irc.bairt {bairt} | R Documentation |
Plot of the j-th item
response curve.
## S3 method for class 'bairt' irc(mcmclist, item = 1, color = "red", prob = c(0.05, 0.95), ...)
mcmclist |
A mcmc.2pnob or mcmc.3pnob class object. |
item |
The number of j-th item. |
color |
Item response curve color. |
prob |
A vector of length two for defined the percentiles of the posterior density. |
... |
Further arguments. |
The solid line corresponds to the location of the posterior mean and the points correspond to the percentiles determined by prob. prob = c(0.05, 0.95) corresponds to the 5th and 95th percentils of the posterior density respectively.
Plot of the j-th item
response curve.
Javier MartÃnez
Johnson, V. E. & Albert, J. H. (1999). Ordinal Data Modeling. New York: Springer.
mcmc.2pnob
, mcmc.3pnob
and
continue.mcmc.bairt
.
# data for model data("MathTest") # Only for the first 500 examinees of the data MathTest # Two-Parameter Normal Ogive Model model2 <- mcmc.2pnob(MathTest[1:500,], iter = 400, burning = 100) check.plot(model2) irc(model2, item = 3) # For all examinees of the data MathTest # Three-Parameter Normal Ogive Model # selection of the prior for 5 response options cprior <- select.c.prior(5) modelAll3 <- mcmc.3pnob(MathTest, iter = 1000, burning = 0, c.prior = cprior) irc(modelAll3 , item = 1, color = "blue") irc(modelAll3 , item = 1, color = "blue", prob = c(0.1, 0.9)) ## End(Not run)