The purpose of this investigation was to study the
nature of the item and ability estimates obtained when
the modified three-parameter logistic model is used
with two-dimensional data. To examine the effects of
The θ scale in item response theory has arbitrary
unit and origin. When a group of items is calibrated
twice, estimates from one calibration must be transformed
to the metric of the other. A new method is
presented for ...
A "mixture" probability model that incorporates
two component models defined by nonsubsuming sets
of parameters is introduced, and a strategy for using
this model in the selection of a preferred component
model is ...
Computer programs for fitting latent trait models to
data provide indices of item misfit. An analysis of the
consistency of item misfit determination is presented.
Two content-equivalent forms of 71 items representing
For purposes of evaluating INDSCAL’s goodness-of-fit index (R₁), random data were generated for various
combinations of N (the number of individuals),
ranging from 3 to 30, and n (the number of stimuli),
ranging from ...