Question 1

If σ12 = 10 and σ22 = 5, when will the robustness of the assumptions underlying the t-test be in jeopardy? (Consider Type I error only.)

Accepted Answer

A)  When mean1/mean2= 2 
B)  When N1/N2= 3 
C)  When mean2/mean1= 2 
D)  When N2/N1= 3 
A)  When mean1/mean2= 2 
B)  When N1/N2= 3 
C)  When mean2/mean1= 2 
D)  When N2/N1= 3

Question 2

What does the significance level (alpha level) protect against doing incorrectly?

Accepted Answer

A)  Rejecting the alternative hypothesis 
B)  Rejecting the null hypothesis 
C)  Failing to reject the null hypothesis 
D)  Either rejecting or failing to reject the null hypothesis 
A)  Rejecting the alternative hypothesis 
B)  Rejecting the null hypothesis 
C)  Failing to reject the null hypothesis 
D)  Either rejecting or failing to reject the null hypothesis

Question 3

If the alpha is changed from 0.10 to 0.05, what happens to the chances of a Type I and a Type II error, respectively?

Accepted Answer

A)  Increases, decreases 
B)  Decreases, decreases 
C)  Increases, increases 
D)  Decreases, increases 
A)  Increases, decreases 
B)  Decreases, decreases 
C)  Increases, increases 
D)  Decreases, increases

Question 4

The simplest experimental design has how many independent variables, with how many levels, and how many dependent variables?
 
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Accepted Answer

The answer of The simplest experimental design has how many...

Question 5

What percentage of change of the treatment group over the control group is suggested by an effect size of 1.2?

Accepted Answer

A)  11.3% 
B)  38.5% 
C)  40.3% 
D)  88.5% 
A)  11.3% 
B)  38.5% 
C)  40.3% 
D)  88.5%

Question 6

Researchers set alpha at a relatively small level to avoid which of the following errors?

Accepted Answer

A)  Rejecting the null hypothesis when it is false 
B)  Retaining the null hypothesis when it is false 
C)  Rejecting the null hypothesis when it is true 
D)  Retaining the null hypothesis when it is true 
A)  Rejecting the null hypothesis when it is false 
B)  Retaining the null hypothesis when it is false 
C)  Rejecting the null hypothesis when it is true 
D)  Retaining the null hypothesis when it is true

Question 7

When is it impossible to commit a Type I error?

Accepted Answer

A)  When the null hypothesis is actually false 
B)  When N is very large 
C)  When the experimenter rejects the null hypothesis 
D)  It is always possible. 
A)  When the null hypothesis is actually false 
B)  When N is very large 
C)  When the experimenter rejects the null hypothesis 
D)  It is always possible.

Question 8

For which significance level (or alpha) would the chance of making a Type I error be the greatest when H0 is rejected?

Accepted Answer

A)  0.25 
B)  0.10 
C)  0.01 
D)  0.001 
A)  0.25 
B)  0.10 
C)  0.01 
D)  0.001

Question 9

The t-ratio required for significance for a one-tailed test at the .05 level is the same as for a two-tailed test at what level?

Accepted Answer

A)  .01 
B)  .05 
C)  .10 
D)  .20 
A)  .01 
B)  .05 
C)  .10 
D)  .20

Question 10

Which procedure would reduce the power of a statistical test?

Accepted Answer

A)  Using a one-tailed test instead of a two-tailed test 
B)  Reducing the variability of the scores 
C)  Changing the alpha level from .10 to .05 
D)  Decreasing the sample size 
A)  Using a one-tailed test instead of a two-tailed test 
B)  Reducing the variability of the scores 
C)  Changing the alpha level from .10 to .05 
D)  Decreasing the sample size

Question 11

Use the following information to answer the question: The purpose of the research was to determine whether cholesterol level is related to lifestyle behaviors. The lifestyle behaviors of interest were physical activity, dietary fat intake, smoking status, and self-reported life satisfaction. The researchers rejected the null hypothesis. Assume that the researchers are interested in differences between genders. They conclude p < .001 for genders. What does this mean?

