Suppose the marketing research firm comScore would like to examine if the social networking site that a person primarily uses is influenced by his or her age. In a randomly drawn sample, 355 social network users were asked which site they primarily visited. These data are presented in the following table along with each person’s age group:

Age Group Facebook Twitter LinkedIn 2–17 25 14 3 18–34 100 30 11 35–54 98 18 19 55 and older 27 3 7

a. Using a = 0.05, perform a chi-square test to determine if the age group of a social network user and the site he or she primarily visits are independent.

b. What conclusions can be made based on these results?

c. Determine the p-value using Excel and interpret its meaning.

d. Verify your results using PHStat.

AppendixLO1