The United States Public Health Service and Tuskegee Institute in Alabama studied the effects of the disease syphilis on a group of poor African-American men.

VOA: special.2010.07.21

I think the answer is that both play a role but some of the effects are due to stereotypes above and beyond in-group favoritism.

我想两者都有,但刻板印象的影响,要高于组内偏爱。

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