had significantly lower mean scores than the
Navy sample and the Marine sample was superior
to both the FAA and Naval groups. With one
exception, all Marines possessed MSC scores of
110 and higher. The average Marine MSC score
was 127.7. Even though more than 100 of the
Navy trainees had scores of 109 or less, their
average was 1194. Both the Marine MSC score
and the Navy MSC index correlated significantly
with each of the experimentally-derived compo-
site measures. The latter were very highly inter-
correlated. Finally, the CSC-ATC Test. scores,
which were available for one of the two samples
of FAA trainees, correlated 81 with the Com-
mercial 4-Test Composite scores. These relation-
ships tend partially to explain the consistency
with which the Marines were found to be the
superior group. In brief, the Marines in this

study were selected from exceptionally high apti-
tude groups, the Navy trainees were selected
from mid-range levels, and the FAA subjects,
who were required to meet no aptitude standards,
tended to represent much lower levels.

It is of interest to the FAA that: both the
Navy and Marine Corps trainees of the Glynco
ATC School represent rather select groups in-
sofar as aptitudes are concerned. At some future
date, many of these men will apply for FAA
employment. During the interim they will have
gained valuable military air traffic control ex-
perience. When they do apply, a far greater
percentage of them should be able to qualify on
the FAA-CSC-ATC Screening Test than the 25
to 35 per cent of the applicant population of
recent years.

REFERENCES

Coss, Barr B.: Problems in Air Traffic Management :
V. Identification and Potential of Aptitude Test
Measures for Selection of Tower Air Traffic Controller
Trainees. J. Aerospace Medicine, 35, 1019-1027, 1964.
Also published as: Civil Aeromedical Institute Report
AM 65-19, FAA, Oklahoma City, Oklahoma, 1965,

2. Coss, Bart B.: Problems in Air Traffic Management :
Il, Prediction of Success in Air Traffic Controller
School. J. Aerospace Medicine, 33, 702-718, 1962.
Also published as: Civil Aeromedical Institute Report
62-2, FAA, Oklahoma City, Oklahoma, 1962.

18

3. Tarves, D. K.: Problems in Air Traffic Management :
I, Longitudinal Prediction of Effectiveness of Air
‘Traffic Controllers, J. Aerospace Medicine, 32, 1112-
1120, 1964. Also published as: Civil Aeromedical
Institute Report 61-1, FAA, Oklahoma City, Okla-
homa, 1961.

. Terres, D. K., and Coss, Barr B.: Age, Aptitude, and
Experience as Predictors of Performance of Air Traffie
Controllers. Unnumbered Report, Civil Aeromedical
Institute, FAA, Oklahoma City, Oklahoma, 1964,


_ ——— _
2200
---P 98
2000
o--P 90
1800 oo-P 75
o7oMedian
1600 4
---P 25
1400
---P 10
1200 4
1000 ---P 02
8004
6004
Sample @ 1 2 3a 3b 3 Tot 4a 4b 4 Tot
N 2120 (183 435° 214 649 207. 103-310
Type FAA FAA NAVY MAR N+M NAVY MAR = N+M

Ficure 2, Relative Range and Distribution of Commercial 4-Test Composite Scores for FAA, Navy,

and

Marine Corps Trainees.

trainees of Samples 1 and 2 tend to have lower
scores than the Navy students who comprise sub-
samples 3a and 4a and that the Marines generally
have the highest aptitude scores, All differences
between the means of the combined FAA samples,
combined Navy samples and combined Marine
samples were found to be statistically significant.

12

Comparison of FAA, Navy and Marine Ss in
Terms of Estimated CSC Test Scores. The 183
FAA-ATC subjects designated as Sample 2 rep-
resent the only group in this study for whom
scores were available on both the complete CSC-
ATC-Aptitude-Screening-and-Selection Battery
and any portion of the commercially-published


Tante I. Designation of Aptitude Test Scores Available For each Sample of The Study

Sample 1

FAA
N,=212

Sample 4
MILITARY
Ne=310

Sample 3
MILITARY
Np=649

Sample 2
FAA
=183

N,
Np=193 Ne=17 Npe13 Ne=40 Np=581 Ne=64 Np=259 N¢=38

COMMERCIAL TESTS
DAT Space Relations
DAT Numerical Ability
DAT Abstract Reasoning
CTMM Analogies
CIMM Inference
CTMM N. Q. Coins
CTMM N. Q. Arithmetic

De D6 be DS Bd Dd OS

CIVIL
csc
csc
csc
csc
csc
csc

SERVICE COMMISSION TESTS
51-Spatial Patterns
24-Comput ations
157-Abstract Reasoning
157-Letter Sequence
135-Oral Directions
540-ATP I+II

TYPES OF COMPOSITE SCORES DERIVED
Commercial 7-test Composite x
Commercial 4-test Composite x
New 4-test Commercial Composite
CsC_6-test Composite

6 Pe DS Pe

De De Dd Dd PE DE DS
D6 Dd PE PS De PS DS

Dd PS Pe dd be Oe

x

Dd be be
> be be

x

2 of the present study) included scores on four
of the seven commercial tests and the complete
CSC-ATC-Aptitude-Screening-Test. The four
commercial instruments which were administered
to Sample 2 were the DAT subtests of Space
Relations, Numerical Ability and Abstract Rea-
soning and the CTMM subtest Analogies. The
six subscores of the CSC-ATC Test relate to the
subtests of Spatial Patterns, Computations, Ab-
stract Reasoning, Letter Sequence, Following
Oral Directions, and Air Traffic Problems.

Military - Screening - and - Classification - Test
Scores. The Navy and the Marine Corps both
employ MSC procedures which were originally
designed to yield a mean of 100 for a military
population. However, the procedures are dit-
ferent. The Navy MSC index, known as the
“GCT+ARI,” is based on the General Classifi-
cation Test and a test of Arithmetical Reasoning.
The Marine index, “4 (AR+VE+PA),” repre-
sents an average of performance scores on the
tests of Arithmetical Reasoning, Verbal Ability,
and Perceptual Ability. According to Glynco
officials, an index of 110 is. a recommended stand-
ard for the selection of both Navy and Marine

ATC trainees. Findings in this study indicated
that the Marines adhered to this policy while the
Navy made 104 exceptions in selecting 642
trainees.

Criteria. The two criterion variables included
in the present study were “Overall Training
Course Grade Average” and “Pass-Fail Status.”
These comprehensive performance indices repre-
sented the only measures which were similar and
directly comparable for the FAA and Glynco
trainees. .

