st: Spatial regression with non-symmetric weights

[<V.Monastiriotis@lse.ac.uk>]

Dear Statalist,
I am trying to run a spatial lag model (and spatial dependence tests in
the base OLS regression) using a non-symmetric weights matrix (based on
commuting flows). However, --spatwmat-- refuses to load the matrix
because it is non-symmetric. I have tried to resolve this by deriving
the eigenvalues of my weights matrix separately (using --geneigen-- on
the basis of the discussion in
http://www.stata.com/statalist/archive/2006-03/msg01020.html), but Stata
freezes when I run the command (I have a dataset of 376 observations, so
the full matrix has 141376 cells). Further, I don't know if the
eigenvalues derived from geneigen are suitable for use with spatreg,
spatgsa, etc. 

Can anybody help?
-	Is there some other package or set of commands that allows
spatial analysis in Stata for non-symmetric weights matrices? (I have
looked at the --spwmatrix-- command, which presumably works with
non-symmetric matrices, but I haven't figured out how to use my
commuting data in the context of this command...)
-	Is the --geneigen-- route a valid way to overcome this? 
-	If so, any ideas as to what I should be looking at in order to
make --geneigen-- run on my PC?

Many thanks in advance!
Vassilis

===============================================
Dr Vassilis Monastiriotis
Hellenic Observatory, European Institute, LSE 
email: v.monastiriotis@lse.ac.uk 
===============================================

 

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