In: Statistics and Probability
Research Question: Do soccer players who lift weights during the season significantly differ in the number of practices they miss (due to injury) during the three month-season from players who do not regularly lift weights? The data set is below:
Players who lift weights
Number of practices missed
Players who do NOT lift weights
Number of practices missed
Player 1: 4
Player 2: 6
Player3: 4
Player 4: 10
Player 5: 1
Player 6: 7
Player 7: 3
Player 8: 1
Player 9: 4
Player 10: 2
Player 11: 13
Player 12: 2
Player 13:9
Player 14: 4
Player 15: 9
Player 16: 12
Player 17: 15
Player 18: 13
Player 19: 6
a. Identify the 2 populations.
b. Identify the comparison distribution.
c. Which inferential statistical test will you use and why?
d. What are the assumptions of this test and are any violated?
e. Is this a one-tailed or two-tailed test? What are the null and research hypotheses?
f. What are mean and standard error of the comparison distribution? You must show your work to earn points for standard error. Just type in what the mean is. It is always the same for this comparison distribution.
g. What are the critical cut-offs for this test assuming p = .05?
h. What is the test statistic? Show your work.
i. What is your decision: Reject or fail to reject the null hypothesis?
j. Please calculate a 95% CI for this problem and interpret it. Show your work.
k. Please calculate Cohen’s d for this problem and interpret it. Show your work.