duration of employment spells by personal id

[karin kristensson]

Hi!

I would like to calculate duration of low wage employment (dummy 0/1) for each individual in my data set.
My data is in long format, every personal identifier is repeated ten times, one for each year. Do any of you have any ideas of how to create a new variable that captures the duration of the spell/ if low wage emplyment lasts for all years in the data set/only a couple of years etc, by personal id? That is for the specific individual.

best,
Karin

[Øyvind Snilsberg]

maybe this is what you want,

bys id (year): gen spell = sum(dummy!=dummy[_n-1])
bys id spell (year): gen duration = year[_N]-year[1]

[karin kristensson]

Thank you! that worked

[karin kristensson]

maybe this is what you want,

bys id (year): gen spell = sum(dummy!=dummy[_n-1])
bys id spell (year): gen duration = year[_N]-year[1]

Or actually there is a problem with using this, maybe you can help me to figure out how to alter the code. It calculates the duration of any spell, 1, 0 or missing. Even when I recode the dummy to two different dummies, only containing 1 (for low wage or high wage) and the rest missing, it still calculates the missings as, thus I cannot seperate spells from each other I cannot seperate if it is a low wage or a high wage spell. I need something like bys id (year): gen spell = sum(dummy if dummy=1 !=dummy[_n-1]).

Best,
Karin

[karin kristensson]

Or I just sorted it with replacing the duration with . if the dummy is . maybe not the finest coding but it got me the information I wanted, thanks again!