Accepted Answer

A)  The genders differ. 
B)  The genders do not differ. 
C)  There might be a Type II error. 
D)  More than one of the above 
A)  The genders differ. 
B)  The genders do not differ. 
C)  There might be a Type II error. 
D)  More than one of the above

Question 12

What is an effect size?

Accepted Answer

A)  A z-score 
B)  A value to help interpret meaningfulness 
C)  The difference between two means expressed in standard deviation units 
D)  All of the above 
A)  A z-score 
B)  A value to help interpret meaningfulness 
C)  The difference between two means expressed in standard deviation units 
D)  All of the above

Question 13

Why is a dependent t-test usually more powerful than an independent t-test?

Accepted Answer

A)  The denominator is smaller 
B)  The denominator is larger 
C)  The numerator is smaller 
D)  The numerator is larger 
A)  The denominator is smaller 
B)  The denominator is larger 
C)  The numerator is smaller 
D)  The numerator is larger

Question 14

A researcher concluded that the null hypothesis was tenable (could be defended). What error has possibly been committed, and what is the probability of committing it?

Accepted Answer

A)  Type I, alpha level 
B)  Type II, alpha level 
C)  Type I, cannot determine 
D)  Type II, cannot determine 
A)  Type I, alpha level 
B)  Type II, alpha level 
C)  Type I, cannot determine 
D)  Type II, cannot determine

Question 15

A 2 x 5 between-groups experimental design has how many different treatment conditions?

Accepted Answer

A)  1 
B)  2 
C)  5 
D)  10 
A)  1 
B)  2 
C)  5 
D)  10

Question 16

If a researcher used an independent t-test but should have used a dependent t-test, which errors are most likely?

Accepted Answer

A)  SE of the mean is too small, Type II 
B)  SE of the mean is too large, Type I 
C)  SE of the mean is too small, Type I 
D)  SE of the mean is too large, Type II 
A)  SE of the mean is too small, Type II 
B)  SE of the mean is too large, Type I 
C)  SE of the mean is too small, Type I 
D)  SE of the mean is too large, Type II

Question 17

What does p < .05 indicate?

Accepted Answer

A)  It depends on what the research hypothesis is 
B)  The null hypothesis (H0) is tenable 
C)  The null (H0) hypothesis should be rejected 
D)  A Type I error has occurred 
E)  None of the above 
A)  It depends on what the research hypothesis is 
B)  The null hypothesis (H0) is tenable 
C)  The null (H0) hypothesis should be rejected 
D)  A Type I error has occurred 
E)  None of the above

Question 18

Use the following information to answer the question: The purpose of the research was to determine whether cholesterol level is related to lifestyle behaviors. The lifestyle behaviors of interest were physical activity, dietary fat intake, smoking status, and self-reported life satisfaction. The researchers rejected the null hypothesis. What was the primary independent variable in this study?

Accepted Answer

A)  Smoking status 
B)  Physical activity 
C)  Risk for elevated cholesterol 
D)  Gender 
E)  Lifestyle behaviors 
A)  Smoking status 
B)  Physical activity 
C)  Risk for elevated cholesterol 
D)  Gender 
E)  Lifestyle behaviors

Question 19

If α = .05, β = .15, N =100, and S = 25, what is the power?

Accepted Answer

A)  .95 
B)  .85 
C)  .75 
D)  .05 
A)  .95 
B)  .85 
C)  .75 
D)  .05

Question 20

Which of the following would a researcher be LEAST likely to use to examine the practical difference between two sample means?

Accepted Answer

A)  The population mean 
B)  Effect size 
C)  Omega squared 
D)  Percent improvement 
A)  The population mean 
B)  Effect size 
C)  Omega squared 
D)  Percent improvement

If σ₁² = 10 and σ₂² = 5, when will the robustness of the assumptions underlying the t-test be in jeopardy? (Consider Type I error only.)

