Calculates the next item to administer in an adaptive test to measure the D-score. Uses the previously administered items and item scores as input.

Calculates the next item to administer in an adaptive test to measure the D-score. Uses the previously administered items and item scores as input.

Usage

dcat_next(
  txt = "",
  instrument = "gs1",
  key = NULL,
  p = 50,
  session = "",
  format = "3.1",
  ...
)

Arguments

txt

A JSON string, URL or file

instrument

character vector with instrument names to use to select items

key

String. They key identifies 1) the difficulty estimates pertaining to a particular Rasch model, and 2) the prior mean and standard deviation of the prior distribution for calculating the D-score. The default key NULL sets key = "gsed2510". View dscore::builtin_keys for an overview of the available keys.

p

percentage to pass the item, difficulty in percentile units

session

Optional session key if data is already uploaded to sitehost.

format

String. JSON data schema version number. There are currently three schemas supported: "1.0", "1.1", "2.0", "3.0" and "3.1". Formats "1.0" and "1.1" are included for backward compatibility only. Use format = "3.1" for new applications.

...

Ignored

Value

A string of milestones

Author

Iris Eekhout 2025

Examples

txt <- system.file("examples", "example_v3.1.json", package = "bdsreader")
dcat_next(txt = txt, p = 50)
#> [1] "gs1lgc110"