Hi,
I am working with some variables that or "wrong" in the sense that if one
share was taken off the market (i.e. the company was dissolved), the last
value of the variable is repeated instead of containing missing values.
e.g.
Status Year Var1
Listed 1991 0.9
Listed 1992 0.95
Listed 1993 0.93
Delisted 1994 0.93
Delisted 1995 0.93
..
Delisted 2006 0.93 (value is always repeated up to present time)
Whereas years 1994-2006 should contain missing values. I came up with this
cleaning process:
foreach X of varlist var1 var2 var3 {
generate `X'new=`X'
replace `X'new=. if `X'==L.`X'
replace `X'=`X'new
drop `X'new
}
Which is okay, but also sets the value to missing if one observation for a
listed company repeats, so it also deletes observations that would be fine.
Any suggestions on how I can only replace the "wrong" values?
Thanks in Advance. Tom
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