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

 From Asgar Khademvatani <[email protected]> To [email protected] Subject Re: st: Re: Calculating Determinant of Hessian Matrix Over Obervations Date Mon, 01 Oct 2007 12:48:40 -0600

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" <[email protected]>
To: <[email protected]>
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 |
```
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