Question

A researcher is interested in how diet affects athletic performance. She instructs one group of participants to consume a high protein diet, a second group to consume a low sugar diet, and a third group to not change their diet at all (to eat as they normally would) for 3 weeks. She compares the amount of time it takes participants in each group to run one mile.

1. What is the null hypothesis?

A. H0: µ1 = µ2 =µ3

B. H0: r = 0

C. H0: X = µ

D. H0: µposttest = µpretest

2. What is the alternative hypothesis?

A. H₁: R_xy > 0

B. H₁: X ≠ µ

C. H₁: µ1 ≠ µ2 ≠µ3

D. H₁: µposttest ≠µpretest

3. What is the appropriate test statistic to use?

A. z-score

B. independent samples t-test

C. z-test

D. correlation coefficient

E. regression

F. one-way ANOVA

G. dependent samples t-test

4. What is the independent variable?

A. The amount of exercise each participant does each week

B. The participant’s diet

C. The participants

D. The amount of time it takes them to run one mile

E. The protein in their diet

5. What is the dependent variable?

A. The amount of exercise each participant does each week

B. The protein in their diet

C. The participant’s diet

D. The amount of time it takes them to run one mile

E. The participants

Answer 1

question 1 : A ( There will be no difference in the mean score of three groups with respect to the amount of time they take to run a mile after three weeks of diet change)

question 2 : C (there will a difference in the mean score of the three groups with respect to the amount of time they take to run a mile after three weeks of diet change)

question 3: F (One - way ANOVA will be the best measure to understand the statistical difference between the three groups as more than two independent groups are present)

question 4: B (since the manipulation of the participant's diet is expected to change the time taken to run a mile at the 3 weeks therefore participant's diet is the independent variable)

question 5 : D ( the effect of diet's change is expected to have an effect on the amount of time taken for running a mile , therefore the amount of time taken to run a mile is the dependent variable)