Is the Diet Practical? When 40 people used the Weight Watcher diet for one year, their mean weight loss was 3.0lb and the standard deviation was 4.9 lb (based on data from "Comparison of the Atkins, Ornish, Weight Watcher, and Zone Diets for Weight Loss and Heart Disease Reduction, "by Dansinger, et. al, Journal of the American Medical Association, Vol. 293, No. 1). Use a 0.01 significance level to test the claim that the mean weight loss is greater than 0 lb.
- What are your null and alternative hypotheses?
- What is your test statistic?
- Which method did you use to test your hypothesis?
- Based on these results, does the diet appear to be effective?
- Does the diet appear to have practical significance?