Question 1 For which of the following situations would a repeated-measures study be appropriate?

studies.

degrees of freedom
MD
individual differences
the effect of the treatment

Question 3

A manager would like to know if the performance of sales representatives significantly (α = .05) improves over the first 6 months of employment. For 5 new sales representatives, the number of sales in the first month is recorded and the number of sales in the sixth month is recorded. What is the null hypothesis for this repeated measures t-test?

µD = 0
µD > 0
µ1 = µ2
µD ≤ 0
µ ≤ 5
µ1 > µ2

Question 4

t crit = 2.132
t crit = ± 2.776
t crit = 2.015
t crit = ± 2.571
t crit = 0.471
t crit = 0.727

Question 5

A manager would like to know if the performance of sales representatives significantly (α = .05) improves over the first 6 months of employment. For 5 new sales representatives, the number of sales in the first month is recorded and the number of sales in the sixth month is recorded. The sales numbers at the 1st and 6th month are given below. What is the test statistic, decision, and appropriate conclusion for this repeated measures t-test?

1st6th1501451202201001401551558090

t = 1.533 Reject the null hypothesis; results suggest the performance of sales representatives significantly improves over the first 6 months of employment
t = 1.533 Fail to reject the null hypothesis; results suggest the performance of sales representatives does not significantly improve over the first 6 months of employment
t = 1.533 Fail to reject the null hypothesis; results suggest the performance of sales representatives significantly improves over the first 6 months of employment
t = .669 Fail to reject the null hypothesis; results suggest the performance of sales representatives does not significantly improve over the first 6 months of employment
t = .669 Fail to reject the null hypothesis; results suggest the performance of sales representatives significantly improves over the first 6 months of employment
t = .669 Reject the null hypothesis; results suggest the performance of sales representatives significantly improves over the first 6 months of employment
t = 1.496 Fail to reject the null hypothesis; results suggest the performance of sales representatives does not significantly improve over the first 6 months of employment
t = 1.496 Fail to reject the null hypothesis; results suggest the performance of sales representatives significantly improves over the first 6 months of employment
t = 1.496 Reject the null hypothesis; results suggest the performance of sales representatives significantly improves over the first 6 months of employment

Question 6

A researcher obtains t = 2.80 for a repeated-measures study examining the difference in reading ability before and after completing a reading comprehension course among a sample of n = 16 participants. Based on this t value, what is the correct decision for a two-tailed test?

Reject the null hypothesis with α = .05 but not with α = .01.
Fail to reject the null hypothesis with either α = .05 or α = .01.
Reject the null hypothesis with either α = .05 or α = .01.
cannot make a decision without additional information

Question 7

r2 = .149
r2 = .329
r2 = .343
cannot be determined with the information given.

Question 8

For the repeated measures t-test, the value of r2 tells you ___.

the proportion of differences in the dependent variable which can most likely be attributed to the independent variable
the proportion of differences in the independent variable which can most likely be attributed to the dependent variable
the proportion of differences between two measures of the dependent variable which can be accounted for by individual differences
the proportion of differences between two measures of the independent variable which can be accounted for by individual differences