# The power of the t test increases with | Complete Solution

1. The power of the t test increases with ____.
increases in N
increases in the effect of the independent variable
decreases in the sample variance(s)
all of the other three options

2. Having just made what you feel is to be a Type II error, using an independent groups design and a t test analysis, which of the following might you do in the next experiment to reduce the probability of a Type II error?
increase N
change to a correlated groups design
try to reduce the variance by better experimental control
all of the other three options

3. The t test for correlated groups requires that ____.
the sampling distribution of is normally distributed
N ³ 30
the population raw scores are normally distributed
the sampling distribution of is normally is normally distributed

4. In the t test for independent groups, ____.
we estimate µ1- µ2
we estimate s2
we estimate
df = N - 1

5. Exhibit 14-1
A professor of women's studies is interested in determining if stress affects the menstrual cycle. Ten women are randomly sampled for an experiment and randomly divided into two groups. One of the groups is subjected to high stress for two months while the other lives in a relatively stress-free environment. The professor measures the menstrual cycle (in days) of each woman during the second month. The following data are obtained.
High stress 20 23 18 19 22
Relatively stress free 26 31 25 26 30
Refer to Exhibit 14-1. The obtained value of the appropriate statistic is ____.
tobt = -4.73
tobt = -4.71
tobt = -3.05
tobt = -0.47

6. Exhibit 14-1
A professor of women's studies is interested in determining if stress affects the menstrual cycle. Ten women are randomly sampled for an experiment and randomly divided into two groups. One of the groups is subjected to high stress for two months while the other lives in a relatively stress-free environment. The professor measures the menstrual cycle (in days) of each woman during the second month. The following data are obtained.
High stress 20 23 18 19 22
Relatively stress free 26 31 25 26 30
Refer to Exhibit 14-1. The df for determining tcrit are ____.
4
9
8
3

6. Exhibit 14-1
A professor of women's studies is interested in determining if stress affects the menstrual cycle. Ten women are randomly sampled for an experiment and randomly divided into two groups. One of the groups is subjected to high stress for two months while the other lives in a relatively stress-free environment. The professor measures the menstrual cycle (in days) of each woman during the second month. The following data are obtained.
High stress 20 23 18 19 22
Relatively stress free 26 31 25 26 30
Refer to Exhibit 14-1. Using a= .052 tail, tcrit= ____.
+2.162
+2.506
±2.462
±2.306

7. Exhibit 14-1
A professor of women's studies is interested in determining if stress affects the menstrual cycle. Ten women are randomly sampled for an experiment and randomly divided into two groups. One of the groups is subjected to high stress for two months while the other lives in a relatively stress-free environment. The professor measures the menstrual cycle (in days) of each woman during the second month. The following data are obtained.
High stress 20 23 18 19 22
Relatively stress free 26 31 25 26 30
Refer to Exhibit 14-1. Using a= .052 tail, your conclusion is ____.
accept H0; stress does not affect the menstrual cycle
retain H0; we cannot conclude that stress affects the menstrual cycle
retain H0; stress affects the menstrual cycle
reject H0; stress affects the menstrual cycle

8. Exhibit 14-1
A professor of women's studies is interested in determining if stress affects the menstrual cycle. Ten women are randomly sampled for an experiment and randomly divided into two groups. One of the groups is subjected to high stress for two months while the other lives in a relatively stress-free environment. The professor measures the menstrual cycle (in days) of each woman during the second month. The following data are obtained.
High stress 20 23 18 19 22
Relatively stress free 26 31 25 26 30
Refer to Exhibit 14-1. Estimate the size of the effect.= ____
0.8102
0.6810
0.4322
0.5776

9. Which of the following tests analyzes the difference between the means of two independent samples?
correlated t test
t test for independent groups
sign test
test of variance

10. Which of the following is (are) assumption(s) underlying the use of the F test?
the raw score populations are normally distributed
the variances of the raw score populations are the same
the mean of the populations differ
the raw score populations are normally distributed and the variances of the raw score populations are the same

11. If its assumptions are met, the analysis of variance technique is appropriate when ____.
two or more factors are varied
several levels of a single independent variable are compared
three or more groups are involved
all of the other three options

12. sB2is a measure of ____.
s 2 alone
s 2 + the effects of the independent variable
the variability between the means
s 2 + the effects of the independent variable and the variability between the means

13. The total degrees of freedom for an experiment with n1= 10,n2= 12, and n3= 10 is ____.
2
32
31
29

14. Exhibit 15-3
Pertain to the following data.
Group 1- 4, 9, 10
Group 2- 11, 11, 10
Group 3- 1, 6, 4
Refer to Exhibit 15-3. What is the value of Fobt?
5.67
6.53
1.95
3.26
15. Exhibit 15-3
Pertain to the following data.
Group 1- 4, 9, 10
Group 2- 11, 11, 10
Group 3- 1, 6, 4
Refer to Exhibit 15-3. What is the value of Fcrit? Use a= 0.05.
5.14
4.76
4.46
4.07
16. Exhibit 15-3
Pertain to the following data.
Group 1- 4, 9, 10
Group 2- 11, 11, 10
Group 3- 1, 6, 4
Refer to Exhibit 15-3. What is your conclusion? Again use a = 0.05
retain H0
reject H1
reject H0
accept H0

