dx.wts: Propensity score diagnostics
In twang: Toolkit for Weighting and Analysis of Nonequivalent Groups

Description Usage Arguments Details Value See Also

dx.wts takes a ps object or a set of propensity scores and computes diagnostics assessing covariates balance.

dx.wts(x,
       data,
       estimand,
       vars=NULL,
       treat.var,
       x.as.weights=TRUE,
       sampw=NULL,
       perm.test.iters=0)

`x`	a data frame, matrix, or vector of propensity score weights or a ps object. `x` can also be a data frame, matrix, or vector of propensity scores if `x.as.weights=FALSE`
`data`	a data frame
`estimand`	the estimand of interest: either "ATT" or "ATE"
`vars`	a vector of character strings naming variables in `data` on which to assess balance
`treat.var`	a character string indicating which variable in `data` contains the 0/1 treatment group indicator
`x.as.weights`	`TRUE` or `FALSE` indicating whether `x` specifies propensity score weights or propensity scores. Ignored if `x` is a ps object
`sampw`	optional sampling weights. If `x` is a ps object then the sampling weights should have been passed to `ps` and not specified here. `dx.wts` will issue a warning if `x` is a ps object and `sampw` is also specified
`perm.test.iters`	an non-negative integer giving the number of iterations of the permutation test for the KS statistic. If `perm.test.iters=0` then the function returns an analytic approximation to the p-value. This argument is ignored is `x` is a `ps` object. Setting `perm.test.iters=200` will yield precision to within 3% if the true p-value is 0.05. Use `perm.test.iters=500` to be within 2%

Creates a balance table that compares unweighted and weighted means and standard deviations, computes effect sizes, and KS statistics to assess the ability of the propensity scores to balance the treatment and control groups.

Returns a list containing

`treat`	the vector of 0/1 treatment assignment indicators
`desc`	a nested list containing detailed diagnostic information on the weights. This includes the number of treatment and control subjects, the effective sample size, the largest KS statistic, the average absolute effect size, and the complete balance table
`summary.tab`	a data frame showing balance information
`ps`	the given propensity scores
`w`	the given weights
`datestamp`	the date and time of the call to `dx.wts`
`parameters`	the parameters used when calling `dx.wts`
`alerts`	text containing any warnings accumulated during the estimation
`varNames`	the variable names