Factor Weights for Derivation of Composite
Aptitude Measures. Composite aptitude measures
for all Ss were derived through application of
sets of factor weights developed previously from
performance data for several hundred FAA-
ATC trainees. The FAA-ATC samples used
here represent only a minor portion of the pre-
vious sample. The factor weight for each test
was the inverse of the standard deviation of
scores (ie., 1/SD) obtained for the larger group.
The omission of decimals to avoid fractional
values had resulted in a two-digit weight for
each variable. (The application of weights so
developed is essentially equivalent to the equal



not shown, the correlation between the two was
-64 for the Naval trainees and 46 for the Ma-
tines. The estimated Standard Error for the
CSC score was 17.5; the Probable Error was
11.8.) The bar graphs pertaining to the separate
and combined subsamples of both Navy and Ma-
rine Corps trainees indicate that the probabilities
of attaining a qualifying score of 210 on the
CSC Test range from about 72 to 80 per cent
for those subjects having MSC scores of 125 or
higher. Data for the various groups reflect a
progressive decline in these probabilities from
the high to the lower MSC-score-range cate-
gories. For example, 106 of the 640 Navy
trainees of the combined subsamples 3a and 4a
possessed MSC scores of 109 and less. Only
11.3 per cent of the estimated CSC scores for
these 106 individuals are within the qualifying
range of 210 and better, 21.7 per cent are within
the nonqualifying range of 190 to 209, and 67
per cent are lower than the FAA’s former selec-
tion standard of 190. With the exception of one
case, all Marines included in this study had MSC
scores of 110 or higher. One hundred eighty of
these 261 Marines had an MSC score of 125 or
better. Over 78 per cent of the CSC scores pre-
dicted for this elite subgroup are above 209. In
contrast, nearly 60 per cent of the 81 Marines
having MSC scores of 110 to 124 would probably
not qualify on the CSC Test.

Actual or Estimated OSC Test Performance
Versus Chronological Age. Previous research*
based on a group of 306 FAA-TATC trainees,
including the 183 subjects designated as Sample
2 in this study, revealed a negative correlation
of .33 between CSC Test Score and Chronological
Age. The mean CSC score for trainees over age
35 was significantly lower than for the younger
groups. Similar results for the 395 FAA trainees
of combined Samples 1 and 2 have emerged in
the present study. The correlation between age
and CSC score is —.25. Fifty-six of the 395
FAA Ss were 36 years of age or older when
tested. The mean OSC score for this group is
170.4, The mean for those aged 35 and less is
194.1. The difference between the two groups is
not as great as found in previous studies but it is
statistically significant. (It should be noted that
these results and those in Table V are based on
analyses involving no distinction between pre-
dicted CSC Test scores and actual performance.)

16

Taste V. Means of Actual or Predicted CSC-
ATC Test Scores by Age Group for FAA,
Navy, and Marine Corps ATC-Trainee

Samples.
Sample 1+2 Sample Jatia Sample 3b+4b
Chronological
Age HM N nt N x
45&> 1 217.00
43 - 4a 9 149.50
Gl - 42 120 (149.71
39 - 40 16 184.34
37-38 15 173.33,
35 = 36 6 210.75 1 164.50
33 - 34 15 173.00
31-32 21 195.69 3 187.83
29 - 30 40 191.50 1 254.50
27 - 28 360 -191.51 7 187.36
25 - 26 73° (195.84 WW 217.36 3) 181.17
23> 2% 123 196.3762 204.34 12,213.67
21 - 22 28 (195.21 158 205.83 46 218.41
19 - 20 331 202.26 © 198 222.23
17 - 18 65 204.65 | 4H 213.82
Total —395 190.75 _642_203.71 _303_219.68

Table V presents the means of the (actual
and/or predicted) OSC Test scores, by age group,
for the FAA, Navy, and Marine Corps trainees.
In comparing means of CSC scores for subjects
in successive two-year age intervals, considerable
variability. is evident within each array. Yet,
the data for the FAA trainees follow a trend
which reflects the previously-established differ-
ences between performance levels of the older
and younger trainees. There is also some degree
of correspondence between age and level of pre-
dicted CSC Test score for the Navy subjects of
combined Subsamples 8a and 4a. Most of these
trainees are relatively young; only 12 are over
age 26. One of the 12, in the 35-to-36 year
bracket, has an estimated score of 164.5. Ten of
the 12, in various age brackets, were found to
have an average score of approximately 187,
The overall average for these 12 older individuals
is 191.1, compared to about 204 for the 630
younger Navy trainees. The difference, however,
is not statistically significant. All of the Ma-
rines are younger than 27 and no association be-
tween level of estimated CSC Test performance
and age level was found for this group.


Tastx IV. Intercorrelations and Validities* of Composite Aptitude Measures for Navy

and Marine Trainee

roups

Sample 3at4a 4-test New 4- MSC Course Pass-
Comp, test Comp. Test Grade Fail

Navy Mean N N N N N

s.D. r r r r Tpb
Commercial 2859.2 642 642 640 621 552-77
7-test Composite 442.5 +92 93 71 41 +26
Commercial 1583.2 642 640 621 552-77
4-test Composite 284.4 OL 64 38 223
New 4-test 296.9 640 621 552-77
Comm. Composite 44.7 64 Al +26
MSC Test 119.4 619 550-77
GCT+ARI 10.1 44 28
Course Grade 79.3 551-70

8.3 +64
Sample 3b+4b
Marine Mean N N N N N

S.D. r r r r lpb
Commercial 3163.7 317 317 262 312 288-25
7-test Composite 382.1 +90 90 51 41 23
Commercial 1730.0 317 262 312 288-25
4-test Composite 245.7 288 46 Al +21
New 4-test 325.5 262 312 288-25
Comm. Composite 38.0 +46 Al 22
MSC Test 127.7 258 235-24
1/3(AR+VE+PA) 6.6 221 12
Course Grade 80.7 288-24

6.8 +52

*All intercorrelations and validities are significant at the .01 level or better except the Marine
Corps MSC Test Score palidity coefficient of .12, which is significant at the .05 level.

the combined Marine groups. Validities of the
three composites are, as previously discussed,
virtually equivalent for the Navy and Marine
groups. In other words, the predictive useful-
ness of either of the two four-test composites
approximates that of the complete seven-test
battery. However, comparison of the validities
of the MSC test scores with those obtained for

each of the experimentally-derived composites
leads to some rather conflicting findings. For
the combined Navy groups 8a and 4a, the validi-
ties of each composite are slightly exceeded by
those of the Navy MSC score. For the combined
Marine groups 3b and 4b however, the validities
of the composites are, in every instance, appreci-
ably higher than those of the Marine MSC score.


for all aptitude measures for all samples are
shown, only those relating to Samples 1, 2 and 3
were determined in the initial stages of the study.
Sample 4 was used, in a restricted sense, for
cross-validation purposes.

Empirical Validities of the Commercially-
Published Tests. The empirical validities of the
commercially-published instruments appear in
the upper portion of Table II. A comparison
of the data for the first three samples reveals
that the validity coefficients for some tests vary
in magnitude from sample to sample. Yet, with
the exception of CTMM Analogies for Sample 1,
all test validities established with both FAA
samples and the Glynco subjects of Sample 3
proved to be statistically significant. The va-
lidities obtained for Sample 1 are generally lower
than those derived for Samples 2 and 3, and in
most instances, are considerably lower than those
previously established with more comprehensive
groups of FAA trainees, In contrast, the test
coefficients obtained for Sample 2 are substantial
and within an expected range. With the excep-
tion of CTMM Analogies, this is also true for
most of the test validities obtained with the
Glynco trainees of Sample 3. Further compari-
son of the corresponding data across the different
samples indicates that each test measure tended
to correlate more highly with Course Grade than
with Pass-Fail Status. This is not surprising
jnasmuch as the training-course-failure cases
represent only 8.1 per cent of Sample 1, 21.9 per
cent of Sample 2, and 9.9 per cent of Sample 3.
In fact, the failure rates for Samples 1 and 3
are so low that the point-biserial coefficients could
legitimately have been omitted.

