thomasnwilson
commented
9 years ago It's never easy to find out that your'e the weakest link. I'm glad you and @ARPeters figured it out. What you are saying makes sense. When I have time, I will go back and look at the table and get a better visual. Meanwhile, I will definitely try to work on my positive mojo before we meet again.
@thomasnwilson, we joked about it as you left, but in all seriousness, less than a minute after the door shut behind you, @ARPeters and I figured out the connection between the textbook reference to the Table 9.6-9.8 marginal probability calculations and the CIC formula (so, obviously, you were holding us back:). The mistake I was making during class was overlooking the lack of a subscript on the S(t_[f-1]) term in the incidence calculations, Ic(tf). S(t[f-1]) reflects the survival at the last time period from any and all causes (including the competing risks). Thus in Table 9.6, S(t_[f-1]) at t_f = 5, is actually 1/100 or .01, and that means Ic(t_f = 5) is .01 * 1/1 = .01 as is the cumulative incidence (since CIC(t_f < 5) = 0). This .01 estimate is the the same as the marginal probability estimate demonstrated in Table 9.8. Thought I'd better write this all down before I forget it. We can discuss more next week.