Refer to the previous exercise. For these data, MINITAB reports
Point estimate for ETA1-ETA2 is -2.000.
95.9 Percent CI for ETA1-ETA2 is (-3.300, -0.700).
W = 31.0.
Explain how to interpret the reported
(a) Point estimate and
(b) Confidence interval.
Previous exercise
Smoking during pregnancy is a known cause of reduced infant birth weight and other issues that can affect the delivery and mortality. Despite this strong evidence, women who smoke find it difficult to quit even when they are pregnant. Suppose a study is done measuring the birth weight of babies of mothers who smoked during pregnancy and those who did not smoke. The birth weight data in pounds are:
Smokers: 3.1, 4.2, 4.5, 5.0, 6.4, 4.7, 6.0
Nonsmokers: 5.5, 6.5, 7.1, 8.0, 6.8, 7.5, 6.2