Question 1

If the calculated value of the test statistic for a two-sided test is Z = 1.84,then the p-value is 0.0329.

Accepted Answer

A) True 
 B)False

Question 2

The Next Questions Are Based On The Following Information:
An engineering research center claims that,through the use of a new computer control system,automobiles should achieve,on average,at least an additional 5 miles per gallon of gas.A random sample of 81 automobiles was used to evaluate this product.The sample mean increase in miles per gallon achieved was 4.5,and the sample standard deviation was 2.9 miles per gallon.
-Test the hypothesis at the 5% level.

Accepted Answer

Reject H₀ if t < -t_∞_,.05 = -1.645 t = @#IMG-DLM& = -1.55

Question 3

The significance level and the probability of a Type I error are equivalent.

Accepted Answer

A) True 
 B)False

Question 4

Differentiate between a one-sided and two-sided composite alternative hypothesis when the null hypothesis is H0 : μ = 10?

Accepted Answer

When the null hypothesis is H₀ : μ = 10,a

Question 5

THE Next Questions Are Based On The Following Information:
A large milling machine produces steel rods to certain specifications.The machine is considered to be running normally if the standard deviation of the diameter of the rods is at most 0.15 millimeters.The line supervisor needs to test the machine is for normal functionality.The quality inspector takes a sample of 25 rods and finds that the sample standard deviation is 0.19.
-What are the null and alternative hypotheses for the test?

Accepted Answer

A) H0 : σ2 > 0.15 and H1 : σ2 ≤ 0.15 
B) H0 : σ ≥ 0.15 and H1 : σ 0 : σ = 0.0225 and H1 : σ ≠ 0.0225 
D) H0 : σ2 ≤ 0.0225 and H1 : σ2 > 0.0225 
A) H0 : σ2 > 0.15 and H1 : σ2 ≤ 0.15 
B) H0 : σ ≥ 0.15 and H1 : σ 0 : σ = 0.0225 and H1 : σ ≠ 0.0225 
D) H0 : σ2 ≤ 0.0225 and H1 : σ2 > 0.0225

Question 6

Thomas is a shift manager at a local fast food place,and is responsible for quality management.Thomas wants to ensure that all the frozen hamburger patties that get delivered by the supplier weigh four ounces on average.Assume that the standard deviation of the weight of hamburger patties is known to be 0.1 ounces.Thomas tells one of his employees that as a shipment arrives,select 25 patties at random and find the average weight for the 25 patties.For what average weight would you tell the employee to reject the shipment,if you wanted the probability of a Type I error to be 0.10 or less?

Accepted Answer

H₀ : μ = 4.0 against H₁ : μ < 4.0 Reject H

Question 7

The Next Questions Are Based On The Following Information:
A hydraulic press is operating correctly when the standard deviation of the pressure is less than 120 pounds-per-square-inch (psi).Suppose you take a random sample of 15 measurements throughout the day of the psi and find the standard deviation to be 148.Suppose you want to test whether the press is operating correctly.
-Suppose you have the following null and alternative hypotheses: H0 : σ2 = 34.5 and H1 : σ2 > 34.5.If you take a random sample of 15 observations from a normally distributed population and find that s2 = 48.1,what is the most accurate statement that can be made about the p-value for this test?

Accepted Answer

A) 0)01 < p-value < 0.025 
B) 0)025 < p-value < 0.05 
C) p-value < 0.01 
D) 0)05 < p-value < 0.10 
A) 0)01 < p-value < 0.025 
B) 0)025 < p-value < 0.05 
C) p-value < 0.01 
D) 0)05 < p-value < 0.10

Question 8

The Next Questions Are Based On The Following Information:
A beer producer claims that the proportion of its customers who cannot distinguish regular from light beer is at most 12 percent.The producer decides to test this null hypothesis against the alternative that the true proportion is more than 12 percent.The decision rule adopted is to reject the null hypothesis if the sample proportion of who cannot distinguish between the two beers exceeds 15 percent.
-If a random sample of 100 customers is chosen,what is the probability of a Type I error,using this decision rule?

Accepted Answer

H₀ : P ≤ 0.12 and H₁ : P > 0.12

Question 9

The Next Questions Are Based On The Following Information:
Before agreeing to purchase a large order of polyethylene sheaths for a particular type of high pressure oil-filled submarine power cable,a company wants to see conclusive evidence that the true standard deviation of sheath thickness is less than .05 inches.
-What hypotheses should be tested,and why?

Accepted Answer

Let σ denote the population standard dev

Question 10

The Next Questions Are Based On The Following Information:
The manufacturer of a new chewing gum claims that at least 80% of dentists surveyed prefer their type of gum and recommend it for their patients who chew gum.An independent consumer research firm decides to test their claim.The findings in a sample of 200 dentists indicate that 74.1% of the respondents do actually prefer their gum.
-Which of the following statements is most accurate?

