Does the teffects suite of commands include a command showing how many records at each treatment level are used to estimate treatment effects?
Here is an example illustrating the source of my confusion.
In this example, mbsmoke is the treatment indicator and 864 of 4,642 records receive treatment. The nearest-neighbor estimator applies 1-1 matching and estimates an ATE of approximately -240. I believe that 864 treated units (mbsmoke==1) and some number of matched control units (mbsmoke==0) are used to generate the ATE of approximately -240. Does the teffects suite of commands include a command showing how many records at each treatment level are used to estimate the treatment effect of approximately -240?
Here is an example illustrating the source of my confusion.
Code:
. use http://www.stata-press.com/data/r13/cattaneo2, clear
(Excerpt from Cattaneo (2010) Journal of Econometrics 155: 138-154)
. tab mbsmoke
1 if mother |
smoked | Freq. Percent Cum.
------------+-----------------------------------
nonsmoker | 3,778 81.39 81.39
smoker | 864 18.61 100.00
------------+-----------------------------------
Total | 4,642 100.00
. teffects nnmatch (bweight mage prenatal1 mmarried fbaby) (mbsmoke), nn(1)
Treatment-effects estimation Number of obs = 4,642
Estimator : nearest-neighbor matching Matches: requested = 1
Outcome model : matching min = 1
Distance metric: Mahalanobis max = 139
----------------------------------------------------------------------------------------
| AI Robust
bweight | Coef. Std. Err. z P>|z| [95% Conf. Interval]
-----------------------+----------------------------------------------------------------
ATE |
mbsmoke |
(smoker vs nonsmoker) | -240.3306 28.43006 -8.45 0.000 -296.0525 -184.6087
----------------------------------------------------------------------------------------
.
.
. tebalance summarize
note: refitting the model using the generate() option
Covariate balance summary
Raw Matched
-----------------------------------------
Number of obs = 4,642 9,284
Treated obs = 864 4,642
Control obs = 3,778 4,642
-----------------------------------------
-----------------------------------------------------------------
|Standardized differences Variance ratio
| Raw Matched Raw Matched
----------------+------------------------------------------------
mage | -.300179 -.0040826 .8818025 .9815517
prenatal1 | -.3242695 -2.78e-16 1.496155 1
mmarried | -.5953009 -2.42e-16 1.335944 1
fbaby | -.1663271 2.24e-16 .9430944 1
-----------------------------------------------------------------