Comparison of Empirical Validities of OSC
and Non-CSC Tests for Sample 2. Within the
context of the present study, performance scores
on each of the six subtests of the CSC-ATC
Aptitude Battery were available only for those
FAA subjects designated as Sample 2. The ex-
perimental testing of these former FAA-TATC
trainees had also included the administration of
the three DAT subtests and CTMM Analogies.
Validity data’ for the various aptitude measures
for Sample 2 appear in Table II. Validities of
the CSC subtests range from .23 to .55 for Course
Grade and from .16 to 45 for the Pass-Fail
criterion. All are statistically significant. How-
ever, the validities for each of the four non-CSC
tests are in most instances even better than those

derived for the CSC measures. Though not pre-
sented in any table of this report, intercorrela-
tions of the various test measures were also
computed for this sample. For example, 9 cor-
relation of .72 was obtained between the scores
of the DAT Space Relations Test and CSC Spa-
tial Patterns. Such a correlation lends to the
hypothesis that the similarly-named tests are also
similar in factor content. In this same respect,
DAT Numerical Ability was found to correlate
51 with CSC-Computations and a coefficient of
.48 was obtained between DAT Abstract Reason-
ing and CSC Abstract Reasoning.

Various composite scores, involving different
groups of test measures (and based on the appli-
cation of previously established factor weights
as described in preceding portions of this report)
were derived for the subjects of the respective
samples. Two such global scores were developed
for every FAA subject in Sample 2. One of the
two, involving the three DAT subtests and
CTMM Analogies, is referred to as the “Com-
mercial 4-Test Composite.” The other is the
“CSC 6-Test Composite”. The validities of the
two composites (see Table II) are almost equiv-
alent. With Course Grade as the criterion, the
validity of the Commercial 4-Test Composite is
.52 while that of the CSC composite is 54. The
corresponding validities with the Pass-Fail eri-
terion are .40 and .89. The comparability of the
validity data for the separate and combined sub-
tests, the inter-group correlations for the simi-
larly named but different subtests, and the
correlation of .81 between the two composite
scores of Sample 2 constitute convincing evi-
dence of a high degree of equivalence in the two
batteries. Inasmuch as Samples 1, 3, and 4 were
not administered the CSC battery, this correla-
tion of .81 (not presented in a table) provided
the basis for an equation used in later phases of
the study to estimate CSC-ATC Test perform-
ance from scores attained on the four commercial
tests.

Empirical Validities of “Commercial 7-Test
Composite” and “Commercial 4-Test Composite”
for Samples 1 and 3. The uniform battery of
tests administered to the FAA trainees of Sample
1 and the Glynco trainees of Samples 8 and 4
included all seven commercial instruments but
none of the CSC subtests. Two composite meas-
ures were computed at this stage of the study
for every subject represented in Samples 1 or 3.



weighting or simple addition of test performance
measures rendered in standard score form.) In
the present study, the original two-digit factor
weights were applied to derive two of the three
composite-aptitude measures involving the com-
mercially published instruments. These are re-
ferred to as the “Commercial 7-Test Composite”
and the “Commercial 4-Test Composite.” In
contrast, the “New 4-Test Commercial Compo-
site” and the “CSC 6-Test Composite” are based
on single-digit factor weights. In each of the
latter instances however, the weights represent
a simple and proportionate reduction of the
original set of two-digit weights to single-digit
values. Those pertaining to the CSC tests are

identical to the factor weights prescribed by the
USS. Civil Service Commission.

IIL, Results.

Numerous analyses were accomplished in this
study and the results constitute a large body of
data. The order in which the results are pre-
sented reflects a compromise between the sequence
in which the statistical analyses were undertaken
and the relevance of results across different
analyses to one or more objectives of the study.
For example, the empirical validities of the
various aptitude tests, when used separately and
in combination for prediction of Training Course
Grade and Pass-Fail Status, are presented simul-
taneously in Table II. Even though coefficient

Taste II. Empirical Validities of Aptitude-Test Variables

Sample 1 Sample 2 Sample 3 Sample 4
FAA FAA MILITARY MILITARY
Course Course Course Course
Grade _P-F_ Grade P-F_ Grade _P-F_ Grade _P-F
Ne Np-Né Ne Np-Né Ne ONp-NE_ ON Np-NE
r Tpp r pp r Tpb r Tpp
COMMERCIAL TESTS N=211 193-17 N=183 143-40 N=636 581-64 N=297 259-38
DAT Space Relations +14 20% Uae 37% BTR 1g 25a 212%
DAT Numerical Ability 133%% 19 36m 24K BBR 22% LUO 2 7ee
DAT Abstract Reasoning 40k 138% ATK 32K 29K J Lhe 3G ek 23%%
CIMM Analogies +12 .09 o27%e .25hR 15K 11 08.04
CTMM Inference 227% .25%% 224ee JZ 13% 12k
CTMM N. Q. Coins oS LR 25% 227%e (19%R 413% 09
CIMM N. Q. Arithmetic -38%* 16% 233% 19% 3 Lee 24H
CIVIL SERVICE COMMISSION TESTS N=183 143-40
CSC 51-Spatial Patterns 237*e .27%%
CSC 24-Computations «28%* 116%
CSC 157-Abstract Reasoning 28k .18%
CSC 157-Letter Sequence 7S5** G5ek
CsC 135-Oral Directions o23%e 234%
CSC 540-ATP I+II ALEK .29%%

COMPOSITE SCORES N=211 193-17 N=183 143-40 N=636 581-64 N=297 259-38

Commercial 7-test Composite 239% 3] ek 42ke 26% 3D 26ee
Commercial 4-test Composite 32H 29% SDR LOK 39% 23% LLOKR 25 4k
New 4-test Comm. Composite 41 R 25% DR 27
CSC 6-test Composite SAR 39%

MILITARY (MSC) SCORES

GCT + ARI for Naval Ss N=422 379-51 N=197 171-26

42k 28K ATK L27HK
1/3 (AR+VE+PA) for Marine Ss N=184 173-12 N=74 62-12
.18* 01 227* 18
*p<.05
ep .01


IV. Discussion.

Although most of the Navy and all of the Ma-
rine trainees included in this study were selected
from relatively high MSC score ranges, the re-
sults indicate that further improvement in the
screening and selection of applicants for Glynco
ATC training could be attained by requiring a
score of 110, or possibly 115, on the MSC Test
and through secondary aptitude testing and
screening procedures. A score of 110 on the
MSC Test as a selection requirement would re-
sult in the exclusion of many potential fail and
marginal-pass cases. However, if an MSC score
of 110 constituted the qualification standard, the
three DAT tests of Space Relations, Numerical
Ability and Abstract Reasoning and the CTMM
Inference test (or tests of a highly similar type)
could be used to effectively screen additional
numbers of individuals who would either fail or
only marginally pass the training course. On
the other hand, if an MSC selection score of 115
were chosen, supplementary aptitude testing and
seconding screening procedures would be of only
limited value. However, the feasibility of im-
plementing any new method depends upon many
factors. For example, the ratio of the number
of applicants to the number of trainee positions
to be filled should be a prime determinant of the
specific qualification levels. A determination
would also be in order regarding the extent to
which priority selection of ATC personnel from
high aptitude levels might conflict with demands
for high-aptitude personnel for other crucial
specialty areas.

