Table 31.5 Within-class fit report (item class within person).
Table 31.6 Within-class fit report (person class within item)
DIF class specification is: DIF=@GENDER
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| TAP OBSERVATIONS BASELINE DPF DPF W-INFIT W-OUTFIT KID |
| CLASS COUNT AVERAGE EXPECT MEASURE SIZE S.E. MNSQ ZSTD MNSQ ZSTD Number Name |
|----------------------------------------------------------------------------------------------------|
| 1 11 .18 .23 -2.94 -.60 1.05 .71 -.53 .25 -.31 1 Adam M|
For a general description, see Table 31.2
The DPF effects are shown ordered by CLASS within person (row of the data matrix).
TAP CLASS identifies the CLASS of items. KID is specified with ITEM=, e.g., the first CLASS is "1-"
OBSERVATIONS are what are seen in the data
COUNT is the number of observations of the classification used for DPF estimation, e.g., 11 "1-" items responses were made by person 1.
AVERAGE is the average observation on the classification, e.g., 0.18 is the average score class "1-' items by person 1.
COUNT * AVERAGE = total score of person on the item class.
BASELINE is the prediction without DPF
EXPECT is the expected value of the average observation when there is no DPF, e.g., 0.92 is the expected average for person 1 on item class "1-" without DPF.
MEASURE is the what the overall ABILITY measure would be without DPF, e.g., -2.94 is the overall person ability of person 1 as reported in Table 18.
DPF SIZE is the size of the DPF
DPF S.E. is the S.E. of the DPF size
W-INFIT is the Within-Group infit statistic for the item CLASS on the person.
W-OUTFIT is the Within-Group outfit statistic for the item CLASS on the person.
MNSQ is the mean-square statistic (chi-square divided by its degrees of freedom).
ZSTD is the mean-square statistic expressed as a z-score (unit normal deviate).
