Create a Custom Family (Distribution) for use with because

This helper function allows users to easily create custom distribution families by providing the JAGS likelihood code. The function handles S3 method registration.

Usage

because_family(
  name,
  jags_likelihood,
  link = "identity",
  extra_priors = NULL,
  description = NULL
)

Arguments

name

Character string; the name of your family (e.g., "student_t").

jags_likelihood

A character string with the JAGS likelihood code. Use placeholders: {response} for variable name, {mu} for mean, {i} for loop index, {tau} for precision parameter.

link

Link function name (default: "identity"). Options: "identity", "log", "logit".

extra_priors

Character vector of additional JAGS prior statements. Use {response} placeholder for variable-specific naming.

description

Optional description of the family.

Value

A constructor function for the family that can be passed to because(..., family = ...).

Examples

if (FALSE) { # \dontrun{
# Create a Student-t family for robust regression
student_t <- because_family(
  name = "student_t",
  jags_likelihood = "{response}[{i}] ~ dt({mu}[{i}], {tau}, df_{response})",
  extra_priors = c("df_{response} ~ dunif(2, 100)")
)

# Use it
fit <- because(Y ~ X, data = data, family = student_t())
} # }