The finding of insignificant relationships be-
tween chronological age and the experimentally-
derived aptitude measures of the Navy and
Marine Corps trainees is not surprising in view
of the fact that only 12 of the Navy subjects
(and none of the Marines) were over 26 years
old. The mean performance level for the 12
older Navy trainees was admittedly lower than
for the younger group of students but not sig-
nificantly so. However, the age at time of testing
ranged from 21 to 46 for the former FAA-TATC
trainees. The older FAA subjects tended to have
appreciably lower aptitude scores. Differences
between the means of aptitude measures for
dichotomized groups aged “35 and younger”
versus “36 and older” was found to be statistically
significant. This finding is in general agreement
with results obtained in previous research with

17

larger groups of TATC trainees and Center (or
air-route-traffic-control) trainees. Observations
during testing sessions at CAMI indicated that
older examinees generally experience more dit-
ficulty with tests involving perceptual speed,
rapid assimilation and processing of information,
and the retention of instructions pertinent to the
more novel tasks. Older individuals appear to
be less “flexible” and more “persevering” than
their younger colleagues in seeking solutions to
the more difficult problems of many tests. Some
authorities may theorize that recency of educa-
tion and exposure to testing situations is partially
responsible while others will contend that the
older individuals are apt to have lower levels of
motivation. Yet, it remains largely a matter of
speculation as to why the older FAA trainees
tend to havé lower composite aptitude scores
than the younger trainees.

The FAA-ATC trainees included in this study
were recruited during 1961 and 1962 when an
assessment of types and amounts of previous
job-related experience (particularly military
‘ATC work) constituted the primary basis for
selection, Qualification involved no formal assess-
ment of aptitudes. However, this was also a
period during which research was being con-
ducted to establish the degree to which the selec-
tion process might be improved through the use
of aptitude tests. The FAA-ATC trainees in-
cluded in this study were participants in that
research and were administered an extensive and
heterogeneous battery of aptitude tests on an
experimental basis at the time they entered
training. The results obtained in this study indi-
cate that if the CSC-ATC test had been in oper-
ational use, almost 65 per cent of these trainees
would never have been selected. Inasmuch as
the majority of these men were selected on the
basis of their military ATC experience, there
must have been inadequacies in the procedures
by which they were selected and assigned to
military ATC training. Unfortunately, the
existing research records are incomplete regard-
ing the respective military organization in which
each FAA trainee attained his entry-qualifying
experience and no comparative study in this re-
spect has yet been made.

The present study permitted a comparison of
the average performance levels of FAA, Navy,
and Marine Corps trainees on several groups of
aptitude tests. In all instances, the FAA samples



Taste III. Comparative Validities of Aptitude Tests and Composites for FAA, Navy, and Marine

Corps ATC Trainees
Ee
Sample 1 Sample 2 Sample 3a Sample 3b = Sample 4a Sample 4b
PAA FAA NAVY MARINE NAVY MARINE

Course Course Course Course Course Course

ra Grade _P-F Grade _P-F Grade P-F Grade _P-F___Grade__P-F
Ne Np-We Me MprWe Me RprNe Ne MpNe Ne RyNe Ne Np'Ne
rtp rrp OF > FOF a r 9b

COMMERCIAL TESTS W211 193-17 Ne183 143-40 N=423 380-51 N=213 201-13 N=198 172-26 N=99 87-12
DAT Space Relations 14 208% Gljieke 37H GLI BR 26H 412.23 «10 Bee 16
DAT Numerical Ability 233% 19M 36H 24mm THK 23H 30H 10 Glee 27 43h 29%
DAT Abstract Reasoning — .40#* 38h" = JA7#R .32kH 30H 15% 23% .05 sBhik (23K (G2 21H
CIM Analogies +12 .09 L27eR (25% (12k 410k 19H 14k 05-02 +15 .08
CTMM Inference 227 25% sue (22K 413 1008.10 225% 415
CTA N.Q. Coins ASL 2508 129% (22K 113.03 1.05 19.17
CMM N.Q, Arithmetic 138** 116% whi (21 22H 07 33 20K 3S (BBE

CIVIL SERVICE COMM. TESTS Ne183 143-40
CSC 51- Spatial Patterns A378 27h
CSC 24- Computations 28k 16
CSC 157- Abstract Reas. 28K 186
GSC 157- Letter Sequence SSA 45%

CSC 135- Oral Directions 2 23HK 23%
SC 540- ATP I+IT Ahk, 29%

COMPOSITE SCORES Ne211 193-17 N=183 143-40 N=423 380-51 N=213 201-13 N=198 172-26 N=99 87-12
Commercial 7-Test Comp, .39%* .31*t sADkH 28m 35K 1Ge | 37H 23 ABH BDF
Comercial 4-Test Comp. .32%* .29%e 52mm 40H BBR 23h 35%H (15% 38K W23HH SOK 2B
New 4-Test Commerc. Comp. {ALi (27% 133K L1G 39k 26m SL 30K
CSC 6-Test Composite Sate 39%

MILITARY (MSC) TESTS Ne422 379-51 N=184 173-12 N=197 171-26 N=74 62-12
CT + ART h2kk 28 ATi 27H
1/3 (ARHVE+PA) 1g*_.01 27* 418

Fp <.05

p< OL

since later analyses revealed that the majority
of the Marines possessed exceptionally high
MSC scores. The Navy selected its trainees from
a broader range of ability levels. The correla-
tions of .42 and .28 obtained in Sample 3 for the
Navy MSC score versus Course Grade and Pass-
Fail Status and the corresponding coefficients
of .47 and .27 obtained for Sample 4 should also
be considered as possible underestimates of the
true validities of this screening variable. Yet,
despite the presumed restriction-of-range effects,
the obtained, uncorrected validities are substan-
tial and exceed those obtained for any of the
experimental measures.

Differential Validities of Aptitude Measures
for FAA, Navy, and Marine Corps Groups.
Validities of the various aptitude measures were
computed independently for the subgroups of
Navy and Marine trainees of Samples 3 and 4.
These data, together with those previously de-
rived and shown for Samples 1 and 2, are pre-
sented in Table III. It is apparent that the

validities for each of the seven subtests tend to
fluctuate from sample to sample. There is little
evidence that any particular subtest constitutes
a unique or highly superior predictor of training
performance for either the Navy or the Marine
trainees. Also, no composite measure appears to
be consistently more valid for one group than
the others. Validities of the three composites
vary from sample to sample but they are remark-
ably similar for any given sample. With Course
Grade employed as the criterion, they range from
.38 to 42 for Sample 3a (Navy); .87 to .39 for
4a (Navy) ; 38 to .85 for 3b (Marines), and .48 to
.51 for Marine Sample 4b.

