irt (version 0.2.9)

summary.cat_output: Summarizes the raw output of cat_sim

Description

This function summarizes a list consist of cat_output objects. It returns a summary data frame of the CAT simulation.

Usage

# S3 method for cat_output
summary(
  object,
  ...,
  cols = c("examinee_id", "true_ability", "est_ability", "se", "test_length")
)

Value

This function returns a summary data frame of adaptive tests. Each row will represent a different adaptive test.

Arguments

object

This is a cat_output object or a list object containing elements that are "cat_output" class.

...

Additional arguments.

cols

The variables that will be included in the summary. There should be at least one column. Available columns are:

examinee_id

Examinee ID's if named true theta vector has been provided to cat_sim() function.

true_ability

True ability of the simulee

est_ability

Ability Estimate

se

Standard Error of the ability estimate

test_length

Test length.

bias

The difference between true ability and ability estimate

mse

Mean squared error

mean_qip

Mean of Quality of Item Pool Index. See qip_index() function for details.

median_qip

Median of Quality of Item Pool Index. See qip_index() function for details.

min_qip

Minimum value of Quality of Item Pool Index. See qip_index() function for details.

max_qip

Maximum value of Quality of Item Pool Index. See qip_index() function for details.

Author

Emre Gonulates

See Also

cat_sim

Examples

n <- 100 # number of items
ip <- generate_ip(n = n,
                  content = sample(c("Algebra", "Arithmetic", "Geometry"),
                                   n, replace = TRUE))
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(5), cd = cd)
summary(cat_data)

# Get only selected columns
summary(cat_data, cols = c("examinee_id", "true_ability", "est_ability",
                           "bias"))
summary(cat_data, cols = c("examinee_id", "true_ability", "est_ability",
                           "mean_qip", "median_qip", "min_qip"))