Observe that the items are clearly classified into the two ends of a contrast factor. Table 23.3 shows them to be stratified into "Against Drugs" and "For Drugs" items.
TABLE 23.2 Recreational Drug Survey drugs.out Apr 12 15:18 1999
INPUT: 39 PERSONS, 20 ITEMS ANALYZED: 39 PERSONS, 20 ITEMS, 5 CATS v2.91
--------------------------------------------------------------------------------
PRINCIPAL COMPONENTS (STANDARDIZED RESIDUAL) FACTOR PLOT
Factor 1 explains 6.21 of 20 variance units
-2 -1 0 1 2
++---------------+---------------+---------------+---------------++
| | A |
| | |
.8 + | +
| | |
| | |
| | B |
| | |
.7 + | +
| | |
| | C |
.6 + | +
| | D |
| | F E |
F .5 + | +
A | | G |
C | | |
T .4 + | +
O | |H |
R .3 + I | +
| | |
1 .2 + | J +
| | |
L .1 + | +
O | | |
A .0 +--------------------------------|--------------------------------+
D | | |
I -.1 + | +
N | | |
G -.2 + | +
| | |
-.3 + | +
| j | |
-.4 + | +
| | i |
| | |
-.5 + g h | +
| f| |
| | |
-.6 + ed | +
| c | |
| b | |
-.7 + | +
| a | |
++---------------+---------------+---------------+---------------++
-2 -1 0 1 2
ITEM MEASURE
TABLE 23.3 Recreational Drug Survey drugs.out Apr 12 15:18 1999
INPUT: 39 PERSONS, 20 ITEMS ANALYZED: 39 PERSONS, 20 ITEMS, 5 CATS v2.91
--------------------------------------------------------------------------------
FACTOR 1 FROM PRINCIPAL COMPONENT ANALYSIS OF
STANDARDIZED RESIDUAL CORRELATIONS FOR ITEMS (SORTED BY LOADING)
FACTOR 1 EXPLAINS 6.21 OF 20 VARIANCE UNITS
+---------------------------------------------------------+
| | | INFIT OUTFIT| ENTRY |
|FACTOR|LOADING|MEASURE MNSQ MNSQ |NUMBER ITEM |
|------+-------+-------------------+----------------------|
| 1 | .83 | .35 .90 .87 |A 20 A:dope |
| 1 | .73 | .67 1.61 1.75 |B 5 A:not use |
| 1 | .63 | .24 1.05 1.04 |C 4 A:unnatural |
| 1 | .58 | .63 .61 .60 |D 14 A:care-givers |
| 1 | .54 | .69 .93 .95 |E 6 A:psycho |
| 1 | .54 | .43 .82 .84 |F 17 A:stupid |
| 1 | .48 | 1.94 .63 .64 |G 19 A:side-effects |
| 1 | .33 | .07 .95 .93 |H 2 A:dangerous |
| 1 | .31 | -.19 1.37 1.40 |I 11 A:no-aspirin |
| 1 | .18 | 1.08 .59 .61 |J 3 A:regret |
| |-------+-------------------+----------------------|
| 1 | -.71 | -.93 1.24 1.26 |a 12 F:relationship |
| 1 | -.66 | -.31 1.06 1.07 |b 7 F:trip |
| 1 | -.64 | -.90 1.60 1.47 |c 10 F:high |
| 1 | -.62 | -.93 .81 .79 |d 8 F:stoned |
| 1 | -.59 | -1.00 1.02 1.19 |e 13 F:drug-scene |
| 1 | -.55 | -.04 .96 .95 |f 15 F:experience |
| 1 | -.50 | -.74 .66 .79 |g 16 F:fun |
| 1 | -.50 | -.25 1.27 1.22 |h 1 F:legal |
| 1 | -.44 | .26 .71 .71 |i 18 F:less-alcohol |
| 1 | -.35 | -1.08 .97 .94 |j 9 F:calm |
+---------------------------------------------------------+
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