Hypothesis Testing - Proportions and Means

Which of the following represents the appropriate null & alternative hypotheses?

The mean height of women is greater than 64"

• H₀: μ > 64"

  Hₐ: μ ≠ 64"

• H₀: μ < 64"

  Hₐ: μ > 64"

• H₀: p > 64"

  Hₐ: p ≠ 64"

• H₀: p ≠ 64"

  Hₐ: p > 64"

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

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

• z
• t
• chi-square
• it depends on n

Which of the following shows a right-tailed test?

• H_a: µ ≠ 15

• H_a: µ < 15

• H_a: µ > 15

• H₀: µ ≥ 15

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 large P-value

A P-value indicates:

• the probability that the null hypothesis is true
• the probability that the alternative hypothesis is true
• the probability of obtaining the results (or one more extreme) if the null hypothesis is true
• probability of a Type I error

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

• a) Reject the null hypothesis

• b) Reject the alternative hypothesis

• c) Fail to reject the null hypothesis

• d) Fail to reject the alternative hypothesis

When P-value is greater than alpha we:

• Reject H_o

• Fail to reject H_a

• Fail to reject H_o

• Reject H_a

A mayor is concerned about the percentage of city residents who express disapproval of his job performance. His political committee pays for a newspaper ad, hoping to keep his disapproval rating below 21%. They will use a follow up poll to access effectiveness. What are the correct null and alternative hypotheses?

• Ho: μ > 21

  Ha: μ < 21

• Ho: p > .20

  Ha: p < .20

• Ho: p < .21

  Ha: p > .21

• Ho: p > .21

  Ha: p < .21

On average, 86% of all enrolled college students are undergraduates. A random sample of 500 college students revealed that 420 were undergraduates. At α = 0.10 level, is there enough evidence to conclude that the proportion is lower than the national average?

Choose the correct hypotheses.

• H₀: p ≥ 0.86

  H_a: p < 0.86

• H₀: p ≤ 0.86

  H_a: p > 0.86

• H₀: p = 0.86

  H_a: p ≠ 0.86

• H₀: p < 0.86

  H_a: p ≥ 0.86