Question 1

Which statement is NOT true?

Accepted Answer

A) Rejecting the null hypothesis when it is true is a Type I error. 
B) The probability of making a Type I error is symbolized by α. 
C) Failing to reject the null hypothesis when it is false is a Type I error. 
D) Type II error can occur for both one and two-tailed tests. 
A) Rejecting the null hypothesis when it is true is a Type I error. 
B) The probability of making a Type I error is symbolized by α. 
C) Failing to reject the null hypothesis when it is false is a Type I error. 
D) Type II error can occur for both one and two-tailed tests.

Question 2

The t value for a 99% confidence interval estimation based upon a sample of size 10 is

Accepted Answer

A) 1.645. 
B) 1.812. 
C) 2.576. 
D) 3.169. 
A) 1.645. 
B) 1.812. 
C) 2.576. 
D) 3.169.

Question 3

The CEO of a company wants to estimate the percent of employees that use company computers to go on Facebook during work hours with 95% confidence. He selects a random sample of 150 of the employees and finds that 53 of them logged onto Facebook that day. What is the estimate of the standard error of the proportion proportion $\sigma _ { \bar { p } }$ ?

Accepted Answer

A) 0.039 
B) 0.050 
C) 0.350 
D) 0.455 
A) 0.039 
B) 0.050 
C) 0.350 
D) 0.455

Question 4

A Type I error is committed when

Accepted Answer

A) a true alternative hypothesis is not accepted. 
B) a true null hypothesis is rejected. 
C) the critical value is greater than the value of the test statistic. 
D) the validity of a claim was rejected. 
A) a true alternative hypothesis is not accepted. 
B) a true null hypothesis is rejected. 
C) the critical value is greater than the value of the test statistic. 
D) the validity of a claim was rejected.

Question 5

The medical director of a company looks at the medical records of all 50 employees and finds that the mean systolic blood pressure for these employees is 126.07. The value of 126.07 is symbolized by

Accepted Answer

The answer of The medical director of a company looks...

Question 6

The finite correction factor should be used in the computation of the standard deviation of the sample mean and the standard population when n / N is

Accepted Answer

A) greater than 0.05. 
B) greater than 0.5. 
C) less than 0.05. 
D) less than 0.5. 
A) greater than 0.05. 
B) greater than 0.5. 
C) less than 0.05. 
D) less than 0.5.

Question 7

A pizza shop advertises that they deliver in 30 minutes or less or it is free. People who live in homes that are located on the opposite side of town believe it will take the pizza shop longer than 30 minutes to make and deliver the pizza. A random sample of 50 deliveries to homes across town was taken and the mean time was computed to be 32 minutes. What is the appropriate symbol to represent the value, 32?

Accepted Answer

A) u = 32 
B)  $\bar { x }$ = 32 
C) n = 32 
D)  $\bar { p }$ = 32 
A) u = 32 
B)  $\bar { x }$ = 32 
C) n = 32 
D)  $\bar { p }$ = 32

Question 8

In a random sample of 400 registered voters, 120 indicated they plan to vote for Trump for President. Determine a 95% confidence interval for the proportion of all the registered voters who will vote for Trump.

Accepted Answer

A) (0.25, 0.34) 
B) (0.27, 0.32) 
C) (0.29, 0.30) 
D) Cannot be determined from the information given. 
A) (0.25, 0.34) 
B) (0.27, 0.32) 
C) (0.29, 0.30) 
D) Cannot be determined from the information given.

Question 9

An estimate of a population parameter that provides an interval of values believed to contain the value of the parameter is known as the

Accepted Answer

A) confidence level. 
B) interval estimate. 
C) parameter level. 
D) population estimate. 
A) confidence level. 
B) interval estimate. 
C) parameter level. 
D) population estimate.

Question 10

Two approaches to drawing a conclusion in a hypothesis test are

Accepted Answer

A) p-value and critical value. 
B) one-tailed and two-tailed. 
C) Type I and Type II. 
D) null and alternative. 
A) p-value and critical value. 
B) one-tailed and two-tailed. 
C) Type I and Type II. 
D) null and alternative.

Question 11

Determine whether the alternative hypothesis is left-tailed, right-tailed, or two-tailed: H0: μ = 11, Ha: μ > 11.

Accepted Answer

A) Left-tailed 
B) Right-tailed 
C) Two-tailed 
D) There is not enough information to make a determination. 
A) Left-tailed 
B) Right-tailed 
C) Two-tailed 
D) There is not enough information to make a determination.

Question 12

A large manufacturing plant has analyzed the amount of time required to produce an electrical part and determined that the times follow a normal distribution with mean time ? = 45 hours. The production manager has developed a new procedure for producing the part. He believes that the new procedure will decrease the population mean amount of time required to produce the part. After training a group of production line workers, a random sample of 25 parts will be selected and the average amount of time required to produce them will be determined. If the switch is made to the new procedure, the cost to implement the new procedure will be more than offset by the savings in manpower required to produce the parts. Use the hypotheses: H0: ? ? 45 hours and Ha: ? < 45 hours. If the sample mean amount of time is $\bar { x }$ = 43.118 hours with the sample standard deviation s = 5.5 hours, give the appropriate conclusion, for ? = 0.025. ?

