Question 1

If the sample data are in the critical region with α = .01,then the same sample data would still be in the critical region if α were changed to .05.

Accepted Answer

A) True 
 B)False

Question 2

The null hypothesis is stated in terms of the population,even though the data come from a sample.

Accepted Answer

A) True 
 B)False

Question 3

Which of the following accurately describes a hypothesis test?​

Accepted Answer

A) ​A descriptive technique that allows researchers to describe a sample 
B) ​A descriptive technique that allows researchers to describe a population 
C) ​An inferential technique that uses the data from a sample to draw inferences about a population 
D) ​An inferential technique that uses information about a population to make predictions about a sample

Question 4

One of the simplest and most direct methods for measuring effect size is Cohen's
d.

Accepted Answer

A) True 
 B)False

Question 5

The alpha level determines the risk of a Type I error.

Accepted Answer

A) True 
 B)False

Question 6

A significant treatment effect does not necessarily indicate a large treatment effect.

Accepted Answer

A) True 
 B)False

Question 7

What is the consequence of a Type II error?​

Accepted Answer

A) ​Concluding that a treatment has an effect when it really does 
B) ​Concluding that a treatment has no effect when it really has no effect 
C) ​Concluding that a treatment has no effect when it really does 
D) ​Concluding that a treatment has an effect when it really has no effect

Question 8

In a research report,the notation p < .05 indicates that the probability of a Type I error is less than .05.

Accepted Answer

A) True 
 B)False

Question 9

If a treatment has a very small effect,then what is a likely outcome for a hypothesis test evaluating the treatment?​

Accepted Answer

A) ​A Type I error 
B) ​A Type II error 
C) ​Correctly reject the null hypothesis 
D) ​Correctly fail to reject the null hypothesis

Question 10

If α is held constant at .05,what is the impact of changing the sample size on the critical region and the risk of a Type I error?​

Accepted Answer

A) ​As sample size increases, the critical region expands and the risk of a Type I error increases. 
B) ​As sample size increases, the critical region shrinks and the risk of a Type I error increases. 
C) ​As sample size increases, the critical region expands and the risk of a Type I error decreases. 
D) ​As the sample size increases, the critical region, and the risk of a Type I error remain unchanged.

Question 11

A research report includes the statement,z = 2.13,p < .05.For this hypothesis test,the used null hypothesis is rejected using an alpha level of α = .05.

Accepted Answer

A) True 
 B)False

Question 12

A Type I error occurs when a researcher concludes that a treatment has an effect but,in fact,the treatment has no effect.

Accepted Answer

A) True 
 B)False

Question 13

Which of the following is an accurate definition of a Type II error?​​

Accepted Answer

A) ​Rejecting a false null hypothesis 
B) ​Rejecting a true null hypothesis 
C) ​Failing to reject a false null hypothesis 
D) ​Failing to reject a true null hypothesis

Question 14

Some researchers claim that herbal supplements such as ginseng or ginkgo biloba enhance human memory.To test this claim,a researcher selects a sample of n = 25 college students.Each student is given a ginkgo biloba supplement daily for six weeks and then all the participants are given a standardized memory test.For the population,scores on the test are normally distributed with μ = 70 and σ = 15.The sample of n = 25 students had a mean score of M = 75.
a. Are the data sufficient to that the herb has a significant effect on memory? Use a two-tailed test with α = .05.
b. Compute Cohen's d for this study.

Accepted Answer

The answer of Some researchers claim that herbal supplements such...

Question 15

If the sample data are in the critical region with α = .05,then the same sample data would still be in the critical region if α were changed to .01.

Accepted Answer

A) True 
 B)False

Question 16

A researcher is testing the effectiveness of a new herbal supplement that claims to improve physical fitness.A sample of n = 16 college students is obtained and each student takes the supplement daily for six weeks.At the end of the 6-week period,each student is given a standardized fitness test and the average score for the sample is M = 39.For the general population of college students,the distribution of test scores is normal with a mean of µ = 35 and a standard deviation of σ = 12.Do students taking the supplement have significantly better fitness scores? Use a one-tailed test with α = .05.

Accepted Answer

The answer of A researcher is testing the effectiveness of...

Question 17

A researcher administers a treatment to a sample from a population with a mean of m = 60.If the treatment is expected to increase scores and a one-tailed test is used to evaluate the treatment effect,then the null hypothesis states that m 60.

Accepted Answer

A) True 
 B)False

Question 18

A researcher administers a treatment to a sample of participants selected from a population with µ = 80.If the researcher obtains a sample mean of M = 88,given the same alpha level,which combination of factors is most likely to result in rejecting the null hypothesis?​

Accepted Answer

A) ​σ = 5 and n = 25 
B) ​σ = 5 and n = 50 
C) ​σ = 10 and n = 25 
D) ​σ = 10 and n = 50

Question 19

You can reduce the risk of a Type I error by using a larger sample.

Accepted Answer

A) True 
 B)False

Question 20

Which of the following accurately describes the critical region?​

Accepted Answer

A) ​Outcomes with a very low probability if the null hypothesis is true 
B) ​Outcomes with a high probability if the null hypothesis is true 
C) ​Outcomes with a very low probability whether or not the null hypothesis is true 
D) ​Outcomes with a high probability whether or not the null hypothesis is true

Exam 8: Introduction to Hypothesis Testing

If the sample data are in the critical region with α = .01,then the same sample data would still be in the critical region if α were changed to .05.

The null hypothesis is stated in terms of the population,even though the data come from a sample.

Which of the following accurately describes a hypothesis test?​

One of the simplest and most direct methods for measuring effect size is Cohen's d.

The alpha level determines the risk of a Type I error.

A significant treatment effect does not necessarily indicate a large treatment effect.

What is the consequence of a Type II error?​

In a research report,the notation p < .05 indicates that the probability of a Type I error is less than .05.

If a treatment has a very small effect,then what is a likely outcome for a hypothesis test evaluating the treatment?​

If α is held constant at .05,what is the impact of changing the sample size on the critical region and the risk of a Type I error?​

A research report includes the statement,z = 2.13,p < .05.For this hypothesis test,the used null hypothesis is rejected using an alpha level of α = .05.

A Type I error occurs when a researcher concludes that a treatment has an effect but,in fact,the treatment has no effect.

Which of the following is an accurate definition of a Type II error?​​

If the sample data are in the critical region with α = .05,then the same sample data would still be in the critical region if α were changed to .01.

A researcher administers a treatment to a sample from a population with a mean of m = 60.If the treatment is expected to increase scores and a one-tailed test is used to evaluate the treatment effect,then the null hypothesis states that m 60.

A researcher administers a treatment to a sample of participants selected from a population with µ = 80.If the researcher obtains a sample mean of M = 88,given the same alpha level,which combination of factors is most likely to result in rejecting the null hypothesis?​

You can reduce the risk of a Type I error by using a larger sample.

Which of the following accurately describes the critical region?​

Which of the following accurately describes a hypothesis test?

What is the consequence of a Type II error?

If a treatment has a very small effect,then what is a likely outcome for a hypothesis test evaluating the treatment?

If α is held constant at .05,what is the impact of changing the sample size on the critical region and the risk of a Type I error?

Which of the following is an accurate definition of a Type II error?

A researcher administers a treatment to a sample of participants selected from a population with µ = 80.If the researcher obtains a sample mean of M = 88,given the same alpha level,which combination of factors is most likely to result in rejecting the null hypothesis?

Which of the following accurately describes the critical region?