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UNITED STATES ARMY
SOLDIER CAPABILITY ARMY COMBAT EFFECTIVENESS
"HISTORICAL COMBAT DATA
MAR 1 11981'5)
TREVOR N. DUPUY
GAY M. HAMMERMAN
APPROVED FOR PUBLIC RELEASE;
PREPARED FOR THE
U.S. ARMY SOLDIER SUPPORT CENTER
HISTORICAL EVALUATION AND RESEARCH ORGANIZATION
A DIVISION OF T.N. DUPUY ASSOCIATES, INC.
P.O. BOX 157, 2301 GALLOWS ROAD
DUNN LORING, VIRGINIA 22027
SOLDIER CAPABILITY - ARMY COMBAT E-FFECTIVENESS (SCACE)_
HISTORICAL COMBAT DATA AND ANALYSIS #.
and GAY,/HAMMERMAN \I
Approved for public release; distribution unlimited
-- .Jrepared for
US Army So
Under ContractrDAAG29-76-D-G_0 O,...-Battelle Columbus Laboratories,--Delivery Order No. 1731
Historical Evaluation and Research Organization
A Division of T.N. Dupuy Associates, Inc.
P.O. Box 157, 2301 Gallows Road
Dunn Loring, Virginia 22027
This report was prepared by Trevor N. Dupuy and Gay Hammerman,
It was reviewed by
with the research assistance of Dee Allyson Horne.
Abraham Wolf and Angus M.
Grace P. Hayes, HERO Director of Research.
The paper: "Comments
Fraser participated in the study as consultants.
on the Category IV Problem," contained in Appendix A, was contributed
by Earl Hunt and Marcy Lansman, both from the University of Washington.
The views, opinions, and/or findings contained in this report
are those of the authors and should not be construed as an official
Department of the Army position, policy, or decision, unless so
designated by other documentation.
TABLE OF CONTENTS
Acknowledgements and Disclaimer .............................
Table of Contents ...........................................
Figures and Tables ..........................................
Executive Summary ...........................................
Research and Analysis ...................................
Recommendations for Follow-on Research ..................
Appendix A: Individual Capability and Group Performance,
with Special Reference to Man/Machine Systems .............
Comments on the Category IV Problem .....................
The Interpretation of Aptitude Test Scores ..........
Anticipated Behavioral Characteristics of
Category IV Enlistees ............................
The Use of Equipment ................................
Suggested Further Readings ..........................
Appendix B: Combat Effectiveness and Characteristics
of Society .............................................
1. Troop quality worksheet ..................................
Comparison of scales of troop capability .................
Characteristics associated with troop
capability in combat ...................................
1. Median scores on the Army General Classification
Test for enlistees from several occupations
(data gathered from the World Ward II mobilization
Minimum general intelligence score required for
success in several occupations according to the
General Aptitude Test Battery norms ...................
This study included a survey of historical literature related to
troop quality and capability; a survey of psychological literature dealing
with the relationship of individual aptitude to group performance, with
special attention to the group performance of low-aptitude individuals; a
statistical comparison of quantified ratings of the combat effectiveness of
17 national military forces since 1945 with demographic, educational, and
other statistical characteristics of the nations involved; and a survey of
collections of combat data for the purpose of identifying units with unusually
high combat effectiveness, and also of identifying detailed combat data on
relatively small units (regiments and battalions) that would make possible
quantitative analysis of unit combat effectiveness at those levels.
The study concluded that superior leadership and training are required
to compensate for low troop quality, with leadership of prime importance; that
there is a strong statistical association between the combat effectiveness of
armies during the past 40 years and national characteristics of male literacy,
household size (negative),
birth rate (negative),
and temperature of the capital
city in the hottest month (negative); that the high level of correlation found
indicates the probability that a formula could be derived to estimate the
effectiveness of any two forces in a war game; and that detailed data on combat
experience is available for units of exceptionally high combat effectiveness
and for both sides in combat between battalions and regiments.
The study report includes recommendations for further research in the
quantification of troop capability and its effect on combat.
bibliography accompanies the report.
A fully annotated
- ARMY COMBAT EFFECTIVENESS (SCACE)
HISTORICAL COMBAT DATA AND ANALYSIS
In fulfillment of the objectives of the SCACE Study, HERO was
asked to provide a literature overview of historical and other related
materials, to conduct such relevant historical analysis as was possible
within the brief assigned time frame (45 days), and to identify data
gaps and recommerdfollow-on studies for which a need was found.
For purposes oF HERO's work, the following definitions have been
and an effort has been made to use the terms thus defined
consistently in this report:
e Quality is the basic aptitude the soldier brings with him when
he enters the Army. In the US Army today it is measured by the
amount of prior schooling and scores on standard aptitude tests.
* Capability is the skills and aptitudes the soldier brings into
battle, after quality has been tempered by training and/or
e Combat effectiveness is the capability of units. It is in part
dependent upon troop capability, but is also dependent upon
leadership, tactics, and other factors.
Research and Analysis
The following research efforts were carried out:
a. Historical materials
Following consultation with staff military historians, the following
categories of relevant literature were selected for investigation:
9 classical military studies dealing with troop combat performance
# memoirs of commanders known to have treated the subjects of
training and combat performance
* accounts of combat from the point of view of the individual
soldier that might be expected to provide insights on troop
quality and troop performance
% materials dealing with the performance of troops regarded as
of very high or very low quality
e analytic accounts relating training to combat performance
In carrying out this research, the US Army Military History
Research Collection at Carlisle Barracks,
and the guidance
of its staff historians were used, as was the Army Library collection
at the Pentagon; a computer-assisted search of Library of Congress holdings
was also carried out.
The literature examined, which stretches from the early 16th Century
(Niccolo Machiavelli*) to the most recent Arab-Israeli war (Luttwak and
produced a clear consensus
on a number of points related to
e leadership is crucial to combat success
@ unit cohesion and loyalty are crucial to combat success
3 unit training under realistic conditions, and/or combat experience,
is extremely important to combat success
e disci:iline and drill are valuable in forming capable soldiers and
* the factors listed above can outweigh opposing superior numbers
* panic in combat is a function of the group environment rather than
of the individual's personal qualities, but the action of a few
individuals can start or stop it.
Very little is said specifically about troop quality or capability
in this literature.
It may fairly be stated that most of the writers
reviewed assumed a normal distribution of inherent quality as a given
for combat troops, and also assumedthe desirability of at least basic
general and military education.
For works that deal with quality more
explicitly than most, see Baynes, Chuikov, Machiavelli, Marshall 1956,
Names inserted in the text within parentheses refer to entries in the
Since it appeared that a reasonably normal distribution of troop
quality was an assumption for most authors, HERO sought extreme cases
in which a force of acknowledged low-capability troops fought another
representing a national demographic cross-section; HERO also sought
examples of individual units regarded as made up of elite troops or
very poor troops in order to compare their combat performance with their
assumed quality. A number of examples of both were identified.
example, most armies during the Thirty Years' War of the 17th Century
were composed of either mercenaries or impressed troops, or both, units
made up of what is usually referred to as the "dregs of society," while
the highly successful Swedish army of Gustavus Adolphus, in the same
wars, was a truly national army.
Another area in which extreme cases were sought was that of prolonged
and especially deadly wars that severely drain manpower. Cases identified
were the case of Paraguay in the Lopez War of the mid-19th Century, of
Germany near the end of World War II, and of both Union and Confederate
armies near the end of the Civil War. There was not time within the
limitations of the present study to develop appropriate bibliography for
these cases, much less to conduct research,
but further study might well
Another, probably more promising, area for exploring
troop quality and capability appeared from the literature
Israel Defence Forces induct almost all Israeli young men
women), and serve an important educational role for those
the impact of
tary education, especially Israelis of non-Western origin. Luttwak and
Horowitz, Appendix 5, includes some relevant material on troop capability
For example, the IDF discovered that providing concentrated
elementary-school education in the first months of military service does
not improve the chances of military success for those who take it, and
consequently reverted to its earlier practice of giving this training at
the end of the three-year period of service. Further research in IDN
reports and through interviews would appear desirable.
Results of training and unit readiness evaluations and
A preliminary survey of material in this area, consultation with
Army Research Institute personnel engaged in evaluation of training and
proficiency, consultation with the COTR for this study, and examination
of the extensive bibliography for the SCACE study, prepared by the COTR,
confirmed that the COTR had investigated all readily available material
in this area. It appeared that a study of the relationship between success
of individual soldiers in field training exercises on the one hand, and
the quality of individual soldiers as measured at induction and their
capability as measured by job-performance tests (SQT scores) would be
Such a study should help validate SQT scores and make
a contribution toward establishing a predictor for individual and crew
performance in combat.
