How do I compare covariates between treatment and control groups (to see if there is no difference) after using 1:1 nearest neighbor matching

[Sanjay Sharma]

I am trying to use one to one matching with replacement using nearest neighbor matching in order to estimate the effect of "TreatmentX", using a caliper of 0.5 SD. I want to see difference in "OutcomeY" between treatment groups (TreatmentX = 0 Vs 1) after matching based on following variables: age, education, male, farmsize, employment, hh_type.

To estimate the effect of "TreatmentX" on "OutcomeY", I used the following command:

teffects nnmatch (OutcomeY age education male farmsize employment hh_type) (TreatmentX) , atet biasadj ( age education farmsize) ematch (male) dmvariables nneighbor(1) caliper(0.5)

The above command gives me the ATT of "TreatmentX" on "OutcomeY" after controlling for the above mentioned variables.

Now that matching has been done, I would like to see if there is no difference in above mentioned covariates between treatment and control group. However, I am struggling to see how this can be done when we use nnmatch command. I have been told that commands like kmatch-, -ultimatch- and -vmatch can be used in this case, but have no idea how to do it. Can anybody help with this?

Thank you in advance for taking time out and responding to my post.

* Example generated by -dataex-. To install: ssc install dataex
clear
input byte TreatmentX float ( OutcomeY age education male farmsize employment hh_type)
0    188000 42 10 1  .625 1 1
1     22250 50 10 1 1.125 0 1
1    318000 54 10 1  .625 0 1
1    469100 51 10 1   .05 1 1
1     51500 68  9 1    .6 0 1
1    209645 63 10 1    .7 0 1
0    278400 72 10 1    .9 1 1
1    277000 61 10 1  .875 1 1
1    218670 45 12 0 .8125 0 1
0     91000 27  8 0  .375 1 1
1    221500 39 10 1  .025 1 1
1     84875 46 12 0   2.7 0 1
1    300980 40 12 1  .875 1 1
1     84120 48  5 0     1 0 1
0         0 34 10 1  .375 0 1
0     45000 68 10 1  1.25 0 1
0         0 48  8 1    .1 0 1
0     16000 63  2 1  .125 1 1
1     79000 46  8 1  .375 1 1
0    103750 60  4 1    .5 1 1
1     70150 74  7 1    .5 0 1
1     82075 42  2 1  .125 1 1
0    700000 80  0 1   .75 0 1
0    109500 55  5 1 .1875 1 1
0    209800 26  7 1 .5625 1 1
1 293051.75 30  5 0  .125 0 1
0     25200 43  0 0   .25 0 1
0     72400 25  7 0 .0625 0 1
0     33200 49  2 1   .25 1 1
1     39600 51  6 1 1.125 1 1
1    466375 51  2 0   .45 0 1
1     55500 35  0 0    .5 1 1
1    283900 56  7 1   .95 0 1
end