我有一组数据如下：t是年份，a-j是城市名
需求：现在需要a-j每个变量两两之间之间进行因果推断，需要连续执行quietly jackknife: edm xmap
假如手动操作的话就是quietly jackknife: edm xmap a b; quietly jackknife: edm xmap a c ; quietly jackknife: edm xmap a d...;quietly jackknife: edm xmap a j;


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