Question

A feature of each Facebook user’s profile is the number of “friends”, which indicates the user’s social
network connectedness. Among college students on Facebook, the average number of Facebook
friends has been estimated to be around 250 from a 2008 study. An experiment was run to examine
the relationship between the number of Facebook friends and the user’s perceived social
attractiveness. A group of undergraduates were randomly assigned to observe one of three Facebook
profiles. Everything about the profile was the same except the number of friends, which appeared in
the profile as 102, 502, or 902. After viewing each profile, each participant was asked to fill out a
questionnaire on the social attractiveness of the profile user, with higher scores representing more
social attractiveness. The data are given below.
Group 1 (102 friends): 3.8 3.6 3.2 2.4 4.8 3.0 4.2 3.6 3.2 3.0 4.8 3.4 4.8 6.0
Group 2 (502 friends): 4.6 4.0 4.8 3.0 2.0 5.8 5.6 4.4 4.4 5.6 4.6 5.6 5.6
Group 3 (902 friends): 4.2 4.6 3.0 2.6 5.2 5.2 1.6 5.0 4.4 5.0 3.6 4.2 5.0 3.4
a) Calculate by hand the following statistics for each group separately: Mean, Median, IQR,
Standard deviation
b) Give a brief 23
sentence summary of your findings in terms of comparing the social
attractiveness scores between the three groups.
c) Are there any outliers in any of the groups? Show your work using the IQR.
d) In Minitab, create a comparative boxplot of the social attractiveness score for the three
groups. Print this plot and attach it with your solution. Give a brief 23
sentence summary of
your findings. You will need to enter the data directly into Minitab yourself.
e) If the 6.0 value in group 1 was instead a 10.0, how would this affect each of the measures you
calculated in part a?

Answer 1