Accepted Answer

A) Do not reject H0, do not switch to the new procedure. 
B) Reject H0, switch to the new procedure. 
C) Reject H0, do not switch to the new procedure. 
D) Do not reject H0, switch to the new procedure. 
A) Do not reject H0, do not switch to the new procedure. 
B) Reject H0, switch to the new procedure. 
C) Reject H0, do not switch to the new procedure. 
D) Do not reject H0, switch to the new procedure.

Question 13

If the expected value of the sample statistic is equal to the population parameter being estimated, the sample statistic is said to

Accepted Answer

A) have low variability. 
B) be an unbiased estimator of the population parameter. 
C) have high precision. 
D) be a random estimator of the population parameter. 
A) have low variability. 
B) be an unbiased estimator of the population parameter. 
C) have high precision. 
D) be a random estimator of the population parameter.

Question 14

The value of the ___________ is used to estimate the value of the population parameter.

Accepted Answer

A) population statistic 
B) sample parameter 
C) population estimate 
D) sample statistic 
A) population statistic 
B) sample parameter 
C) population estimate 
D) sample statistic

Question 15

The CEO of a company wants to estimate the percent of employees that use company computers to go on Facebook during work hours with 95% confidence. He selects a random sample of 150 of the employees and finds that 53 of them logged onto Facebook that day. Compute the 95% confidence interval for the population proportion.

Accepted Answer

A)  $0.35 \pm 1.96 \sqrt { \frac { 0.35 ( 1 - 0.35 ) } { 150 } }$ 
B)  $0.35 \pm 1.645 \sqrt { \frac { 0.35 ( 1 - 0.35 ) } { 150 } }$ 
C)  $0.53 \pm 1.645 \sqrt { \frac { 0.53 ( 1 - 0.53 ) } { 150 } }$ 
D)  $0.53 \pm 1.96 \sqrt { \frac { 0.53 ( 1 - 0.53 ) } { 150 } }$ 
A)  $0.35 \pm 1.96 \sqrt { \frac { 0.35 ( 1 - 0.35 ) } { 150 } }$ 
B)  $0.35 \pm 1.645 \sqrt { \frac { 0.35 ( 1 - 0.35 ) } { 150 } }$ 
C)  $0.53 \pm 1.645 \sqrt { \frac { 0.53 ( 1 - 0.53 ) } { 150 } }$ 
D)  $0.53 \pm 1.96 \sqrt { \frac { 0.53 ( 1 - 0.53 ) } { 150 } }$

Question 16

For a population with an unknown distribution, the form of the sampling distribution of the sample mean is

Accepted Answer

A) approximately normal for small sample sizes. 
B) exactly normal for large sample sizes. 
C) exactly normal for small sample sizes. 
D) approximately normal for large sample sizes. 
A) approximately normal for small sample sizes. 
B) exactly normal for large sample sizes. 
C) exactly normal for small sample sizes. 
D) approximately normal for large sample sizes.

Question 17

The average number of hours for a random sample of mail order pharmacists from company A was 50.1 hours last year. It is believed that changes to medical insurance have led to a reduction in the average work week. To test the validity of this belief, the hypotheses are

Accepted Answer

A) H0: u > 50.1, Ha: u 0: u = 50.1, Ha: u = 50.1. C) H0: u ≤ 50.1, Ha: u > 50.1. D) H0: u ≥ 50.1, Ha: u < 50.1. A) H0: u > 50.1, Ha: u 0: u = 50.1, Ha: u = 50.1. C) H0: u ≤ 50.1, Ha: u > 50.1. D) H0: u ≥ 50.1, Ha: u < 50.1.

Question 18

A statistics teacher started class one day by drawing the names of 10 students out of a hat and asked them to do as many pushups as they could. The 10 randomly selected students averaged 15 pushups per person with a standard deviation of 9 pushups. Suppose the distribution of the population of number of pushups that can be done is approximately normal. What is the standard error of the mean?

Accepted Answer

A) 0.900 
B) 2.876 
C) 3.061 
D) 4.743 
A) 0.900 
B) 2.876 
C) 3.061 
D) 4.743

Question 19

A statistics teacher started class one day by drawing the names of 10 students out of a hat and asked them to do as many pushups as they could. The 10 randomly selected students averaged 15 pushups per person with a standard deviation of 9 pushups. Suppose the distribution of the population of number of pushups that can be done is approximately normal. The 95% confidence interval for the true mean number of pushups that can be done is ​

Accepted Answer

A) 5.75 to 24.25. 
B) 8.56 to 21.40. 
C) 11.31 to 18.55. 
D) 13.02 to 16.98. 
A) 5.75 to 24.25. 
B) 8.56 to 21.40. 
C) 11.31 to 18.55. 
D) 13.02 to 16.98.

