A researcher is interested to see if walking for 30 minutes a day helps women lose weight. A random sample of 40 women participated in the study. Their weight before the experiment was recorded. The women were asked to walk 30 min every day for 30 days. When the experiment
was over, they were weighed again. The difference between the "before" weight and the "after weight was found. In other words, D = Before After. Their mean difference of weights was xD = 2:2 and the standard deviation of the difference was sD = 5. Test the research hypothesis.
(a) What is the parameter of interest?
(b) Calculate the test statistic.
(c) What is the p-value?
(d) State your conclusion.
(a) What is the parameter of interest?
(b) Find a 95% CI for the di erence in proportion for males and females would have driven greater than 100 mph.
(c) Does the interval calculated in part (b) contain 0? What does this tell us about whether there is a di erence in the proportion?