Evaluates frequencies and discrimination parameters of codes and categories

Usage

evaluate_psychometrics(
  design_coded,
  units,
  domains = NULL,
  max_n_categories = 10,
  overwrite = FALSE,
  identifiers = c("group_id", "login_name", "login_code")
)

Arguments

design_coded: Tibble. Response data within the design merged by complete_design().
units: Tibble. Unit data retrieved from the IQB Studio after setting the argument metadata = TRUE for get_units() – otherwise the item values could only be inferred from the variable source tree, i.e., item scores are taken from variable scores that are no source variables for other derived variables. Could optionally also contain unit_codes prepared by add_coding_scheme() (saves some time).
domains: Tibble. Contains columns domain and unit_key. Currently, the routine only works for one-dimensional domain, i.e., there is only one domain for each unit_key. If not specified, the workspace_label is regarded as the unit domain.
max_n_categories: Tibble. Maximum number of categories to check for category frequencies for list values, e.g., [[01_1,01_2]]. Defaults to 10.
overwrite: Logical. Should column unit_codes be overwritten if they exist on units. Defaults to FALSE, i.e., unit_codes will be used if they were added to units beforehand by applying add_coding_schemes().
identifiers: Character. Contains person identifiers of the dataset coded. Defaults to c("group_id", "login_name", "login_code") which corresponds to the identifiers of the IQB Testcenter.

Value

A tibble.

Details

This function estimates item, code and category frequencies for a set of coded responses. Please note that cases that are not used will be eliminated prior to the anaylsis.