Question 1

The test for the mean difference in a matched pairs design requires the differences to have a(n) ____________________ distribution.

Accepted Answer

The answer of The test for the mean difference in...

Question 2

In testing for the equality of two population variances, when the populations are normally distributed, the 10% level of significance has been used.To determine the rejection region, it will be necessary to refer to the F table corresponding to an upper-tail area of:

Accepted Answer

A)  .90 
B)  .20 
C)  .10 
D)  .05 
A)  .90 
B)  .20 
C)  .10 
D)  .05

Question 3

To estimate the ratio of the population variances you use the ____________________ of the ____________________ variances.

Accepted Answer

The answer of To estimate the ratio of the population...

Question 4

Antioxidants
A food processor wants to compare two antioxidants for their effects on retarding spoilage.Suppose 16 cuts of fresh meat are treated with antioxidant A and 16 are treated with antioxidant B, and the number of hours until spoilage begins is recorded for each of the 32 cuts of meat.The results are summarized in the table below
  
-{Antioxidants Narrative} State the null and alternative hypotheses for determining if the population variances differ for Antioxidants A and B.

Accepted Answer

The answer of Antioxidants
A food processor wants to compare two...

Question 5

The test statistic for testing for the equality of two population variances has a(n) ____________________ distribution.

Accepted Answer

The answer of The test statistic for testing for the...

Question 6

When the necessary conditions are met, a two-tail test is being conducted at $\alpha$ = .05 to test   .The two sample variances are   and   , and the sample sizes are n1 = 25 and n2 = 25.The calculated value of the test statistic will be F = 2.

Accepted Answer

A) True 
 B)False

Question 7

A calculus professor wanted to test whether the grades on calculus test were the same for upper and lower classmen.The professor took a random sample of size 12 from each group.For this situation, the professor should use a matched pairs t-test.

Accepted Answer

A) True 
 B)False

Question 8

When two population variances are ____________________ we estimate each population variance with its sample variance.The test statistic of   is approximately Student t-distributed with n1 + n2 - 2 degrees of freedom.

Accepted Answer

Question 9

In comparing two population means the statistic under consideration is   .

Accepted Answer

A) True 
 B)False

Question 10

The test statistic employed to test   is   is F-distributed with v1 = n1 - 1 and v2 = n2-1 degrees of freedom if the two populations are F-distributed.

Accepted Answer

A) True 
 B)False

Question 11

In comparing the difference in means with a matched pairs experiment, the variable under consideration is   , where the subscript D refers to the difference.

Accepted Answer

A) True 
 B)False

Question 12

Undergraduates' Test Scores
35 undergraduate students who completed two years of college were asked to take a basic mathematics test.The mean and standard deviation of their scores were 75.1 and 12.8, respectively.In a random sample of 50 students who only completed high school, the mean and standard deviation of the test scores were 72.1 and 14.6, respectively.
-{Undergraduates' Test Scores Narrative} Estimate with 90% confidence the difference in mean scores between the two groups of students.

Accepted Answer

3.0 @#IMG-DLM&4.98.T

Question 13

Unless we can conclude that the population variances are equal, we cannot use the pooled variance estimate.

Accepted Answer

A) True 
 B)False

Question 14

When testing   vs.   , the observed value of the z-score was found to be-2.15.Then, the p-value for this test would be

Accepted Answer

A)  .0158 
B)  .0316 
C)  .9842 
D)  .9684 
A)  .0158 
B)  .0316 
C)  .9842 
D)  .9684

Question 15

Additives
A food processor wants to compare two additives for their effects on retarding spoilage.Suppose 16 cuts of fresh meat are treated with additive A and 16 are treated with additive B, and the number of hours until spoilage begins is recorded for each of the 32 cuts of meat.The results are summarized in the table below
  
-{Additives Narrative} Assume population variances are equal.Calculate the pooled variance and the value of the test statistic.

Accepted Answer

The answer of Additives
A food processor wants to compare two...

Question 16

Engine Wear
To compare the wearing of two types of automobile engines, 1 and 2, an experimenter chose to "pair" the measurements, comparing the wear for the two types of engines on each of 7 automobiles, as shown below.
  
-{Engine Wear Narrative} Estimate with 90% confidence the mean difference and interpret.

Accepted Answer

-1.0 @#IMG-DLM& 1.587.Thus, LCL =-2.587, and UCL =

Question 17

The ratio of two independent chi-squared variables divided by their degrees of freedom is:

Accepted Answer

A)  normally distributed 
B)  Student t-distributed 
C)  chi-squared distributed 
D)  F-distributed 
A)  normally distributed 
B)  Student t-distributed 
C)  chi-squared distributed 
D)  F-distributed

Question 18

A political analyst in Iowa surveys a random sample of registered Republicans and compares the results with those obtained from a random sample of registered Democrats .This would be an example of two independent samples.

Accepted Answer

A) True 
 B)False

Question 19

Aptitude Test Scores
Two random samples of 40 students were drawn independently from two populations of students.Assume their aptitude tests are normally distributed (total points = 100).The following statistics regarding their scores in an aptitude test were obtained:   .
-{Aptitude Test Scores Narrative} Explain how to use the 95% confidence interval to test the hypotheses at $\alpha$= .05.

