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.
loadItemPool(ipar, ipar_se = NULL, unique = FALSE)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'.
(optional) standard errors. Can be a data.frame or the file path of a .csv file.
if TRUE, item IDs must be unique to create a valid item_pool object. (default = FALSE)
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.
dataset_science, dataset_reading, dataset_fatigue, dataset_bayes for 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)
#> [1] TRUE