Intercorrelations and Validities of Composites
and MSC Score. The intercorrelations and va-
lidity coefficients of the three experimentally-
derived composite aptitude measures and the
MSC test: scores of the Glynco trainees are pre-
sented in Table IV. The intercorrelations of the
three composites range from .91 to .93 for the
combined Navy groups and from .88 to .90 for



AM 68-14

A COMPARATIVE STUDY OF AIR TRAFFIC TRAINEE
APTITUDE-TEST MEASURES INVOLVING NAVY,
MARINE CORPS AND FAA CONTROLLERS

Bart B. Cobb, M.S.

Approved by Released by

é
J. Roserr Diniz, M.D. P. V. Sumdex, M.D.

Cer, Civ, AzROMEDICAL Feperat Arr SurcEON
InstiTUTE

September 1968

Department of Transportation
FEDERAL AVIATION ADMINISTRATION
Office of Aviation Medicine



Relative Screening Potential of MSC Scores
Versus Two Four-Test Composites. The graphs
in Figure 1 illustrate the relative effectiveness
of the Commercial 4-Test Composite, the New
4-Test Commercial Composite, and the two MSC
Scores as predictors of Pass-Fail Status and
ATC Training Course Grades of the Navy and
Marine trainees. For each graph, the aptitude
measures have been arranged with reference to
three score ranges. These groupings are not
arbitrary. A score of 1650 on the Commercial
4-Test. Composite is roughly equivalent to a
minimum qualifying score of 210 on the CSC
FAA-ATC Selection Test and a score of 1450
approximates a CSO-ATC test score of 190,
which represented the FAA’s qualifying standard
during 1962 and 1963. Scores of 1449 and below
thus correspond to CSC-ATC scores of 189 and
less, Similarly, scores of 310 and 280 on the
New 4-Test Commercial Composite are equivalent
to 210 and 190 on the FAA test. The general,
though not rigidly enforced, standard of an MSC.
score of 110 for selection as a Glynco trainee is
reflected in the groupings established for the
MSC score. However, grouping of MSC scores
of 125 and higher to establish a third group was
done on an arbitrary basis.

The first two graphs illustrate the potential
of the Commercial 4-Test Composite to further
improve the screening of candidates: for the
Glynco ATC training course. Data for the com-
bined subsamples 3a and 4a reveal that 280 of
the 628 Navy trainees attained scores of 1650 or
higher. Only 6 per cent of these 280 high-
scoring individuals failed the training course,
17.1 per cent passed with a “marginal” course
grade (of 76 or lower), and the remaining 76.8
per cent passed with a grade of 77 or higher.
The failure rate progresses to about 13 per cent
for those having scores of 1450 to 1649 and te
21.3 per cent for those having relatively low
scores of 1449 and less. The percentages repre-
senting marginal-pass cases increase in a similar
manner, progressing to 24.9 for the intermediate
Score-range group and to 32.2 for subjects having
scores of 1449 or less.

The second graph of Figure 1 refers to the
combined Marine Subsamples 3b and 4b. A
total of 210, over 67 per cent of the 313 Marines,
attained scores of 1650 or higher on the Commer-
cial 4-Test Composite. About 44.6 per cent of
the Navy trainees were represented in this score

10

range. Although the score distribution is quite
different, the percentages representing the fail,
marginal pass, and non-marginal pass cases
within each of the three score-range groupings
are remarkably similar to those obtained with
the combined Navy subsamples. The failure
rate progresses from about 5 per cent for the
upper group to approximately 10 per cent for
the intermediate group and up to 25 per cent
for the group of subjects having scores of 1449
and less. Percentages representing the marginal-
pass cases reflect a progression from 14.8 per
cent in the upper score-range category to over
28 per cent in the lowest.

Even though the results are not graphically
depicted, a similar analysis was undertaken for
the 393 FAA-TATC trainees of combined Sam-
ples 1 and 2. Only 117 trainees were found to
have Commercial 4-Test Composite Scores of
1650 or better, 111 had intermediate scores of
1450 to 1649, and 165 (almost 42 per cent) had
scores of 1449 or less. In contrast, only 29 per
cent of the 628 Navy students and only slightly
more than 10 per cent of the Marines made scores
of 1449 and less, (Differences in aptitude levels
of the groups will be discussed later in this
report.) At this point however, it is more im-
portant to consider the screening potential of the
Commercial 4-Test Composite. Of the 117 FAA
Ss having high scores of 1650 and above, less
than 6 per cent failed the TATC training course,
about 15 per cent passed with marginal grades
(ie, in approximately the lower fourth of the
distribution of passing grades), and almost 78
per cent were in the upper three-fourths of the
combined classes. Almost 10 per cent of the 111
subjects with intermediate scores of 1450 to
1649 failed and about 16 per cent were cate-
gorized as marginal. Of the 165 having scores
of 1449 and lower, 23 per cent failed, 30 per cent
were marginal, and only 47 per cent passed with
good grades. In summary, two-thirds of the 57
failures and over half of the 86 marginal cases
could have been screened from the two FAA
samples by using 1449 as-a minimum qualifying
score. The results would yield a graph highly
comparable to that shown in Figure 1 for the
combined Navy Subsamples 3a and 4a.

The second pair of graphs in Figure 1 illus-
trate the degree to which the New 4-Test Com-
mercial Composite Score can be used to predict
performance in the Glynco training course.


Inasmuch as the majority of the Marines were
known to have been selected from relatively high
MSC score ranges, this finding prompted a fur-
ther statistical analysis to estimate the validity
of each composite with the effect of the MSC
score theoretically held constant. The resulting
partial correlations are not shown but were quite
moderate, For the combined Navy groups, the

Feil
(Failed train-

highest partial correlation was 11, for the “New 4-
Test Commercial Composite.” For the Marines, the
partials ranged from .18 to .20. These results indi-
cate that if the MSC qualification standards re-
main unchanged, the commercially-published tests
involved in any of the three composites would pro-
duce only a moderate degree of improvement in
the screening of Glynco candidates.

Marginal Pa
(Passed with

La

ing course) low grede*) good grede)
Com. 4-Test
Semple Score _NAYY a
1650 & > 76.8% 280
Sebua 1450 - 1649 62.4% 165
1449 & < 46.57% 183
1650 & > 210
Bota 1450 - 1649 63.4% n
1449 & < 66.9% 32
310 & > 257
Jethe 280 - 309 60.6% 170
279 & < 46.8% 201
310 & > 222
3orab 280 - 309 &
279 & < 4b 6 27
Military Test
NAVY (GCT + ARI)
125 & > 80.8% 198
Jato 110 - 124 5.3L 61.1% 326
109 6 < CELA 1.3% 106
___ MARINE (1/3) (AR+VE+PA)
125 & > 11M 9
Boab 110 - 124 Bz LA, 55.7% 9
109 & < 100% 1

Figure 1. Percentages of Navy and Marine Corps ATC Trainees by Score-Range Groupings

on the Commercial 4-Test Composite, New 4-Test Commercial Composite, and Military

(MSC) Test

who Failed, Marginally Passed, or Now-Marginally Passed the Glynco Training Course.

*Marginal Pass S’s are those with training-course grades of 76 or lower; they comprise the approximate lower

fifth of the distribution of grades.



