Carmen Homework 12 - CI and HT for Means

The value of α will change if you get a new data set.

False

When you are asked to provide a range of likely values for the average gas price in Columbus Ohio, what technique do you use?

Confidence interval for the population mean.

Suppose someone claims the average delivery time for U.S. packages to be delivered during December is 2 days. You believe it takes longer than that. You conduct a hypothesis test; what are your hypotheses?

Ho: µ = 2 vs. Ha: µ >2

Suppose you found a 95% confidence interval for the mean using a random sample of size n, and you found it was too wide; that is, the margin of error was too large. If you wanted the margin of error to be ¼ of what it was before, what do you have to do to the sample size?

Increase it by 16 times what it was before

Which of the following would increase the Margin of Error?

Increase the Confidence

If everything else stays the same, a 90% confidence interval is narrower than a 95% confidence interval.

True

The margin of error of a confidence interval increases if the population has a higher standard deviation.

True

The p-value will change if you get a new data set.

True

If your 95% confidence interval for the average gas price in Columbus Ohio turned out to be ($2.25, $2.75), do you know what the sample mean was?

Yes

Your friend claims the average price of a burger in the Columbus Gateway Area is $10.00. You believe it's lower than that. What symbol represents the $10 in this scenario?

µ0