By "pull out", do you mean "drop" or "keep"? Here's a way
to keep them. Let -id- identify individuals, -time-
identify periods, and -status- be dichtomous variable of
interest.
/* tag those who transition from period to period */
bys id (time) : gen transition=(status!=status[_n-1])|(_n==1)
/* check if individual always transitions */
bys id : egen alwaystransits=min(transition)
/* if they always transitioned, notrans==0 */
keep if alwaystransits
This keeps those who transition between every time period.
hth,
Jeph
Dmitriy Krichevskiy wrote:
Dear Statalisters,
I have a panel data set with about 14000 people and 21 time periods. I
wanted to pull out persons who have transitioned from one category of
the same dichotomous variable to another (say from lowest income
quintile to the highest) during one time increment - for the whole
duration on the sample. So, essentially, I need to pull out all the
people that did that transition from first period to second plus from
second to third and so on... I know it is a simple loop but whatever I
do Stata drops all of the observations. Perhaps, I should also mention
that I am new to programing altogether. Thanks for all of your help,
Statalisters definitely will be thanked in my dissertation.
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