Theoretical data pertaining to the objective of the SCACE
A research psychologist was given the task of providing an overview
of relevant theoretical material relating individual performance to
aggregate group performance.
He conducted a preliminary survey of the
literature and found:
* The most relevant research is military related.
It was determined
that this research has been fully explored by the COTR.
* A search of the massive literature on the relationship of individual
to small-group (crew-size) performance would require more time than
was allocated to this investigator under the contract.
appeared doubtful that such an effort would yield significant
amounts of relevant material.
* In general, research studies in this field tend to use college
students as subjects, so that the question of a high proportion of
low-aptitude (low-quality) subjects (as measured by standard tests
or educational level) is not dealt with.
* Industrial studies, which deal with the relationship between training
and performance and might be expected to be useful, are not a
promising source, because they rarely include a sizable proportion
of low-aptitude personnel.
It was therefore decided, in consultation with the COTR, that the most
useful theoretical contribution for this task would be an overview of the
relationship of cognitive skills to training and performance, with special
reference to man-machine systems, (,nd the problems that still remain to be
solved in this area.
A summary of this work is attached as Appendix A.
Assessment of correlation between historical data and data on
combat effectiveness of soldiers, and relevant analysis
"a. Preliminary investigation of the relationship between national
climatic statistics and troop vapability
This task .was designed as a first step toward establishing a possible
link between troop quality and the performance of units in combat.
first exercise carried out in fulfillment of this Ã½ask was the scaling
(ranking) of 17 armies of the oast 40 years as to the combat effectiveness
of their forces in battle.
Ideally, it would have been desirable to scale the average
of the individual soldiers,
since troop capability is the independent variable
of this study. However, there is no way that troop capability can be seen
in isolation when one examines the performance of soldiers at the nationalforce level.
Performance at this level inevitably reflects additional
factors, including especially quality of leadership. Combat effectiveness
presumably includes troop capability, and is the only way we now have of
examining troop capability at the national force level.
17 national forces (armies)
were scaled according to the quality of their
The scaling described above was done by a group of highly qualified
military historians, using the method of paired comparisons, a simple,
but widely acceptedand mathematically rigorous procedure.
scalings of armies were then compared with a group of national demographic,
economic, and other statistics in an effort to find possible associations
between national armed force capability and national statistics. Appendix
B presents a discussion of the results, together with tables showing the
scalings and associations.
Some of the conclusions of these exercises are
# The military historians who ranked the 17 armies judged the Germans
in 1943-44 to have had the most effective forces, with the Israelis
during the period 1967-73 ranked second.
The least effective forces
were those of the Iraqis and Syrians during the latter period.
e US forces during the period 1966-70 were evaluated as somewhat lower
than US troops of 1943-44 and 1951,
but higher than Japanese or
Soviet troops of 1944.
forces of today,
(No effort was made, of course,
to rate US
since judgments were made only on the basis of combat
a Two characteristics related to demography were very strongly negatively
associated with national combat effectiveness.
* One characteristic related to education was very strongly positively
associated withcombat effectiveness:
* One characteristic related to climate was strongly negatively
with combat affectiveness.
temperature in the hottest month
e A number of other factors tested were associated with combat effectiveness
less strongly or not at all.
(See Appendix B for details.)
* The strong associations noted atL'>v
derive a formula for estimating
capability) of any given national
As part of this same task,
indicate that it may be possible to
tie combat effectiveness (including troop
force being analyzed or war qared.
a review of the findings of HERO's Quantified
on the combat effectiveness of national
Analysis of a large number of combat engagements --
carried out during the past 10 years --
has shown that there is a quaTntifiable
factor in addition to numbers of men and firepower that helps determine the
outcome of battles, and that this factor differs from division to division anc
from national force to national
ative combat effectiveness
This factor is termed by HERO the relThe CEV is assumed to include troop
capability, along with leadership training.
Thus far it
been possible definitively to isolate any of these subfectors,
quality, from the total CEV,
but the unquestionable existence of CEVs does
show objectively that numbers and weapons alone do not determine battles.
can be readily demonstrated that numbers alone do not
and CEV is the term used In the Quantified Judgment Model
quantifiable qualitative difference between two forces of equal
size and weaponry.
When the scale of force effectiveness derived from the judgment of
which has been described above,
was compared with a
scale based on the CEVs of the national forces under consideration,
two scales agreed closely.
Review of data in HERO Engagement Data Base for relevant
A search was made in the HERO Engagement Data Base for units that
had unusually high CEVs,
ir the hope that demographic and other relevant
data about the troops composing these units might help establish a link
between individual capability and unit performance.
The division identifed
as having a particularly nigh CEV is the 88th Division, in its performance
against German units in Italy in 1944.
It was not possible within the time
frame of this study to carry out any research on the relationship of the
relative combat effectivene. ; of divisions and demographic or other stat'stics,
but follow-on research would appear promising.
See Reconmendations for
Follow-on Research, below, for a fuller discussion.
Search for detailed combat data on US regiments and battalil.ns
In pursuit of this task, a very promising source of data was discovered
in the US Army Military History Research Collection at Carlisle Barracks,
Pennsylvania. This is a collection of raw combat data copiled by the US
2d Division, an outstandingly successful World War I combat division.
2d Division, following the war, collected the war diaries of all the Ge-ian
units that had opposed it in battle in 1918 and also compiled its own 4ar
diaries and 'hose of all its subordinate units. This data will make possible
the kind of small-unit combat dnalysis for which this task of the current
study sought data.
there are some groups of information on US regiments and
battalions in the Federal Records Center.
The chief difficulty in determining
the 1;cmbat effectiveness of these units, and thus providing a iink between
individual performance and division-and-higher perforrance, is the task of
reconstructing the combat data for opposing forces. This work would require
a large investment of time, but it
is believed to be feasible, and could
have extremely useful results.
The following conclusions emerged from a consideration of the military
historical literature reviewed for this project, the preliminary statistical
analysis described above, and HERO's past work on the relative combat
effectiveness of large units and national forces:
o There is almost certainly some tradeoff between the factors that
compose combat effectiveness; that is, leadership and training almost
certainly can compensate to some extent for low troop quality.
However, it is obvious that superior leadership and training would
be required if quality were low, not just average leadership and
* There also seems to be some synergistic effect among troop capability,
training, and leaaership. Good commanders raise the capability of
their troops, and with good troops a commander performs better.
Leadership is especially important, because of its impact on training,
and the impact, In turn, of training on troop capability. This does
not mean that low troop capability does not have a degrading effect on
combat performance, and it does not mean that a predictor for degraded
combat performance cannot be found, but it does complicate the task.
a National combat effectiveness appears to change very slowly over time.
For example, despite the Bolshevik revolution and many years, Soviet
CEVs with respect to the Germans were only slightly higher than those
for Russia in World War I. German CEVs relative to the Western Allies
for World Wars I and II are also close. These facts indicate that
while a country may expect to coast for some time on the intangibles
of troop quality, leadership, discipline, training, and tactics, a
high level of combat effectiveness, once lost, may be hard to restore.
* Preliminary exploration of the relationship between the combat
effectiveness of armies during the past 40 years and a variety of
national demographic, economic, and other factors indicates a strong
association between a number of these factors -male literacy, household size (negative), birth rate (negative), and
temperature of capital city in the hottest month (negative) -- with
national combat effectiveness. Two points may be made about this
One is that some of the statistics that
characterize an industrialized society are also associated with
high troop quality in the middle-to-late 20th Century.
is that one of these factors, male literacy, is one that can be
identified in the individual
soldier and thus controlled for the
is possible that it
could become the basis for a
predictor of army combat effectiveness.
important to under-
that the findings so far do not give any reason to
believe that increasing literacy in a given amy will significantly
increase combat effectiveness.
e It seems possible that a national army that represents an economic,
and educational cross-section of the nation will generally
be more combat effective than one that includes low-capability
individuals in sharp disproportion
to the general population.
appears to be a hypothesis worth tasting.
Both -volunteer and con-
script armies vary in their troop quality, with no clear pattern
but there is some reason to believe that cross-section
armies are of higher quality.
The German armies of World Warsl and
I1, the Israeli army of the present, and the US and British armies
of World War II,
almost certainly the most combat effective armies
of the 20th Century, have all been cross-section,
There is some evidence that the US Army that fought
which (for a peacetime army) included a very high proportion
of the US population, was of somewhat higher capability than the less
representative, although also conscripted, army that fought in Vietnam.
