The following data are a realization of an i.i.d. sequence with the common mean value μ
9, 5, 5, 3, 6, 7, 5, 8, 5, 5, 2, 8, 5, 6, 4, 5, 4, 5, 5, 3, 4, 7, 5, 4, 1, 2, 6, 7, 8, 8, 2, 2, 3, 2, 8, 10, 3, 4, 5, 2, 4, 5, 5, 3, 4, 6, 6, 6, 3, 4
(i) Calculate the table of relative frequencies and draw a graph of relative frequencies.
(ii) What is the meaning of a 90% confidence interval for the mean value μ? Find three different approximate 90% confidence intervals for the mean value μ. Which one has the smallest width?