st: Propensity score balancing property

[Orrin Pail <orrinpail@gmail.com>]

Hello,

I am trying to use pscore for propensity matching analysis and I am
having difficulties in satisfying the balancing property.

My covariates (xlist below) include 8 different variables. I have been
trying different combinations of them, sometimes removing some, adding
others. I also tried including interaction terms into my xlist but
stata says that they are not allowed. No matter what I do, my
balancing property is not being met.

The closest I get to satisfying the balancing property is when I use
five of the variables. In this case, the output says that the final
number of blocks is 8 and that three of the variables (they are listed
separately) are not balanced in block 7.

Does anyone have any recommendations on how I can satisfy the
balancing property besides adding more variables? From what I
understand, my propensity score analysis would be useless without the
balancing property being met, so I would appreciate all the help!

The command I am using is below (I defined treatment and xlist prior
to this command):

pscore $treatment $xlist, pscore(myscore) blockid(myblock) comsup

Thanks!

Orrin
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