Homework MCQs

1.

1 point

Which of the following is the most appropriate description of a Type II error?

Reject the null hypothesis when it is false

Fail to reject the null hypothesis when it is false

Fail to reject the null hypothesis when it is true

Reject the null hypothesis when it is true

2.

1 point

When the null hypothesis is true for an ANOVA, what is the expected value for the F-ratio?

k-1

0

1.00

n-k

3.

1 point

An independent-measures t hypothesis test is appropriate when ____.

the mean for a treated group of subjects is compared to a known population mean

one sample is used to test a hypothesis about one population

there are two separate samples containing different subjects

the value for s is known

4.

1 point

What is the value of SS for the following sample?

SS= 8/2

SS= 8

SS= 8*8

SS= 8/3

5.

1 point

Which of the following is a two-tailed hypothesis?

We predict that the scores of Group B should be significantly higher than the scores of Group A

We predict a positive relationship between the scores of Group A and Group B

We predict that the scores of Group A should be significantly higher than the scores of Group B

We predict a significant difference between the scores of Group A and Group B

6.

1 point

Run an independent samples t-test on the data file (Week8_Homework_Data.sav).

What are the mean and SD for females?

6.30; 1.50

6.28; 1.47

6.27; 1.63

6.26; 1.79

7.

1 point

Run an independent samples t-test on the data file (Week8_Homework_Data.sav).

What are the degrees of freedom for the t-test?

96

100

98

99

8.

1 point

When we convert a score into a score from a probability distribution, it becomes a _______

Test statistic

Significance value

Test score

Probability

9.

1 point

The first step in hypothesis testing is to:

Decide whether to reject or fail to reject the null hypothesis

Calculate the p value

Measure the relationship between variables

Generate a hypothesis

10.

1 point

The results of an independent-measures research study are reported as "t(5) = -2.12, p = .67, two tails." What statistical decision was made?

The researcher failed to reject H0.

The null hypothesis was rejected

The was a marginally significant effect

Cannot be determined from the researcher's statement

11.

1 point

Which of the following is an example of a null hypothesis?

The scores of Group A and Group B will not differ significantly

The scores of Group A will be greater than the scores of Group B

The scores of Group A and Group B will differ significantly

The scores of Group A will correlate with the scores of Group B

12.

1 point

For the repeated-measures t statistic, df = ____.

n1 + n2 - 1

n1 + n2 - 2

n-1

(n1 - 1) + (n2 - 1)

13.

1 point

Which of the following sets of correlations correctly shows the highest to lowest degree of relationship?

-0.91, +0.83, -0.03, -0.10

+0.83, +0.10, -0.91, -0.03

-0.91, +0.83, +0.10, -0.03

+0.83, +0.10, -0.03, -0.91

14.

1 point

Which of the following sets of data is most likely to produce a significant t statistic? NB: MD = Mean Difference, SS = Sum of Squared Deviations

MD = 2 and SS = 100

MD = 2 and SS = 10

MD = 10 and SS = 10

MD = 10 and SS = 100

15.

1 point

For a population with μ = 100 and σ = 20, the X value corresponding to z = 1.50 is

x = 101.5

x = 121.5

x = 115

x = 130

16.

1 point

A researcher conducts an experiment and discovers a significant (p < .05) difference between her two experimental groups. What is the next step she should take?

Reject the null hypothesis

Accept the alternate hypothesis

Fail to reject the null hypothesis

Fail to accept the alternate hypothesis

17.

1 point

t(98)= -0.061, p= .952, d= 0.012

Based on the t statement, what decision should the experimenter make?

There is not enough information to make a decision

Accept the null hypothesis

Fail to reject the null hypothesis

Reject the null hypothesis

18.

1 point

In N = 25 games last season, the college basketball team averaged μ = 74 points with a standarddeviation of σ = 6. In their final game of the season, the team scored 90 points. Based on thisinformation, the number of points scored in the final game was ____.

above average, but impossible to describe how much above average

far above average

There is not enough information to compare last year with the average

a little above average

19.

1 point

For an experiment comparing two treatment conditions, an independent-measures design would obtain ____ score(s) for each subject and a repeated-measures design would obtain ____ score(s) for each subject.

2, 1

1, 2

2, 2

1, 1

20.

1 point

An independent-measures experiment uses one sample with n = 10 and a second sample with n = 15 to compare two experimental treatments. The t statistic from this experiment will have degrees of freedom equal to ____.

25

24

23

cannot be determined with unequal sample sizes

21.

1 point

A researcher decides to run a correlation to discover whether a positive relationship exists between variable X and variable Y. He should conduct a _____.

1 tailed test

Type 1 test

2 tailed test

Type 2 test

22.

1 point

A repeated-measures study finds a mean difference of MD = 5 points between two treatment conditions. Which of the following sample characteristics is most likely to produce a significant t statistic for the hypothesis test?

a small sample size (n) and a small variance

a large sample size (n) and a small variance

a small sample size (n) and a large variance

a large sample size (n) and a large variance

23.

1 point

In a repeated-measures experiment, each individual participates in one treatment condition and then moves on to a second treatment condition. One of the major concerns in this type of study is that participation in the first treatment may influence the participant's score in the second treatment. This problem is called ____.

individual differences

homogeneity of variance

bi-treatment effect

order effects

24.

1 point

A repeated-measures experiment and a matched-subjects experiment both produce t statistics with df = 20. Which experiment used more subjects

They both used n = 22 subjects.

They both used n = 21 subjects.

matched subjects

repeated measures

25.

1 point

For a population with μ = 60 and σ = 8, what is the X value corresponding to z = -0.50?

