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Primary and Secondary Occasions using Robust model

PostPosted: Thu Jul 02, 2020 5:17 pm
by statsfordays
Let me start by asking for forgiveness for my ignorance, I am learning RMark on my own and still new to it all.

I am attempting to run a robust model but I am continuously getting an "incorrect structure for time intervals" error. It appears that the secondary occasions are not being accounted for in RMark:

$nocc
[1] 15

$nocc.secondary
NULL

$time.intervals
[1] 1 1 1 1 1 1 1 1 1 1 1 1 1 1

I'm sure this must be a problem on my end with how my data is formatted. Can someone please tell me what painfully obvious detail I am missing?

Re: Primary and Secondary Occasions using Robust model

PostPosted: Thu Jul 02, 2020 6:43 pm
by jlaake
You need to read the chapter on robust designs in Cooch and White and look at ?robust example in RMark. You use 0 for time intervals between secondary occasions and 1 or whatever is appropriate between last secondary of session I and first occasion of session I+1.