Re: st: Matrix manipulation.

[Thomas Gschwend <gschwend@uni-mannheim.de>]

Going back to the original question Victor asked, and I am not sure what 
he is planning to do or whether I understand him correctly, but if you 
try to calculate predicted values and uncertainty estimates for certain 
scenarios that involve interaction terms you can use -clarify- (findit 
clarify)  without doing the matrix manipulations yourself.

Best,
Thomas



> --- Victor Mauricio Herrera <vherrera@wisc.edu> wrote:
>   
> > > > I'm running a regression model and then using the matrix of
> > > > coefficients e(b) for additional calculations. In the model I
> > > > have an interaction term between two dichotomous variables (i.e.
> > > > gender-by-obesity, with women coded as 0 and men coded as 1).
> > > > The coefficient for obesity in women is already in e(b) but not
> > > > the coefficient for obesity in men. I know I can easily
> > > > calculate this coefficient using lincom, but the problem is that
> > > > I need to add the coefficient for obesity in men as an additional
> > > > column to the e(b) matrix, to be able to do additional
> > > > calculations using e(b). In not very familiar with matrix
> > > > manipulation and I wonder if there is an easy way to do this. 
> > > >         
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