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hypothesis testing and one sample Z test question. suppose the latest census dat

ID: 3175837 • Letter: H

Question

hypothesis testing and one sample Z test question.

suppose the latest census data shows that the national average commute time is 25.5 minutes each way with a standard deviation of 2 minutes. You scoff at the news because you think the residents of Pittsburgh have significantly longer commutes than the national average suggests. You survey a random sample of 49 Pittsburghers and find that their average commute time is 26.05 minutes.

the P value for the two-tailed test is p equals .0542. what does this mean?

a. if there is no difference between Pittsburgh residence average commute time and the national average then there is a 5.42 % chance that you would have found no difference.

b. there is a 5.42% chance of drawing the wrong conclusion that Pittsburgh residents average commute time is significantly different from the national average when in fact no difference exists.

c. there is a 5.42% probability that you would have gotten a sample mean of 26.05 minutes.

d. there is a 5.42% probability that the Pittsburgh residents average commute time is the same as the national average.

Explanation / Answer

Here p-value represents type I error.

This means we reject the null hypothesis though it is true.

b. there is a 5.42% chance of drawing the wrong conclusion that Pittsburgh residents average commute time is significantly different from the national average when in fact no difference exists.