theta_FB {TestDesign}

(C++) Calculate a theta estimate using FB (Full Bayes) method

Description

theta_FB_single() and theta_FB() are functions for calculating a theta estimate using FB (Full Bayes) method.

Usage

theta_FB(
  nx,
  theta_init,
  theta_prop,
  items_list,
  item_init,
  resp,
  ncat,
  model,
  prior,
  prior_parm
)

theta_FB_single(
  nx,
  theta_init,
  theta_prop,
  item_mcmc,
  item_init,
  resp,
  ncat,
  model,
  prior,
  prior_parm
)

Arguments

nx

the number of MCMC draws.

theta_init

the initial estimate to use.

theta_prop

the SD of the proposal distribution.

item_init

item parameter estimates. Must be a vector for theta_FB_single(), and a matrix for theta_FB().

resp

a vector containing responses on each item.

ncat

a vector containing the number of response categories of each item.

model

a vector indicating item models of each item, using

• 1: 1PL model

• 2: 2PL model

• 3: 3PL model

• 4: PC model

• 5: GPC model

• 6: GR model

prior

an integer indicating the type of prior distribution, using

• 1: normal distribution

• 2: uniform distribution

prior_parm

a vector containing parameters for the prior distribution.

item_mcmc, items_list

sampled item parameters. Must be a matrix for theta_FB_single(), and a list of matrices for theta_FB().

Details

theta_FB_single() is designed for one item, and theta_FB() is designed for multiple items.

Currently supports unidimensional models.