Hypothesis Tests

The p- value is

• an alpha level

• significant if it is large

• the test statistic

• a probability

Suppose the P-value for a hypothesis test is 0.0304. Using a = 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

Tags

CCSS.HSS.IC.B.5

When p-value is greater than the given significance level, we:

• Reject Ho

• Fail to reject Ha

• Fail to reject Ho

• Reject Ha

Suppose that the present success rate in treating a certain type of lung cancer is .75. A research group hopes to demonstrate that the success rate of a new treatment of this cancer is better. What are the null and alternative hypotheses?

• H_o : μ = 0.75, H_a : μ < 0.75

• H_o : π > 0.75, H_a : π = 0.25

• H_o : π = 0.75, H_a : π > 0.75

• None of these.

At the Chrysler manufacturing plant, there is a part that is supposed to weigh precisely 19 pounds. The engineers take a sample of parts and want to know if they meet the weight specifications. What are our null and alternative hypotheses?

• H_o : μ = 17, H_a : μ ≠ 19

• H_o : μ = 19, H_a : μ ≠ 19

• H_o : μ = 19, H_a : μ ≠ 17

• H_o : μ = 17, H_a : μ ≠ 17

A random sample of students at a college shows that 54 of 200 students had part-time jobs. We want to see if the proportion of all college students with part time jobs is greater than the national average. Which feature on our calculator would we use to test this?

• T-Test

• 1PropZTest

• TInterval

• 1-PropZInt

Students investigating the packaging of potato chips purchased 6 bags of Lay's Ruffles marked with a net weight of 28.3 grams. They carefully weighed the contents of each bag in order to determine if the bags were underweight. Which feature on our calculator would we use to test this?

• T-Test

• 1-PropZTest

• TInterval

• 1-PropZInt

A Type I error is when: 

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

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?

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

• Since p-value = .0319, I reject H_o. There is not enough evidence to suggest a difference.

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

• Since p-value = .0319 , I fail to reject H₀. There is enough evidence to suggest a difference.

The Quick Stop claims that the Big Slurp will contain 48

ounces of drink. You decide to test this claim because

you feel the actual amount is lower. Over the next few

weeks, you buy 50 Big Slurps and find the average

amount of drink is 47 ounces with a standard deviation

of 2.75 ounces. At α = 0.05, what is your conclusion?

• The p-value is very small, so I will reject H_o. I now believe the average amount of drink in a Big Slurp is less than 47 oz.

• The p-value is large, so I will fail to reject H_o. I will continue to believe that the average amount of drink in a Big Slurp is 50 oz.

• The p-value is small, so I will reject H_o. I now believe that the average amount of drink in a Big Slurp is more than 50 oz.

• No conclusion is warranted, we need a larger sample size.