Bookmark and Share

Notice: On April 23, 2014, Statalist moved from an email list to a forum, based at

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

re: st: psmatch2 - exact matching with mahalanobis metric

From   "Ariel Linden, DrPH" <>
To   <>
Subject   re: st: psmatch2 - exact matching with mahalanobis metric
Date   Wed, 3 Oct 2012 10:34:57 -0400

I suggest that you consider using coarsened exact matching, using -cem- (a
user written program found on SSC). If you specify that the specific
variable should have #0 coarsening, it will produce exact matching on that

Date: Tue, 2 Oct 2012 15:17:42 +0200
From: Vincenzo Mariani <>
Subject: st: psmatch2 - exact matching with mahalanobis metric

Dear Users,

I'm trying to implement mahalanobis metric matching using psmatch2,
but I'm not able to exact match on a covariate (say, X). With other
matching algorithms, the propensity score can be appropriately
modified to achieve exact matching, as explained here, for instance:

In my case, I am thinking to solve the problem by performing a
matching iteration for each value of X.  psmatch2 then gives me, for
each obs, the couple (outcome, _outcome), where _outcome is the
outcome of the counterfactual unit.

Then ATT=mean(outcome)-mean(_outcome) for treated. But how do I find
the appropriate (bootstrap) standard errors?

Any help appreciated.

Many thanks,


*   For searches and help try:

© Copyright 1996–2017 StataCorp LLC   |   Terms of use   |   Privacy   |   Contact us   |   Site index