st: How do I calculate prvalues for specific time points in my survival analysis?

[Laura Templeton <ltempleton@ualberta.ca>]

Hello,

I am using discrete-time survival analysis to inspect the effects of a 
host of background variables on employment state. I have 4 years of data 
which has been broken down into person/month units. Event completion is 
determined at each month with those finding appropriate employment 
dropping from further analysis (using stset command).  Depending on when 
a person is dropped from analysis (i.e., event completion=suitable 
employment), I can have up to 48 time points per person.

My question:

I would like to be able to talk about the predicted probability of white 
men, white women, non-white men and non-white women finding suitable 
employment at specific time points (end of year 1, end of year 2, etc) 
and am having trouble with the code.

So far I am successfully able to report the predicted probability of 
finding appropriate employment for each additional month in the labour 
market with this code:

FOR WHITE MEN
prvalue, x(female 0 vismin 0) rest(mean)

FOR WHITE WOMEN
prvalue, x(female 1 vismin 0) rest(mean)

However, what I really want to know is: what is the predicted 
probability of being appropriately employed by the end of the first year 
(months==12) or by the end of the 2nd year (months==24) for white men? 
Or white women? etc…

Any tips on how I would incorporate the time element into my syntax is 
most appreciated!

Laura
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