Which Inference Procedure?

The smaller the p-value, the stronger the evidence against the _____________ hypothesis

• null
• alternative

If the p-value is less than α, we reject H₀

• True
• False

A hypothesis test is performed and
p-value = 0.02. Which is the best conclusion?

• H₀ is rejected at α = 0.01.
• H₀ is rejected at α = 0.05.
• Ha is rejected at α = 0.01.
• Ha is rejected at α = 0.05.

A two-tailed hypothesis test with H₀: μ₁-μ₂ = 0 produced a p-value of 0.08.  Which of the following must be true?

• The 90% confidence interval will NOT contain 0.
• The 95% confidence interval will NOT contain 0.
• The 99% confidence interval will NOT contain 0.
• All the confidence intervals listed will contain 0.

How much faster do people who own sports cars drive on the freeway compared to people who own economy cars.  520 sports cars and 890 economy cars were clocked as they passed by on the freeway. Which procedure is appropriate?

• t interval for means
• t interval for difference of means
• z interval for proportions
• z interval for difference of proportions

How likely are people who see a nickel on the ground to pick it up?  800 people were observed. Which procedure is appropriate?

• z interval for proportions
• z test for proportions
• z interval for difference of proportions
• z test for difference of proportions

An amusement park owner is considering changing her model from "pay for each ride" to "one fee for all rides."  She observes 2000 guests to see if they spend less than the $30 fee that she intends to put into place. Which procedure is appropriate?

• t interval for means
• t test for means
• z interval for proportions
• z test for proportions

How much more time do men spend listening to music compared to women?  52 men and 52 women were surveyed. Which procedure is appropriate?

• t interval for difference of means
• t test for difference of means
• z interval for difference of proportions
• z test for difference of proportions

Are people more likely to die of heart disease or cancer?  20,000 death certificates were examined. Which procedure is appropriate?

• t interval for difference of means
• t test for difference of means
• z interval for difference of proportions
• z test for difference of proportions

Are robin eggs more likely then stellar jay eggs to hatch early during a wet spring?  Eggs of 82 robins and 75 stellar jays were observed this spring. Which procedure is appropriate?

• t test for means
• t test for difference of means
• z test for proportions
• z test for difference of proportions