1
votes

I'm working on a panel dataset, which has missing values for four variables (at the start, end and in-between of panels). I would like to remove the entire panel which has missing values.

This is the code I have tried to use so far:

bysort BvD_ID YEAR: drop if sum(!missing(REV_LAY,EMP_LAY,FX_ASSET_LAY,MATCOST_LAY))==0

This piece of code successfully removes all observations with missing values in any of the four variables but it retains observations with non-missing values.

Example data:

  Firm_ID  Year  REV_LAY  EMP_LAY  FX_ASSET_LAY
  001      2001  80       25       120
  001      2002  75       .        122
  001      2003  82       32       128
  002      2001  40       15       45
  002      2002  42       18       48
  002      2003  45       20       50

In the above sample data, I want to drop panel Firm_ID = 001 completely.

1

1 Answers

2
votes

You can do something like:

clear
input Firm_ID  Year  REV_LAY  EMP_LAY  FX_ASSET_LAY
  001      2001  80       25       120
  001      2002  75       .        122
  001      2003  82       32       128
  002      2001  40       15       45
  002      2002  42       18       48
  002      2003  45       20       50
end

generate index = _n
bysort Firm_ID (index): generate todrop = sum(missing(REV_LAY, EMP_LAY, FX_ASSET_LAY))
by Firm_ID: drop if todrop[_N]

list Firm_ID Year REV_LAY EMP_LAY FX_ASSET_LAY

   +-----------------------------------------------+
   | Firm_ID   Year   REV_LAY   EMP_LAY   FX_ASS~Y |
   |-----------------------------------------------|
1. |       2   2001        40        15         45 |
2. |       2   2002        42        18         48 |
3. |       2   2003        45        20         50 |
   +-----------------------------------------------+