S.L.A. Marshall believed it to be better in some ways than the US
Army of World War II (Marshall
an observation which does
nothing to support (or deny) the present hypothesis but does indicate
how fine the army in Korea was.
(See Moskos 1980 for an excellent
discussion of the strengths of a representative army.)
* The work carried out thus far has yielded no method for quantifying
the impact of troop quality or capability upcn weapon effectiveness,
on the basis of historical data and analysis,
but several research
tasks have been defined that offer good probability of contributing
to this quantification.
Recommendations for Follow-on Research
The SCACE Study seeks to clarify and quantify the links between the
quality or capability of the individual soldier and the effectiveness of
the weapons system, small unit, larger unit, and force.
Some of these
links are considerably clearer than others.
In particular, there is a
good deal of data on the link between the capability of the soldier before
combat and his performance in combat.
There are also some well-supported
hypotheses about the quantitative role of human factors, or relative combat
effectiveness values (CEVs) at the division and force level, based on
HERO's past work in this field. The chief need, therefore, is more quantifiable information about the role of human factors at the small-unit
level and up through the regimental level,
and a methodology for relating
these Quantities to each other.
Strongly Recommended Research
HERO has carefully considered a number of possible follow-on studies
suggested by the present work, and has selected three to recommend strongly,
on the basis of their contributions toward filling these identified needs,
as well as of the availability of data.
A Comparison of the Combat Effectiveness of Selected World War I and
World War II Divisions
HERO's QJM methodology for assessing, consistently and reliably, the
relative combat effectiveness of opposing forces in battle has shown that
in the Italian Campaign of 1944 the relatively unsung 88th Infantry Division
(a National Army organization) consistently performed better than any other
American division involved in the campaign.
Interesting corroboration of
this quantitative analytical assessment comes from the war diary of the
German Tenth Army,
in which the 88th Division is referred to as "shock
troops"; the record further shows that whenever the 88th Dvision was committed to combat
the Germans shifted reserves to that sector of the front.
The extent to which the superior performance of the 8-9th was due to better
leadership, better training,
better quality of manpower, or some other
reason or reasons cannot be determined without further research.
research it may be poss-,ble to tell whether or not superior manpower
quality was a contributor to the success of the 88th Division.
"There are other possibilities for assessment of relative combat
effectiveness of American divisions In Italy and Northwest Europe in
World War II, divisions for which HERO has already assembled some data,
including the 3d, 34th, 36th, and 45th Infantry Divisions and 1st Armored
Division in Italy, and the ist, 2d,
29th, 26th, 35th, and 90th Infantry
Divisions and the 4th, 5th, and 6th Armored Divisions in Northwest Europe.
In World War I, the US 1st and 2d Infantry Divisions have consistently
been judged by informed military opinion to be almost certainly the best
divisions in General Pershing's AEF.
Statistics on casualties, ground
gained and prisoners taken, and other measures of combat effectivenes
compiled by the Statistical Division, War Department General Staff, under
the direction of Col. Leonard P. Ayers, appear to confirm this .ssessment.
A more reliable and precise method of confirming the superiur combat
effectiveness of the 2d Division is now possible.
In the course of the
present stuoy, HERO discovered a collection of raw combat data on that
division that will make possible an analysis of the 20 or more engagements
of the 2d Division in World War II by HERO's QJM methodology.
collection consists of the war diaries of all the German units that o,,posed
the 2d Division, together with its own written combat ordels and thos-Ã½ of
its subordinate units.
Carrying out this analysis will quantify the alhost
certain combat effectiveness superiority of the 2d Division.
With the high standard of combat effectiveness of two divisions from
two separate wars established and quantified, the reasons for this superiority, in comparison to performance of other divisions engaged at the samre
time, can be sought, and the possible role of troop quality and capabiliL,,
and of various demographic and other national statistical characteristics,
as predictors of combat effectiveness can be assessed.
The objective of this follow-on study would be to use the promisinq
data available on these two divisions to seek a precombat predictor of
This study is very strongly recommiended.
Small-Unit Combat Effectiveness Assessments
As noted above, one of the greatest needs in SCACE Study research is
for quantified data on unit performnce in small-unit actions,
of information has been difficult to obtain,
below '.he division are rarely complete.
since combat records at levels
If complete records were available,
it would be possible to carry out QJM analyses for small units.
then be possible to relate individual soldier capability to small-unit
and also to develop aggregation factors relating small-unit
performance to the performance of divisions.
A very promising resource is now available for carrying out this
The 2d Division collection of records, compiled after World War
includes not only all written division combat orders and the war diaries
for units opposing the division, but also the orders for subordinate units
of the division.
This will make possible low-level QJM assessments,
since the corresponding division records are also available,
can be made and aggregation factors derived.
Since preliminary research has indicated that low-level data of quality
adequate for QJM analysis can also be found -- with difficulty -- in the
World War I1 records, the relevance of World War I experience to that of
World War 11 can be tested, and at the same time the nature of trends in
low-level combat can be assessed.
This research could be carried out in two stages:
9 The QJM analysis of the World War I performance of small-unit
components of the 2d Division, and a comparison of the results with
findings for zoe performance of the division.
* The compilation of combat data for selected small units in World
War II; the reconstruction of data for enemy foices facing them;
the QJM analysis of the results; and the comparison of QJM findings
for these units and for the divisions of which they are components
with those for the World War I components of the 2d Division, and
The objective of this study would be to quantify the relationship
between small-unit performance and division-level performance.
is strongly recommended.
National Manpower Quality and Combat Effectiveness
In the present study, a beginning has been made in exploring the
relationship between national demographic, economlic, and other statistics,
on the one hand,
and the combat effectieness of armies,
on the other,
(See Appendix B.)
In another approach to the question of comparative combat effectiveness,
HERO has made consistent, and demonstrably reliable, comparisons of the
combat effectiveness of opposing national armies in World War I,
II, and the Arab-Israeli wars.
It is clear that to a large extent the
differences in national combat effectiveness from one country to another in
these wars are a reflection of professionalism,
At the same time,
leadership, and training.
it appears likely that cultural and technological differ-
ences in the societies have influenced the quality of military manpower and
the comparative battlefield performance of individuals and units to some
thus far unquantifiable extent.
If it should be possible to find some way to compare the quality of
manipower of the various armies of these wars, and also to compare their
military training systems and level of leadership,
the significance of
manpower quality could be assessed and at least roughly quantified.
Following are the next steps to be taken in this effort:
* Preparing plots of data already gathered and examining them for
relationships that may not be detectable by the method already
carried out, i.e.,
calculating a corvelation coefficient.
@ Refining the scaling of national combat effectiveness and establishing
a broad consensus on the scaling by obtaining the judgments of a large
number of both military historians and experienced combat troop com-
ma nde rs.
* Considering other possible statistical indicators of national combat
# Broadening the statistical base.
Preparing reliable statistics for
the earlier periods involved (pre-World War II) will require an
appreciable investment of time.
* Examnining the effect of time lags on the correlation between force
effectiveness and demographic, economic, and other national characteristics.
It may be that the characteristics of a society that produces
effective combat forces are effective only after a delay in time.
The objective of this study would be to derive and quantify a predictor
troop capability, or national troop combat effectiveness,
and/or other statistics.
The study is strongly
Other Desirable Research
The following research projects were juuged desirable but of lower
Investigation and Analysis of Relevant Israeli Experience
The Israel Defense Forces (IDF),
generally acknowledged to comprise
a highly effective combat force, has a great deal of experience in providing
basic education and training to its members, and in making effective use of
troops with low educational levels and psychomotor skills. Some IDF reports
on these subjects are known to exist, and some interviews with appropriate
officers should be easy to arrange in Washington, or in Israel if necessary.
The first step in such a study would be to determine whether this material
has already been exploited and made readily available in this country.
it has not, this would appea- an extremely useful project requiring a relatively low investment of time and money, even allowing for the need for
The objective of this study would be to gather data un Israeli experience
with troops lacking literacy, elementary education, and/or psychomotor skills
required for many current military occupations.
The feasibility portion of
this study is strongly recommended,
Volunteer vs. Conscript Army
with follow-on as appears appropriate.the Franco-Prussian War
of the quality of US Army soldiers today is often related
to the issue of the relative capabilities of a volunteer military force and
a conscript army.
Probably the closest comparison of battlefield performance
of a volurteer army against a conscript army can be found in the FrancoPrussian War campaigrs of 1870.
The French Army was nominally conscript but
actually consisted mainly of long-service volunteers; the ranks of the
Prussian army were filled with short-service conscripts.
