In order to test the effectiveness of a new drug in reducing
cholesterol level, a random sample of 45 patients who have a higher
than normal cholesterol level was chosen. The cholesterol level of
each of the patients was measured and recorded before and then
after taking the new drug for a period of 6 weeks, and the
differences (before - after) were calculated. The appropriate set
of hypotheses, in this case, is:
(Ho: μd = 0) and (Ha: μd < 0)
(Ho: μd = 0) and (Ha: μd > 0)
(Ho: μd = 0) and (Ha: μd ≠ 0)
None of the above. This is not a matched pairs situation.