'''(r)
install.packages('ggplot2')
names(pf)
qplot(x -dob_day, data - pf)
'''
'''(r) qplot(x - friend_count, data - pf) '''
'''(r) qplot(x - friend_count, data - pf, xlim - c(0, 1000)) qplot(x - friend_count, data_pf) + scale_x_continuous(limits - c(0, 1000)) '''
