i have a 7400 case dataset representing a workforce with a current tenure (in years) as well as other attributes assigned to each case. i would like to model how the composition of that workforce changes after a certain date (between old employees and new employees) over the next six years based on an imputed probability of separation/survival constant (S) based on full/part time designation.

my basic strategy is to have SPSS creat a set of seven variables (t) for each year of the six years i'm looking out into the future (y), with the probability (p) that someone occuping position (yt) is new - essentially the equation p_y_t =p_[y-1]_[t-1]*S where p_y[1...6]_t[1] = 1-S

i am trying to tell SPSS to do that for me using the LOOP-END LOOP command but am not having too much luch since i've actually never used this command successfuly. the syntax guide isn't doing me much good.

any suggestions?