TwoPLChoicemcmc: Two Parameter Choice IRT Model MCMC

In cIRT: Choice Item Response Theory

Two Parameter Choice IRT Model MCMC

Description

Performs an MCMC routine for a two parameter IRT Model using Choice Data

Usage

TwoPLChoicemcmc(
  unique_subject_ids,
  subject_ids,
  choices_nk,
  fixed_effects,
  B,
  rv_effects_design,
  gamma,
  beta,
  zeta_rv,
  Sigma_zeta_inv,
  Y,
  theta0,
  a0,
  b0,
  mu_xi0,
  Sig_xi0
)

Arguments

unique_subject_ids	A vector with length N \times 1 containing unique subject IDs.
subject_ids	A vector with length NK \times 1 containing subject IDs.
choices_nk	A vector with length NK \times 1 containing subject choices.
fixed_effects	A matrix with dimensions NK \times P_1 containing fixed effect design matrix without theta.
B	A V dimensional column vector relating \theta_i and \zeta_i.
rv_effects_design	A matrix with dimensions NK \times V containing random effect variables.
gamma	A vector with dimensions P \times 1 containing fixed parameter estimates, where P = P_1 + P_2
beta	A vector with dimensions P_2 containing random parameter estimates.
zeta_rv	A matrix with dimensions N \times V containing random parameter estimates.
Sigma_zeta_inv	A matrix with dimensions P_2 \times P_2.
Y	A matrix of dimensions N \times J for Dichotomous item responses
theta0	A vector of length N \times 1 for latent theta.
a0	A vector of length J for item discriminations.
b0	A vector of length J for item locations.
mu_xi0	A vector of dimension 2 (i.e. c(0,1)) that is a prior for item parameter means.
Sig_xi0	A matrix of dimension 2x2 (i.e. diag(2)) that is a prior for item parameter vc matrix.

Value

A list that contains:

ai1

A vector of length J

bi1

A vector of length J

theta1

A vector of length N

Z_c

A matrix of length NK

Wzeta_0

A matrix of length NK

Author(s)

Steven Andrew Culpepper and James Joseph Balamuta

See Also

cIRT(), rmvnorm(), and riwishart()

Examples

## Not run: 
# Call with the following data:
TwoPLChoicemcmc(cogDAT, theta0, a0, b0, mu_xi0, Sig_xi0)

## End(Not run)

cIRT documentation built on Nov. 5, 2025, 7:10 p.m.