J. Greene and J. Touchstone conducted a study on the relationship between the estriol levels of pregnant women and the birth weights of their children. Their findings, “Urinary Tract Estriol: An Index of Placental Function,” were published in the American Journal of Obstetrics and Gynecology (Vol. 85(1), pp. 1–9). The data points are provided on the WeissStats CD, where estriol levels are in mg/24 hr and birth weights are in hectograms (hg).
a. Obtain and interpret the standard error of the estimate.
b. Obtain a residual plot and a normal probability plot of the residuals.
c. Decide whether you can reasonably consider Assumptions 1–3 for regression inferences met by the two variables under consideration.