According to the U.S. Department of Health and Human Services, African American women have the highest rates of being overweight compared to other groups in the United States. Individuals are considered overweight if their body mass index (BMI) is 25 or greater. Data are collected from 120 individuals. The following table shows a portion of data on each individualâs BMI, a Female dummy variable that equals 1 if the individual is female, 0 otherwise, and a Black dummy variable that equals 1 if the individual is African American, 0 otherwise.
a. Estimate the model, BMI = β0 + β1Female + β2Black + β3(Female à Black) + ε, to predict the BMI for white males, white females, black males, and black females.
b. Is the difference between white females and white males statistically significant at the 5% level?
c. Is the difference between white males and black males statistically significant at the 5% level?
BMI Female Black 28.70 1 28.31 24.90 1
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