How to get a positive definite spatial weight matrix in Stata

[iris lee]

Hi everyone,

When I use pvarirfcivo package, I met the error :

matrix not positive definite

So I wondering if there is an option to get a positive definite spatial weight matrix in Stata. Looking forward to any advice.

Regards,
Iris

[iris lee]

By using the option eignval(eignv_name) of spwmatrix and

   mat list eignv_name

I found some of eigenvalues are negetive but some not.

Maybe we can't control the weight matrix is or is not positive definite. But it really influence the subsequent calculation for spatial Pvar.