In general, the
French soldiers were of higher capability than the Prussians, but the Prussian
noncommissioned officers and officers were superior to the French. There
appearF to have been no assessment of the relative performance of these armies
in terms of the quality of their soldiers, or of the way in which this quality
was affected by the voluiiteer or conscript nature of the army.
Comparison of Marine Corps and Army Troop Bapability
The Marine Corps has consistently been somewhat more selective in
recruitment than the Army, and to some extent it is regarded as an elite
military organization. Compdrison of the performance of comparable Marine
and Army units in World Wars I and II, and in Korea, together with comparisons of their manpower quality aid training and doctrine, could be
expected to provide useful findings on the role of troop quality and
capability in combat effectiveness.
The fact thAt the US 2d Infantry
Division in World War I -- dn outstanding division for which detailed
records are available -- was composed of one Marine Corps brigade and
one Army brigade enhances the possibility of carrying out a significant
Army-Marine Corps comparison.
Comparison of Troop Quality and Capability with Performance in SimulatedCombat Training Exercises
The Army Research Institute carries Out research on the effectiveness
of various field exercises as training devices, with quantified results,
Enough information on the individual soldiers participating in these exercises
is available from ARI's work to permit analyzing the relationship between
soldier quality (as measured at induction), soldier capability (as measured
by SQT scores),
and the performance of individual soldiers and small units in
Since quantified data on these relationships
is important for validating degrading factors for weapon effectiveness,
research should be carried out.
H, Historical Survey of Manpower Quality in US Army Combat and Support
Units in the 20th Century
Whereas there is considerable agreemert that the overall quality of
manpower in the All Volunteer Army (AVA) is substantially lower than it
was when Selective Service was supplying manpower by conscription, there
are two almost-contradictory opinions as to the effect on the combat arms
of the Army,
The first view is that the lower quality has a deleterious effect on
the combat arms, for it exists at a time when modern technologically
sophisticated weapuns make it very difficult for low quality soldiers to
The second view is tha. actually the quality of manpower in the combat
arms today is comparable to that in the combat arms in peace and war over
the past 50 to 80 years, and that a return to conscription would not be
likely to improve it.
The admitted reduction in quality is held to have
affected the support arms and services only.
A study that would evaluate the quality of manpower over this period,
its implications in terms of combat readiness in the 198gcs, and the possible
effects of a return to conscription is highly recommended.
Differences between Elite and Poor Units
There have long been two schools of thought about the creation and use
of elite units. One school contends that elite units, created either from
highest quality men or from average men very highly trained, make the best
use of available manpower,
The other school maintains that any
contribution of elite units to overall military combat effectiveness is more
than offset by reducing the motivation of men in average or mediocre units,
A comparison of the relative combat effectiveness of elite and nonelite, or admittedly poor units, and of the soldiers in each, would make a
direct and significant contribution to the objective of the SCACE Study.
A feasibility study could rapidly determine whether sufficient data for such
a study would be available.
As indicated in the body of the report,
there is virtually no
historical bibliography dealing specifically with the quality or capability
The present bibliography is made up of those works that could
be found that included substantial and useful references to troop quality,
or capability, or to the relationship between quality, training, and combat
Whenever possible, specific page references to useful material
have been given.
Ardant du Picq, C.J.J.J.
Ancient and Modern Battle.
Translated by John N. Greely and Robert C. Cotton. New York:
This classic, whose author was killed in the Franco-Prussian war, deals
at some length with combat behavior.
Ardant du Picq says nothing
specifically about trocp quality, assuming a soldier who is "strong,
apt, vigorous, trained....
(p. 99), but stresses leadership and espeArdant du Picq speaks of the discipline that is
cially unit cohesion.
not imposed by superiors but comes from "the mutual supervision of
groups of men who know each other well." (p. 96)
He stresses the importince of keeping the personnel of combat groups as unchanged as possible, and thus producing "brotherhood, professional knowledge, sentiment,
above all unity." (p. 96? "The last chapter deals with the author's views
on national characteristics of various countries and what impact he
believes they have on military matters.
Baldwin, Fred Davis. The American Enlisted Man in World War I. Doctoral
dissertation, Princeton University. Ann Arbor, Mich.: University
Microfilms International, 1965.
This useful work gives the socio-economic background of enlisted men in
World War I, describes the aptitude testing carried out and gives score
results, describes training, and discusses soldier attitudes and adjustment.
It does not deal with combat performance.
Morale: A Study of Men and Courage: The Second Scottish
Rifles at the Battle of Neuve Chapelle, 1915. London: Cassell,
This is an excellent case study on combat performance.
morale as the soldier's determination to do his duty to the best of his
ability in any circumstances, so that morale and good combat performance
are almost synonymous in this work.
Pride in doing a good job and in
oneself are the most important elements of morale, Baynes says.
stresses the importance of training, and especially the inculcation of
esprit de corps.
He believes that the feeling of belonging, the trust
in the group, are of the greatest importance.
The unit he studied suffered 70% casualties in its five-day battle, but carried out its missions
as ordered and held its position until relieved.
The book includes much
detail on the battalion's individual and unit training, and on the social,
economic, and educational background of its officers ard men.
Chuikov, Vasili I.
The Battle for Stalingrad.
Translated by Harold
Silver. New York: Holt, Rinehart and Winston, 1964.
Chuikov, commander of the 62d Army in the defense of Stalingrad, stresses
throughout his narrative the skill and courage of the individual soldier
and the impact these factors had on this desperate battle.
believes that the quality of the Soviet troops, plus superior leadership
and tactics, made the difference against initially superior German numbers,
and he gives numerous convincing examples.
(See especially pp. 70, 97-99,
107-08, 146-47, 153-54, 157-58, 192, 276-77, and 308).
The role of the
individual under conditions of street fighting was apparently especially
important: "It was the soldiers of the 62d Armny who understood more
quickly than anyone else what city fighting means, and learned more quickly
and better than the enemy to make use of streets, buildings, basements,
staircases, factory chimneys, and the roofs of houses." (p. 308) Chui\ov
attributes the soldiers' motivation to patriotism, Communist training, and
the propaganda efforts of the political workers attached to the army.
Blanche D., Jean E. Keith and Herbert H. Rosenthal.
The Corps of
Engineers: Troops and Equipment, pp. 355-390.
II: The Technical Services. Washington: Government Printing Office,
A good case study on the recruiting and training of officers and enlisted
persot.nel for highly specialized combat tasks, in this case, the conduct
of amphibious landings. Vigorous and successful efforts were made to
recruit men with marine and other appropriate experience for the Engineer
Amphibian Command, but the comiiiand also had to absorb large numbers of
Of the first 2,788 men assigned to the EAC from
replacement training centers, only 49% scored at Grade III or better,
whereas a normal distribution would have placed 69% in this category.
(p. 366) Training programs had to be adjusted accordingly. The importance of recruiting aood trainers is stressed, along with the importance
of realistic training generally, and the special importance of ongoing
training following combat experience.
Crane, Stephen. The Red Badge of Coura e.
Library), 19â€¢7Tirst published in 1895).
Random House (Modern
Although a work of fiction written before its author had any personal
experience of military combat, this book is widely praised by military men
for Its realistic portrayal of combat experience. Crane's sources were
published and oral
reminiscences of Civil War soldiers,
The following ch 'ar-
acteristics of combat relevant to the current study emerge: the sense of
security and identity provided by one's own unit; the nonabsolute nature of
courage..-a man will generally run or fight effectively depending on how the
rest of his unit is behaving rather than from any innate cowardice or bravery;
the importance of familiarity with combat conditions for effective fighting.
The Army of Frederick the Great.
Frederick's army was partly native (Pomeranians were highly regarded), and
partly foreign mercenaries.
Its comlmander emphasized the importance of
drill and tactics to attain absolute obedience and loyalty. After two to
three years of basic training in drill and tactics, officers and men
received further training in accordance with their ability. Frederick
regularly held drills and maneuvers to maintain morale, assure readiness,
and, in the case of maneuvers, to experiment with new tactics and train
crconrnders. Frederick believed in esprit de corps, but stressed discipline
above all, asserting that the officer should be feared more than the enemy.
The Army of Maria-Theresa: The Armed Forces of Imperial Austria,
New York: Hippocrene Books, 1977.
