This study empirically investigated the validity
and utility of the stratified adaptive computerized
testing model (stradaptive) developed by Weiss
(1973). The model presents a tailored testing
strategy based upon Binet IQ measurement theory
and Lord’s (1972) modern test theory. Nationally
normed School and College Ability Test Verbal
analogy items (SCAT-V) were used to construct an
item pool. Item difficulty and discrimination indices
were re-scaled to normal ogive parameters on
244 items. One hundred and two freshmen volunteers
at Florida State University were randomly assigned
to stradaptive or conventional test groups.
Both groups were tested via cathode-ray-tube (CRT)
terminals coupled to a Control Data Corporation
6500 computer. The conventional subjects took. a
SCAT-V test essentially as published, while the
stradaptive group took individually tailored tests
using the same item pool. Results showed significantly
higher reliability for the stradaptive
group, and equivalent validity indices between stradaptive
and conventional groups. Three stradaptive
testing strategies averaged 19.2, 26.5, and 31.5
items per subject as compared with 48.4 items per
conventional subject. A 50% reduction from conventional
test length produced equal precision of
measurement for stradaptive subjects. Item latency
comparisons showed that those in the stradaptive
group required significantly longer per item (about
11%) than conventional group members. It is
recommended that testing time rather than number
of items be used as a dependent variable in future
adaptive testing research.
Waters, Brian K. (1977). An empirical investigation of the stratified adaptive computerized testing model. Applied Psychological Measurement, 1, 141-152
Waters, Brian K..
An Empirical Investigation of the Stratified Adaptive Computerized Testing Model.
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.