Compute standardized mean differences (SMDs) between the treated and control subjects. Computed as \((\mu_t - \mu_c)/\sigma\) where \(\mu_t\) is the weighted mean among the treated subjects, \(\mu_c\) is the weighted mean among the control subjects, and \(\sigma\) is the standard deviation in the unweighted sample (among the treated subjects only since we are interested in the average treatment effect for the treated).
smd(object, ...) # S3 method for grouped_psweight_mi smd(object, x_vars = NULL)
object | An object of the appropriate class. |
---|---|
x_vars | A character vector containing the covariates used to check
for balance. These must be columns in |
A smd
object that inherits from dplyr::tibble
. The following
columns are always returned:
A variable - either a covariate or the propensity score.
The propensity score method.
The (weighted) mean among the controls.
The (weighted) mean among the treated.
The standard deviation among the treated.
The standardized mean difference.
In addition, a column for the group included if object
is grouped and the
column imp
is included if object
was instantiated from a propensity
score fit using multiply imputed datasets.