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Data Description

One English test form from a national standardized examination
administered in 1999 was examined using Q3 index. The test consists of
5 passages and there are 15 items associated with each passage. The
number of examinee who has taken the test is 2551. Since, items are
nested in particular passage in the test, we cannot be certain that
local independence assumption is held for this data. So the check-up
procedure is needed such as calculating Q3 index. IRT item
parameters, , , and , and the examinee parameter,
for 3-PL model of test data were estimated using computer
software from [33]. Once the item parameters and the examinee
parameter are estimated,
can be
estimated using equation 6.6. Then Q3 statistic can be calculated.
Thus, we have a
matrix for the item parameters, ,
, and , called `PAR`, a
matrix for the
examinee parameter,
, called `THT`, and a
matrix for the answers of each student, called `RAW`.

Bryan Carpenter
2004-06-09