Problem with the probit regression that "psmatch2" estimates

Dear Statalist,

I am confused because of the output I am getting out of the command psmatch2. Specifically, I wanted to get the same result for the probit model that the command uses for estimating the propensity score by using the command "probit" myself, but I am not getting the same results, even though I am using the same list of covariates. I am running the following two lines of code:

probit D_Credit1 $xlist
psmatch2 D_Credit1 $xlist, outcome(Q_cul2_m_ln)

where D_Credit1 is the variable whose impact on Q_cul2_m_ln I am trying to calculate. Xlist contains the list of covariates that I used for estimating the pscore. The problem is, as you can see, the probit regression estimated with the command "probit" uses 24378 observations, while the one estimated by the command "psmatch2" uses only 11122 observations, and of course the results of these 2 are not the same. So my question is: does anybody have a clue of why are these 2 probit regressions not giving me the exact same results, even though they are supposedly using the same dependent and independent variables?

Thank you in advance for your help.

Best regards


This is the output from
probit D_Credit1 $xlist Array



This is the output from
psmatch2 D_Credit1 $xlist, outcome(Q_cul2_m_ln) Array