Significance Test Proportions Quiz

A large-scale study found that 42% of Americans play video games. A random sample of 1100 teenagers were asked whether they play games online; 575 said they did. Is there sufficient evidence to suggest that the proportion of teens who play video games is different from the national figure? Use a 5% level of significance.

Select the correct hypotheses. (2 answers)

• H0: p = 0.42

• Ha: p = 0.42

• H0: p = 775/1100

• Ha: p ≠ 0.42

• Ha: p ≠ 775/1100

A nationwide survey of 1500 adults asked about attitudes toward “alternative medicine” such as acupuncture, massage therapy, etc. Among the 1500 respondents, 660 said they would use alternative medicine if traditional medicine was not producing the results they wanted. Do these data provide enough evidence to suggest that less than half of all adults would use alternative medicine if traditional medicine didn’t produce their desired results? Use a 5% level of significance.

Select the correct hypotheses. (2 answers)

• H0: p = 0.50

• Ha: p = 0.50

• H0: p = 660/1500

• Ha: p < 660/1500

• Ha: p < 0.50

Sally reads a newspaper report claiming that 12% of all adults in the U.S. are left-handed. She decides to test this claim. Sally selects a random sample of 55 classmates and finds that 9 were left-handed. Does this provide sufficient evidence that the proportion of lefties in Sally’s school is different than the national figure? Use α = 0.01.

Which is the correct conclusion for this test?

• Snice p-value = 0.319 < 0.01, I reject H0. There is enough evidence to suggest a difference.

• Snice p-value = 0.319 > 0.01, I reject H0. There is enough evidence to suggest a difference.

• Snice p-value = 0.319 > 0.01, I fail to reject H0. There is not enough evidence to suggest a difference.

• Snice p-value = 0.319 < 0.01, I fail to reject H0. There is enough evidence to suggest a difference.

When performing a test about the population proportion, what distribution would you need to use? 

• z
• t
• chi-square

In testing hypotheses, which of the following would be strong evidence against the null hypothesis?

• using a small level of significance
• using a large level of significance
• obtaining data with a small p-value
• obtaining data with a low test statistic

Tags

CCSS.HSS.IC.B.5

When p-value is greater than alpha we:

• Reject Ho

• Fail to reject Ha

• Fail to reject Ho

• Reject Ha

• A

• B

• C

• D

A Type I error is when: 

• We reject the null hypothesis when it is actually true
• We obtain the wrong test statistic
• We fail to reject the null hypothesis when it's actually false
• We reject the alternate hypothesis when it's actually true

Failing to reject a null hypothesis that is false can be characterized as

• a Type I error
• a Type II error
• both a Type I and Type II error
• no error

Which of the following is an appropriate interpretation of a p-value?

• The probability of rejecting H₀, when we should have failed to reject H₀.
• The probability of failing to reject H₀, when we should have rejected H₀.
• Assuming H₀ is true, it is the probability of obtaining our sample statistic or a more extreme value.
• Assuming H₀ is NOT true, it is the probability of obtaining our sample statistic or a more extreme value.