CAT_ability_est_group {cat.dt}R Documentation

Ability level estimation for a group using a CAT decision tree


Computes the test takers' estimated ability level based on the CAT decision tree previously built and the test takers' responses to every item at every tree level


CAT_ability_est_group(cat.dt, res)



A cat.dt object returned by CAT_DT.


Matrix containing the test takers' responses to every item. Rows represent each individual and columns represent the responses given to each item


A list of lists containing the following elements for each individual:

$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 Rodríguez-Cuadrado


# data("itemBank")
# Build the cat.dt
# nodes = CAT_DT(bank = itemBank, model = "GRM", crit = "MEPV",
#                C = 0.3, stop = c(2, 0.5), limit = 100, inters = 0.8,
#                p = 0.8, dens = dnorm, 0, 1)

# Estimate the ability level of a subject with responses res
# CAT_ability_est_group(nodes, res = itemRes)

[Package cat.dt version 0.3.1 Index]