I__. - International Military Testing Association

Single-Criterion Predictor Composite
GPA,
GPA,
Table 2
Cross-Validity Coefficients for Single-Criterion and QI-89 Composites
GPA
-
Criteria NSG TECH
.289 .122 .237 .138,
.304 -.oo I .228 ---
APT, .219 .137 .230 .I08
Aflb .220 .073 .193 ---
NSG, .220 .I18 .291 .12l,
NSG, .227 .009 .286 ---
TECH, .102 .036 .137 .430,
TECH, .I23 .056 .063 ---
______________-__--_----------------- ________________________________________--------------------------------------------------------------
QI-89. .282 .I26 .246 .131,
QI-89, 296 .Oll .238 ---
a as a subscript denotes rhe 1983-1986 hold-out sample @ = 2,305).
b as a subscript denotes the 1987 hold-out sample (I’J = 652).
c as a subscript dcnotcs Lhc 1983-1986 rcduccd hold-out sample @ = 1,313) wilh a valid TECH score.
The cocfficicnts oblaincd on Ihe second cross-validation sample arc shown directly under the bold-faccd
cross-validilics. Across all four single-criterion composites, the cross-validilics obtained on the 1987 sample varied
litllc from l.hosc ob@ined on the 1983-1986 sample when GPA and NSG were predicted. All of the composiWs
prcdictcd GPA slightly bcWr in the 1987 sample and NSG slightly bcUer in the 1983-1986 sample. Somewhat
larger differe.nces wcrc found when predicting APT, The GPA, APT, and NSG composites predicted APT bcltcr
in the 1983-1986 sample than in tie 1987 sample. The cross-validities for Ihe two samples were both near .OO
when the’ TECH-derived composite was used to predict APT. Inspection of the correlations between APT and
several highly-weighted predictors (i.e., HSR, SATM, and SATV) rcvealcd that diffcrcnccs in zero-order validities
for the two samples appcarcd to account for the subscqucnt diffcrcnces in predictive abilily for lhcsc composites.
QI-89. The bottom portion of Table 2 contains cross-validity coefficients for QI-89. In gcncral, the crossvalidity
coefricicnts obtained with Ihc QI-89 showed little shrinkage from those obtained when each singlccriterion
predictor composile was used to predict itself. The one exception occurred when TECH was the.
criterion. This finding is logical because CNET assigned a relatively small importance rating to TECH when it
was combined with the other three criteria. Although the QI-89 was only marginally useful for prcdicling APT
and TECH, it retained a moderate level of predictive ability when used to predict GPA and NSG.
Predicting Technical Maiors
As shown in Figure 1, Lhosc midshipmen in the upper 20% on the ES scale were more than twice as likely
to choose technical majors than those in Ihe lower 20%. To use the table, an individual’s ES score is locntccl
in tic table, and Lhc likelihood of that individual sclccling a technical final major can bc determined. An adjunct.
table for estimating ES was used (rather than incorporating ES into the optimally wcightcd selection composilc)
so as lo avoid eliminating applicants with outstanding crcdcntials who might not rcccive NROTC scholarships if
their intcrcsls tcndcd toward non-technical fields of study.
Conclusions
1. Although ES is dcrivcd from an instrument (i.c., Strong-Campbell Interest Inventory) that is susccptiblc
10 distortion, results showed that ES can significantly incrcasc the proportion of technical majors.
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