estimate_gps function

Estimate generalized propensity score (GPS) values

Estimates GPS value for each observation using normal or kernel approaches.

estimate_gps(
  .data,
  .formula,
  gps_density = "normal",
  sl_lib = c("SL.xgboost"),
  ...
)

Arguments

• .data: A data frame of observed continuous exposure variable and observed covariates variable. Also includes id column for future references.
• .formula: A formula specifying the relationship between the exposure variable and the covariates. For example, w ~ I(cf1^2) + cf2.
• gps_density: Model type which is used for estimating GPS value, including normal (default) and kernel.
• sl_lib: A vector of prediction algorithms to be used by the SuperLearner packageg.
• ...: Additional arguments passed to the model.

Returns

The function returns a S3 object. Including the following:

• .data: id, exposure_var, gps, e_gps_pred, e_gps_std_pred, w_resid

• params: Including the following fields:

  • gps_mx (min and max of gps)
  • w_mx (min and max of w).
  • .formula
  • gps_density
  • sl_lib
  • fcall (function call)

Examples

m_d <- generate_syn_data(sample_size = 100)
data_with_gps <- estimate_gps(.data = m_d,
                              .formula = w ~ cf1 + cf2 + cf3 + cf4 + cf5 + cf6,
                              gps_density = "normal",
                              sl_lib = c("SL.xgboost")
                             )