Two independent samples selected from two normally distributed populations have variances of σ12 and σ22 with n1 = 10 and n2 = 15. The degrees of freedom for the F distribution when testing the equality of the two population variances are

A) 10 and 15. B) 11 and 16. C) 9 and 14. D) 8 and 13. A) 10 and 15. B) 11 and 16. C) 9 and 14. D) 8 and 13. C

In testing the difference between the means of two normally distributed populations, if μ1 = μ2 = 50, n1 = 9, and n2 = 13, the degrees of freedom for the t statistic equals ________.

A) 22 B) 21 C) 19 D) 20 A) 22 B) 21 C) 19 D) 20

Exam 11: Statistical Inferences Based on Two Samples

Two independent samples selected from two normally distributed populations have variances of σ₁² and σ₂² with n₁ = 10 and n₂ = 15. The degrees of freedom for the F distribution when testing the equality of the two population variances are

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Question 1

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A new company is in the process of evaluating its customer service. The company offers two types of sales: (1) Internet sales and (2) store sales. The marketing research manager believes that the Internet sales are more than 10 percent higher than store sales. The null hypothesis would be

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Question 2

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In an opinion survey, a random sample of 1,000 adults from the United States and 1,000 adults from Germany were asked whether they supported the death penalty. 590 American adults and 560 German adults indicated that they supported the death penalty. The researcher wants to know whether there is sufficient evidence to conclude that the proportion of adults who support the death penalty is higher in the United States than in Germany. What is the decision at α = .10?

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Question 3

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Reject the null hypothesis in favor of the alternate hypothesis. We have enough statistical evidence at the alpha equal to 0.1 level to state that the proportion of adults who support the death penalty in the USA is higher than in Germany.
H₀: ≤ H_A: > = = .59, = = .56 = = .575 = = .0221
Z = = 1.36
1.36 > 1.28, reject H₀.

Parameters of the F distribution include

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Question 4

In testing the equality of population variance, what assumption(s) should be considered?

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Question 5

What is the F statistic for testing H₀: σ₁² ≤ σ₂², H_A: σ₂² > σ₁² at α = .05, where n₁ = 16, n₂ = 19, s₁² = .03, and s₂² = .02?

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Question 6

In testing for the equality of means from two independent populations, if the hypothesis of equal population means is rejected at α = .01, it will ________ be rejected at α = .05.

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Question 7

Given the following information about a hypothesis test of the difference between two means based on independent random samples, what is the calculated value of the test statistic? Assume that the samples are obtained from normally distributed populations having equal variances. H_A: μ_A > μ_B, = 12, = 9, s₁ = 5, s₂ = 3, n₁ = 13, n₂ = 10.

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Question 8

In testing the equality of population variances, two assumptions are required: independent samples and normally distributed populations.

(True/False)

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Question 9

Find a 90 percent confidence interval for the difference between the proportions of failures in factory 1 and factory 2, where = .05, = .04, n₁ = 500, and n₂ = 2000.

(Short Answer)

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Question 10

Suppose that a realtor is interested in comparing the price of midrange homes in two cities in a midwestern state. She conducts a small survey in the two cities, looking at the price of midrange homes. Assume equal population variances. Calculate the pooled estimate of σ² (rounded to nearest hundred).

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Question 11

A marketing research company surveyed grocery shoppers on the East Coast and West Coast to find the percentage of the customers who prefer chicken to other meat. The data are given below. The marketing research company is testing the hypothesis that the proportion of customers who prefer chicken is higher on the West Coast. Test at α = .05.

(Short Answer)

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Question 12

Assume that we are constructing a confidence interval for the difference in the means of two populations based on independent random samples. If both sample sizes n₁ and n₂ =10, and the distributions of both populations are highly skewed, then a confidence interval for the difference in the means can be constructed using the t test statistic.

(True/False)

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Question 13

In testing the difference between the means of two normally distributed populations, if μ₁ = μ₂ = 50, n₁ = 9, and n₂ = 13, the degrees of freedom for the t statistic equals ________.

