cat_sim: Computerized Adaptive Test (CAT) Simulation

Description

cat_sim function simulates computerized adaptive test (CAT) for one or more simulees. For long simulations, cat_sim_fast function can be used.

Usage

cat_sim(true_ability, cd, verbose = -1)

Value

If the length of true_ability vector is one a

"cat_output" class output will be returned. This is a list containing following elements:

true_ability

True ability (theta) value to generate item responses.

est_history

A list where each element represent a step of the CAT test. It has following elements:

est_before: The estimated ability before the administration of the item.

se_before

The standard error of the estimated ability before the administration of the item.

testlet

TRUE if the item belongs to a testlet.

item

Item-class object that is administered at this step.

resp

The simulated response of the simulee for the item administered at this step using simulee's true_ability value.

est_after

The estimated ability after the administration of the item.

se_after

The standard error of the estimated ability after the administration of the item.

If the length of the true_ability is more than 1, a list of

cat_output objects will be returned for each value of

true_ability.

Arguments

true_ability: True ability vector to generate item responses.
cd: A cat_design object that is created by function create_cat_design.
verbose: This is an integer that will print the stage of the test. For example, if the value verbose = 10, a message will be printed at each tenth iteration of the cat_simulation. Default value is -1, where no message will be printed. If the value is 0, only the start time and end time of the simulation will be printed.

Author

Emre Gonulates

Examples

Run this code

ip <- generate_ip(n = 50)
# Check the default:
cd <- create_cat_design(ip = ip)
cat_sim(true_ability = rnorm(1), cd = cd)

# Multiple theta, optionally set names to the the vector to give examinee IDs
true_theta <- setNames(c(-2, 0.4, 1.5), c("Jimmy", "Ali", "Mirabel"))
cd <- create_cat_design(
  ip = ip,
  ability_est_rule = 'ml',
  termination_rule = c('min_item', 'min_se', 'max_item'),
  termination_par = list(min_item = 10, min_se = .33, max_item = 20))
cat_sim(true_ability = true_theta, cd = cd)