fit_TIRT_stan: Fit Thurstonian IRT models in Stan

Description Usage Arguments Value Examples

View source: R/stan.R

Description

Fit Thurstonian IRT models in Stan

Usage

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fit_TIRT_stan(data, init = 0, ...)

Arguments

data

An object of class 'TIRTdata'. see make_TIRT_data for documentation on how to create one.

init

Initial values of the parameters. Defaults to 0 as it proved to be most stable.

...

Further arguments passed to rstan::sampling.

Value

A 'TIRTfit' object.

Examples

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# load the data
data("triplets")

# define the blocks of items
blocks <-
  set_block(c("i1", "i2", "i3"), traits = c("t1", "t2", "t3"),
          signs = c(1, 1, 1)) +
  set_block(c("i4", "i5", "i6"), traits = c("t1", "t2", "t3"),
            signs = c(-1, 1, 1)) +
  set_block(c("i7", "i8", "i9"), traits = c("t1", "t2", "t3"),
            signs = c(1, 1, -1)) +
  set_block(c("i10", "i11", "i12"), traits = c("t1", "t2", "t3"),
            signs = c(1, -1, 1))

# generate the data to be understood by 'thurstonianIRT'
triplets_long <- make_TIRT_data(
  data = triplets, blocks = blocks, direction = "larger",
  format = "pairwise", family = "bernoulli", range = c(0, 1)
)


# fit the data using Stan
fit <- fit_TIRT_stan(triplets_long, chains = 1)
print(fit)
predict(fit)

thurstonianIRT documentation built on Aug. 9, 2019, 5:07 p.m.