solver: The Solver for Deriving Model Predictions

In dRiftDM: Estimating (Time-Dependent) Drift Diffusion Models

The Solver for Deriving Model Predictions

Description

Functions to get or set the "solver" of an object. The "solver" controls the method for deriving the model's first passage time (i.e., its predicted PDFs).

Usage

solver(object, ...) <- value

## S3 replacement method for class 'drift_dm'
solver(object, ..., eval_model = FALSE) <- value

solver(object, ...)

## S3 method for class 'drift_dm'
solver(object, ...)

## S3 method for class 'fits_ids_dm'
solver(object, ...)

Arguments

object	an object of type drift_dm or fits_ids_dm (see load_fits_ids).
...	additional arguments (i.e., eval_model).
value	a single character string, providing the new "solver" (i.e., approach to derive the first passage time; see drift_dm()).
eval_model	logical, indicating if the model should be re-evaluated or not when updating the solver (see re_evaluate_model). Default is FALSE.

Details

solver() is a generic accessor function, and ⁠solver<-()⁠ is a generic replacement function. The default methods get and set the "solver".

The "solver" indicates the approach with which the PDFs of a model are calculated. Supported options are "kfe" and "im_zero" (method based on the Kolmogorov-Forward-Equation or on integral equations, respectively). Note that "im_zero" is only supported for models that assume a fixed starting point from 0.

Value

For solve() the string solver (see drift_dm()).

For ⁠solver<-()⁠ the updated drift_dm object.

Note

There is only a replacement function for drift_dm objects. This is because replacing the approach for deriving PDFs after the model has been fitted (i.e., for a fits_ids_dm object) doesn't make sense.

See Also

drift_dm()

Examples

# get some default model to demonstrate the solver() functions
my_model <- ratcliff_dm()
solver(my_model)
# change to the integral approach
solver(my_model) <- "im_zero"
solver(my_model)

# accessor method also available for fits_ids_dm objects
# (see estimate_model_ids)
# get an exemplary fits_ids_dm object
fits <- get_example_fits_ids()
solver(fits)

dRiftDM documentation built on April 3, 2025, 7:48 p.m.