Question 7
A pharmaceutical company is testing a new drug to increase
memorization ability. It takes a sample of individuals and splits
them randomly into two groups. One group is administered the drug,
and the other is given a placebo. After the drug regimen is
completed, all members of the study are given a test for
memorization ability with higher scores representing a better
ability to memorize. You are presented a 90% confidence interval
for the difference in population mean scores (with drug - without
drug) of (-4.63, 5.43). What can you conclude from this
interval?
1)
We are 90% confident that the average memorization ability of
those on the drug is higher than those who are not on the
drug.
2)
There is no significant difference between the average
memorization abilities for those on the drug compared to those not
on the drug.
3)
We do not have enough information to make a conclusion.
4)
We are 90% confident that the average memorization ability of
those not on the drug is higher than those who are on the
drug.
5)
We are 90% confident that the difference between the two sample
means falls within the interval.
Question 8
The owner of a golf course wants to determine if his golf course
is more difficult than the one his friend owns. He has 28 golfers
play a round of 18 holes on his golf course and records their
scores. Later that week, he has the same 28 golfers play a round of
golf on his friend's course and records their scores again. The
average difference in the scores (treated as the scores on his
course - the scores on his friend's course) is 4.29 strokes and the
standard deviation of the differences is 9.244 strokes. The owner
uses this information to calculate the 99% confidence paired
t-interval of (-0.55, 9.13). Which statement is the correct
interpretation of this interval?
1)
We are 99% confident that the average difference in scores
between the two courses for all golfers is between -0.55 and
9.13.
2)
We are 99% confident that the difference between the average
score on the owner's golf course and the average score on the
friend's golf course is between -0.55 and 9.13.
3)
We are 99% confident that the average difference in the scores
of the golfers sampled is between -0.55 and 9.13.
4)
We are certain the average difference in scores between the two
courses for all golfers is between -0.55 and 9.13.
5)
The proportion of all golfers that had a difference in scores
between the two courses is 99%.
Question 9
You hear on the local news that for the city of Kalamazoo, the
proportion of people who support President Trump is 0.54. However,
you think it is greater than 0.54. The hypotheses for this test are
Null Hypothesis: p ≤ 0.54, Alternative Hypothesis: p > 0.54. If
you randomly sample 20 people and 7 of them support President
Trump, what is your test statistic and p-value?
1)
Test Statistic: 1.705, P-Value: 0.956
2)
Test Statistic: -1.705, P-Value: 0.044
3)
Test Statistic: -1.705, P-Value: 1.912
4)
Test Statistic: -1.705, P-Value: 0.956
5)
Test Statistic: 1.705, P-Value: 0.044