(Multiple Choice)

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Question 14

A test of mathematical ability is given to a random sample of 10 eighth-grade students before and after they complete a semester-long basic mathematics course. The mean score before the course was 119.60, and after the course the mean score was 130.80. The standard deviation of the difference is 16.061. Calculate the test statistic to test the claim that scores were higher after the course.

(Short Answer)

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Question 15

Given the following information about a hypothesis, and the test of the difference between two variances based on independent random samples, what is the critical value of the test statistic at a significance level of 0.05? Assume that the samples are obtained from normally distributed populations. H_A: σ²_A > σ²_B, ₁ = 12, ₂ = 9, s₁ = 5, s₂ = 3, n₁ = 13, n₂ = 10.

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Question 16

Sample 1 has data: 16, 14, 19, 18, 19, 20, 15, 18, 17, 18; and sample 2 has data: 13, 19, 14, 17, 21, 14, 15, 10, 13, 15. Testing the equality of means at α = .05, can we reject the null hypothesis (using critical value rules)? (Assume equal population variances.)

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Question 17

If we are testing the hypothesis about the mean of a population of paired differences with samples of n₁ = 10, n₂ = 10, the degrees of freedom for the t statistic is ________.

(Multiple Choice)

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Question 18

In comparing the difference between two independent population means, the sampling distributions of the population means are at least approximately ________.

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Question 19

Suppose that a realtor is interested in comparing the price of midrange homes in two cities in a midwestern state. She conducts a small survey in the two cities, looking at the price of midrange homes. Assume equal population variances. Test the claim at α = .01.

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Question 20

Showing 1 - 20 of 140

Two independent samples selected from two normally distributed populations have variances of σ₁² and σ₂² with n₁ = 10 and n₂ = 15. The degrees of freedom for the F distribution when testing the equality of the two population variances are

A new company is in the process of evaluating its customer service. The company offers two types of sales: (1) Internet sales and (2) store sales. The marketing research manager believes that the Internet sales are more than 10 percent higher than store sales. The null hypothesis would be

Parameters of the F distribution include

In testing the equality of population variance, what assumption(s) should be considered?

What is the F statistic for testing H₀: σ₁² ≤ σ₂², H_A: σ₂² > σ₁² at α = .05, where n₁ = 16, n₂ = 19, s₁² = .03, and s₂² = .02?

In testing for the equality of means from two independent populations, if the hypothesis of equal population means is rejected at α = .01, it will ________ be rejected at α = .05.

In testing the equality of population variances, two assumptions are required: independent samples and normally distributed populations.

Find a 90 percent confidence interval for the difference between the proportions of failures in factory 1 and factory 2, where = .05, = .04, n₁ = 500, and n₂ = 2000.

In testing the difference between the means of two normally distributed populations, if μ₁ = μ₂ = 50, n₁ = 9, and n₂ = 13, the degrees of freedom for the t statistic equals ________.

Sample 1 has data: 16, 14, 19, 18, 19, 20, 15, 18, 17, 18; and sample 2 has data: 13, 19, 14, 17, 21, 14, 15, 10, 13, 15. Testing the equality of means at α = .05, can we reject the null hypothesis (using critical value rules)? (Assume equal population variances.)

If we are testing the hypothesis about the mean of a population of paired differences with samples of n₁ = 10, n₂ = 10, the degrees of freedom for the t statistic is ________.

In comparing the difference between two independent population means, the sampling distributions of the population means are at least approximately ________.

Suppose that a realtor is interested in comparing the price of midrange homes in two cities in a midwestern state. She conducts a small survey in the two cities, looking at the price of midrange homes. Assume equal population variances. Test the claim at α = .01.

