As I understand it, each -tvol- is repeated for each
-id year- combination, but you want to use its value
just once. That's a little tricky, but it looks all
downhill from there.
egen tag = tag(id year)
egen tsum = total(tag * tvol), by(year)
gen tshare1 = tvol / tsum
gen tshare2 = tvol / (tsum - tvol)
Nick
[email protected]
Roy,Suryadipta
I am actually trying to generate the last three
columns (tsum, tshare1, tshare2). Their formulae are given
below the data:
id year oid did dist tvol tsum tshare1 tshare2
1 2000 1 2 5 1 6 0.17 0.2
1 2000 1 3 10 1 6 0.17 0.2
1 2000 1 4 15 1 6 0.17 0.2
1 2001 1 2 5 2 4 0.5 1
1 2001 1 3 10 2 4 0.5 1
1 2001 1 4 15 2 4 0.5 1
1 2002 1 2 5 3 17 0.18 0.21
1 2002 1 3 10 3 17 0.18 0.21
1 2002 1 4 15 3 17 0.18 0.21
2 2001 2 1 5 2 4 0.5 1
2 2001 2 3 4 2 4 0.5 1
2 2001 2 4 2 2 4 0.5 1
2 2002 2 1 5 4 17 0.24 0.31
2 2002 2 3 4 4 17 0.24 0.31
2 2002 2 4 2 4 17 0.24 0.31
4 2000 4 1 15 5 6 0.83 5
4 2000 4 2 2 5 6 0.83 5
4 2000 4 3 5 5 6 0.83 5
4 2001 4 1 15 4
4 2001 4 2 2 4
4 2001 4 3 5 4
4 2002 4 1 15 10 17 0.59 1.43
4 2002 4 2 2 10 17 0.59 1.43
4 2002 4 3 5 10 17 0.59 1.43
tsum= sum of tvol for all id-s on any particular year;
tshare1= tvol/tsum;
tshare2=tvol/(tsum-tvol).
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