Question 1

The y-axis for a null distribution is probability values.

Accepted Answer

A) True 
 B)False

Question 2

There is a risk relating to P-values when we look at our data before deciding on a one-sided or two-sided test. Describe this risk with specific reference to the P-value we calculate if we do the wrong test.

Accepted Answer

The answer of There is a risk relating to P-values...

Question 3

When presenting your results in a research paper or report, which of the following is not one of the pieces of information you should always include?

Accepted Answer

A)  The P-value 
B)  The range of values 
C)  The sample size 
D)  The value of the test statistic

Question 4

Increasing the value of the significance level tends to do which of the following?

Accepted Answer

A)  Increases Type I error and increases Type II error 
B)  Increases Type I error and reduces Type II error 
C)  Reduces Type I error and increases Type II error 
D)  Reduces Type I error and reduces Type II error

Question 5

Which of the following statements is correct?

Accepted Answer

A)  Larger P-values will tend to give nonsignificant results. 
B)  Larger P-values will tend to give significant results. 
C)  Lower P-values will tend to give insignificant results. 
D)  Lower P-values will tend to give unsignificant results.

Question 6

Describe the relationship between a statistical hypothesis and a scientific hypothesis.

Accepted Answer

The answer of Describe the relationship between a statistical hypothesis...

Question 7

The sampling distribution for a test statistic if the null hypothesis is true is called which of the following?

Accepted Answer

A)  The hypothetical distribution 
B)  The null distribution 
C)  The test distribution 
D)  The true distribution

Question 8

The power of a statistical test is best described as which of the following?

Accepted Answer

A)  The probability that the test will correctly accept a false alternative hypothesis. 
B)  The probability that the test will correctly accept a false null hypothesis. 
C)  The probability that the test will correctly reject a false alternative hypothesis. 
D)  The probability that the test will correctly reject a false null hypothesis.

Question 9

In your own words, describe what a P-value is and how we use it to evaluate statistical hypotheses.

Accepted Answer

The answer of In your own words, describe what a...

Question 10

Consider a hypothetical study in which ecologists looked at the sex ratios of clutches of frog eggs. In their sample, there were more clutches with a majority of males compared to those with a majority of females. The P-value of their test was 0.08. What is their best conclusion based on the evidence provided?

Accepted Answer

A)  The frequencies of male and female majority clutches seem to differ in the population. 
B)  The frequencies of male and female majority clutches don't seem to differ in the population. 
C)  There are more female majority clutches than male majority clutches in the population. 
D)  There are more male majority clutches than female majority clutches in the population.

Question 11

Nonsignificant tests are uninformative.

Accepted Answer

A) True 
 B)False

Question 12

Describe the major problem with using a nonsignificant result as evidence that the null hypothesis is true.

Accepted Answer

The answer of Describe the major problem with using a...

Question 13

Which of the following is the best description of what a "two-sided" test means?

Accepted Answer

A)  Either the null or alternative hypothesis may be false. 
B)  Either the null or alternative hypothesis may be true. 
C)  The alternative hypothesis includes parameter values of both sides of the null hypothesis parameter value. 
D)  The alternative hypothesis includes statistical values of both sides of the null hypothesis statistic value

Question 14

Consider a situation in which we calculate a 95% confidence interval that ranges from 18 to 23. If we conducted a two-sided test with the null hypothesis of the population mean equaling 17, what would the likely result of our test be?

Accepted Answer

A)  A P-value larger than 0.05 and we fail to reject the null hypothesis. 
B)  A P-value larger than 0.05 and we reject the null hypothesis. 
C)  A P-value smaller than 0.05 and we fail to reject the null hypothesis. 
D)  A P-value smaller than 0.05 and we reject the null hypothesis.

Question 15

The null distribution is always centered around zero.

Accepted Answer

A) True 
 B)False

Question 16

Which of the following is our best attitude to a test result that returns a nonsignificant result?

Accepted Answer

A)  The null hypothesis is conclusively demonstrated to be correct. 
B)  The null hypothesis is conclusively demonstrated to be incorrect. 
C)  The overall study is inconclusive and the null hypothesis is incorrect. 
D)  The overall study is inconclusive and we shouldn't make a definitive decision.

Question 17

The null hypothesis is a specific claim about the value of a sample statistic.

Accepted Answer

A) True 
 B)False

Question 18

The probabilities of Type I and Type II errors always add up to 1.0.

Accepted Answer

A) True 
 B)False

Question 19

Generally speaking, if we fail to reject the null hypothesis, we should therefore conclude that the null hypothesis is true.

Accepted Answer

A) True 
 B)False

Question 20

When describing the results of a study, we should report three things. What are these three values and why should we include each of them?

Accepted Answer

The answer of When describing the results of a study,...

Exam 6: Hypothesis Testing

The y-axis for a null distribution is probability values.

There is a risk relating to P-values when we look at our data before deciding on a one-sided or two-sided test. Describe this risk with specific reference to the P-value we calculate if we do the wrong test.

When presenting your results in a research paper or report, which of the following is not one of the pieces of information you should always include?

Increasing the value of the significance level tends to do which of the following?

Which of the following statements is correct?

Describe the relationship between a statistical hypothesis and a scientific hypothesis.

The sampling distribution for a test statistic if the null hypothesis is true is called which of the following?

The power of a statistical test is best described as which of the following?

In your own words, describe what a P-value is and how we use it to evaluate statistical hypotheses.

Nonsignificant tests are uninformative.

Describe the major problem with using a nonsignificant result as evidence that the null hypothesis is true.

Which of the following is the best description of what a "two-sided" test means?

Consider a situation in which we calculate a 95% confidence interval that ranges from 18 to 23. If we conducted a two-sided test with the null hypothesis of the population mean equaling 17, what would the likely result of our test be?

The null distribution is always centered around zero.

Which of the following is our best attitude to a test result that returns a nonsignificant result?

The null hypothesis is a specific claim about the value of a sample statistic.

The probabilities of Type I and Type II errors always add up to 1.0.

Generally speaking, if we fail to reject the null hypothesis, we should therefore conclude that the null hypothesis is true.

When describing the results of a study, we should report three things. What are these three values and why should we include each of them?