Re: st: creating interaction variables

[Richard Williams <Richard.A.Williams.5@ND.edu>]

At 02:45 AM 6/12/2004 +0900, Joseph Coveney wrote:
> Richard is absolutely right and I stand corrected.  The interaction term
> command that allows for continuous-by-continuous interaction terms, in 
> addition
> to those involving categorical-predictor variables, is -xi3- from Michael
> Mitchell and Phil Ender.  It's an extension of -xi- that is downloadable from
> SSC or from the ULCA site.  -help xi3- (after installing the package) will
> showTewodaj the way to the goal.
>
> Joseph Coveney
I stand corrected too because I have -xi3- and didn't realize it could do 
this!  Also, it includes the lower order terms along with the interaction, 
which is good, e.g.

xi3: reg y x1*x2

results in y being regressed on x1, x2, and x1*x2.

-xi3- has a lot of other nice options too.

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