AP Statistics Intro to Hypothesis Testing

Identify the correct null hypothesis:

Is the proportion of babies born male different from 50%? In a sample of 200 babies, 96 were male. Test the claim using a level of significance of 1%.

• H₀: p = 0.50

• H₀: µ = 100

• H₀: p = 0.48

• H₀: µ = 96

Conduct a test to determine whether or not the population proportion of voters in favor of proposal A is greater than 50%. In a random sample of 200 voters, 140 said that they were in favor of this proposal. Compute the test statistic.

• z = 7.708

• z = 5.66

• p = 7.7 x 10^-9

• None of the above

Which of the following shows a right-tailed test?

• Ha: µ < 15

• H₀: µ < 15

• Ha: µ > 15

• H₀: µ > 15

Suppose the P-value for a hypothesis test is 0.0304. Using a = 0.05, what is the appropriate conclusion?

• Reject the null hypothesis

• Reject the alternative hypothesis

• Fail to reject the null hypothesis

• Fail to reject the alternative hypothesis

A company that ships glass for a glass manufacturer claimed that its shipping boxes are constructed so that no more than 8 percent of the boxes arrive with broken glass. The glass manufacturer believed the actual percent is greater than 8 percent. The manufacturer selected a random sample of boxes and recorded the proportion of boxes that arrived with broken glass. The manufacturer tested the hypotheses H_o:p=0.08 versus H_a:p>0.08 at the significance level of α=0.01 . The test yielded a p-value of 0.001. Assuming all conditions for inference were met, which of the following is the correct conclusion?

• The p-value is greater than α, and the null hypothesis is rejected. There is convincing evidence that the proportion of all boxes that contain broken glass is greater than 0.08.

• The p-value is greater than α, and the null hypothesis is rejected. There is not convincing evidence that the proportion of all boxes that contain broken glass is greater than 0.08.

• The p-value is greater than α, and the null hypothesis is not rejected. There is not convincing evidence that the proportion of all boxes that contain broken glass is greater than 0.08.

• The p-value is less than α, and the null hypothesis is rejected. There is convincing evidence that the proportion of all boxes that contain broken glass is greater than 0.08.

• The p-value is less than α, and the null hypothesis is not rejected. There is not convincing evidence that the proportion of all boxes that contain broken glass is greater than 0.08.

Answer explanation

The null hypothesis is rejected because the p-value (0.001) is less than α=0.01. There is convincing evidence to support the alternative hypothesis that the population proportion is greater than 0.08.

• B
• C
• D
• E

• a) Reject Ho

• b) Reject Ha

• c) Fail to reject Ho

• d) Fail to reject Ha

When performing a significance test, we're looking for convincing evidence to __________ the null hypothesis in favor of the alternative hypothesis.

• refute

• dispute

• reject

• accept

It is a statistical method applied in making decisions using experimental data. Hypothesis testing is basically testing an assumption that we make about a population.

• conclusion

• hypothesis testing

• hypothesis

• proposition

A random sample of 60 Grade 9 students were subjected to a new teaching strategy. The sampled students made an average of 84 in a quiz. Can it be concluded that the score of the respondents is different from the score of the primary study which is 82 with a deviation of 8? Identify the null hypothesis.