st: 3-way interactions & xi3

["Danielle H. Ferry" <dferry@nber.org>]

Hi,

I am trying to use <xi3> to run a regression w/ a 3-way interaction. 
This works fine unless as long as I have con*con*con. As soon as 
introduce a categorical variable into the interaction, however, I get 
the error "varlist not allowed". An example of a reg where I run into 
this problem is:

xi3: reg brthLn i.state*i.ageCat*popnLn

Any help would be greatly appreciated. Thanks.

Danielle Ferry
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