如何使用 SAS 从 table 中获取高发生变量？

Question

我有一个table如下

level1      level2
furniture   chair
furniture   chair
furniture   table
food        pizza

我想获得唯一的 1 级变量和该变量出现次数最多的 2 级变量。输出：

level1      level2
furniture   chair
food        pizza

Answer 1

1. 汇总数据以获得计数，PROC FREQ。

2. 按 level1 降序排序。

3. 使用数据步和 BY 组处理获取每个级别的第一个观测值1。

   proc freq data=have order = freq;
   table level1*level2 / out=counts;
   run;
   
   proc sort data=counts;
   by level1 descending Count;
   run;
   
   data want;
   set counts;
   by level1;
   if first.level1;
   run;