The first. measure, based upon all seven tests, is
referred to as the “Commercial 7-Test Compo-
site.” The second, based on the four commercial
tests which had been administered (along with
the CSC battery) to Sample 2, is referred to as
the “Commercial 4-Test Composite.” This com-
posite is the same as previously described and
computed for Sample 2. The validity coefficients
for both composites appear in the lower portion
of Table II. Validities of the seven-test com-
posite for Course Grade are .39 and .42 for Sam-
ples 1 and 8, respectively. The corresponding
validities of .32 and .39 for the four-test com-
posite compare very favorably with those ob-
tained for the complete seven-test battery. This
is also true for the Pass-Fail validities, which
(for either composite) are lower than those ob-
tained with the Course Grade criterion. Validi-
ties of the two composites for Samples 1 and 3
are, without exception, lower than those obtained
for Sample 2 with the four-test composite.
Nevertheless, all of the validity coefficients are
statistically significant.

Development of “New 4-Test Commercial
Composite” For Maximized Validity. In view
of the frequency of low and questionable validi-
ties for the CTMM Analogies Test, the specific
combination of selected variables for the most
valid composite was determined. Using inter-
correlations and validity coefficients obtained for
Sample 1, a multiple-regression analysis was
undertaken. This analysis identified DAT Space
Relations, DAT Numerical Ability, DAT Ab-
stract Reasoning and CTMM Inference as the
most effective predictor combination. A similar
analysis on the Glynco trainees, Sample 3, indi-
cated the same four measures as the most valid
composite. For both samples, the multiple cor-
relation (“R”, or estimate of maximum possible
validity) of the new four-test composite with
Course Grade was found to be 45. With Pass-
Fail employed as the criterion, an R of .39 was
found for Sample 1 and an R of .31 for Sample
3. The new composite scores, derived through ap-
plication of single-digit factor weights (described
earlier), were computed for Sample 3. These cor-
related 41 with Course Grade and .25 with Pass-
Fail Status. These coefficients of 41 and 25 ap-
proximate the indicated multiple correlations of
.45 and .81 obtained by multiple regression analy-
sis and thus serve to illustrate the appropriate-
ness of the modified set of factor weights.

Validation of Tests and Composite Aptitude
Measures with Sample 4. Complete records,
consisting of performance scores for the entire
group of seven commercial tests, training-course
grades and pass-fail information, were available
for 297 of the 310 Navy and Marine trainees.
Validity coefficients of the separate subtests were
obtained; three composite scores, the “Commer-
cial 7-Test Composite,” the original “Commercial
4-Test. Composite,” and the “New 4-Test Com-
posite,” were derived; and the validities of the
three composite measures were determined. The
validities of the separate and combined test
measures are presented in Table II. The data
indicate that CTMM Analogies has less predic-
tive potential than any other test. With the
exception of Number Quantity-Arithmetic, the
validities of all the CTMM subtests are rather
low. However, the correlations of the three DAT
measures with Course Grade, which range from
25 to 40, are not appreciably different from
those obtained with Sample 3. The validities
of the three composite measures range from .39
to 42 for Course Grade and from .25 to .27 for
pass-fail, Validities of the “New Commercial
4-Test Composite” are only slightly higher than
those obtained for the other two composites.

Comparison of Empirical Validities of All
Oomposites for All Samples. A review of all
validity coeflicients in Table II reveals no ap-
preciable differences between the corresponding
validities of the three composites for any sample.
The validities of each composite are also remark-
ably similar across all samples. All the com-
posite measures correlate about .40 with the
training-course grades of the Glynco subjects,
Samples 3 and 4, yet the data indicate that the
three DAT tests and CTMM Inference constitute
the best predictor composite.

Validities of the Military-Screening-and-Clas-
sification Test Scores. The empirical validities
of the MSC Test scores for Glynco trainees,
Samples 3 and 4, are shown in the lower portion
of Table II. Since the MSC scores were pre-
requisites for trainee selection, it is important to
recognize that these samples are probably quite
restricted in range and that these validity co-
efficients may grossly underestimate the actual
validities. (Each correlation presented is un-
corrected for “restriction of range” effects.)
The validities for the Marine MSC score range
from .27 to .01 but probably have little meaning


battery for experimental study at the Glynco
training facility. The administration and vali-
dation of this battery at Glynco was the major
objective of the present investigation. Other
objectives included: (a) determination of pos-
sible differences between the aptitude levels of
the Navy and Marine Corps trainees; (b) com-
parative evaluation of the experimentally-
deprived aptitude measures versus the military-
screening-and-classification (MSC) scores as
predictors of training-course performance; (c)
determination of the relationship between chron-
ological age and aptitude performance; and (d)
the establishment of projected estimates regard-
ing the proportion of Navy and Marine students
who (considered as potential applicants for
FAA-ATC training) would be able to qualify
on the CSC-ATC Aptitude Screening Battery.
In order to facilitate a more direct comparison
of Navy and Marine ATC trainees with those
of the FAA, the design of the study was extended
to include consideration of data for two groups
of former FAA-ATC trainees.

IL Procedure.

In implementing the study, CAMI assumed
responsibility for providing copies of the test
booklets, the accomplishment of all analyses of
data, and preparation of a report of findings.
Glynco officials were responsible for the experi-
mental administration and scoring of the tests
and the collection of correlative data. Test
scores, military - screening - and - classification
(MSC) test data, chronological ages, and train-
ing-course performance information for over 950
Glynco students were subsequently forwarded to
CAMI for analysis.

Samples. The two groups of FAA-ATC sub-
jects selected for inclusion in the study repre-
sented the class inputs for the Aeronautical
Center’s Basic Terminal-Area-Traffic-Control
(TATC) Training Course during the period
September 1960 through June 1962. Even though
it has since been discontinued (i.e., replaced by a
program in which recruits receive intensified
training and instruction within their facility of
assignment), this former TATC training course
was highly similar to that provided at the Glynéo
NAS. Both groups of FAA-TATC students had
participated in a CAMI experimental aptitude-
assessment program at the time of entry into
training. As will be pointed out later however,

the two groups had not been assessed with the
same battery of aptitude tests.

The data represented in the various phases of
the present investigation pertain to a total of
395 former students of the FAA-TATC Training
Course and 959 Navy and Marine trainees of the
Glynco NAS ATC Training Course. Two hun-
dred and twelve FAA-ATC subjects who entered
training during September 1960 through July
1961, designated as Sample 1, had been assessed
with an aptitude test battery which included the
seven commercially-published tests. The remain-
ing 183 FAA-ATC cases, Sample 2, represent
TATC classes of August 1961 through June 1962,
and had been examined with both the complete
CSC-ATC-Aptitude-Screening Battery (prior to
its operational implementation) and a uniform
set of four of the seven commercial instruments
selected for use at Glynco. All but four of the
963 students who entered the Glynco Course from
March 1966 through February 1967 were admin-
istered the uniform battery of seven commercial
tests on an experimental basis at the time of entry
into training. A group of 649, consisting of 435
Navy trainees and 214 Marines who entered
training during the earlier two-thirds of the
indicated time period, were designated as Sample
8. The remaining 310 Glynco cases, representing
207 Navy and 103 Marine trainees, were assigned
to the fourth sample. In order to compare the
Navy versus Marine students, Samples 3 and 4
were further divided into subgroups designated
as “3a-Navy (N=435),” “3b-Marine (N=214),”
“4a-Navy (N=207),” and “4b-Marine (N=108).”