A chapter on "The Men" (pp. 47-62) describes the recruiting practices;
backgrounds of recruits, including ethnic groups, occupatiors, and ages;
the organization of an infantry conpany, and the ranks and duties of noncommissioned officers. Duffy suggests that Frederick the Great's army
was better on offense, Maria Theresa's better on defense. He states that
Frederick's harsh discipline led to a good many Prussian des-tions to
Firth, C.H. Cromwell's Army: A History of the English Soldier During the
Civil Wars, the Commonwealth, and the Protectorate, 3d edition.
London: Methuen; New York: Barnes & Noble, 191-92.
A valuable work, based on much research in contemporary iecords and
Includes much detailed information or recruiting practices,
quality of troops, and training.
Fraser, Angus M., Nehemiah Jordan, and John K. Moriarty.
Institute for Defense Analyses,
on an Amnes-y Program in Vietnam....
IDA Internal Note N-394.
Economic ar Political Studies Division.
.;a. , October 1966.
These papers, ba. ,d on 59 interviews with Vietnamese who came over from
the Communi' t forces in the Chieu Hoi (Open Arms) program, provide some
useful information on motivation and morale in Communist Vietnamese forces.
The role of the three-man cell in infantry units, with its family-type
bonds, is mentioned.
George, Alexander L. The Chinese Communist Army in Action: The Korean War
and its Aftermath. New York: Columbia University Press, 1967.
Chapters 8-10 (pp. 152-96) of this work, which is derived from extensive
interviewing of captured Chinese Communist soldiers in the Korean War,
explicate in detail the reactions of the indoctrinated People's Liberation
Army soldier to battlefield conditions which seemed to contradict what he
had been taught. While not immediately relevant to the present study,
George's work provides an Asian perspective on the question of troop behavior
Robert Speller and Sons,
In his memoirs, marginally useful for the present study, General Gough
stresses the importance of military education and training, and also the
character of the British soldier as he sees it--marked by calm and
endurance on the battlefield.
He believes that loyalty to the nation and
willingness to sacrifice for it is bound up with, and partly results from,
the individual's loyalty to his town and region.
Grover G., Jr.
Fighter Group, Montgomery, Ala.:
The Life and Times of the 4th
Brown Printing Co., 1946.
This is unit history by a member, anecdotal, but with useful infomration
and insights. The US 4th Fighter Group was made up of US volunteers who
had jDined the RAF before Pearl Harbor, many of them after being rejected
by the US Army Air 'orps for failing the physical examination or lack of
college education, or after having washed out of pilot school.
The unit had the most successful record, in enemy planes downed, of any
fighter group based in Britain. Throughout, Hall attributes the success
of the group to the superb leadership of its comlmander, Colonel Blakeslee,
and the unusually high motivation of his men. An interview with a World
War II fighter pilot and military historian, conducted in the course of
the present study, has confirmed the exceptional air combat leadership of
This historian also pointed out that another fighter group
based in England, the 56th, also under exceptional leadership but made
up of pilots whose backgrounds were indistinguishable from those of other
US pilots, compiled a record virtually as good as the 4th's, with the two
groups clearly outperforming all other fighter groups. Leadership appeared
to make the difference.
Heavey, William F. Down Ramp: The Story of the Army Amphibian Engineers,
Infantry Journal Press, 1947.
This book covers some of the same material as Coll and others 1958, and
also describes the performance of the Special Brigades of the Engineer
Amphibian Command in combat.
Again, training is stressed, and described
in considerable detail.
The special efforts to recruit officers with
sdiling, power-boat, and shipbuilding experience, the careful efforts to
tailor training to the specific tasks the units would perform, and the
descriptions of combat results, make this material relevant for the present
Oxford University Press, 1949.
Kippenberger's account of conmnanding New Zealand infantry
and armored troops in Greece, Crete, Libya, Syria, Africa, and Italy in
World War II. While he does not discuss quality, as measured by education
and aptitude, per se, Kippenberger does discuss soldier capability, emphasizing the importance of realistic unit training in achieving it.
Kippenberger stresses the importance of battalion unit cohesion and esprit
He emphasizes the roles of unit history, drill, ceremonial parades,
games, and physical appearance in building soldier morale and unit cohesion,
and cites examples of poor discipline, training, and morale leading to poor
combat performance (pp. 48, 55, 175, 345).
For force combat success, he
stresses above all coordination of infantry and armored forces; for the
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success of the individual units, he stresses unit cohesion and ongoing,
realistic unit training.
Kippenberger places tremendous emphasis on unit
cohesion, loyalty to the unit (platoon, company, battalion), and loyalty
to New Zealand.
He stresses the value of drill discipline In building
Lifton, Robert J. "Advocacy and Corruption in the Healing Professions."
In The Social Psycholoqy of Military Service, edited by Nancy L.
GoldUman and David R. Segal.
Beverly Hills, Calif.; London- Sage
A study of the way in which attitudes and conduct were formed under the
pressures of combat experience in Vietnam. Useful for the treatment of
attitudes and reactions in combat-experienced men.
and Dan Horowitz.
The Israeli Army.
This book provides considerable information on the makeup and training of
a universal-service national army generally ranked high among 20th Century
armies. The esprit of the elitist Palmach during World War II (pp. 19-21)
is discussed, as are the demographic makeup of the Haganah in 1947 (p. 23);
decentralized command procedures (p. 54); leadership (pp. 61-62, 85-86);
trainirg, including "black-box" vs. technical-understanding approaches to
high-technology training (pp. 190, 200-01); factors characteristic of Arab
and Israeli societies which the authors see as greatly affecting their
relative combat effectiveness (pp. 283-86); and military pros and cons of
the elite youth-group-based Nahal (Appendix 1).
Appendix 5 (pp. 438-46), extracted from 1962 Israeli Defense Forces report
on education in the IDF, includes much highly relevant information: The
IDF is an important educational agency, especially for Israelis of oriental
Jewish background, but it has been found that literacy education given at
the beginning of military service does not improve the soldier's military
capability; this education is therefore given at the end of the three-year
term of service, with much better success and resulting benefits for the
soldier in civilian life. There is a high correlation between success in
the IDF and prior educational level.
Although success is achieved disproportionately by the better-educated soldiers of Western origin, and although
there have been charges that discrimination against oriental Israelis exists
in other areas of Israeli society, almost no charges of discrimination have
been made against the IDF.
Military jobs requiring technical skills are
most successfully filled by soldiers who score high in tests of psychotechnical aptitude, including manipulation of mechanical tools, and when
these tests were changed to give more weight to the rapid-hand-movement
skills of the Yemenrte Israelis and less weight to tool manipulation, the
tests were no longer good predictors of success in technical jobs.
In The Prince and the Discourses.
New York: Ranlomn House (The Modern Library-,-750
Machiavelli, better known for his diplomatic career, had also organized,
trained, and commanded a citizen army when he wrote the Discourses, and
they are packed with insights and observations on tactics, leadership,
training, and discipline. Especially relevant to this study is Book 3,
Chapter 13, in which Machiavelli deals with the question of whether a
good commander with a feeble army or a good army with a poor commander
is most likely to be successful.
He quotes Caesar, who gave examples to
show that neither was worth much, and then goes on to give numerous additional examples of good armies that were successful despite being
poorly led, and also of outstanding commanders who achieved success with
Marshall, S.L.A. Commentary on Infantry Operations and Weapons Usage in
Korea, Winter of 1950-51.
Chevy Chase, M .: Operations Research
Office, The Johns Hopkins University, 1952.
Unit cohesion, pride in unit, especially company and regiment,
as factors in orderly withdrawal and recovery.
men firing than in World War II, with the chronic nonfirer the
There is nothing on quality of troops as a predictor of combat
Men Against Fire:
The Problem of Battle Command in Future War.
The theme of this analytic work is that it is the soldier who fights who
wins battles, that fighting means using one's weapons, that what is needed
for greater combat effectiveness is "more and better fire" (pp. 22-23).
Marshall stresses the need for realistic combat training; the soldier's
absolute need for physical support from other men in the unit; evidence
that no more than one man in four actually fires his weapon in combat (in
World War I1) almost regardless of time duraticn, Which men did fire
could not be predicted before combat,
Neither good discipline nor drill
perfection was an effective predictor (p. 60).
Some fighters were good
soldiers before battle, while some were not.
Combat seasoning consists of learning to do something better (e.g. fire a
rifle at an appropriate time and target).
Men do not become more willing,
less afraid, but rather, if anything, more afraid, after combat experience.
. Pork Chop Hill: The American Fighting Man in Action,
Sprig 953. New York: William Morrow, 1956.
A battle narrative ua&;'d on Marshall's after-combat interview methods.
