dot-fit_gps_model: Fit a natural-spline treatment model and return the GPS model...

In RobustMediate: Causal Mediation Analysis with Diagnostics and Sensitivity Analysis

Fit a natural-spline treatment model and return the GPS model object

Description

Fit a natural-spline treatment model and return the GPS model object

Usage

.fit_gps_model(treatment_formula, data, df = 4, family = stats::gaussian())

Arguments

treatment_formula	Original treatment formula (e.g., X ~ Z1 + Z2).
data	Data frame.
df	Degrees of freedom for splines::ns(). Default 4.
family	GLM family. Default gaussian().

Value

A fitted glm object with a spline basis for the intercept term replaced by ns(X, df) on the response side — i.e. the model X_spline ~ Z where X_spline is the ns-expanded treatment. In practice we use the approach: model X | Z with a Gaussian GLM using the raw X, then use the residual SD from that model to form GPS densities. The spline enters on the covariate side of mediator/outcome models for the dose-response curve.

RobustMediate documentation built on April 16, 2026, 5:08 p.m.