Aptitude Tests. As “shown in Table 1, the
seven commercially-published aptitude tests con-
stituted a uniform battery used in the assessment
of the FAA subjects of Sample 1 and the Navy
and Marine trainees of Samples 3 and 4. Three
of the seven are subtests of the Psychological
Corporation’s well known Differential Aptitude
Test (DAT), namely “DAT-Space Relations,”
“DAT-Numerical Ability,” and “DAT-Abstract
Reasoning.” The remaining four, which repre-
sent subtests of the California Test Bureau’s
Test of Mental Maturity (CTMM, Advanced
Form A edition), are referred to as “Analogies,”
“Inference,” “Numerical Quantity — Coins”
(which involves the mental manipulation of
varying monetary amounts), and “Numerical
Quantity-Arithmetic.” The data available from
previous research for the FAA subjects (Sample


battery. Their experimental assessment at time
of entry into training had included four of the
seven commercial tests. As described earlier,
these were the four tests used in derivation of
the Commercial 4-Test Composite Score. The
correlation between the Commercial 4-Test Com-
posite scores and the CSC-ATC Test scores for
Sample 2 was .81. This correlation thus per-

mitted the development of an equation with
which the former were used to estimate the CSC
Test scores for subjects in Samples 1, 3, and 4.
Figure 3 illustrates the relative range and
distribution of the estimated CSC-ATC Test
scores for Samples 1, 8, and 4, and similar in-
formation regarding the existing CSC-ATC Test
data of Sample 2. This figure is of the same

----P 98
240 -+--P 90
o-2-P 75
220 4
| ----Median
200 ]
180
----P 10
160
140
----P 02
120
100 4
Sample 1 2 3a 3b) Tot = 4a 4G Tot
N 212 183 435, 214 649 207 103 310
Type FAA FAA NAVY MAR N+M NAVY MAR NM

Froure 3, Relative Range and Distribution of CSC-ATO Aptitude Composite Scores for FAA,
Navy, and Marine Corps Trainees. (Note: The CSC-ATC test scores were estimated through regression
techniques for subjects of all samples except Sample 2)

18



the majority of the Marines would be able to
qualify. These findings are confirmed by the
data presented in Figure 4. Over 45 per cent of
the FAA subjects of combined Samples 1 and 2
have (actual or estimated) scores of 189 or less;
21 per cent have intermediate scores of 190 to
209, and only 33.7 per cent are in the qualifying
range. For the combined Navy Subsamples 3a
and 4a, the corresponding percentages are 29.8,

189 & less
(189=traditionally
Inon-qualifying for

98.4, and 46.9. For the Marine Subsamples 3b
and 4b, only 10.7 per cent are lower than 190;
20.8 per cent are in the intermediate range, and
68.5 per cent equal or exceed the requirement of
210.

OSC-ATC Test Score Versus MSC Score.
Figure 5 reveals a high degree of correspondence
between level of predicted CSC-ATC Test score
and level of Military (MSC) Test score. (Though

190 - 209
(190=qua li fying
score for FAA

210 & above
(210=recent FAA
ATC selection

O

Semple Military-Test FAA ATC options) in 1962-1963) requirement)
& Type _Score Range NL
125 & > 19.7% 138
3a
Navy 110 - 124 221
109 & < 5
125& > 65
4a 110 - 124 110
Navy
109 & < 31
125 & > 203
Satta 110 - 124 331
Navy
109 & < 106
125 & > 79.5% 151
3b Z,
110 - 12:
arene 4 WALLLLZ 45.4% 33
109 & < 100.0% 1
7 i
125 & > SGLLA 72.4% 29
4b 77,
Matine TIO > 124 22.9 WIENS LLL) 39.6% 48
109 & < 0
125 &> A 78.3% 180
3btad . y ZA,
aprab 110-124 WAESEGLLLA 42.0% al
109 & < 100.0% 1

Fiaure 5. Percentages of Navy and Marine Corps AT
Score Range Having Predicted CSC-ATC Test Scores of

1

‘C Trainees by Military-Screening-and-Classification Test
189 or Less, 190 to 209, and 210 and above.

5



A COMPARATIVE STUDY OF AIR TRAFFIC TRAINEE APTITUDE-TEST
MEASURES INVOLVING NAVY, MARINE CORPS AND FAA CONTROLLERS

IL. Introduction.

Since 1964 the standards for the selection of
personnel for training in air traffic control
(ATC) work with the Federal Aviation Admin-
istration (FAA) have included an assessment of
specific mental aptitudes, skills or abilities. A
qualifying aptitude index, based upon a US.
Givil Service Commission (CSC) battery of six
subtests, constitutes the first of several eligibility
requirements. This screening index is an out-
growth of extensive previous research’*** in
which the six CSC test measures were identified
from among 27 different variables as representing
the best composite of aptitude scores for the pre-
diction of training and job performance. Selec-
tion for controller training is also contingent
upon an assessment of pre-employment experi-
ence, educational background, a medical exami-
nation, and an interview with management
officials. Previous relevant experience, such as
military air traffic control, is one of the more
heavily-weighted selection factors. The qualifi-
cation of a candidate having no previous ATC
experience requires a much higher aptitude-
screening index and either a college degree or an
exceptional career background. The FAA con-
sequently recruits most of its trainees from an
applicant pool of former servicemen. Aside from
other reasons, the implications arising from these
recruiting practices are of sufficient import to
warrant FAA interest and support in the devel-
opment and effectiveness of ATC-selection-and-
training programs of the United States Air
Force, Army, Navy and Marine Corps.

The present investigation was undertaken on
a cooperative basis with officials of the Glynco
Naval Air Station (NAS), Georgia. The Glynco
Training School has the responsibility of pro-
viding instruction and basic training for air
traffic control personnel for the Navy and the
Marine Corps. Plans for the study were first
conceived in 1965 when officials of the Naval

facility visited the FAA’s Civil Aeromedical
Institute (CAMI) for further indoctrination
regarding the underlying research, development,
and effectiveness of aptitude tests and other
screening procedures used in the selection of ap-
plicants for FAA controller training. Naval
officials subsequently discussed the possibility of
being permitted the use of the operational bat-
tery of CSC aptitude tests for experimental
administration and validation on ATC trainee
groups at Glynco. Inasmuch as several policy
reasons precluded this approach, CAML scientists
suggested an alternate approach involving the
use of seven commercially-published test instru-
ments which had been validated in previous
research with FAA trainees.

Although only limited validation data were
available for the seven tests as a group, each had
been identified in previous phases of CAMI re-
search? as a significant predictor of training-
course grades for FAA-ATC students. Fortu-
nately, one phase of this research had involved
the experimental administration of both the
complete CSC-ATCS-Aptitude Test Battery
(before its adoption for operational screening)
and four of the seven recommended tests to a
sample of almost 800 FAA trainees. An analysis
of these data revealed a correlation of .74 between
the composite scores of the CSC battery and the
four commercial tests. With course grade em-
ployed as the criterion, validity coefficients for
the separate subtests of the CSC battery were
found to range from .28 to .56 while those of the
four non-CSC tests ranged from .85 to 54. A
correlation of .52 was obtained between the train-
ing course grade and the overall score for all
tests of the CSC composite. The corresponding
validity coefficient for the four-test composite
was .50.