17. Exhibit 15-3
Pertain to the following data.
Group 1- 4, 9, 10
Group 2- 11, 11, 10
Group 3- 1, 6, 4
Refer to Exhibit 15-3. Using, the estimated size of effect is ____.
22.6% of the variability
52.8% of the variability
43.6% of the variability
55.1% of the variability
18.
Exhibit 15-3
Pertain to the following data.
Group 1- 4, 9, 10
Group 2- 11, 11, 10
Group 3- 1, 6, 4
Refer to Exhibit 15-3. Using 2, what is the estimated size of effect?
0.7232
0.6852
0.6582
0.6312
19. What is the value of SST if SSB = 236 and SSW = 54?
290
182
4.37
100

20. By doing multiple t tests when there are more than 2 experimental groups we increase the risk of making what kind of mistake?
accepting H0
Type I error
Type II error
all of the other three options

21. If X1=46, X2= 50, X3= 92 and n1=n2=n3, what is the value of Xg?
cannot be determined from information given
50.0
188.0
62.67

22. If SSW= 126,N= 28,k= 4, then what is the value of sW2
cannot be determined from information given
5.25
42.0
4.667

23. If dfB= 3 and dfT= 29 and Fobt= 3.15, what would you conclude using a= 0.05?
reject H0
reject H1
retain H0
retain H1

24. IfsB2= 27.9 andsW2= 54.2, what is the value ofFobt?
impossible result, there must be an error
1.94
0.51
2.76

25. A priori comparisons ____.
are planned in advance of the experiment
often arise out of theory and prior research
may be done without obtaining a significant Fobt in the one-way ANOVA
all of the other three options

26. The sampling distribution of chi-square is ____.
skewed
varies with df
is a theoretical distribution
all of the other three options

27. The computation of fe____.
is based on population proportion estimates
is based on known population proportions
is based on population means
none of the other three options

28. If N= 18 and a= 0.052 tailed, the value of Tcrit is ____.
40
±39
-41
47

29. If a= 0.05, and df = 4, the value of c 2crit= ____.
9.488
0.711
7.815
11.070

30. Exhibit 17-1
Prior to a recent gubernatorial election, a survey was conducted to determine whether there was a relationship between sexual gender and preference for the Democratic or Republican candidate. The following data were recorded.

Republican Female: 82 Democrat Female: 118 -- 200
Republican Male: 68 Democrat Male: 132 -- 200
--150 --250 --400

Refer to Exhibit 17-1. The value of c 2obt= ____.
2.06
2.09
1.80
1.75

31. Exhibit 17-1
Prior to a recent gubernatorial election, a survey was conducted to determine whether there was a relationship between sexual gender and preference for the Democratic or Republican candidate. The following data were recorded.

Republican Female: 82 Democrat Female: 118 -- 200
Republican Male: 68 Democrat Male: 132 -- 200
--150 --250 --400
Refer to Exhibit 17-1. The value of df = ____.
2
1
3

32. Exhibit 17-1
Prior to a recent gubernatorial election, a survey was conducted to determine whether there was a relationship between sexual gender and preference for the Democratic or Republican candidate. The following data were recorded.

Republican Female: 82 Democrat Female: 118 -- 200
Republican Male: 68 Democrat Male: 132 -- 200
--150 --250 --400
Refer to Exhibit 17-1. Using a= 0.05,c 2crit= ____.
3.841
5.412
2.706
-3.841

33. Exhibit 17-1
Prior to a recent gubernatorial election, a survey was conducted to determine whether there was a relationship between sexual gender and preference for the Democratic or Republican candidate. The following data were recorded.

Republican Female: 82 Democrat Female: 118 -- 200
Republican Male: 68 Democrat Male: 132 -- 200
--150 --250 --400
Refer to Exhibit 17-1. Using a= 0.05, what is your conclusion?
accept H0; there is no relationship between sex and candidate preference
reject H0; there is a significant relationship between sex and candidate preference
retain H0; the study does not show a significant relationship between sex and candidate preference
retain H0; this study shows a significant relationship between sex and candidate preference

34. As the separation between the two groups of scores increases, Uobt ____.
increases
decreases
stays the same
approaches U¢obt
35. The statistics (U or U') used in the Mann-Whitney U test, measure ____.
the differences between the means of the two groups
the direction of the differences between pairs of scores
the power of the experiment
the separation between the two groups
36. Using SPSS, the appropriate steps to analyze data for student’s t test for correlated groups are _________
Compare Means Paired Sample t test Before_C After_C
Analyze Compare Means Paired Sample t test After_C Before_C
Analyze Compare Means Paired Sample t test Before_C After_C
Analyze Compare Means Before_C After_C
37. In SPSS, the results of analysing data for student’s t test are displayed ____.
in a graph
in a number of tables
as a stem and leaf
in a histogram
38. In SPSS, the appropriate steps to analyze data for a one-way ANOVA are ____.
you cannot perform ANOVA in SPSS
One-Way ANOVA Analyze Compare Means
Compare Means One-Way ANOVA
Analyze Compare Means One-Way ANOVA
39. In SPSS, when you follow the steps to perform one-way ANOVA, ____.
you will not be given the option to compute “descriptive statistics”
you will be given the option to compute “descriptive statistics”
you will be given the option to compute “descriptive statistics”, but you have to open a new file
you will be given the option to compute “descriptive statistics”, but you have to restart SPSS