The time (in minutes) that a subject spent on a psychological test was used as a measure of cognitive function. 41 schizophrenics (2) and 49 non-schizophrenics (1) were given the test, and their time was recorded. Psychologists theorize that the mean time on the test for non-schizophrenics will be less than the mean for schizophrenics.

1) Which test should be used to test the theory that the mean time on the test for non-schizophrenics will be less than the mean for schizophrenics?

a) t test for means

b) z test for proportions

c) z test for means

d) paired t test for means

e) paired z test for means

2) Which alternative hypothesis should be used to test the theory that the mean time on thetest for non-schizophrenics will be less than the mean for schizophrenics?

a) HA:12>0

b) HA:p1p2>0

c) HA:p1p20

d) HA:p1p2<0

e) HA:12<0

f) HA: u1-u10

3) The p-value of the test is .0202. What is the conclusion of the test at=.05?

a) RejectH0. There is insufficient evidence at =.05 to conclude that the mean time on thetest for non-schizophrenics is less than the mean for schizophrenics.

b) Fail to reject H0. There is insufficient evidence at =.05 to conclude that the mean time on thetest for non-schizophrenics is less than the mean for schizophrenics.

c) Fail to reject H0. There is sufficient evidence at=.05 to conclude that the mean time on thetest for non-schizophrenics is less than the mean for schizophrenics.

d) RejectH0. There is sufficient evidence at=.05 to conclude that the mean time on thetest for non-schizophrenics is less than the mean for schizophrenics.

4) A 90% confidence interval for12 is (-4.3, -1.9). Interpret the interval.

a) With 90 % confidence, the mean time on the test for non-schizophrenics is between 1.9 and 4.3 minutes less than the mean time for schizophrenics.

b) With 90 % confidence, the mean time on the test for non-schizophrenics is between 1.9 and 4.3 minutes more than the mean time for schizophrenics.

c) At the 90% level of confidence, there is not sufficient evidence to conclude that the mean time on the test for non-schizophrenics differs from the mean time for schizophrenics.

400 UCF students were randomly selected and asked if they preferred washing their hands with soap and water or using hand sanitizer. 102 said they prefer to use hand sanitizer. 400 USF students were randomly selected and asked the same question. 112 said they prefer to use hand sanitizer. You want to examine the difference in the proportion of all UCF (1) and USF (2) students who prefer to use hand sanitizer.

1) Which test should be used to determine if a difference exists between the proportion of all UCF and USF students who prefer to use hand sanitizer?

a) paired t test for means

b) t test for means

c) paired z test for means

d) z test for means

e) z test for proportions

2) Which alternative hypothesis should be used to determine if a difference exists betweenthe proportion of all UCF and USF students who prefer to use hand sanitizer?

a) HA:12<0

b) HA:p1p2<0

c) HA:12>0

d) HA:p1p2>0

e) HA:p1p20

f) HA:120

3) The p-value of the test is .4245. What is the conclusion of the test at=.10 ?

a) Reject H0. There is insufficient evidence at=.10 to conclude that a difference exists between the proportion of all UCF and USF students who prefer to use hand sanitizer.

b) Fail to rejectH0. There is insufficient evidence at=.10 to conclude that a difference exists between the proportion of all UCF and USF students who prefer to use hand sanitizer.

c) Reject H0. There is sufficient evidence at =.10 to conclude that a difference exists between the proportion of all UCF and USF students who prefer to use hand sanitizer.

d) Fail to rejectH0. There is sufficient evidence at =.10 to conclude that a difference exists between the proportion of all UCF and USF students who prefer to use hand sanitizer.

4) A 90% confidence interval forp1p2is ( - 0.0765, 0.02646). Interpret the interval.

a) With 90% confidence, the proportion of all UCF students who prefer hand sanitizer is between 2.646% and 7.65% more than the proportion of all USF students who prefer to use hand sanitizer.

b) At the 90% level of confidence, there is insufficient evidence to conclude that there exists a difference between the proportion of all UCF and USF students who prefer to use hand sanitizer.

c) With 90% confidence, the proportion of all UCF students who prefer hand sanitizer is between 2.646% and 7.65% less than the proportion of all USF students who prefer to use hand sanitizer.