An dxwts object.

An indicator of which type of plot is desired. The options are

• "optimize" or 1 A plot of the balance criteria as a function of the GBM iteration.

• "boxplot" or 2 Boxplots of the propensity scores for the treatment and control cases

• "es" or 3 Plots of the standardized effect size of the pre-treatment variables before and after reweighing

• "t" or 4 Plots of the p-values from t-statistics comparing means of treated and control subjects for pretreatment variables, before and after weighting.

• "ks" or 5 Plots of the p-values from Kolmogorov-Smirnov statistics comparing distributions of pretreatment variables of treated and control subjects, before and after weighting.

Additional arguments.