Question

21. Bob’s local pizza place claims it delivers pizzas in 30 minutes on average. Bob is convinced it’s more than that. He does a hypothesis test and gets a p-value of .001.

a. What does Bob conclude?

b. If Bob made the wrong conclusion what error did he make?

c. What would be the impact of his error?

22. Bob’s local pizza place claims it delivers pizzas in 30 minutes on average. Bob is convinced it’s more than that. He does a hypothesis test and gets a p-value of .10.

a. What does Bob conclude?

b. If Bob made the wrong conclusion what error did he make?

c. What would be the impact of his error?

23. Which type of error is the same as the significance level of a hypothesis test?

a. Type 1 error

b. Type 2 error

c. Both

d. Neither

Answer 1

21. p -value = 0.001

a) As p-value < 0.05, we conclude that the null hypothesis is reject.

There is enough evidence to reject the claim that Bob’s local pizza place delivers pizzas in 30 minutes.

b) If he made the wrong conclusion then he made a Type I error.

Type I error is rejecting the null hypothesis when it is true.

c) The impact of this error will be that he concluded that the pizza delivery take time more than 30 minutes, while in reality it was a 30 minutes or less on average.

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22. p -value = 0.10

a) As p-value > 0.05, we fail to reject the null hypothesis.

There is not enough evidence to reject the claim that Bob’s local pizza place delivers pizzas in 30 minutes.

b) If he made the wrong conclusion then he made a Type II error.

Type II error is failing to reject the null hypothesis when it is not true.

c) The impact of this error will be that he concluded that the pizza delivery take 30 minutes, while in reality it was is more than 30 minutes.

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23. Answer : a. Type I error.