As the United States has struggled with the growing obesity of its citizens diets have become big business. Among the many competing regimens for those seeking weight reduction are the Atkins and Zone diets. In a comparison of these two diets for one-year weight loss, a study found that 77 subjects on the Atkins diet had an average weight loss of x? = ?4.7 kg and a sample standard deviation of sX = 7.05 kg. Similar figures for the 79 people on the Zone diet, where y? = ?1.6 kg and sY = 5.36 kg. Is the greater reduction with the Atkins diet statistically significant? Test for ? = 0.05.
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In this study, the average weight loss for the Atkins group was x -4.7 kg and the average weight loss for the Zone group was y -1.6 kg. The standard error of the difference is Sx 7.05 kg. Show more…
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