Selecting observations from specific waves in a panel.

[Jean Jacques]

Hi guys! I have a panal with the variable wave and pid (identifier). Lets assume wave goes from 1 to 8. How can I get those observations that appear lets say in waves 2,5 and 6. Note there's not need to observe the individuals only in those waves: the individual can be also observed in wave 1 but I want to be sure it appears in wave 2,5 and 6.

Cheers and thanks!

[Nick Cox]

egen wanted = total(inlist(wave, 2, 5, 6)), by(pid) 

keep if wanted == 3

[Jean Jacques]

Thanks Nick! It worked perfectly!