56

64

-4

59.5

26.

1 point

A population of N = 5 scores has SS = 40. What is the variance for this population?

40/5 = 8

5(40) = 200

4(40) = 160

40/4 = 10

27.

1 point

A population of scores has σ = 20. In this population, a score of X = 80 corresponds to z = +0.25. What is the population mean?

70

90

85

75

28.

1 point

In analysis of variance, the term factor refers to ____

a dependent variable

an independent (or quasi-independent) variable

a treatment total

a treatment mean

29.

1 point

The p value is a conditional probability, and represents ________.

The probability of finding the effect if the null hypothesis was true

The probability of not finding the effect if the null hypothesis was true

The probability of finding the effect if the null hypothesis was false

The probability of not finding the effect if the null hypothesis was true

30.

1 point

The Pearson correlation measures _____.

the degree to which the relationship is consistently one directional

the degree of curvilinear relationship

the degree of relationship without regard to the form of the relationship

the degree of linear relationship

31.

1 point

The results of a correlation analysis are as follows: r(72) = .56, p = .046. Calculate the coefficient of determination (R2):

31

44

56

0.046

32.

1 point

For which of the following situations would a repeated-measures research design be appropriate?

comparing verbal skills for girls versus boys at age 3

comparing pain tolerance before and after taking a new pain medication

comparing problem solving skills for science majors versus art majors at a college

comparing self-esteem for students who participate in school athletics versus those who do not

33.

1 point

Which of the following is the most appropriate description of a Type I error?

Reject the null hypothesis when it is true

Fail to reject the null hypothesis when it is true

Fail to reject the null hypothesis when it is false

Reject the null hypothesis when it is false

34.

1 point

A scatter plot shows a set of data points that are widely scattered around a line that slopes down to the right. Which of the following values would be closest to the correlation for these data?

0.40

0.80

-0.40

-0.80

35.

1 point

If the null hypothesis is true, on average the expected value for the related-samples t statistic is ____.

1

1.96

t>1.96

0

36.

1 point

A population of scores has μ = 42. In this population, an X value of 40 corresponds to z = -0.50. What is the population standard deviation?

-4

2

4

-2

37.

1 point

Under what circumstances is the experimentwise alpha level a concern?

whenever you do an analysis of variance

whenever an experiment involves more than one hypothesis test

whenever an experiment compares exactly two treatments

whenever the alpha level is greater than .05

38.

1 point

A researcher conducts an experiment and discovers a non-significant (p > .05) difference between her two experimental groups. What is the next step she should take?

Fail to accept the alternate hypothesis

Reject the null hypothesis

Fail to reject the null hypothesis

Accept the alternate hypothesis

39.

1 point

Run an independent samples t-test on the data file (Week8_Homework_Data.sav)

Has the assumption of Homogeneity of Variance (Levene’s test) been violated?

No: p > .05

Yes: p > .05

No: p < .05

Yes: p < .05

40.

1 point

Run an independent samples t-test on the data file (Week8_Homework_Data.sav).

What are the mean and SD for females?

6.26; 1.79

6.30; 1.50

6.27; 1.63

6.28; 1.47

41.

1 point

Under what circumstances would a score that is 15 points above the mean be considered an extreme score?

when the population standard deviation is much larger than 15

when the population mean is much smaller than 15

when the population mean is much larger than 15

when the population standard deviation is much smaller than 15

42.

1 point

The purpose for post tests is

to determine whether or not a Type I error was committed.

to determine which treatments are significantly different

none of the above

to determine how much difference exists between the treatments

43.

1 point

Which of the following research situations is most likely to use an independent-measures design?

Evaluate the difference in verbal skills between 3-year-old girls and 3-year-old boys

Evaluate the development of verbal skills between age 2 and age 3 for a sample of girls.

Evaluate the effectiveness of a diet program by measuring how much weight is lost during 4 weeks of dieting

Evaluate the effectiveness of a cholesterol medication by comparing cholesterol levels before and after the medication.

44.

1 point

Steven scores 55% on a Mathematics exam, and 74% on an Economics exam. Which is Steven's better subject in comparison with the others in his group if the group means and SDs are 50 and 4 (Mathematics) and 70 and 8 (Economics)?

Economics

He performed equally in both subjects

Mathematics

There is not enough information to calculate the answers

45.

1 point

A Pearson correlation of r = +1.00 between X and Y indicates _____.

every change in X causes a change in Y

every increase in X causes an increase in Y

All of the other 3 choices occur with a correlation of +1.00

each time X increases, there is a perfectly predictable increase in Y

46.

1 point

A research report describing the results from a repeated-measures study states, "The data showed a significant difference between treatments, t(22) = 4.71, p < .001." From this report you can conclude that the outcome of the hypothesis test was ____.

to fail to reject the null hypothesis

to make a Type II error

to make a Type I error

to reject the null hypothesis

47.

1 point

The Pearson correlation is calculated for a sample of n = 25 individuals. What value of df should be used to determine whether or not the correlation is significant?

25

23

cannot be determined without additional information

24

48.

1 point

A researcher reports t(24) = 5.30 for an independent-measures experiment. How many individuals participated in the entire experiment?

25

26

12

24

49.

1 point

A population of scores has μ = 44. In this population, an X value of 40 corresponds to z = -0.50. What is the population standard deviation?

6

8

2

4

50.

1 point

A research report describing the results from a repeated-measures study includes the following: "The data show no significant difference between the two treatments, t(10) = 1.65, p = .07." Based on this report, you can conclude that a total of ____ individuals participated in the research study .

9

10

11

12