GlobalWebIndex reports that American Internet users spend an average of 1.72 hours per day on social media platforms (SocialTimes website, December 4, 2015). Suppose we collect a sample of 75 teenage American Internet users. The data are in the DATAfile named Social-Media. These data provide the number of hours respondents spend on a recent day on social media platforms.
a. Use the SocialMedia data set to develop a point estimate of the number of hours that teenage American Internet users spend per day on social media platforms. Compare this to the actual number of hours American Internet users spend per day on social media platforms. Are you surprised?
b. What is the sample standard deviation?
c. Develop a 95% confidence interval for the number of hours that teenage American Internet users spend per day on social media platforms.