expected.test: Function to calculate expected test score

Description Usage Arguments References See Also Examples

View source: R/expected.test.R

Description

Given an estimated model compute the expected test score. Returns the expected values in the same form as the data used to estimate the model.

Usage

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expected.test(x, Theta, group = NULL, mins = TRUE, individual = FALSE,
  which.items = NULL)

Arguments

x

an estimated mirt object

Theta

a matrix of latent trait values

group

a number signifying which group the item should be extracted from (applies to 'MultipleGroupClass' objects only)

mins

logical; include the minimum value constants in the dataset. If FALSE, the expected values for each item are determined from the scoring 0:(ncat-1)

individual

logical; return tracelines for individual items?

which.items

an integer vector indicating which items to include in the expected test score. Default uses all possible items

References

Chalmers, R., P. (2012). mirt: A Multidimensional Item Response Theory Package for the R Environment. Journal of Statistical Software, 48(6), 1-29. doi: 10.18637/jss.v048.i06

See Also

expected.item

Examples

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## Not run: 
dat <- expand.table(deAyala)
model <- 'F = 1-5
          CONSTRAIN = (1-5, a1)'
mod <- mirt(dat, model)

Theta <- matrix(seq(-6,6,.01))
tscore <- expected.test(mod, Theta)
tail(cbind(Theta, tscore))

# use only first two items (i.e., a bundle)
bscore <- expected.test(mod, Theta, which.items = 1:2)
tail(cbind(Theta, bscore))


## End(Not run)

xzhaopsy/MIRT documentation built on May 29, 2019, 12:42 p.m.