summary.pifit {pairwise}R Documentation

S3 Summary for Item-Fit-Statistics

Description

S3 summary method for object of classc("pifit", "data.frame" )

Usage

## S3 method for class 'pifit'
summary(
  object,
  sort = FALSE,
  by = "INFIT.ZSTD",
  decreasing = FALSE,
  relative = FALSE,
  ...
)

Arguments

object

object of class"pifit", "data.frame"

sort

logical with default sort=FALSE - if set to sort=TRUE items are ordered by absolute FIT.

by

character passing the type of Fit-Statistic to sort by - ignored when sort=FALSE. valid options are: "INFIT.ZSTD" (default), "OUTFIT.MSQ", "OUTFIT.ZSTD" and "INFIT.MSQ".

decreasing

see order

relative

logical with default relative=FALSE to return the fit statistics as proposed by Wright & Masters, (1982, P. 100) with no further modifications. If relative=TRUE the sample adjusted fit statistics are returned in a way that their mean (for the present sample) equals 1 using formula: fit_i+ = 1 – mean(fit).

...

other parameters passed trough - see order

References

Wright, B. D., & Masters, G. N. (1982). Rating Scale Analysis. Chicago: MESA Press.

Wright, B. D., & Masters, G. N. (1990). Computation of OUTFIT and INFIT Statistics. Rasch Measurement Transactions, 3(4), 84–85.


[Package pairwise version 0.6.1-0 Index]