Friday, December 19, 2008

More on perceptions of nature and nurture from the GSS

++Addition++Agnostic points out that 10, which should represent 55% genetic, 45% environmental, gets a large number of responses, even more than 11 does. This is presumably because many people incorrectly see 10 as the midway point between 1 and 21. It's impossible to completely untangle this, since 11 gets a higher response rate than other "in between" values do, indicating that nearly half of those who believe that genetic and environmental influences play an equally influential role did follow the instructions correctly (isn't that a relief?). I've redone the calculations under the presumption that both 10 and 11 indicate equal attribution to genetic and environmental influences. This underrepresents the percentage of people who assert that genes are more important, but not by much (just by the number of respondents who knew that 10 represented a 55%/45% split and chose it accordingly).

I should have suspected something was amiss because the attributions to genes and environment were too evenly split compared to responses for the question on whether genes or the environment played a major role in shaping personality. But that is what astute readers are for!


Agnostic brought four more GSS questions regarding perceptions of the influence of genes and experience to my attention. Like the question on what is perceived to influence personality, these were only asked of respondents in 2004. Rather than offering a dichotomous genes or environment answer like the item discussed in the previous post did, each of these questions allows respondents to answer on a sliding scale from 1 to 21, with 1 representing 100% genetic, 0% environmental, 2 representing 95% genetic, 5% environmental, etc.

Following are the percentages of each racial group for which a sufficient sample size existed that thought genetic influences were more important (1-10), environmental influences were more important (12-21), or the two were equally important (11), prefaced by a description of the scenario being inquired about (with respondents being called upon to give the reason for the situation). The sample size is 1,850 for whites, 272 for blacks, and 76 for Hispanics*:

An overweight white woman has lost weight before, but she always gains it back.

A black man is an all-around athlete who was on the varsity swim (!) team and continues to work out five times a week.

A Hispanic woman is always helpful and never has a negative word to say about anybody.

An Asian man regularly becomes too drunk to remember anything that happens during these drinking episodes.



The bar graph aggregates the responses for all four questions by race (click for better resolution). Blacks and Hispanics are consistently more likely to attribute behavior and attributes to genetic influences than whites are.

The black athlete scenario elicits the greatest attribution to genetic influences of the four questions for all three groups. Appealing to a person's knowledge of sports is one of the best avenues to take in getting him to think about human biodiversity. In addition to the evidence marshalled in books like Jon Entine's Taboo, he has his own lying eyes to contend with.


* As defined by those who choose "Hispanic" as their race of first mention when prompted to select from a list including 16 categories. The US Census, for which no "Hispanic" option is given for racial self-description, shows that 48% of Hispanics consider themselves white, 42% choose "other", 2% self-describe as black, and the remainder choose two or more races.

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