`external` is the only exact GPIRT path. `spline_reference` fits flexible
logistic spline IRFs solely as a nonparametric stress test for conventional
logistic IRF shape; it is deliberately not described as a Gaussian process.
Usage
fit_gpirt(
response_matrix,
engine = c("spline_reference", "external"),
external_engine = NULL,
spline_df = 5L,
...
)
Arguments
- response_matrix
Person-by-item response matrix.
- engine
Estimation engine.
- external_engine
Validated external fitting function.
- spline_df
Degrees of freedom for the spline reference model.
- ...
Additional arguments passed to the selected model, engine, or method.
Value
An object of class "eye_gpirt", stored as a named list, with components "response_matrix", "models", "theta_proxy", "engine", "exact_gpirt", "status", "note". It contains gPIRT model-criticism interface and associated metadata or diagnostics needed to interpret the result.
