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S7 model specification class

Source: R/zzz-class-model-specification.R
dcm_specification.Rd

The dcm_specification constructor is exported to facilitate the defining of methods in other packages. We do not expect or recommend calling this function directly. Rather, to create a model specification, one should use dcm_specify().

Usage

dcm_specification(
  qmatrix = structure(list(), names = character(0), row.names = integer(0), class =
    "data.frame"),
  qmatrix_meta = list(),
  measurement_model = <object>,
  structural_model = <object>,
  priors = <object>
)

Arguments

qmatrix

A cleaned Q-matrix, as returned by rdcmchecks::clean_qmatrix().

qmatrix_meta

A list of Q-matrix metadata consisting of the other (not Q-matrix) elements returned by rdcmchecks::clean_qmatrix().

measurement_model

A measurement model object.

structural_model

A structural model object.

priors

A prior object.

Value

A dcm_specification object.

See also

dcm_specify()

Examples

qmatrix <- tibble::tibble(
  att1 = sample(0:1, size = 15, replace = TRUE),
  att2 = sample(0:1, size = 15, replace = TRUE),
  att3 = sample(0:1, size = 15, replace = TRUE),
  att4 = sample(0:1, size = 15, replace = TRUE)
)

dcm_specification(qmatrix = qmatrix,
                  qmatrix_meta = list(attribute_names = paste0("att", 1:4),
                                      item_identifier = NULL,
                                      item_names = 1:15),
                  measurement_model = lcdm(),
                  structural_model = unconstrained(),
                  priors = default_dcm_priors(lcdm(), unconstrained()))
#> A loglinear cognitive diagnostic model (LCDM) measuring 4 attributes with
#> 15 items.
#> 
#> ℹ Attributes:
#> 
#> ℹ Attribute structure:
#>   Unconstrained
#> 
#> ℹ Prior distributions:
#>   intercept ~ normal(0, 2)
#>   maineffect ~ lognormal(0, 1)
#>   interaction ~ normal(0, 2)
#>   `Vc` ~ dirichlet()