runEquateObserved function

Run Test Equating

runEquateObserved is a function for performing equipercentile equating between two scales. runEquateObserved also produces a concordance table, mapping the observed raw scores from one scale to the scores from another scale.

runEquateObserved(
  data,
  scale_from = 2,
  scale_to = 1,
  type_to = "raw",
  rsss = NULL,
  eq_type = "equipercentile",
  smooth = "loglinear",
  degrees = list(3, 1),
  boot = TRUE,
  reps = 100,
  verbose = FALSE,
  ...
)

Arguments

• data: a PROsetta_data object. See loadData for loading a dataset.
• scale_from: the scale ID of the input scale. References to itemmap in data argument. (default = 2)
• scale_to: the scale ID of the target scale to equate to. References to itemmap in data argument. (default = 1)
• type_to: the type of score to use in the target scale frequency table. Accepts raw, tscore, and theta. tscore and theta require argument rsss to be supplied. (default = raw)
• rsss: the RSSS table to use to map each raw score level onto a t-score or a theta. See runRSSS.
• eq_type: the type of equating to be passed onto equate in 'equate' package. (default = equipercentile)
• smooth: the type of smoothing method to be passed onto presmoothing in 'equate' package. (default = loglinear)
• degrees: the degrees of smoothing to be passed onto presmoothing. (default = list(3, 1))
• boot: performs bootstrapping if TRUE. (default = TRUE)
• reps: the number of replications to perform in bootstrapping. (default = 100)
• verbose: if TRUE, print status messages. (default = FALSE)
• ...: other arguments to pass onto equate.

Returns

runEquateObserved returns an equate object containing the test equating result.

The printed summary statistics indicate the distributional properties of the two supplied scales and the equated scale.

• x corresponds to scale_from.
• y corresponds to scale_to.
• yx corresponds to scale_from after equating to scale_to.

See equate for details.

The concordance table is stored in concordance slot.

Examples

out_eq_raw <- runEquateObserved(data_asq,
  scale_to = 1, scale_from = 2,
  eq_type = "equipercentile", smooth = "loglinear"
)
out_eq_raw$concordance

out_link <- runLinking(data_asq, method = "FIXEDPAR")
out_rsss <- runRSSS(data_asq, out_link)
out_eq_tscore <- runEquateObserved(data_asq,
  scale_to = 1, scale_from = 2,
  type_to = "tscore", rsss = out_rsss,
  eq_type = "equipercentile", smooth = "loglinear"
)
out_eq_tscore$concordance