每周时间滞后

Question

假设有以下数据集：

data dataset;
  input week_number Var1 Var2;
cards;
1  55  98
2  34  34
3  21  0
4  76  12
5  98  0
.. ... ..
52 21  43
;run;

计算和添加以下内容的最佳方法是什么：滞后-1周；滞后+1周；滞后-2周；比原始数据集滞后+2周？

提前谢谢您

Answer 1

使用

proc sql

，您可以多次连接数据本身，并使用连接条件控制每行中出现的周：

proc sql;
    create table want as
    select have.*
            ,lag1.Var1 as Var1_lag1
            ,lag1.Var2 as Var2_lag1
            ,lag2.Var1 as Var1_lag2
            ,lag2.Var2 as Var2_lag2
            ,lead1.Var1 as Var1_lead1
            ,lead1.Var2 as Var2_lead1
            ,lead2.Var1 as Var1_lead2
            ,lead2.Var2 as Var2_lead2
    from dataset have left join dataset lag1 on lag1.Week_number = have.week_number - 1
                    left join dataset lag2 on lag2.week_number = have.week_number - 2
                    left join dataset lead1 on lead1.week_number = have.week_number + 1
                    left join dataset lead2 on lead2.week_number = have.week_number + 2
    ;
quit;

带有

_lag1

的变量具有延迟 1 周、

_lag2

延迟 2 周、

_lead1

提前 1 周和

_lead2

提前 2 周的值。