Question 20

A sample of 37 AA batteries had a mean lifetime of 584 hours. A 95% confidence interval for the population mean was 579.2 < μ < 588.8. Which statement is the correct interpretation of the results?

Accepted Answer

A) We are 95% confident that the mean lifetime of all the bulbs in the population is between 579.2 hours and 588.8 hours. 
B) The probability that the population mean is between 579.2 hours and 588.8 hours is 0.95. 
C) 95% of the light bulbs in the sample had lifetimes between 579.2 hours and 588.8 hours. 
D) None of these statements correctly interpret the results. 
A) We are 95% confident that the mean lifetime of all the bulbs in the population is between 579.2 hours and 588.8 hours. 
B) The probability that the population mean is between 579.2 hours and 588.8 hours is 0.95. 
C) 95% of the light bulbs in the sample had lifetimes between 579.2 hours and 588.8 hours. 
D) None of these statements correctly interpret the results.

Which statement is NOT true?

The t value for a 99% confidence interval estimation based upon a sample of size 10 is

A Type I error is committed when

The medical director of a company looks at the medical records of all 50 employees and finds that the mean systolic blood pressure for these employees is 126.07. The value of 126.07 is symbolized by

The finite correction factor should be used in the computation of the standard deviation of the sample mean and the standard population when n / N is

In a random sample of 400 registered voters, 120 indicated they plan to vote for Trump for President. Determine a 95% confidence interval for the proportion of all the registered voters who will vote for Trump.

An estimate of a population parameter that provides an interval of values believed to contain the value of the parameter is known as the

Two approaches to drawing a conclusion in a hypothesis test are

Determine whether the alternative hypothesis is left-tailed, right-tailed, or two-tailed: H₀: μ = 11, H_a: μ > 11.

If the expected value of the sample statistic is equal to the population parameter being estimated, the sample statistic is said to

The value of the ___________ is used to estimate the value of the population parameter.

For a population with an unknown distribution, the form of the sampling distribution of the sample mean is

The average number of hours for a random sample of mail order pharmacists from company A was 50.1 hours last year. It is believed that changes to medical insurance have led to a reduction in the average work week. To test the validity of this belief, the hypotheses are

A sample of 37 AA batteries had a mean lifetime of 584 hours. A 95% confidence interval for the population mean was 579.2 < μ < 588.8. Which statement is the correct interpretation of the results?

Introduction

Descriptive Statistics

Data Visualization

Descriptive Data Mining

Probability: an Introduction to Modeling Uncertainty

Linear Regression

Time Series Analysis and Forecasting

Predictive Data Mining

Spreadsheet Models

Monte Carlo Simulation

Linear Optimization Models

Integer Linear Optimization Models

Nonlinear Optimization Models

Decision Analysis

Filters

Exam 6: Statistical Inference

Which statement is NOT true?

The t value for a 99% confidence interval estimation based upon a sample of size 10 is

A Type I error is committed when

The medical director of a company looks at the medical records of all 50 employees and finds that the mean systolic blood pressure for these employees is 126.07. The value of 126.07 is symbolized by

The finite correction factor should be used in the computation of the standard deviation of the sample mean and the standard population when n / N is

In a random sample of 400 registered voters, 120 indicated they plan to vote for Trump for President. Determine a 95% confidence interval for the proportion of all the registered voters who will vote for Trump.

An estimate of a population parameter that provides an interval of values believed to contain the value of the parameter is known as the

Two approaches to drawing a conclusion in a hypothesis test are

Determine whether the alternative hypothesis is left-tailed, right-tailed, or two-tailed: H0: μ = 11, Ha: μ > 11.

If the expected value of the sample statistic is equal to the population parameter being estimated, the sample statistic is said to

The value of the ___________ is used to estimate the value of the population parameter.

For a population with an unknown distribution, the form of the sampling distribution of the sample mean is

The average number of hours for a random sample of mail order pharmacists from company A was 50.1 hours last year. It is believed that changes to medical insurance have led to a reduction in the average work week. To test the validity of this belief, the hypotheses are

A sample of 37 AA batteries had a mean lifetime of 584 hours. A 95% confidence interval for the population mean was 579.2 < μ < 588.8. Which statement is the correct interpretation of the results?

Introduction

Descriptive Statistics

Data Visualization

Descriptive Data Mining

Probability: an Introduction to Modeling Uncertainty

Linear Regression

Time Series Analysis and Forecasting

Predictive Data Mining

Spreadsheet Models

Monte Carlo Simulation

Linear Optimization Models

Integer Linear Optimization Models

Nonlinear Optimization Models

Decision Analysis

Filters

Determine whether the alternative hypothesis is left-tailed, right-tailed, or two-tailed: H₀: μ = 11, H_a: μ > 11.