st: question on survival analysis and selection correction

[Gáti Annamária <annamaria.gati@tarki-tudok.hu>]

Hello!

I am doing survival analysis on a graduate dataset.
I analyze "how long graduates survive in unemployment" after graduation.
Some find a job in 1 month, some in 3 etc, some not even in 30 month.

There are graduates in my data who do not search for a job after 
graduation as they already had one while doing their studies (they 
mostly did evening courses etc.).

I suppose there is a selection bias I should account for while I am 
doing my survival analysis as those who search for a job after 
graduation are mostly young, doing their studies full time and therefore 
they are definitely different from the ones who earn their degrees while 
working.

Is it possible to use the Heckmann correction methods together with 
survival analysis? That is the only method I have learnt a bit about.
If I need to do this correction what is the way to specify it in my syntax?

annamaria gati
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