A researcher believes she has developed a new medicine that has
a positive effect on cognitive functioning in the population. To
test her hypothesis, the researcher takes a random sample of 61
participants and conducts a repeated measures experiment. She first
measures the cognitive functioning levels of the 61 participants
before they are given the medicine. She then measures the cognitive
functioning of the same 61 participants after they are given the
medicine. Descriptive statistics for the sample are given below.
Sample mean cognitive functioning before taking the medicine: 100
Sample mean cognitive functioning after taking the medicine: 102
Sample mean difference, (μd): 2 Sample variance of the differences,
(s 2 ): 150
(1A) The researcher plans to do a one-tailed hypothesis with
alpha = 0.05. What are the correct null and alternative hypotheses?
(10 pts)
(1B) What is the t-statistic? (10 pts)
(1C) Do you reject or fail to reject the null hypothesis? Write
your conclusion in your own words. (10 pts) (2) What assumptions do
we make for this related samples t-test? (10 pts)