His conclusions: the US *roops he observed in Korea were superior in
junior officer quality and initiative of enlisted men to any he had observed earlier (World War 1f); the policy of frequent rotation of troops
in and out of the combat zone was highly undesirable, as it robbed troops
of the chance to acquire combtt and deception skills, putting them at a
disadvantage to the enemy. Ma-shall reports on the personal characteristics
of 73 decorated soldiers whose superior courage and achievements he had
personally observed or established through interviews with witnesses: none
was an only child, and most were from families of three or more children;
most volunteered positive statements about their families and home life;
52 of the 73 spoke voluntarily with warm admiration of their fathers
The River and the Gauntlet.
William Morrow, 1953.
An account of the November 1950 retreat in Korea, focusing on a single
company of the 2d Infantry Division. This well-led, racially integrated
unit (60% white, 30% black, 10% attached Korean troops with mention also
of some Japanese-Americans) fought extremely well.
This is a detailed narrative account with little analysis. It includes
examples of the contagiousness of fear (pp. 47-48, 74-75). There is
nothing relevant to the relationship of precombat quality or capability
to combat performance.
Mason, Philip. A Matter of Honour: An Account of the Indian Army,
Officers and Ren. London: Jonathan Cape, 1974.
Contains much material, especially pp. 341-61, 449-53, on recruitment of
troops in British India, and the question of whether certain ethnic groups
mnadp especially good soldiers or whether effective training could make any
Moskos, Charles C., Jr. The American Enlisted Man: The Rank and File in
New York: Russell Sage Foundation, 1970.
Moskos describes US enlisted men's attitudes, showing that conventional
military attitudes and sources of motivation are apparently no longer
adequate. He suggests that the military has become increasingly isc'%ted
from the civilian population and from civilian attitudes and valu
Discussion of attitudes and behavior in Vietnam is included, but thefe is no
treatment of combat performance.
"How to Save the All-Volunteer Force."
fall 1980, pp. 74-89.
Thp Public Interest,
A very useful article analyzing the current 1ll-volunteer army and stressing
the need for an army that represents a cross-section of the country in
aptitude and educaticn. Moskos urges greater education benefits (GI Bill)
as the most useful incentives for enlistment by migh-aptitude people. He
also favors a "two-track" system, with short-term, lower-pay, high-educationincentive citizen soldiers, on the one hand, and long-term, higher-pay, career
soldiers, on the other.
Remarque, Erich Maria. All Quiet on the Western Front.
A.W. Wheen. Boston, Mass.: Little, Brown, 1928.
Like The Red Badge of Courage, a fictional classic that gives a realistic
picture of combat at the level of the individual soldier. Ajll Quiet provides
a good supplement to the World War I material presented in Baynes's Morale.
Remarque stresses the importance of training, discipline, and drill, not
only for their own impact on combat performance but for building the allimportant unit cohesion. The importance of keeping the same group of men
together is stressed.
Saxena, K.M.L. The Military Sysem of India, 1850-1900. New Delhi:
This work includes much material on the ethnic, class, and caste composition and structure of the Indian Armies in British India,
Senger und Etterlin, Frido von.
Neither Fear nor Hope.
E.P. Dutton, 1964.
regarded German memoir of World War I[, with good material on
strategy, and the relationship of political factors to military
this book makes only passing references to troop quality. There
references to declining troop quality in the last days of the
Stouffer, Samuel A., Arthur A. Lumsdaine, Marion Harper Luinsdaine, Robin
M. Williams, Jr., Brewster M. Smith, Irving L. Janis, Shirley A. Star,
and Leonard S. Cottrell, Jr. The American Soldier: Combat and Its
Studies in Social Psychology in World War I t,
Princeton, N.J.: Princeton University Press, 1949.
This work, and its three companion volumes, contain a wealth of quantified
and analyzed data on combat behavior. This volume is especially relevant
to the present study. One study it reports found that intelligience score,
level of education, mechanical aptitude score, and positive nrecombat
attitudes about combat all correlated strongly with good combat performance
The Art of War. Translated by Samuel B. Griffith.
Oxford University Press, 1963.
While this classic work may be regarded as folk wisdom, it does codify
enduring Chinese military principles. There is useful material on the
care of troops and means of motivating them, much of it tending to demonstrate
the longevity of universal p-iciples. This work also contains comment on
discipline, including Sun's Famous story of the beheading of the emperor's
Truscott, Lucian K.,
Lieutenant General Truscott's memoirs of World War II show the importance
of academic (e.g., tactical/strategic), physical (e.g., speed marching),
"and psychological (e.g., combat experience) training to combat performance.
Truscott shows the importance of integrating men with combat experience
with inexperienced men in training programs, thereby providing the knowledge gained through combat experience to training programs. He also
describes "realistic" training programs and stresses the importance of
combat rehearsals in assessing and adjusting training procedures (pp. 84,
Truscott claims that training must be continuous (pp. 85, 90, 352, 397,
456-57) and suggests that intensive training programs should be held,
when possible, just prior to combat (p. 360).
Truscott also shows how
morale, leadership, discipline, esprit de corps, and planning play essential
roles in determining the capability of the individual soldier and of the
Throughout the book, Truscott stresses the importance of the capability of
the individual soldier and shows how the capability of the individual often
reflects the combat effectiveness of the unit (pp. 97-98).
He also provides
specific examples of training correlating with combat effectiveness (see
pp. 81, 87, 115, 212, 214, 376, 882, 400-01, 415, 465, 474, 539-40).
Truscott also shows how education and social and national attitudes influence
not only basic troop quality, but also the ability to profit from training.
Truscott compares the national characteristics of the American, British,
and German soldier (pp. 555-56) and shows how these characteristics affect
For example, Truscott concludes that tha British
soldier is better at defense while the American soldier is better at offense.
Truscott also provides examples of inexperienced troops with a poor level of
training showing low levels of combat performance (pp. 83, 93, 178, 212).
Center of Military History.
The 442d Infantry Regiment is of interest as a crack unit composed of
highly motivated, well led, ethnically homogeneous troops that performed
in combat with great distinction. The regiment, made up of JapaneseAmericans, won four Presidential Unit Citations in World War II fighting
in Italy ano France, and is acknowledged by historians as a superb regiment,
probably the most decorated in the campaigns in which it participated.
should make a good candiddte for any study of elite units. This fact
sheet gives the basic data on the regiment.
Historical Division, Headquarters US Army Europe.
Military Studies, 1945-54:
Catalog and Index.
Guide to Foreign
Following World War II, a number of captured German general officers were
asked by the US Army Historical Division to write reports of their wartime
conmands for historical purposes.
Scattered through these reports is some
information on troop quality and capability. A historian on the US Army
Center of Military History staff has suggested that the report of General
Blumentritt, Chief of Staff of OB West and commander of Army Group Blumentritt, may be an especially good source for such material.
indexes the German generals' work.
US National Archives.
Captured German records of World War II.
A specialist on these records who was consulted about their relevance to
the present study states that there is some material on troop quality and
capability scattered through them, especially in records dealing with
There is data on quality deterioration late in the war, and
some material relating quality deterioration to operational problems.
INDIVIDUAL CAPABILITY AND GROUP PERFORMANCE, WITH
SPECIAL REFERENCE TO MAN/MACHINE SYSTEMS
The research psychologist who formed part of the HERO team for this
SCACE project was asked to prepare an overview of literature dealing with
the relationship between individual performance and group performance.
It was understood that, because of the nature of the project, the focus
should be on material relevant to a military environment and military tasks.
:t was further understood that the project was especially concerned with
the effect that the aptitude of the subjects, as measured by standardized
tests, might be expected to have on the level of group performance, and
that there was a special need to determine what differences might be found
between the performance of groups composed of individuals representing a
normal distribution of aptitudes (as measured by standardized tests) and
groups composed of predominantly low-aptitude individuals.
An initial assumption of this investigator was that the effects of
because combat performance is performance under
extreme stress, would be a significant area for investigation.
known to introduce factors that can be expected to affect group performance
stress upon performance,
Consultation with the COTR
differently from non-stress environments.
indicated, however, that it was not necessary to restrict the investigation
to performance under stress, especially since the COTR had already reviewed
much of this material.
The investigator then noted that group performance could be expected
to differ as a function of several other variables as well.
he called attention tc the following variables and their joint effects:
Some tasks require coordinated performance b a number of
individuals; others require isolation of carefully prepared operators;
still others require neither cooperation nor isolation.
Some groups are loosely organized and require no
a Group organization.
central task leader or emotional leader; other groups may be extremely
or may allocate functions in one of many different
- Group leadership.
Some task leaders also attempt to function as
emotional leaders; other distance themselves from that role.