An Introduction to Business Statistics and Analytics

Descriptive Statistics and Analytics: Tabular and Graphical Methods

Descriptive Statistics and Analytics: Numerical Methods

Probability and Probability Models

Predictive Analytics I: Trees, K-Nearest Neighbors, Naive Bayes,

Discrete Random Variables

Continuous Random Variables

Sampling Distributions

Confidence Intervals

Hypothesis Testing

Experimental Design and Analysis of Variance

Chi-Square Tests

Simple Linear Regression Analysis

Multiple Regression and Model Building

Predictive Analytics Ii: Logistic Regression, Discriminate Analysis,

Time Series Forecasting and Index Numbers

Nonparametric Methods

Decision Theory

Filters

Exam 11: Statistical Inferences Based on Two Samples

Two independent samples selected from two normally distributed populations have variances of σ12 and σ22 with n1 = 10 and n2 = 15. The degrees of freedom for the F distribution when testing the equality of the two population variances are

A new company is in the process of evaluating its customer service. The company offers two types of sales: (1) Internet sales and (2) store sales. The marketing research manager believes that the Internet sales are more than 10 percent higher than store sales. The null hypothesis would be

Parameters of the F distribution include

In testing the equality of population variance, what assumption(s) should be considered?

What is the F statistic for testing H0: σ12 ≤ σ22, HA: σ22 > σ12 at α = .05, where n1 = 16, n2 = 19, s12 = .03, and s22 = .02?

In testing for the equality of means from two independent populations, if the hypothesis of equal population means is rejected at α = .01, it will ________ be rejected at α = .05.

In testing the equality of population variances, two assumptions are required: independent samples and normally distributed populations.

Find a 90 percent confidence interval for the difference between the proportions of failures in factory 1 and factory 2, where = .05, = .04, n1 = 500, and n2 = 2000.

In testing the difference between the means of two normally distributed populations, if μ1 = μ2 = 50, n1 = 9, and n2 = 13, the degrees of freedom for the t statistic equals ________.

Sample 1 has data: 16, 14, 19, 18, 19, 20, 15, 18, 17, 18; and sample 2 has data: 13, 19, 14, 17, 21, 14, 15, 10, 13, 15. Testing the equality of means at α = .05, can we reject the null hypothesis (using critical value rules)? (Assume equal population variances.)

If we are testing the hypothesis about the mean of a population of paired differences with samples of n1 = 10, n2 = 10, the degrees of freedom for the t statistic is ________.

In comparing the difference between two independent population means, the sampling distributions of the population means are at least approximately ________.

Suppose that a realtor is interested in comparing the price of midrange homes in two cities in a midwestern state. She conducts a small survey in the two cities, looking at the price of midrange homes. Assume equal population variances. Test the claim at α = .01.

An Introduction to Business Statistics and Analytics

Descriptive Statistics and Analytics: Tabular and Graphical Methods

Descriptive Statistics and Analytics: Numerical Methods

Probability and Probability Models

Predictive Analytics I: Trees, K-Nearest Neighbors, Naive Bayes,

Discrete Random Variables

Continuous Random Variables

Sampling Distributions

Confidence Intervals

Hypothesis Testing

Experimental Design and Analysis of Variance

Chi-Square Tests

Simple Linear Regression Analysis

Multiple Regression and Model Building

Predictive Analytics Ii: Logistic Regression, Discriminate Analysis,

Time Series Forecasting and Index Numbers

Nonparametric Methods

Decision Theory

Filters

Two independent samples selected from two normally distributed populations have variances of σ₁² and σ₂² with n₁ = 10 and n₂ = 15. The degrees of freedom for the F distribution when testing the equality of the two population variances are

What is the F statistic for testing H₀: σ₁² ≤ σ₂², H_A: σ₂² > σ₁² at α = .05, where n₁ = 16, n₂ = 19, s₁² = .03, and s₂² = .02?

Find a 90 percent confidence interval for the difference between the proportions of failures in factory 1 and factory 2, where = .05, = .04, n₁ = 500, and n₂ = 2000.

In testing the difference between the means of two normally distributed populations, if μ₁ = μ₂ = 50, n₁ = 9, and n₂ = 13, the degrees of freedom for the t statistic equals ________.

If we are testing the hypothesis about the mean of a population of paired differences with samples of n₁ = 10, n₂ = 10, the degrees of freedom for the t statistic is ________.