st: ATE with binary outcome

[Ronnie Babigumira <rb.glists@gmail.com>]

Dear Listers

(Setup: Stata 9.2, WinXP, -pscore- version 2.02)

I'm a novice at the matching game so I beg your indulgence if I ask the obvious.

I am trying to use propensity score matching to estimate the average treatment effect (ATE). However, my outcome is 
binary (0,1).

My plan was to use -pscore- [SJ-2-4, Becker & Ichino] and following the example in the article,

a. run -pscore- to estimate the propensity score
b. run one of the att* programs to estimate the ATE

Here are my questions

1. Like most of the other work I have seen, the example deals with a continuous outcome. Can I extend this to binary 
outcome (if yes, would anyone have an example of publication that has gone down this road)?

2. If it is OK (I just tried it out with my data), what would be the interpretation of the result below

----------------------------------------------------------------
ATT estimation with Nearest Neighbor Matching method
(random draw version)
Analytical standard errors

---------------------------------------------------------
n. treat.   n. contr.         ATT    Std. Err.          t
---------------------------------------------------------

     18893        9532      -0.348        0.007    -48.286

---------------------------------------------------------
Note: the numbers of treated and controls refer to actual
nearest neighbour matches
-----------------------------------------------------------------

Many thanks


Ronnie

Reference

SJ-2-4  st0026  . Est. of average treatment effects based on propensity scores
        (help pscore, attnd, attr, ... if installed)  S. O. Becker & A. Ichino
        Q4/02   SJ 2(4):358--377
        propensity score matching estimators
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