The investigator believes that recent psychological literature shows
that the effectiveness and morale of groups is greatly dependent on the
match among these variables, as well as the talents and abilities of the
The following major compendia and journals in the social sciences were
reviewed for possibly relevant material:
* Journal of Applied Psychology
e Journal of Personality and Social Psychology
* Journal of Political and Military Sociology
e Sociology of Work and Occupations
* Personnel Psychology
m Advances in Experimental Social Psychology
s Handbook of Social Psychology (both editions)
* Handbook of Small Group Research
* Handbook of Group Leadership
A large number of texts, reference materials,
and library catalog materials
were also reviewed.
Nothing was found of particular relevance as a result of this search
that had not already been considered by the COTR.
A number of avenues of
investigation, suggested by other HERO team members, or the COTR, and appearing
to offer promise of relevant data, were not Droductive for a variety of reasons:
a Social psychologists in academic settings deal with extremely small
groups (compared to military units), and tend to see only gifted
# Those working in military settings have contributed important work,
already known to the COTR and incorporated in his work.
* Those working in industrial settings tend to deal with individuals
who are relatively competent. Those who are not competent do not
remain in the positions studied, given the play of the labor market.
* Training programs for the disadvantaged are alnost exclusively concerned
with individual skills.
Thus the investigator established that useful research in the area
mapped out for his work had been well covered by the COTR,
seemingly useful work, would not in fact be rearding.
and that other,
In a consultation
between the investigator, the COTR, and the HERO project coordinator,
investigator was asked to direct the focus of his investigation for the
reâ€¢nainder of the project to literature on the relationship between the
tested aptitude of the individual and his perforwmance in operating complex
to the relationship between aptitude and man/machine
As the best summary of the research on this question, arid one specifically
focussed on a military environment and the question of large numbers of lowaptitude personnel, the investigator has submitted the attached paper by Dr.
Earl Hunt and Dr. Marcy Lansman of the University of Washington.
has long been one oil the foremost contributors to studies in the field of
intelligence, and Dr.
Lansman has done much work in the human factors field.
COMMENTS ON THE CATEGORY IV PROBLEM
Earl Hunt and Marcy Lansman
The University of Washington
Upon the initiation of the all-volunteer force, concern was expressed
about the ability of the services to attract quality personnel.
A target of
20% Cateqory IV enlistees was established for the Army.
Early analyses suggested that this was not a problem, and that in fact only 11% of the Army
enlistees were in Category IV (Cooper, 1977).
It was subsequently found that
the test norms were in error, and that 45% of current enlistees fall into
this category (Holden,
The implications of this fact have been hotly
The extreme points of view seem to be that (a) the Category IV
classification is only a statement about reading, which is not relevant to
many Army tasks, or (b)
that the Army contains many decidedly subnormal
dividuals, who might well be on public assistance, or even institutionalized,
were they nut in the Army. We believe that neither view is justified.
this report we analyze the capabilities and weaknesses that may be expected
in Category IV enlistees.
The report focuses upon behavior in using equipment.
In preparing the report we have drawn primarily upon the general psychological
literature on the relation between intelligence and social and economic perfcrmance.
While a complete scholarly review has not been possible in the time
available, we believe that there is considerable consistency in this literature,
ard that it is applicable to the military situation.
The report begins by discussing some of the general findings concerning
The Armed Forces Qualification Test (AFQT) will be related to
the major dimensions of Intelligence, as cefincd in the psychological literature.
The next section deals specifically with Category IV individuals.
Here we will
consider the characteristic reactions of similar individuals in civilian
educational and occupational settings. The third section describes the sorts
of problems that Category IV individuals are likely to encounter when they deal
with military equipment.
to work situations.
Some remarks will be made about their general reaction
The final section of the report suggests possible responses
of the Army to the presence of large numbers of Category IV enlistees.
section also presents some topics for further research, and a brief list of
The Interpretation of Aptitude Test Scores
The definition of a Category IV person is that the enlistee has obtained
a score on the Armed Forces Qualification Test (AFQT) that falls within the
10th and 30th percentiles with respect to World War II enlistees. The AFQT is
test composed of subtests from the larger Armed Services
Vocational Aptitude Battery (ASVAB).
The AFQT score is obtained currently by
summing scores on a test of vocabulary, paragraph comprehension, arithNetic
reasoning (with the problems presented in words),
and speed of simple arithmetic
Statistical studies have shown that the AFQT correlates highly with
reading grade level.
Indeed, these correlations are so high that scores on the
AFQT could be substituted for scores on standard reading tests (Mathews,
grate the test.
To say that the AFQT "just measures reading" does not deniReading itself is important in a number of adult settings.
Military personnel must read such things as directiortorders of the day, and
equipment operating instructions in order to function in the services (Sticht,
et al., 1972).
Perhaps more importantly, reading ability is a generally accurate
predictor of the ability to deal with the spoken language.
Although there is
such a thing as "specific reading disability," for most individuals difficulty
in comprehending written material is indicative of difficulty in comprehending
The importance of this should be emphasized.
Although "learning to
read" is undoubtedly important, responding to low AFQT scores by sending people
to reading schools may miss the point. Given that a person has been exposed to
from eight to twelve years of pub.
lack of reading ability is
generally indicative of a more pervas~ve problem in linguistic comprehension.
Can one extrapolate from the AFQT score to something other than "verbal
comprehension"? To what extent can one say that a person in Category IV has
low intelligence? The answer to this question is more difficult. We will refer
to "verbal ability" to indicate the ability to deal with both the written and
This is part of intelligence, but only a part.
In our opinion,
intelligence itself is not a single characteristic of an individual, but is
rather an abstract tern that refers to the tendency of a number of mental competencies to be positively correlated.
One should think of intelligence as
analogically similar to athletic ability - which may be expressed in several
and is obviously composed of more basic factors
instead of thinking of
intelligence as analagous to height or blood pressure.
The question "Is a
person intelligent enough for this job?" is almost always too simplistic.
Instead the question should be "Does the person have,
or can the person acquire,
the mental competencies necessary for a particular job?"
one has a reasonable measure of verbal ability.
that might have been measured,
Given the AFQT score,
What are the other competencies
and what information does the AFQT carry about
Although the exact nature of the underlying dimensions of intelligence is
a matter of considerable controversy amongst psychologists,
ment on certain facts.
there is broad agree-
Two broad domains of cognitive skill can be identified.
One is the ability to deal with verbally presented material, either in speech or
writing. The second is the ability to deal with visual-spatial problems, such
as might be called upon in recognizing that one piece of a machine fitted against
another in a particular way.
Within the domain of verbal ability a further dis-
tinction is usually drawn between verbal comprehension - the ability to understand
the material presented - and reasoning - the ability to draw conclusions from
that information and to generalize conclusions from one situation to another.
Reasoning ability is not entirely restricted to the verbal domain, but it is
highly correlated with verbal comprehension,
especially in young adults.
if one knows an enlistee's verbal comprehension ability, a quite accurate estinmate
of reasoning ability can be made.
low comprehension ability is a
good indicator of low reasoning ability.
Prediction is much less accurate across the verbal and spatial domains.
The correlation between word knowledge
.a good test of verbal comprehension)
a spatial reasoning test in the ASVAB is only .32 (Fruchter and Lee, 1977).
Thus while one could guess from a very low verbal score that spatial reasoning
was "below average",
not be accurate.
because the two are positively correlated, one's guess might
A guess of "as low as the verbal score" would definitely not
On statistical grounds alone, one would expect a person with a
low verbal score to have a somewhat higher spatial score.
A third domain of cognitive skills can be called, loosely, "psychomotor
abilities." These are the abilities involved in real time co-ordination of
perception and motor output.
is difficult to summarize this field succinctly,
because it covers a great many tasks, ranging from the simple co-ordination
required in, say, pointing a rifle, to the complex combination of memory, attention, perception,
and motor skills needed to pilot a helicopter.
differences in psychomotor abilities are large,
but appear to be highly specific
to the particular acts of co-ordination involved.
Thus performance on tasks
involving gross motor movements of arm or leg may not predict perfornance on tasks
involving finger dexterity.
the correlations between psychomotor
performance and performance on tests of either verbal or spatial ability are
at best modest.
Correlations between verbel ability
tasks will range from 0 to .4,
measures and psychomotor
depending on the particular task involved.
relations can be expected to be slightly higher between psychomotor performance
and spatial ability tasks.
These facts pose a considerable problem for personnel
On logical grounds alone, one can assume that psychomotor skills are
involved in machinery operation.
