st: Interactions in xtmixed using lincom

[Cody DeHaan <codydh@me.com>]

Hello!

I'm attempting to break down an interaction between two level-1 variables in a two-level model using xtmixed.

I've found examples of this using lincom, but they all seem to be using dichotomous variables instead of continuous.

I have a model:

xtmixed Regret Motivation Outcome Interaction D1 D2 || ID:, cov(un) var

where Regret, Motivation, and Outcome are all continuous, D1 and D2 are two dichotomous dummy variables, and Interaction is Motivation X Outcome.

Would it be correct to analyze the significant Interaction coefficient, looking at the effect of Outcome on Regret at Motivation values of 4, 5, and 6 using lincom commands such as:

lincom Outcome + 4*Interaction
lincom Outcome + 5*Interaction
lincom Outcome + 6*Interaction

Thanks for any help or suggestions you can provide, it's greatly appreciated!
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