Accepted Answer

A) Fail to reject the null hypothesis at α ≤ 0.10 
B) Reject the null hypothesis at α = 0.05 
C) Reject the null hypothesis at α = 0.10,but not 0.05 
D) Reject the null hypothesis at α = 0.01 
A) Fail to reject the null hypothesis at α ≤ 0.10 
B) Reject the null hypothesis at α = 0.05 
C) Reject the null hypothesis at α = 0.10,but not 0.05 
D) Reject the null hypothesis at α = 0.01

Question 11

The Next Questions Are Based On The Following Information:
A hydraulic press is operating correctly when the standard deviation of the pressure is less than 120 pounds-per-square-inch (psi).Suppose you take a random sample of 15 measurements throughout the day of the psi and find the standard deviation to be 148.Suppose you want to test whether the press is operating correctly.
-What are the appropriate null and alternative hypotheses?

Accepted Answer

A) H0 : σ2 = 1202 and H1 : σ2 > 1202 
B) H0 : σ = 120 and H1 : σ 0 : σ = 120 and H1 : σ ≠ 120 
D) H0 : σ2 > 120 and H1 : σ2 ≤ 120 
A) H0 : σ2 = 1202 and H1 : σ2 > 1202 
B) H0 : σ = 120 and H1 : σ 0 : σ = 120 and H1 : σ ≠ 120 
D) H0 : σ2 > 120 and H1 : σ2 ≤ 120

Question 12

The Next Questions Are Based On The Following Information:
A company selling new econometrics computer software advertises that firms using this software obtain,on average during the first year,a yield of at least 10% on their initial investments.A random sample of 10 of the franchises that used the software produced the following yields for the first year of operation: 9.4,11.1,10.4,10.5,11.2,8.2,8.5,4.0,8.8,and 6.1.Assume that population yields are normally distributed.
-How does variance affect hypothesis testing in most applied situations?

Accepted Answer

In most applied situations,and especiall

Question 13

A fitness club claims that the average age of its members is 42.Assume that the ages are normally distributed.You believe that the average age is less than 42,therefore,you ask the ages of a few of the fitness club's members and get the following values: 40,55,50,33,38,35,30,and 45.Do you have any reason at the 10 per cent level of significance to think the fitness club's claim is incorrect?

Accepted Answer

H₀ : μ = 42 against H₁ : μ < 42 The sample

Question 14

Suppose that you want to test H0 : P = 0.25 against H1: P ≠ 0.25.The test statistic is:

Accepted Answer

A) (   
- P0)/
   
B) (p - P0)/   
C) (   
- P0)/
   
D) (p - P0)/ [(P0)(1 - P0)/ n] 
A) (   
- P0)/
   
B) (p - P0)/   
C) (   
- P0)/
   
D) (p - P0)/ [(P0)(1 - P0)/ n]

Question 15

The Next Questions Are Based On The Following Information:
The sales representative for a manufacturer of a new product claims that the product will increase output per machine by at least 29 units per hour.A line manager installs the product on 15 of the machines,and finds that the average increase was only 26 with a standard deviation of 6.2.
-Which of the following is true of confidence intervals in hypothesis tests of the variance of a normal population,where variances are smaller than anticipated?

Accepted Answer

A) It will always result in a negative value. 
B) It will meet anticipated levels. 
C) It will be wider than anticipated. 
D) It will be narrower than anticipated. 
A) It will always result in a negative value. 
B) It will meet anticipated levels. 
C) It will be wider than anticipated. 
D) It will be narrower than anticipated.

Question 16

The Next Questions Are Based On The Following Information:
A hydraulic press is operating correctly when the standard deviation of the pressure is less than 120 pounds-per-square-inch (psi).Suppose you take a random sample of 15 measurements throughout the day of the psi and find the standard deviation to be 148.Suppose you want to test whether the press is operating correctly.
-When testing H0 : μ = 50 against H1 : μ ≠ 50,where would the rejection region fall for this hypothesis test?

Accepted Answer

A) in the left tail 
B) in the right tail 
C) in both the left and right tails 
D) at point zero 
A) in the left tail 
B) in the right tail 
C) in both the left and right tails 
D) at point zero

Question 17

The Next Questions Are Based On The Following Information:
A hydraulic press is operating correctly when the standard deviation of the pressure is less than 120 pounds-per-square-inch (psi).Suppose you take a random sample of 15 measurements throughout the day of the psi and find the standard deviation to be 148.Suppose you want to test whether the press is operating correctly.
-Which of the following is true of the p-value?

