Social Networking Sites
In a survey of 2255 randomly selected US adults (age 18 or older), 1787 of them use the Internet regularly. Of the Internet users, 1054 use a social networking site.1 Find a 95% confidence interval for each of the following proportions.
(a) Proportion of US adults who use the Internet regularly.
Round your answers to three decimal places.
The 95% confidence interval is ______ to _______
(b) Proportion of US adult Internet users who use a social networking site.
Round your answers to three decimal places.
The 95% confidence interval is ________ to _______
(c) Proportion of all US adults who use a social networking site.
Round your answers to three decimal places.
The 95% confidence interval is ______ to _____
Use the confidence interval to estimate whether it is plausible to estimate that 50% of all US adults now use a social networking site.
yes or no
1Hampton, K., Goulet, L., Rainie, L., and Purcell, K., ''Social Networking Sites and Our Lives," Pew Research Center, June 16, 2011.