irt (version 0.2.9)

$.cat_output: Prints the raw output of cat_sim

Description

This function prints a data frame that shows all of the steps of a CAT for a single examinee.

Usage

# S3 method for cat_output
$(x, name)

Value

See the 'name' argument above for possible return values.

Arguments

x

This is a cat_output object which has "cat_output" class.

name

Name of the field. Available options:

"ip"

Extract items administered to examinee

"resp"

Extract responses

"testlet"

Extract testlets administered

"est_before"

Extract ability estimate before administration of an item.

"item_id"

Extract administered item IDs.

"est_after"

Extract ability estimate after administration of an item.

"se_before"

Extract standard error before administration of an item.

"se_after"

Extract standard error after administration of an item.

"true_theta"

Extract true theta as a vector

"test_length"

Extract test length of the adaptive test

"final_est"

Extract final ability estimate.

"final_se"

Extract final standard error.

Author

Emre Gonulates

See Also

cat_sim

Examples

n <- 20 # number of items
ip <- generate_ip(n = n)
cd <- create_cat_design(ip = ip, next_item_rule = 'mfi',
                        termination_rule = 'max_item',
                        termination_par = list(max_item = 10))
cat_data <- cat_sim(true_ability = rnorm(1), cd = cd)
cat_data
cat_data$resp # Extract responses to administered items
cat_data$ip # Administered items
cat_data$item_id # Extract administered item IDs
cat_data$est_before # Ability estimates before the administration of an item
cat_data$est_after # Ability estimates after the administration of an item
cat_data$true_theta # True ability that generates examinee responses

# Simulation with more than one simulees
n <- 20 # number of items
ip <- generate_ip(n = n)
cd <- create_cat_design(ip = ip, next_item_rule = 'mfi',
                        termination_rule = 'max_item',
                        termination_par = list(max_item = 10))
n_examinee <- 3
cat_data_list <- cat_sim(true_ability = rnorm(n_examinee), cd = cd)
cat_data_list[[3]]$item_id
cat_data_list[[2]]$item_id
cat_data_list[[3]]$resp
cat_data_list[[2]]$resp
cat_data_list[[2]]$test_length
cat_data_list[[2]]$final_est
cat_data_list[[2]]$final_se