loadItemPool {TestDesign}

Load item pool

Description

loadItemPool is a data loading function for creating an item_pool object. loadItemPool can read item parameters and standard errors from a data.frame or a .csv file.

Usage

loadItemPool(ipar, ipar_se = NULL, unique = FALSE)

Arguments

ipar

item parameters. Can be a data.frame or the file path of a .csv file. The content should at least include columns 'ID' and 'MODEL'.

ipar_se

(optional) standard errors. Can be a data.frame or the file path of a .csv file.

unique

if TRUE, item IDs must be unique to create a valid item_pool object. (default = FALSE)

Value

loadItemPool returns an item_pool object.

• ni the number of items in the pool.

• max_cat the maximum number of response categories across all items in the pool.

• index the numeric item index of each item.

• id the item ID string of each item.

• model the object class names of each item representing an item model type. Can be item_1PL, item_2PL, item_3PL, item_PC, item_GPC, or item_GR.

• NCAT the number of response categories of each item.

• parms a list containing the item object of each item.

• ipar a matrix containing all item parameters.

• se a matrix containing all item parameter standard errors. The values will be 0 if the argument ipar_se was not supplied.

• raw the original input data.frame used to create this object.

See Also

dataset_science, dataset_reading, dataset_fatigue, dataset_bayes for examples.

Examples

## Read from data.frame:
itempool_science <- loadItemPool(itempool_science_data)

## Read from file: write to tempdir() for illustration and clean afterwards
f <- file.path(tempdir(), "itempool_science.csv")
write.csv(itempool_science_data, f, row.names = FALSE)
itempool_science <- loadItemPool(f)
file.remove(f)