【转】“repeated time values within panel”问题的解决

解决问题。谢谢！

学习笔记1. Do identifier and time uniquely identify the data?Observations in panel data are uniquely identified by the combination of identifier and year.

代码：. isid id time  //检验id和year是否是唯一标识，即是否有重复观测值
结果1：no news is good news
结果2：variables ctnm_id year do not uniquely identify the observations
r(459);
——确实有重复
2. using the duplicates command, which is a small bundle of tools for investigating possible problems arising from duplicated observations.  

. duplicates report ctnm_id year    //查找重复的个数


Duplicates in terms of ctnm_id year


--------------------------------------
   copies | observations       surplus
----------+---------------------------
        1 |          551             0
        2 |            2             1
--------------------------------------
. duplicates list ctnm_id year    //查找重复的观测值


Duplicates in terms of ctnm_id year


  +-----------------------+
  | obs:   ctnm_id   year |
  |-----------------------|
  |  524    610400   2013 |
  |  525    610400   2013 |
  +-----------------------+

太棒了！非常感谢。多亏了这些操作解决了棘手的问题

很棒，刚遇到这个问题

写的太棒了