The data set lowbwt contains information recorded for a sample of 100 low birth weight infants – those weighing less than 1500 grams – born in two teaching hospitals in Boston, Massachusetts (Appendix B, Table B.7). Measurements of infant systolic blood pressure are saved under the variable name sbp while indicators of gender – where 1 represents a male and 0 a female – are saved under the same sex.
a. compute a 95% confidence interval for the true mean systolic blood pressure of male low birth weight infants.
b. calculate a 95% confidence interval for the true mean systolic blood pressure of female low birth weight infants.
c. Do you think it is possible that males and females have the same mean systolic blood pressure? Explain briefly.