Re: st: Re: Calculating Determinant of Hessian Matrix Over Obervations

[Asgar Khademvatani <akhademv@ucalgary.ca>]

Hello ,

As Michael said, it might be easy directly to calculate the determinant 
of a matrix 2 by 2 by -gen- command, but calculating the determinants of 
matrices with higher degrees such as 3 by 3 and higher might be 
difficult by -gen- command , so the question still remains how can I do 
it through a loop using-det- command?

Asgar

Michael Blasnik wrote:


> listed, then why not just calculate it directly using -gen-?
>
> gen det=A*C-B^2
>
> Michael Blasnik
>
>
> ----- Original Message ----- From: "Asgar Khademvatani" 
> <akhademv@ucalgary.ca>
> To: <statalist@hsphsun2.harvard.edu>
> Sent: Monday, October 01, 2007 7:34 AM
> Subject: st: Calculating Determinant of Hessian Matrix Over Obervations
>
>
>
> > Dear All,
> >
> > I have 43 observation on t he variables  A, B, and C. I am trying to
> > make 43 symmetry Hessian matrix(2 by 2) and calculate each matrix
> > determinant and list the calculated determinants for each observation. I
> > have made the following loop but it is subject to error as follows;
> >
> > forvalues i = 1/43 {
> >    matrix H = (A[`i'], B[`i'] \ B[`i'], C[`i'])
> >   gen det_H =  det(H)
> >    di "`i'"
> >     matrix list Ha_g_1
> >    list det_H
> >    }
> > I am getting the following error as follows;
> >
> >    +----------+
> >     | det_H |
> >     |----------|
> >  1. | 6.28e-13 |
> <snip>
>
> *
> *   For searches and help try:
> *   http://www.stata.com/support/faqs/res/findit.html
> *   http://www.stata.com/support/statalist/faq
> *   http://www.ats.ucla.edu/stat/stata/
*
*   For searches and help try:
*   http://www.stata.com/support/faqs/res/findit.html
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/