get_parameters {measr}

Get a list of possible parameters

Description

When specifying prior distributions, it is often useful to see which parameters are included in a given model. Using the Q-matrix and type of diagnostic model to estimated, we can create a list of all included parameters for which a prior can be specified.

Usage

get_parameters(
  qmatrix,
  item_id = NULL,
  rename_att = FALSE,
  rename_item = FALSE,
  type = c("lcdm", "dina", "dino", "crum"),
  attribute_structure = c("unconstrained", "independent")
)

Arguments

qmatrix

The Q-matrix. A data frame with 1 row per item and 1 column per attribute. All cells should be either 0 (item does not measure the attribute) or 1 (item does measure the attribute).

item_id

Optional. Variable name of a column in qmatrix that contains item identifiers. NULL (the default) indicates that no identifiers are present in the Q-matrix.

rename_att

Should attribute names from the qmatrix be replaced with generic, but consistent names (e.g., "att1", "att2", "att3").

rename_item

Should item names from the qmatrix be replaced with generic, but consistent names (e.g., 1, 2, 3).

type

Type of DCM to estimate. Must be one of lcdm, dina, dino, or crum.

attribute_structure

Structural model specification. Must be one of unconstrained, or independent. unconstrained makes no assumptions about the relationships between attributes, whereas independent assumes that proficiency statuses on attributes are independent of each other.

Value

A tibble with one row per parameter.

Examples

get_parameters(ecpe_qmatrix, item_id = "item_id", type = "lcdm")

get_parameters(ecpe_qmatrix, item_id = "item_id", type = "lcdm",
               rename_att = TRUE)