Exam 11: Inferences About Population Variances

A large company has claimed that the standard deviation of the monthly incomes of their employees is less than or equal to $120. To test their claim, a random sample of 76 employees of the company was taken; and it was determined that the standard deviation of their incomes was $135. At 90% confidence, test the company's claim.

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Question 41

The president of a bank believes that the variance of the deposits of suburban customers is more than the variance of city customers. Below you are given the results of samples taken from suburban and city customers. a.State the null and alternative hypotheses to be tested. b.Compute the test statistic. c.Determine the p-value. d.At 95% confidence, what do you conclude?

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Question 42

Exhibit 11-3 The contents of a sample of 26 cans of apple juice showed a standard deviation of 0.06 ounces. We are interested in testing to determine whether the variance of the population is significantly more than 0.003. -Refer to Exhibit 11-3. At 95% confidence, the null hypothesis

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Question 43

An egg packing company has stated that the standard deviation of the weights of their grade A large eggs is 0.07 ounces or less. The sample variance for 51 eggs was 0.0065 ounces. Can this sample result confirm the company's claim? Use $\alpha$ = 0.1.

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Question 44

A sample of 21 elements is selected to estimate a 90% confidence interval for the variance of the population. The chi-square value(s) to be used for this interval estimation is (are)

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Question 45

It has been suggested that night shift-workers show more variability in their output levels than day workers. Below, you are given the results of two independent random samples. a.State the null and alternative hypotheses to be tested. b.Compute the test statistic. c.Determine the p-value. d.At 95% confidence, what do you conclude?

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Question 46

Exhibit 11-6 We want to test the hypothesis that the population variances are equal. -Refer to Exhibit 11-6. At 95% confidence, the null hypothesis

(Multiple Choice)

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Question 47

A sample of 41 observations yielded a sample standard deviation of 5. If we want to test H₀: $\sigma$ ² = 20, the test statistic is

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Question 48

A sample of 15 items provides a sample mean of 18 and a sample variance of 16. Compute a 95% confidence interval estimate for the standard deviation of the population.

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Question 49

The 99% confidence interval estimate for a population variance when a sample standard deviation of 12 is obtained from a sample of 10 items is

(Multiple Choice)

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Question 50

A sample of 30 items provided a sample mean of 28 and a sample standard deviation of 6. Test the following hypotheses using $\alpha$ = 0.05. What is your conclusion? $A sample of 30 items provided a sample mean of 28 and a sample standard deviation of 6. Test the following hypotheses using \alpha = 0.05. What is your conclusion?$

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Question 51

Exhibit 11-8 -Refer to Exhibit 11-8. The null hypothesis

(Multiple Choice)

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Question 52

Exhibit 11-8 -Refer to Exhibit 11-8. If the test is to be performed at 95% confidence, the critical value(s) from the table is(are)

(Multiple Choice)

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Question 53

A sample of 61 items provided a sample mean of 932, a sample mode of 900, and a sample standard deviation of 11. Test the following hypotheses using $\alpha$ = 0.05. What is your conclusion? $A sample of 61 items provided a sample mean of 932, a sample mode of 900, and a sample standard deviation of 11. Test the following hypotheses using \alpha = 0.05. What is your conclusion?$

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Question 54

Exhibit 11-3 The contents of a sample of 26 cans of apple juice showed a standard deviation of 0.06 ounces. We are interested in testing to determine whether the variance of the population is significantly more than 0.003. -Refer to Exhibit 11-3. The null hypothesis is

(Multiple Choice)

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Question 55

To avoid the problem of not having access to tables of the F distribution with values given for the lower tail when a two-tailed test is required, let the smaller sample variance be

(Multiple Choice)

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Question 56

Exhibit 11-4 -Refer to Exhibit 11-4. The test statistic for this problem equals

(Multiple Choice)

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Question 57

Exhibit 11-3 The contents of a sample of 26 cans of apple juice showed a standard deviation of 0.06 ounces. We are interested in testing to determine whether the variance of the population is significantly more than 0.003. -Refer to Exhibit 11-3. The p-value for this test is

(Multiple Choice)

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Question 58

A random sample of 25 employees of a local utility firm showed that their monthly incomes had a sample standard deviation of $112. Provide a 90% confidence interval estimate for the standard deviation of the incomes for all the firm's employees.

(Short Answer)

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Question 59

Exhibit 11-6 We want to test the hypothesis that the population variances are equal. -Refer to Exhibit 11-6. The p-value is between

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Question 60

Showing 41 - 60 of 90

Exhibit 11-3 The contents of a sample of 26 cans of apple juice showed a standard deviation of 0.06 ounces. We are interested in testing to determine whether the variance of the population is significantly more than 0.003. -Refer to Exhibit 11-3. At 95% confidence, the null hypothesis

An egg packing company has stated that the standard deviation of the weights of their grade A large eggs is 0.07 ounces or less. The sample variance for 51 eggs was 0.0065 ounces. Can this sample result confirm the company's claim? Use $\alpha$ = 0.1.

A sample of 21 elements is selected to estimate a 90% confidence interval for the variance of the population. The chi-square value(s) to be used for this interval estimation is (are)

Exhibit 11-6 We want to test the hypothesis that the population variances are equal. -Refer to Exhibit 11-6. At 95% confidence, the null hypothesis

A sample of 41 observations yielded a sample standard deviation of 5. If we want to test H₀: $\sigma$ ² = 20, the test statistic is

A sample of 15 items provides a sample mean of 18 and a sample variance of 16. Compute a 95% confidence interval estimate for the standard deviation of the population.

