Question

Age and September 11 Refer to Exercise 42. The study also reported that $86\%$ of

millennials included $9/11$ in their top-10 list and $70\%$ of baby boomers included $9/11$.

a. Explain why you do not have enough information to give confidence intervals for

millennials and baby boomers separately.

b. Do you think a $95\%$confidence interval for baby boomers would have a larger or smaller margin of error than the estimate from Exercise 42? Explain your answer.

Short answer

a. It is because sample size is not given.

b. Margin of error is large.

Step-by-step solution

Ste 1: Given Information

It is given that $85\%$of millennials includes $9/11$in their top 10 and$70\%$for baby boomers included$9/11$

Why we do not have enough information to give confidence intervals formillennials and baby boomers separately

To calculate confidence interval, we require sample size, sample proportion and confidence level. We are not given sample size, so it is not possible to find confidence interval.

To check if margin of error is less or large as per given conditions

If sample size decrease, baby boomers in sample is less than total individuals in sample. Hence we will get less information about population, less accurate estimates are obtained. We get less chances of true population proportion containing confidence interval. So, confidence interval is wider. Margin of error is half the width of confidence interval, there will be larger margin of error.