Accepted Answer

Since the hypothesized value 0

Question 20

When comparing two population means using data that are gathered from a matched pairs experiment, the test statistic for $\mu$D is Student t-distributed with v = nD -1 degrees of freedom, provided that the differences are normally distributed.

Accepted Answer

A) True 
 B)False

The test for the mean difference in a matched pairs design requires the differences to have a(n) ____________________ distribution.

In testing for the equality of two population variances, when the populations are normally distributed, the 10% level of significance has been used.To determine the rejection region, it will be necessary to refer to the F table corresponding to an upper-tail area of:

To estimate the ratio of the population variances you use the of the variances.

The test statistic for testing for the equality of two population variances has a(n) ____________________ distribution.

A calculus professor wanted to test whether the grades on calculus test were the same for upper and lower classmen.The professor took a random sample of size 12 from each group.For this situation, the professor should use a matched pairs t-test.

When two population variances are ____________________ we estimate each population variance with its sample variance.The test statistic of is approximately Student t-distributed with n₁ + n₂ - 2 degrees of freedom.

In comparing two population means the statistic under consideration is .

The test statistic employed to test is is F-distributed with v₁ = n₁ - 1 and v₂ = n₂-1 degrees of freedom if the two populations are F-distributed.

In comparing the difference in means with a matched pairs experiment, the variable under consideration is , where the subscript D refers to the difference.

Unless we can conclude that the population variances are equal, we cannot use the pooled variance estimate.

When testing vs. , the observed value of the z-score was found to be-2.15.Then, the p-value for this test would be

The ratio of two independent chi-squared variables divided by their degrees of freedom is:

A political analyst in Iowa surveys a random sample of registered Republicans and compares the results with those obtained from a random sample of registered Democrats .This would be an example of two independent samples.

When comparing two population means using data that are gathered from a matched pairs experiment, the test statistic for $\mu$ _D is Student t-distributed with v = n_D -1 degrees of freedom, provided that the differences are normally distributed.

What Is Statistics

Graphical Descriptive Techniques I

Graphical Descriptive Techniques II

Numerical Descriptive Techniques

Data Collection and Sampling

Probability

Random Variables and Discrete Probability Distributions

Continuous Probability Distributions

Sampling Distributions

Introduction to Estimation

Introduction to Hypothesis Testing

Inference About a Population

Analysis of Variance

Chi-Squared Tests

Simple Linear Regression and Correlation

Multiple Regression

Filters

Exam 13: Inference About Comparing Two Populations

The test for the mean difference in a matched pairs design requires the differences to have a(n) ____________________ distribution.

In testing for the equality of two population variances, when the populations are normally distributed, the 10% level of significance has been used.To determine the rejection region, it will be necessary to refer to the F table corresponding to an upper-tail area of:

To estimate the ratio of the population variances you use the ____________________ of the ____________________ variances.

The test statistic for testing for the equality of two population variances has a(n) ____________________ distribution.

When the necessary conditions are met, a two-tail test is being conducted at α\alphaα = .05 to test .The two sample variances are and , and the sample sizes are n1 = 25 and n2 = 25.The calculated value of the test statistic will be F = 2.

A calculus professor wanted to test whether the grades on calculus test were the same for upper and lower classmen.The professor took a random sample of size 12 from each group.For this situation, the professor should use a matched pairs t-test.

When two population variances are ____________________ we estimate each population variance with its sample variance.The test statistic of is approximately Student t-distributed with n1 + n2 - 2 degrees of freedom.

In comparing two population means the statistic under consideration is .

The test statistic employed to test is is F-distributed with v1 = n1 - 1 and v2 = n2-1 degrees of freedom if the two populations are F-distributed.

In comparing the difference in means with a matched pairs experiment, the variable under consideration is , where the subscript D refers to the difference.

Unless we can conclude that the population variances are equal, we cannot use the pooled variance estimate.

When testing vs. , the observed value of the z-score was found to be-2.15.Then, the p-value for this test would be

The ratio of two independent chi-squared variables divided by their degrees of freedom is:

A political analyst in Iowa surveys a random sample of registered Republicans and compares the results with those obtained from a random sample of registered Democrats .This would be an example of two independent samples.

When comparing two population means using data that are gathered from a matched pairs experiment, the test statistic for μ\muμ D is Student t-distributed with v = nD -1 degrees of freedom, provided that the differences are normally distributed.

What Is Statistics

Graphical Descriptive Techniques I

Graphical Descriptive Techniques II

Numerical Descriptive Techniques

Data Collection and Sampling

Probability

Random Variables and Discrete Probability Distributions

Continuous Probability Distributions

Sampling Distributions

Introduction to Estimation

Introduction to Hypothesis Testing

Inference About a Population

Analysis of Variance

Chi-Squared Tests

Simple Linear Regression and Correlation

Multiple Regression

Filters

To estimate the ratio of the population variances you use the of the variances.

When two population variances are ____________________ we estimate each population variance with its sample variance.The test statistic of is approximately Student t-distributed with n₁ + n₂ - 2 degrees of freedom.

The test statistic employed to test is is F-distributed with v₁ = n₁ - 1 and v₂ = n₂-1 degrees of freedom if the two populations are F-distributed.

When comparing two population means using data that are gathered from a matched pairs experiment, the test statistic for $\mu$ _D is Student t-distributed with v = n_D -1 degrees of freedom, provided that the differences are normally distributed.