I__. - International Military Testing Association

Table 3
Proportion of Criterion Variance (R2) Accounted for by
Significant Predictors (Median Values Across MOS)
Stage (1) (W Pa) (2b) (3b)
Predictors Retained ASV ASV+Sp ASV ASV+P/M
Predictors Entered ASV SP P/M P/M SP
Written Tests: .59 .64 65 .61 .65
Hands-On Tests: .29 .33 133 .31 33
General Soldiering: .47 .51 53 .50 :53 .
Core Technical: .44 .49 :50 .48 51
Skill Qualification: .53 .54 .55 -54 :55
analysis. A comparison of column 1 with columns 3a and 3b
indicates that spatial and perceptual-psychomotor test scores
substantially improved the prediction of Written Test scores,
General Soldiering Proficiency, and Core Technical Proficiency.
Increases in R*s for Hands-On Tests and the Skill Qualification
Test Score were more modest.
Regarding the relative usefulness of spatial vs. perceptualpsychomotor
tests for incrementing the prediction of the
criteria, columns 2a and 2b of Table 3 show median incremental
R2s (across MOS) of spatial vs perceptual-psychomotor predictors
at Stage 2. Spatial tests were slightly better than perceptualpsychomotor
scores for improving the prediction of the criteria.
The third research question concerns the validities and
incremental validities of individual Project A tests. Table 4
lists the three best spatial, perceptual, and psychomotor tests,
in terms of frequency and magnitude of significant effects. For
the tests of spatial ability, Assembling Objects, Figural
Reasoning, and Map were superior incremental predictors. Among
the perceptual scores, Target Identification (% correct), Short
Term Memory (% correct), and Number Memory (response time) were
especially useful as incremental predictors. For the psychomotor
scores, l- and a-Hand Tracking (accuracy), and Target Shoot
(time-to-fire) were the best.
Discussion
In these analyses Project A test scores substantially
improved the prediction of the criteria. The results for Total
Score .on Written Tests and General Soldiering Proficiency support
the wide generalizability of Project A incremental validity.
Specifically, the first measure may involve highly different
content across MOS, while the second measures a set of more
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