Generating variable based on two groups

[Javier Vasquez]

Hello,

I'm working with a dataset from Comtrade, which include information about import, export and their respective trade values for 3 different countries: Italy, Belgium and Israel.
The data looks like this:

tradeflow | reporter | partner | tradevalues

import | belgium | israel | 1891976735
export | belgium | israel | 2663650495
import | belgium | italy | 14696719360
export | belgium | italy | 21122317754
import | italy | belgium | 20047180815
export | italy | belgium | 15239360972
import | italy | israel | 927106045
export | italy | israel | 2942813832


Based on this, I'd like to generate a variable which shows the sum of import and export tradevalues by each combination of countries. For example, a variable which shows the sum of tradevalues for Belgium and Israel in the first two rows (say, 1891976735+2663650495) . Then, another sum for Belgium and Italy in the row 3 and row 4 (14696719360+21122317754).

Again, the idea is to generate a variable which shows import+export for each combination of reporter and partner.

Thanks!

[Carlo Lazzaro]

Javier:
you may want to try something along the following lines:

. egen flag=group( reporter partner)

. bysort flag: egen overall=total( tradevalues)

[Marcos Almeida]

If I understood right, you may as well type:

by reporter partner, sort: egen mytot = total(tradevalues)

[Nick Cox]

If #2 or #3 is what you want, fine. But be aware of the extra trickery discussed at https://www.stata-journal.com/articl...article=dm0043

dm0043 is thus an otherwise unpredictable search term for mentions here on Statalist.

[Javier Vasquez]

Both Carlo's code and Marcos' Code worked!
Thanks a lot
Best,