CAT_ability_est {cat.dt} | R Documentation |
Computes the test taker's estimated ability level based on the CAT decision tree previously built and the test taker's responses to every item at every tree level
CAT_ability_est(cat.dt, res)
cat.dt |
A |
res |
Vector containing the test taker's responses to every item |
A list containing the following elements:
$estimation
Estimated ability level after each level of the tree.
$linf
Lower limit of the final estimation at 95
$lsup
Upper limit of the final estimation at 95
$items
Administered item in each level.
$graphics
Plot object of the evolution of the ability level
estimation. It shows the ability level estimation after the individual
has answered to every administered item.
Javier Rodr?guez-Cuadrado
data("itemBank")
# Build the cat.dt
nodes = CAT_DT(bank = itemBank, model = "GRM", crit = "MEPV",
C = 0.3, stop = c(3,0.5), limit = 200, inters = 0.98,
p = 0.9, dens = dnorm, 0, 1)
# Estimate the ability level of a subject with responses res
estimation = CAT_ability_est(nodes, res = itemRes[1, ])
#plot the estimations
plot(estimation$graphics)