求助一道题目！给点思路都行！眼下要交了，一点头绪都没有。
1.    Copy the dataset “Prdsal3” from Sashelp into your working library.
2.    Compare actual monthly sale value in 1997 in the following:
•    Output mean sales value of each “country/state/product type/product” combination in each month into a new data set (Hint: use PROC MEANS).
•    Use ANOVA and Kruskal Wallis test to compare if the means are different over the twelve months. Include plot to check assumptions.
•    Change the data structure so that mean sales value of each combination forms a long format, i.e. create twelve variables denoting twelve-month sales value from January to December.
•    Use one-way repeated measurement ANOVA and Friedman test to compare if the mean sales value is different over the twelve months.
•    Do the four comparisons agree with each other?

[此贴子已经被作者于2009-3-27 11:53:50编辑过]