1 point) A recent study in the Journal of the American MedicalAssociation reported the results of an experiment where 40overweight individuals followed the Weight Watchers diet for oneyear. Their weight changes at the end of the year had a mean of?¯=3.1x¯=3.1 kg with a standard deviation of ?=4.7s=4.7 kg. We wantto use this data to test the claim that the diet has an effect,that is, that the weight change is higher than 0.

1. Which set of hypotheses should be used fortesting this claim?
A. ?0:?=3.1H0:μ=3.1 vs.??:?>3.1Ha:μ>3.1
B. ?0:?=0H0:μ=0 vs. ??:?>0Ha:μ>0
C. ?0:?=0H0:μ=0 vs. ??:?≠0Ha:μ≠0
D. ?0:?=0H0:μ=0 vs. ??:?<0Ha:μ<0

2. Which of the following conditions must bemet for the hypothesis test to be valid? Check all thatapply.

A. The amount each person's weight changed must beindependent of the amount other participant's weightschanged.
B. There must be at least 10 people who'succeeded' on the diet and 10 who 'failed'.
C. There must be at least 5 people who followedthe diet for a full year.
D. The weight loss measurements for people in thesample must be normally distributed.
E. The sample size must be at least 30 or thepopulation data for weight loss must be normally distributed.

3. Calculate the test statistic:

4. Calculate the p-value:

5. Calculate the effect size, Cohen's ?d, forthis test: ?Ì‚=d^=

6. The results of this test indicate we havea...
A. small
B. small to moderate
C. large
D. moderate to large
effect size, and...
A. very strong evidence
B. extremely strong evidence
C. little evidence
D. some evidence
E. strong evidence
that the observed result is not due to chance, assuming the nullmodel is true.

6. A 95% confidence interval for the meanweight change (in kg) for people on this diet is (1.6, 4.6). Whichof the statements below is correct?
A. There is a 95% chance that 95% of theindividuals in the study who followed the diet for one year lost atleast 1.6 kg.
B. We can be 95% confident that the mean weightloss for the population of people for whom the sample participantsare a representative sample is between 1.6 kg and 4.6 kg.
C. We can be confident that 95% of the individualswho follow this diet for one year will lose between 1.6 kg and 4.6kg.