The 99% confidence interval estimate for a population variance when a sample standard deviation of 12 is obtained from a sample of 10 items is

Exhibit 11-8 -Refer to Exhibit 11-8. The null hypothesis

Exhibit 11-8 -Refer to Exhibit 11-8. If the test is to be performed at 95% confidence, the critical value(s) from the table is(are)

Exhibit 11-3 The contents of a sample of 26 cans of apple juice showed a standard deviation of 0.06 ounces. We are interested in testing to determine whether the variance of the population is significantly more than 0.003. -Refer to Exhibit 11-3. The null hypothesis is

To avoid the problem of not having access to tables of the F distribution with values given for the lower tail when a two-tailed test is required, let the smaller sample variance be

Exhibit 11-4 -Refer to Exhibit 11-4. The test statistic for this problem equals

Exhibit 11-3 The contents of a sample of 26 cans of apple juice showed a standard deviation of 0.06 ounces. We are interested in testing to determine whether the variance of the population is significantly more than 0.003. -Refer to Exhibit 11-3. The p-value for this test is

A random sample of 25 employees of a local utility firm showed that their monthly incomes had a sample standard deviation of $112. Provide a 90% confidence interval estimate for the standard deviation of the incomes for all the firm's employees.

Exhibit 11-6 We want to test the hypothesis that the population variances are equal. -Refer to Exhibit 11-6. The p-value is between

Data and Statistics

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Descriptive Statistics: Numerical Measures

Introduction to Probability

Discrete Probability Distributions

Continuous Probability Distributions

Sampling and Sampling Distributions

Interval Estimation

Hypothesis Tests

Inference About Means and Proportions With Two Populations

Comparing Multiple Proportions, Test of Independence and Goodness of Fit

Experimental Design and Analysis of Variance

Simple Linear Regression

Multiple Regression

Regression Analysis: Model Building

Time Series Analysis and Forecasting

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Exam 11: Inferences About Population Variances

Exhibit 11-3 The contents of a sample of 26 cans of apple juice showed a standard deviation of 0.06 ounces. We are interested in testing to determine whether the variance of the population is significantly more than 0.003. -Refer to Exhibit 11-3. At 95% confidence, the null hypothesis

An egg packing company has stated that the standard deviation of the weights of their grade A large eggs is 0.07 ounces or less. The sample variance for 51 eggs was 0.0065 ounces. Can this sample result confirm the company's claim? Use α\alphaα = 0.1.

A sample of 21 elements is selected to estimate a 90% confidence interval for the variance of the population. The chi-square value(s) to be used for this interval estimation is (are)

Exhibit 11-6 We want to test the hypothesis that the population variances are equal. -Refer to Exhibit 11-6. At 95% confidence, the null hypothesis

A sample of 41 observations yielded a sample standard deviation of 5. If we want to test H0: σ\sigmaσ 2 = 20, the test statistic is

A sample of 15 items provides a sample mean of 18 and a sample variance of 16. Compute a 95% confidence interval estimate for the standard deviation of the population.

The 99% confidence interval estimate for a population variance when a sample standard deviation of 12 is obtained from a sample of 10 items is

A sample of 30 items provided a sample mean of 28 and a sample standard deviation of 6. Test the following hypotheses using α\alphaα = 0.05. What is your conclusion?

Exhibit 11-8 -Refer to Exhibit 11-8. The null hypothesis

Exhibit 11-8 -Refer to Exhibit 11-8. If the test is to be performed at 95% confidence, the critical value(s) from the table is(are)

A sample of 61 items provided a sample mean of 932, a sample mode of 900, and a sample standard deviation of 11. Test the following hypotheses using α\alphaα = 0.05. What is your conclusion?

Exhibit 11-3 The contents of a sample of 26 cans of apple juice showed a standard deviation of 0.06 ounces. We are interested in testing to determine whether the variance of the population is significantly more than 0.003. -Refer to Exhibit 11-3. The null hypothesis is

To avoid the problem of not having access to tables of the F distribution with values given for the lower tail when a two-tailed test is required, let the smaller sample variance be

Exhibit 11-4 -Refer to Exhibit 11-4. The test statistic for this problem equals

Exhibit 11-3 The contents of a sample of 26 cans of apple juice showed a standard deviation of 0.06 ounces. We are interested in testing to determine whether the variance of the population is significantly more than 0.003. -Refer to Exhibit 11-3. The p-value for this test is

A random sample of 25 employees of a local utility firm showed that their monthly incomes had a sample standard deviation of $112. Provide a 90% confidence interval estimate for the standard deviation of the incomes for all the firm's employees.

Exhibit 11-6 We want to test the hypothesis that the population variances are equal. -Refer to Exhibit 11-6. The p-value is between

Data and Statistics

Descriptive Statistics: Tabular and Graphical Displays

Descriptive Statistics: Numerical Measures

Introduction to Probability

Discrete Probability Distributions

Continuous Probability Distributions

Sampling and Sampling Distributions

Interval Estimation

Hypothesis Tests

Inference About Means and Proportions With Two Populations

Comparing Multiple Proportions, Test of Independence and Goodness of Fit

Experimental Design and Analysis of Variance

Simple Linear Regression

Multiple Regression

Regression Analysis: Model Building

Time Series Analysis and Forecasting

Nonparametric Methods

Statistical Methods for Quality Control

Index Numbers

Decision Analysis on Website

Sample Survey on Website

Filters

An egg packing company has stated that the standard deviation of the weights of their grade A large eggs is 0.07 ounces or less. The sample variance for 51 eggs was 0.0065 ounces. Can this sample result confirm the company's claim? Use $\alpha$ = 0.1.

A sample of 41 observations yielded a sample standard deviation of 5. If we want to test H₀: $\sigma$ ² = 20, the test statistic is