3. Drug Survey: Item Fit

Observe that the item misfit statistics do not classify the items by their for-against implications.

The score (point-measure) correlation suggests that items 5 (type A: - against drugs) and 12 (type F: - for drugs) both be reversed coded. This would further confuse understanding the variable.

TABLE 10.1 Recreational Drug Survey                 drugs.out Apr 12 15:18 1999
INPUT: 39 PERSONS, 20 ITEMS  ANALYZED: 39 PERSONS, 20 ITEMS, 5 CATS        v2.91
--------------------------------------------------------------------------------

         ITEMS STATISTICS:  MISFIT ORDER

+--------------------------------------------------------------------------------+
|ENTRY    RAW                        |   INFIT  |  OUTFIT  |SCORE|               |
|NUMBER  SCORE  COUNT  MEASURE  ERROR|MNSQ  ZSTD|MNSQ  ZSTD|CORR.| ITEMS         |
|------------------------------------+----------+----------+-----+---------------|
|     5     87     39     .67     .15|1.61   2.5|1.75   2.8|A-.01| A:not use     |
|    10    162     39    -.90     .18|1.60   1.8|1.47   1.4|B .26| F:high        |
|    11    133     39    -.19     .14|1.37   1.9|1.40   1.9|C .31| A:no-aspirin  |
|     1    136     39    -.25     .14|1.27   1.4|1.22   1.0|D .46| F:legal       |
|    12    163     39    -.93     .19|1.24    .8|1.26    .8|E-.03| F:relationship|
|    13    165     39   -1.00     .19|1.02    .1|1.19    .6|F .02| F:drug-scene  |
|     7    139     39    -.31     .14|1.06    .3|1.07    .3|G .38| F:trip        |
|     4    109     39     .24     .13|1.05    .3|1.04    .3|H .30| A:unnatural   |
|     9    167     39   -1.08     .20| .97   -.1| .94   -.2|I .14| F:calm        |
|    15    125     39    -.04     .13| .96   -.2| .95   -.3|J .45| F:experience  |
|     6     86     39     .69     .15| .93   -.4| .95   -.2|j .28| A:psycho      |
|     2    116     38     .07     .14| .95   -.3| .93   -.4|i .26| A:dangerous   |
|    20    103     39     .35     .14| .90   -.6| .87   -.8|h .48| A:dope        |
|    17     99     39     .43     .14| .82  -1.1| .84   -.9|g .34| A:stupid      |
|     8    163     39    -.93     .19| .81   -.7| .79   -.8|f .17| F:stoned      |
|    16    157     39    -.74     .17| .66  -1.5| .79   -.8|e .21| F:fun         |
|    18    108     39     .26     .13| .71  -2.0| .71  -2.0|d .17| F:less-alcohol|
|    19     53     39    1.94     .28| .63  -1.1| .64  -1.1|c .33| A:side-effects|
|    14     89     39     .63     .15| .61  -2.3| .60  -2.3|b .37| A:care-givers |
|     3     71     39    1.08     .18| .59  -1.7| .61  -1.6|a .24| A:regret      |
|------------------------------------+----------+----------+-----+---------------|
| MEAN    122.    39.     .00     .16| .99   -.2|1.00   -.1|     |               |
| S.D.     34.     0.     .78     .03| .30   1.3| .30   1.3|     |               |
+--------------------------------------------------------------------------------+

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