents must be amazing, because look at how well their kids perform! Research has disconfirmed many of these supposed ethnocultural advantages and disadvantages. Second, behavior geneticists have looked at full siblings, half siblings, adopted siblings, etc; even where real correlations between outcomes and home variables exist (e.g., children with high IQs come from homes with more books), these correlations are demonstrably the result of shared genetic background between parents and their biological offspring, not due to the influences of home environment. Third, and this will be my primary focus here, transracial adoption research is able to test these claims even more directly. Do people from ethnic group Y, that are raised by parents from ethnic group Z, grow up to become like people from biological group Y or from cultural group Z? Again this research has not been kind to culture theory. (“Culture”, of course, could also be transmitted through other hypothetical social influences, but it is not my intention to discuss this all in great detail right now).

Shortly after writing that post, I decided that more needed to be written about transracial adoption research as a behavior genetic experiment. Arthur Jensen, Richard Lynn, and J. Philippe Rushton have all cited the Minnesota Transracial Adoption Study, as well as several IQ studies of transracially adopted Asians, in support of the hereditarian position. And Richard Nisbett has referenced several other adoption studies that suggest no racial gaps. However, I suspected there was more data for transracially adopted children than what this small cadre of scientists had already discussed (at the very least for important variables other than intelligence); research that could give us a more complete picture of what these unusual children become, and what this can tell us about the causes of ethnic differences in socially valued outcomes.

So I spent a number of months during 2006 doing research for an E-book idea (tentatively titled Race Differences & Transracial Adoption). And there were indeed a number of novel and revealing finds in that process. Unfortunately—as usual—I could not obtain all the existing research I wanted, so I never proceeded with the project. Even worse, I never shared what I had discovered with a wider audience. Human Varieties can now serve as an appropriate platform to share those discoveries.

This post heralds the grand new epoch of sharing by summarizing an unpublished doctoral dissertation on IQ and academic achievement in a sample of transracially adopted Koreans (Gildea, 1992 ). According to Google Scholar, no one has previously cited this paper. Here be dragons! Continue reading

HVGIQ: Cayman Islands

The Cayman Islands is a British Overseas Territory. In global comparison, this tiny dependency ranks near the top in standard of living and per capita GDP (currently sandwiched between the U.S., Ireland, Japan and Iceland). Lynn and Vanhanen’s books include data for Bermuda—another Overseas Territory—but do not mention the Cayman Islands.

At least one psychologist has administered intelligence tests to Cayman Islands school children (1960 Curti ), and this forgotten study is noteworthy because it is also one of the relatively rare instances where black and white IQ scores have been compared outside of the United States, Britain, and South Africa. Continue reading

HVGIQ: Cuba

There are several intelligence studies for Cubans, including at least two Raven standardizations, some international assessment data, and a few different test measures for Cuban Americans. The message of all these test results is complicated and leaves us with a few puzzles.

IQ and the Wealth of Nations (2002) and IQ and Global Inequality (2006) both list one intelligence study for Cuba: a large Standard Progressive Matrices standardization (Alonso Garcia, 1973 ). In another anomaly, however, this reference has disappeared from the latest version of the dataset (Lynn & Vanhanen, 2012). Cuba is missing from their list of ‘National IQs’ (p. 391), and the reference is not in the bibliography. But this omission is clearly a mistake, since one table (p. 22) still features a ‘Measured IQ’ score for Cuba—85—the same score paired with this study in the previous books. Continue reading