Table 20.1 Complete score-to-measure table on test of all items
Table 20.2 Person score and measure distribution
Table 20.3 Complete score-to-calibration table for tests based on whole sample
This Table, which must be selected explicitly with TFILE=, or as a subtable with "Request Subtable" on the "Output Tables" menu, shows an estimated item calibration for all possible rates of success by persons, i.e., the item measure corresponding to every observable proportion-correct-value or item marginal raw score for the entire sample.
Output Tables
Request Subtables
20.3
OK
or enter into your control file:
TFILE=*
20.3
*
TABLE OF ITEM MEASURES ON COMPLETE NON-EXTREME SAMPLE FOR TAP LIKE 4 1-3-4
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| SCORE MEASURE S.E. | SCORE MEASURE S.E. | SCORE MEASURE S.E. |
|------------------------+------------------------+------------------------|
| 0 6.17E 1.87 | 12 .81 .45 | 24 -1.58 .48 |
| 1 4.84 1.08 | 13 .61 .44 | 25 -1.82 .50 |
| 2 3.98 .82 | 14 .41 .44 | 26 -2.08 .52 |
| 3 3.40 .70 | 15 .22 .44 | 27 -2.36 .54 |
| 4 2.96 .64 | 16 .03 .43 | 28 -2.67 .57 |
| 5 2.58 .59 | 17 -.16 .43 | 29 -3.01 .60 |
| 6 2.26 .55 | 18 -.34 .43 | 30 -3.40 .64 |
| 7 1.97 .53 | 19 -.53 .44 | 31 -3.85 .71 |
| 8 1.71 .50 | 20 -.73 .44 | 32 -4.43 .82 |
| 9 1.46 .49 | 21 -.93 .45 | 33 -5.29 1.08 |
| 10 1.23 .47 | 22 -1.14 .46 | 34 -6.61E 1.87 |
| 11 1.01 .46 | 23 -1.35 .47 | |
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SCORE raw score on this item of a complete sample containing all calibrated persons. Table 20.3 shows the score-to-measure table for items with complete data. For items with missing data, this table does not apply. TOTALSCORE=Yes includes extreme persons
TOTALSCORE=No excludes extreme persons (if any).
MEASURE measure corresponding to score (user-scaled with UIMEAN=, USCALE=).
S.E. standard error of the measure.
The statistical information in an item estimate for the entire sample is (USCALE/S.E.)²
The real difficulty of an item is its difficulty relative to ...
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the average difficulty of all the items
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This is the Winsteps default
UIMEAN= 0
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the average ability of all the persons
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Specify:
UPMEAN= 0
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a person who scores 50% on all the items in the test
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a) Run a standard analysis
b) Output Table 20
c) In Table 20.1, look for the measure corresponding to 50% success on the test
d) Specify
UIMEAN = - (corresponding to 50% success on the test)
e) rerun the analysis
f) look at Table 20.1, 50% success on the test should be "0".
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an item on which 50% of all the persons succeed
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a) run a standard analysis
b) Menu: Output Tables
c) Click on first entry "Request Subtables"
20.3
Click on OK
c) In Table 20.3, look for the measure corresponding to 50% success by the sample
d) Specify
UIMEAN = - (corresponding to 50% success by the sample)
e) rerun the analysis
f) look again at Table 20.3, 50% success by the sample should be "0".
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