Accepted Answer

A) It is the probability of rejecting the null hypothesis when the null hypothesis is true. 
B) It is the smallest significance level at which a null hypothesis can be rejected. 
C) It is the probability of rejecting the null hypothesis when the alternative hypothesis is true. 
D) It is the extreme value of the test statistic obtained when the alternative hypothesis is true. 
A) It is the probability of rejecting the null hypothesis when the null hypothesis is true. 
B) It is the smallest significance level at which a null hypothesis can be rejected. 
C) It is the probability of rejecting the null hypothesis when the alternative hypothesis is true. 
D) It is the extreme value of the test statistic obtained when the alternative hypothesis is true.

Question 18

Suppose that a test procedure about the population proportion P is performed,and that the sample proportion   
is approximately normally distributed.If the alternative hypothesis is H1 : P 0,then the rejection region for a level α is Z α.

Accepted Answer

A) True 
 B)False

Question 19

THE Next Questions Are Based On The Following Information:
A large milling machine produces steel rods to certain specifications.The machine is considered to be running normally if the standard deviation of the diameter of the rods is at most 0.15 millimeters.The line supervisor needs to test the machine is for normal functionality.The quality inspector takes a sample of 25 rods and finds that the sample standard deviation is 0.19.
-Which of the following statements is the most accurate?

Accepted Answer

A) Reject null hypothesis at α = 0.025 
B) Fail to reject null hypothesis at α ≤ 0.10 
C) Reject null hypothesis at α = 0.05 
D) Reject null hypothesis at α = 0.01 
A) Reject null hypothesis at α = 0.025 
B) Fail to reject null hypothesis at α ≤ 0.10 
C) Reject null hypothesis at α = 0.05 
D) Reject null hypothesis at α = 0.01

Question 20

The Next Questions Are Based On The Following Information:
The marketing department for a hand calculator claims the battery pack performs 20,000 calculations before it has to be recharged.The quality control manager for the manufacturer is entrusted with validating the claim that the battery pack works as long as the specifications state in order to secure a large order from a key customer.A test of 114 battery packs yields an average of 19,695 calculations with a standard deviation of 1,103.
-How is the p-value computed for a two-sided alternative given a null hypothesis H0 : μ = μ0 for the mean of a normal distribution with known variance?

Accepted Answer

The p-values can be computed by noting t

If the calculated value of the test statistic for a two-sided test is Z = 1.84,then the p-value is 0.0329.

The significance level and the probability of a Type I error are equivalent.

Differentiate between a one-sided and two-sided composite alternative hypothesis when the null hypothesis is H₀ : μ = 10?

Suppose that you want to test H₀ : P = 0.25 against H₁: P ≠ 0.25.The test statistic is:

Suppose that a test procedure about the population proportion P is performed,and that the sample proportion is approximately normally distributed.If the alternative hypothesis is H₁ : P < P₀,then the rejection region for a level α is Z < -z_α.

Describing Data: Graphical

Describing Data: Numerical

Probability

Discrete Random Variables and Probability Distributions

Continuous Random Variables and Probability Distributions

Sampling and Sampling Distributions

Estimation: Single Population

Estimation: Additional Topics

Hypothesis Testing: Additional Topics

Simple Regression

Multiple Regression

Additional Topics in Regression Analysis

Analysis of Categorical Data

Analysis of Variance

Time-Series Analysis and Forecasting

Additional Topics in Sampling

Filters

Exam 9: Hypothesis Testing: Single Population

If the calculated value of the test statistic for a two-sided test is Z = 1.84,then the p-value is 0.0329.

The significance level and the probability of a Type I error are equivalent.

Differentiate between a one-sided and two-sided composite alternative hypothesis when the null hypothesis is H0 : μ = 10?

Suppose that you want to test H0 : P = 0.25 against H1: P ≠ 0.25.The test statistic is:

Suppose that a test procedure about the population proportion P is performed,and that the sample proportion is approximately normally distributed.If the alternative hypothesis is H1 : P < P0,then the rejection region for a level α is Z < -zα.

Describing Data: Graphical

Describing Data: Numerical

Probability

Discrete Random Variables and Probability Distributions

Continuous Random Variables and Probability Distributions

Sampling and Sampling Distributions

Estimation: Single Population

Estimation: Additional Topics

Hypothesis Testing: Additional Topics

Simple Regression

Multiple Regression

Additional Topics in Regression Analysis

Analysis of Categorical Data

Analysis of Variance

Time-Series Analysis and Forecasting

Additional Topics in Sampling

Filters

Differentiate between a one-sided and two-sided composite alternative hypothesis when the null hypothesis is H₀ : μ = 10?

Suppose that you want to test H₀ : P = 0.25 against H₁: P ≠ 0.25.The test statistic is:

Suppose that a test procedure about the population proportion P is performed,and that the sample proportion is approximately normally distributed.If the alternative hypothesis is H₁ : P < P₀,then the rejection region for a level α is Z < -z_α.