st: psmatch and matching methods

[Manuel Ch�vez <mchavez@evalalianza.org.mx>]

I'm using psmatch to estimate the matching of several variables and I'm
obtaining very different result on the impact depending if I use the nearest
neighbor, the Mahlanabis distance and the kernel matching methods. My
questions are:

1) If somebody knows why this happen?
2) If it is correct to take the average of the three methods for obtaining a
more acurate estimation of the impacts?


Thanks

Manuel G. Ch�vez Angeles
FAO
Consultor Nacional de Impactos

Providencia No. 334 5� Piso
Col. del Valle
M�xico, D.F. 03100
M�xico
Tel. 11076425/26/30/31 Ext. 319


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