summary.meqc {equateIRT} | R Documentation |
Summarizing Bisector Equating Coefficients
Description
summary
method for class meqc
.
Usage
## S3 method for class 'meqc'
summary(object, ...)
## S3 method for class 'summary.meqc'
print(x, ...)
Arguments
object |
an object of the class |
x |
an object of class |
... |
further arguments passed to or from other methods. |
Value
The function summary.meqc
returns a list with components
link |
character vector with names of equated forms. |
method |
the equating method used. |
coefficients |
list of data frames containing |
Author(s)
Michela Battauz
See Also
Examples
# the following code uses item parameter estimates previously obtained
# for examples that start from item response data see function modIRT
# three-parameter logistic model
# direct equating coefficients using the "Stocking-Lord" method
data(est3pl)
test <- paste("test", 1:5, sep = "")
mod3pl <- modIRT(coef = est3pl$coef, var = est3pl$var, names = test, display = FALSE)
direclist3pl <- alldirec(mods = mod3pl, method = "Stocking-Lord")
# compute chain equating coefficients for path 1,2,3,4
pth1 <- paste("test", 1:4, sep = "")
pth1 <- data.frame(t(pth1), stringsAsFactors = FALSE)
chainec1 <- chainec(direclist = direclist3pl, pths = pth1)
# compute chain equating coefficients for path 1,5,4
pth2 <- c(paste("test", c(1,5,4), sep = ""))
pth2 <- data.frame(t(pth2), stringsAsFactors = FALSE)
chainec2 <- chainec(direclist = direclist3pl, pths = pth2)
# compute chain equating coefficients for path 1,2,3,4,5
pth3 <- paste("test", 1:5, sep = "")
pth3 <- data.frame(t(pth3), stringsAsFactors = FALSE)
chainec3 <- chainec(direclist = direclist3pl, pths = pth3)
# create a list of objects of class eqc or ceqc
ecall <- c(chainec1, chainec2, chainec3, direclist3pl["test1.test5"])
# compute bisector and weighted bisector coefficients
allec <- bisectorec(ecall = ecall, weighted = TRUE, unweighted = TRUE)
summary(allec)
[Package equateIRT version 2.5.0 Index]