Hi!
I have a longitudinal linear mixed model with the term:
and some other covariates. Cov1 is a time-varying covariate.
I also run the model a second time with the within component of cov1 in the interaction term, instead of the between component. What I would like to ask, is in what way I should use margins to understand the results of these interactions. I have thought that, in order to interpret the between-term (each persons average level of cov1), I should use:
This will show how persons with a cov1_between of a certain level change values of dependent variable with age.
However, for the within-term, the question is whether a change in cov1 level is associated with a corresponding change in the dependent variable. To understand this, should I use:
Any advice is greatly appreciated!
Best,
Kjell Weyde
I have a longitudinal linear mixed model with the term:
Code:
c.age##c.age##c.age##c.cov1_between
I also run the model a second time with the within component of cov1 in the interaction term, instead of the between component. What I would like to ask, is in what way I should use margins to understand the results of these interactions. I have thought that, in order to interpret the between-term (each persons average level of cov1), I should use:
Code:
margins, at(age=(0 (12) 96) cov1_between=(30 45 60)), atmeans
However, for the within-term, the question is whether a change in cov1 level is associated with a corresponding change in the dependent variable. To understand this, should I use:
Code:
margins, dydx(cov1_within) at(age=0 (12) 96), atmeans
Best,
Kjell Weyde