st: A problem with - pstest- command

["Alvaro Zevallos" <azevallos@grade.org.pe>]

Hi all,

I�m testing the quality of matching estimators of five ATT parameters and 
i�m using the - pstest- command after - psmatch2 -, but i stopped because i 
have problems with the results, specifically with the �Standardised Bias� 
Column.

When i replicated the Standardised Bias equation of Rosenbaum and Rubin 
(1985) for all my covariates in Excel the results were the same as 
the -pstest-�s only for unmatched means.

I was trying to find an explanation for the differences between the matched 
means and I found that the -pstest- command uses the square root of the 
average of sample variances before matching as the denominator of the 
�standardised bias� after matching equation. I downloaded  the command again 
but that didn�t solve the problem.
What am I doing wrong?

Thanks a lot!!

Alvaro z. 
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