Description

Harris Interactive® conducted a poll of American adults in August of 2011 to study the use of online medical information. Of the 1,019 randomly chosen adults, 60% had used the Internet within the past month to obtain medical information. For 1 – 4, using the formula, show your steps leading you to your confidence interval.

Use the results of this survey to create an approximate 95% confidence interval estimate for the percentage of all American adults who have used the Internet to obtain medical information in the past month.

Calculate the 90% confidence interval.

Which confidence interval has the smaller margin of error? Why does this make sense?

Which confidence interval is more likely to contain the true percentage of all American adults who have used the Internet to obtain medical information in the past month? Why do you think so?

Next, you’ll be using StatCrunch to confirm your answer from above. Before, you use StatCrunch, you need to find “how many adults out of the 1,019 randomly chosen adults used the internet within the past month to obtain medical information”

Click on the Stat drop-down menu and select Proportion Stats → One Sample → With Summary

Enter the # of success ( this is how many adults out of the 1,019 used the internet within the past month to obtain medical information)

Enter the # of observations ( this is your sample size)

Select “Confidence interval for p”

The Level can be 0.90, 0.95, or 0.99 depending on the confidence interval you want.

Click on COMPUTE! to get your results

Copy and paste your results into your response ( CTRL a selects your table and CTRL c copies your table, once you’re back on canvas you can do CTRL v to paste your table)