Free Practice Quiz Question List

08 Hypothesis Testing Online Quiz Questions

Use this free practice quiz with 20 questions to review 08 Hypothesis Testing, test your knowledge, and prepare for your next test or exam.

20 questions

True or false

1 point

True or false: The significance level $\alpha$ is the maximum probability of rejecting $H_0$ when $H_0$ is actually true.

A
True
B
False

Choose one

1 point

A study seeks evidence that a population mean is greater than a specified reference value. Which alternative hypothesis and test direction are appropriate?

A
$H_a:\mu=\mu_0$ , no-tailed test
B
$H_a:\mu<\mu_0$ , left-tailed test
C
$H_a:\mu>\mu_0$ , right-tailed test
D
$H_a:\mu\ne\mu_0$ , two-tailed test

Choose all

1 point

Which two statements correctly describe a p-value? Select all that apply.

A
It is computed under the assumption that $H_0$ is true.
B
It is the probability that $H_0$ is true.
C
It considers outcomes at least as extreme as the observed statistic in the specified direction.
D
It directly measures the practical importance of the observed effect.

Fill in the blank

1 point

Using the p-value approach with $p=0.032$ and $\alpha=0.05$ , the decision is to .

True or false

1 point

True or false: If a hypothesis test fails to reject $H_0$ , the result proves that $H_0$ is true.

A
True
B
False

Choose one

1 point

Which test statistic is generally appropriate for testing a population mean when the population standard deviation is unknown and the sample standard deviation is used?

A
$z=\frac{\bar{x}-\mu_0}{\sigma/\sqrt{n}}$
B
$t=\frac{\bar{x}-\mu_0}{s/\sqrt{n}}$
C
$t=\frac{\bar{x}-\mu_0}{\sigma\sqrt{n}}$
D
$z=\frac{\bar{x}-\mu_0}{s\sqrt{n}}$

Choose all

1 point

Which changes generally increase the statistical power of a hypothesis test? Select all that apply.

A
Increasing the sample size.
B
Increasing the true effect size.
C
Lowering the significance level while holding other factors fixed.
D
Reducing measurement variability.

Fill in the blank

1 point

Statistical power is given by $\text{Power}=$ , where $\beta$ is the Type II error probability.

Written response

1 point

A battery-life claim has $\mu_0=10$ hours, $n=64$ , $\bar{x}=10.4$ hours, and known $\sigma=1.6$ hours. What is the z statistic?

Open ended

1 point

A company claims that its batteries last an average of 10 hours. An independent sample has $n=64$ , $\bar{x}=10.4$ hours, known $\sigma=1.6$ hours, and a right-tailed test with $p\approx0.023$ at $\alpha=0.05$ . Write a complete, context-based conclusion, including what the result does not establish.

True or false

1 point

True or false: A statistically significant result necessarily represents a practically important effect.

A
True
B
False

Choose one

1 point

For a two-tailed standard normal test with $\alpha=0.05$ , which critical-value rule is appropriate?

A
Reject when $z\ge1.645$ .
B
Reject when $z\le-1.645$ .
C
Reject when $|z|\ge1.96$ .
D
Reject when $|z|\le1.96$ .

Choose one

1 point

Which statement best describes the null hypothesis in a hypothesis test?

A
The alternative hypothesis, because it describes the effect being investigated.
B
The null hypothesis, because it is the default claim and includes equality.
C
The test statistic, because it summarizes the sample result.
D
The p-value, because it measures evidence against a claim.

Choose one

1 point

A researcher would regard both an increase and a decrease from the claimed population mean as important. Which alternative-hypothesis form is most appropriate?

A
Use a right-tailed alternative because every test should focus on increases.
B
Use a left-tailed alternative because decreases are generally easier to detect.
C
Use a two-tailed alternative because departures in either direction matter.
D
Use no alternative hypothesis until after examining the sample results.

Choose one

1 point

What does a significance level of $\alpha=0.05$ represent?

A
The maximum probability of rejecting a true null hypothesis.
B
The probability that the null hypothesis is true.
C
The probability that the final conclusion is correct.
D
The probability that the alternative hypothesis is false.

Choose one

1 point

Which expression best represents the general structure of a test statistic?

A
The null value divided by the sample size.
B
The standard error divided by the observed estimate.
C
The sample mean multiplied by the population parameter.
D
The observed estimate minus the null value, divided by the standard error.

Choose one

1 point

A test uses the alternative $H_a:\mu>\mu_0$ . Which area represents its p-value?

A
The area to the left of the observed statistic.
B
The area to the right of the observed statistic.
C
The area in both tails, regardless of the alternative hypothesis.
D
The probability that the null hypothesis is true.

Written response

1 point

What is the standard name for rejecting $H_0$ when $H_0$ is actually true?

Written response

1 point

What is the standard term for the probability of rejecting $H_0$ when the alternative is true?

Written response

1 point

A quality-control test fails to reject the claim that a machine is correctly calibrated, even though the machine is actually miscalibrated. What is the name of this error?