The purpose of the present research was to develop
general guidelines to assist practitioners in setting up
operational computerized adaptive testing (CAT) systems
based on the graded response model. Simulated
data were used to investigate the effects of systematic
manipulation of various aspects of the CAT procedures
for the model. The effects of three major variables
were examined: item pool size, the stepsize used along
the trait continuum until maximum likelihood estimation
could be calculated, and the stopping rule employed.
The findings suggest three guidelines for
graded response CAT procedures: (1) item pools with
as few as 30 items may be adequate for CAT; (2) the
variable-stepsize method is more useful than the fixed-stepsize
methods; and (3) the minimum-standard-error
stopping rule will yield fewer cases of nonconvergence,
administer fewer items, and produce higher correlations
of CAT θ estimates with full-scale estimates
and the known θs than the minimum-information stopping
rule. The implications of these findings for psychological
assessment are discussed. Index terms:
computerized adaptive testing, graded response model,
item response theory, polychotomous scoring.
Dodd, Barbara G, Koch, William R & de Ayala, Ralph J. (1989). Operational characteristics of adaptive testing procedures using the graded response model. Applied Psychological Measurement, 13, 129-143. doi:10.1177/014662168901300202
Dodd, Barbara G.; Koch, William R.; De Ayala, Ralph J..
Operational characteristics of adaptive testing procedures using the graded response mode.
Retrieved from the University of Minnesota Digital Conservancy,
Content distributed via the University of Minnesota's Digital Conservancy may be subject to additional license and use restrictions applied by the depositor.