On the basis of these and other supportive
data, it was assumed that the seven commercially-
published tests would constitute an appropriate



FOOTNOTE

This study is from the Civil Aeromedical Institute, Federal Aviation
Administration, Oklahoma City, Oklahoma. The author is indebted to Lieu-
tenant Commander F. J. Gallagher, Glynco NAS Air Controlman Training
School Officer and Mr. Robert F. Jordan, FAA Air Traffic Representative,
for arranging the study and for the collection of data at the Glynco facility.

Opinions or conclusions contained in this report are those of the author
and do not necessarily reflect the views or endorsement of the Federal Avia-
tion Administration.

Qualified requestors may obtain Aviation Medical Reports from Defense Documentation
Center. The general public may purchase from Clearinghouse for Federal Scientific and
‘Technical Information, U.S, Dept. of Commerce, Springfield, Va. 22151.


Over 200 of the 628 Navy trainees made scores
of 279 or less on this composite compared to only
27 Marines, In each instance however, about 25
per cent of the subjects having such low scorés
represent training-course failures and almost 30
per cent are classed as marginal-pass cases. The
failure rate and the proportion of marginal-pass
cases are contrastingly lower for both the Navy
and Marine trainees who attained scores of 310
or better. The two graphs appear to be almost
congruent with the previous pair which pertained
to the original 4-test composite.

One of the two graphs in the lower portion of
Figure 1 illustrates the screening potential of the
military screening-and-classification (MSC) score
used by the Navy and the other reflects the poten-
tial of the Marine Corps MSC score. The two
MSC indexes are based on different instruments,
as described earlier, but are presumably equiv-
alent and comparable, The data indicate that
the majority of trainees in both groups were se-
lected from relatively high MSC score ranges.
In this respect however, the Marines constitute
the more elite group. Only one of the 259 Ma-
rines had an MSC score of less than 110, com-
pared to 104 of the 626 Navy students. The
overall failure rates, which are not presented,
are 9.3 per cent for Marine, 12.3 for Navy, and
14.8 for FAA trainees of combined Samples 1
and 2. The graph for the combined Subsamples
3a and 4a indicates that almost 81 per cent of
the 198 Navy Ss with MSC scores of 125 or
higher passed the Glynco course with good
grades. About 61 per cent of the Navy trainees
who have intermediate-range MSC scores com-
pleted the course with non-marginal grades com-
pared to 41.3 per cent of those having MSC
scores of 109 or less. The graph for the com-
bined Subsamples 3b and 4b shows that approxi-
mately 77 per cent of the 179 Marines with MSC
scores of 125 and higher were able to pass the
course with good grades. In contrast, less than
56 per cent of the 79 who have Marine MSC
scores within the range of 110 to 124 are cate-
gorized as non-marginal pass cases. A study of
the differences between the Navy and Marine
data indicates that if the number of applicants
should vastly exceed the training demands, the
Navy would be able to improve substantially. its
screening procedures by requiring an MSC score
of 110 or higher of every ATC applicant.

‘The three sets of graphs in Figure 1 are all

i

rather similar. Each of the three aptitude meas-
ures has considerable predictive potential. How-
ever, if the data were extrapolated to determine
the relative screening potential of each measure,
the results would be as follows: (1) Based on
1450 as a minimum qualifying score, the Com-
mercial 4-Test Composite could have been used.
to sereen 39 of the Navy’s 77 failures and 8 of
the 24 Marine Corps failures. However, this
screening would have been accomplished at the
sacrifice of 144 potential-pass Navy cases and 24
potential-pass Marine cases. (2) With the New
4-Test Commercial Composite, a cut between 279
and 280 would theoretically exclude 47 of the
Navy’s 77 failures and 11 of the 24 Marine fail-
ures while simultaneously eliminating 154 Navy
pass cases and 16 potential-pass Marine cases.
(3) The establishment of a screening cut between
110 and 109 would have eliminated 27 fails and
77 pass cases of the Navy and a single Marine
who passed the training course. Based on the
specified screening cuts, the New 4-Test Com-
mercial Test Composite may appear to be some-
what superior to the other measures. On the
other hand, if the applicant pool were rather
limited and training demands were high, it would
represent an impractical screening device.
Differences in Aptitude Levels of FAA, Navy
and Marine Corps Trainees. The bar diagrams
of Figure 2 illustrate the relative range and
distribution of the Commercial 4-Test. Composite
Scores for the FAA, Navy, and Marine Corps
ATC trainees. This composite, which involved
DAT Space Relations, DAT Numerical Ability,
DAT Abstract Reasoning and CTMM Analogies,
is the only measure available for a direct com-
parison of the different samples. The horizontal
line across the middle of the bar diagram shown
for each sample represents the median-score
level. Other points depicted in the figure cor-
respond to the second, tenth, twenty-fifth, seventy-
fifth, ninetieth, and ninety-eighth percentiles.
The median score for the 214 Marines in sub-
sample 3b is higher than for all other groups.
"This median score of approximately 1775 was
attained or exceeded by less than 20 per cent of
the FAA subjects of Samples 1 and 2. At every
point on the scale, the Marines of both Samples
3 and 4 appear to be superior to the FAA trainees
and also substantially better than the Navy
trainees. Based on a comparison of the median
scores, it becomes quite evident that the FAA



general type as Figure 2 and, inasmuch as the
CSC scores were predicted from the composite
scores depicted in Figure 2, the graphic patterns
of the two are highly similar. However, Figure
3 permits an examination of the distributions
relative to previous and current selection stand-
ards employed by the FAA. When the CSC
Test first became operational in July 1962, a raw
score of 190 represented the minimum qualifying

CSC Score Range

score. However, the selection standards were
revised in January 1964, Since that time, a CSC
Test score of at least 210 has been required of
every entrant into FAA ATC training. Figure 3
illustrates that a CSC-ATC Test score of 210
constitutes an exceptionally high score for the
FAA subjects of Samples 1 and 2, whereas it is
only slightly higher than the median of the esti-
mated scores of the Naval trainees. In contrast,

CSC Score Range CSC Score Renge

189 & <. (189
has slways been

Z

190-209. (190
was qualifying

210 & >. (210
is present selec-

non-qua li fying.)

in 1962-1963.) tion requirement.)

Sample Type ATC
Ns 97 53 62 212
F777,
N 82 30 a 193
7
2 FAA og, ED A165, 38.87%
N: 139 98 198 435
Ne 2 52 103 207
+ we gute — ss
N: 20 35 159 214
3b MARINE oy GY 74.3%
Ni 14 31 58 103
Ce cD Ce 56.9%
Ne 179 83 133 395
N: 191 150 301 642
Nz 34 66 217 317
So
3bH4b MARINE oe G4e 8%. 68.5%

Fieure 4. Percentages of ATC Trainees within each

sample having actual or predicted CSC-Test Per-

formance Scores Representing Low, Intermediate, or High ATC-Aptitude Ranges,

14