What does the significance level (alpha level) protect against doing incorrectly?

If the alpha is changed from 0.10 to 0.05, what happens to the chances of a Type I and a Type II error, respectively?

The simplest experimental design has how many independent variables, with how many levels, and how many dependent variables? a. b. c. d. IVs 1 2 1 2 Levels 1 2 2 1 DV 1 2 1 2

What percentage of change of the treatment group over the control group is suggested by an effect size of 1.2?

Researchers set alpha at a relatively small level to avoid which of the following errors?

When is it impossible to commit a Type I error?

For which significance level (or alpha) would the chance of making a Type I error be the greatest when H₀ is rejected?

The t-ratio required for significance for a one-tailed test at the .05 level is the same as for a two-tailed test at what level?

Which procedure would reduce the power of a statistical test?

What is an effect size?

Why is a dependent t-test usually more powerful than an independent t-test?

A researcher concluded that the null hypothesis was tenable (could be defended). What error has possibly been committed, and what is the probability of committing it?

A 2 x 5 between-groups experimental design has how many different treatment conditions?

If a researcher used an independent t-test but should have used a dependent t-test, which errors are most likely?

What does p < .05 indicate?

If α = .05, β = .15, N =100, and S = 25, what is the power?

Which of the following would a researcher be LEAST likely to use to examine the practical difference between two sample means?

Research Methods

Introduction to Measurement and Statistics

Descriptive Statistics

The Normal Curve and Standard Scores

Correlation and Regression

Introduction to Inferential Statistics

Two-Sample T-Test

One-Way Between-Groups Anova

One-Way Within-Groups Anova

Factorial Anova

Multivariate Anova Manova

Advanced Statistics

Nonparametric Statistics

Filters

Exam 8: Issues in Inferential Statistics

If σ12 = 10 and σ22 = 5, when will the robustness of the assumptions underlying the t-test be in jeopardy? (Consider Type I error only.)

What does the significance level (alpha level) protect against doing incorrectly?

If the alpha is changed from 0.10 to 0.05, what happens to the chances of a Type I and a Type II error, respectively?

The simplest experimental design has how many independent variables, with how many levels, and how many dependent variables? a. b. c. d. IVs 1 2 1 2 Levels 1 2 2 1 DV 1 2 1 2

What percentage of change of the treatment group over the control group is suggested by an effect size of 1.2?

Researchers set alpha at a relatively small level to avoid which of the following errors?

When is it impossible to commit a Type I error?

For which significance level (or alpha) would the chance of making a Type I error be the greatest when H0 is rejected?

The t-ratio required for significance for a one-tailed test at the .05 level is the same as for a two-tailed test at what level?

Which procedure would reduce the power of a statistical test?

What is an effect size?

Why is a dependent t-test usually more powerful than an independent t-test?

A researcher concluded that the null hypothesis was tenable (could be defended). What error has possibly been committed, and what is the probability of committing it?

A 2 x 5 between-groups experimental design has how many different treatment conditions?

If a researcher used an independent t-test but should have used a dependent t-test, which errors are most likely?

What does p < .05 indicate?

If α = .05, β = .15, N =100, and S = 25, what is the power?

Which of the following would a researcher be LEAST likely to use to examine the practical difference between two sample means?

Research Methods

Introduction to Measurement and Statistics

Descriptive Statistics

The Normal Curve and Standard Scores

Correlation and Regression

Introduction to Inferential Statistics

Two-Sample T-Test

One-Way Between-Groups Anova

One-Way Within-Groups Anova

Factorial Anova

Multivariate Anova Manova

Advanced Statistics

Nonparametric Statistics

Filters

If σ₁² = 10 and σ₂² = 5, when will the robustness of the assumptions underlying the t-test be in jeopardy? (Consider Type I error only.)

For which significance level (or alpha) would the chance of making a Type I error be the greatest when H₀ is rejected?