The power of the t test increases with complete answers

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

need more information


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