Question:
The “Freshman 15” refers to the urban legend that is the common belief that students gain an average of 15 lb (or 6.8 kg) during their freshman year. Refer to Data Set 4 in Appendix B and consider the sample values in this format: (April weight) — (September weight). In this format, positive differences represent gains in weight, and negative differences represent losses of weight. If we use µd to denote the mean of the “April — September” differences in weights of college students during their freshman year, the “Freshman 15” is the claim that µd = 15 lb or µd = 6.8 kg. Test the claim that µd = 6.8 kg using a 0.05 significance level with the 67 subjects from Data Set 4 in Appendix B. What do these results suggest about the “Freshman 15”?