The specific nature of these skills, however,
hard to talk about predicting who will be a "generally good machinery
One has to specify just what machinery will be used,
will not be possible to estimate the persun's skill
and often it
in machinery use until
the person has been trained to use the machinery.
Characteristics of Category IV Enlistees
The definition of a Category IV individual is somewhat variable, depending
u)on the lower cutoff limits that were in use
at the time of the enlistment.
In order to relate the Category IV classification to classifications used more
generally outside the military, we ;hall assume that we are dealing with individuals who would score between 80 and 90 on a measure of verbal intelligence.
Such individuals can accurately be characterized as having "low verbal aptitude,"
is a mistake to regard them as high grade mental retardates.
retardates would have scores in the 65-75 range, and would undoubtedly present
much greater training and supervision problems than do the Category IV enlistees.)
What is the general behavior of such individuals? A low AFQT score suggests
that the enlistee has,
for the most part, been unsuccessful in school,
though a high school certificate may have been achieved.
The failure to learn
to read suggests strongly that the enlistee has not in the past, and will not
in the future, absorb material well in a formal classroom setting. Our best
guess is that the same enlistee wil)
be relatively stronger in spatial and vis-
ualization than in language skills, although still somewhat below average.
have very little information about the person's psychomotor skills.
Individuals such as this have a great deal of trouble in formal educational
This is hardly surprising.
the public schools,
Having already had great difficulty with
the person is not a good bet to do well
Perhaps because of their low reasoning skills, Category IV in-
dividuals are likely to have great difficulty in grasping general principles,
Median Scores on the AriV General Classification Test for Enlistees from Several
Occupations (Data Gathered from the World War II Mobilization Simple)
85 - 89
Laundry Machine Operator
Groundman, Telephone, Telegraph, or Power
either when taught by expicit discussion or by example.
appears that one of the most efficient ways to teach general principles is to
rely on formal,
verbal argument - precisely the sort of instructional
that is hard for a person with low verbal aptitude.
The civilian experience also suggests that the low-aptitude person takel
longer to teach.
This is at least In part because the economical "verbal"
mode of instruction will not work.
The knowledge that the low-aptitude person
takes away from training is highly specialized to the precise content of that
Thus training nust be specific to the job the person is going to do.
it must be one-on-one,
hands-on training in which the person is
shown what to do,
not told what to do.
Given these qualifications, though, the
low-aptitude individual is capable of operating in a variety of economic roles.
People who do very poorly in school are often capable of achieving useful
economic roles, provided that they find the right situation.
The ideal niche
for a low-aptitude person is one in which problems are predictable (ano hence
the individuals can be trained in advance to react to them) and in which the
general environment is stable.
One of the striking characteristics of a lowaptitude person is that behaviors that have been learned in one situation do
not readily generalize t,- other situations that seem only superficially dissimilar.
A less abstract idea of what the Category IV is capable of can be obtained
by considering the sorts of jobs that Category IV individuals hold in civilian
Table 1 shows a selected list of jobs that were held, prior to enlistment,
by "Category IV" individuals in the original World War II reference population.
With only slight updating we believe that it would be accurate today.
the Table also shows selected jobs held by
individuals who fell into
A comparison of the Jobs shows that in a competitive society,
Category IV individuals hold unskilled or slightly skilled jobs.
do not operate complex machinery, nor do they hold jobs in situations in which
one must make decisions about what to do.
require operation of fairly simple machinery.
that the jobs held do
On the other hand,
of these jobs require extensive verbal communication.
An analysis based on "jobs held" understates the ability of low-aptitude
In an economically competitive society,
these individuals may not be
able to compete for positions that they could occupy
if they were employed.
Table 2 shows the Department of Labor's estimates of the minimum qualifying
scores for a variety of Jobs.
(The scores in this table are based on a General
Aptitude Test Battery composite similar to the AFQT.)
There are interesting
Mlnimum General Intelligence Score Required for Success in Several
Occupations According to the General Aptitude Test Battery Norm
Heavy Equipment Operator
Parking Enforcement Officer
Key Punch Operator
Licensed Practical Nurse
apparent inconsistencies between Table 1 and Tele 2.
In several cases the
median scores obtained by persons in an occupat on are considerably above the
minimum scores required to perform in the same occupation.
The truth Probably lies somewhere between these extremes.
competitive factors in the labor force, the civilian economy almost certainly
underutilizes low-aptitude individuals. This is important because it suggests
that our "coamon sense" observations about the sort of jobs People do will
lead us to underestimate the capabilities of people similar to Category IV
On the other hand, the GATB test scores indicate what a sinqle
individual might do in a normal work setting.
From the empioyer's point of
view, a work force consisting of, say, 40% minimally qualified individuals
is quite different from a work force that contains a few minimally qualified
Unfortunately, the tradeoff between these factors is not known,
is unlikely to be obtained from studies of the civilian economy.
Use of Equipment
Is the equipment found in the Army likely to pose a problem for the
Category IV individual,
and if so where will this problem lie and what can be
In answerinq these questions it is important to distinguish
done about it?
between training, operation,
The three phases of equipment
use appear to require considerably different cognitive skills.
Training is a form of education,
and education is hard on a Category
It will take longer to train Category IV soldiersto operate equip-
When they are trained, they will not generalize readily from training to
Thus even when a skill is mastered in training, the Category
IV soldier may not realize that it is applicable in a superficially quite difh
The highly efficient lecture mode of instruction will be difficult for
the Category IV soldier, even when lectures make heavy use of audio-visual
procedures and demonstrations, Audio-visual procedures may require Just as
much imagination as dealing with text, especially if they are schematized.
training films are idealizations that require the viewer to imagine himself
being in the situation. Equally important, Category IV individuals have not
learned the skills necessary to learn from lectures, film strips, or audio-visual
presentations. There is no particular reason to believe that the Army can
can succeed in teaching these skills where the public school system failed.
We are similarly pessimistic abo.t'tOrwposals to "teach the Category IV's to
read." The probability of significantly imwproving reading skills in the
(This observation, of course, should be tempered
time available is small.
for anyone who has had-little exposure to English.)
The answer to the training problem appears to be simple, direct, and
expensive. Category IV individuals learn best by doing. They need closely
supervised experience with the specific tasks that they are going to do in
the field. If possible, they should be trained by the same people who supervise them in the field. The training can be expected to go slowly, and the
trainer will have to be extremely alert to the actual progress of the student.
We shall return to this basic point several times. The available
psychological literature, although seldom directly relevant to the Category IV
problem, contains a great deal of tangentially relevant information. All of
this information is consistent in indicating that low-aptitude individuals do
not generalize easily from training situations. Thus training must be as much
like the field situation as possible.
Operation. The typical finding is that Category IV individuals can operate
equipment providing that it is not "too complex." But what does complexity
mean? For our purposes, one can distinguish between complexity due to the
fact that many things must be done in a predictable sequence, and complexity
because there are many decision points. Changing a tire is complex in the
former sense, while driving in traffic is complex in the latter.
Low-aptitude individuals can be trained to handle detailed but predictable
Indeed, mental retardates (who are considerably below the "Category IV"
level in general mental aptitude) have been trained to operate reasonably deNaturally, any equipment operation involves
tailed but predictable equipment
dealing with some contingencies. The Category IV person can handle these,
provided that the contingencies that occur can be specified in advance. To
illustrate, people with low general aptitude obtain Jobs as janitors. These
jobs require numerous decisions about what equipment to use, but the distinctions
are usually clear cut.
The Category IV soldier is likely to fail in equipment operation when an
unexpected contingency occurs, or when situations change in such a way that
previous specific training is no longer appropriate.
The low-aptitude person
can t'4crate little change in the superficial aspects of a work situation.
changes in supervisory personnel would be likely to be more dis-
ruptive to Category IV than to cognitively more competent individuals, even
though such changes s;iould make little,
eration per se. For similar reasons,
if any, difference in equipment opa change in assignment,
even though not
accompanied by a change in duties (e.g. a transfer from onp infantry company
to another) might be more disruptive to the lowr level person.
equipment will also be disruptive. When new equipment is introduced into a
an inevitable retraining period.
Normally, knowledge of the
principles used governing the operation of the old equipment will help in
understanding the new equipment.
This will be less the case with Category IV
This section is well summarized by the remiarks of an Army Armor Corps
captain whom we interviewed while preparing this report.
He pointed out that
preparing the power pack of a tank for removal is a complex but predictable
task that requires the execution of a number of steps in a particular sequence.
Bdsed on his experience,
he felt Category IV soldiers could learn to do this
Repairing a sight mount "in the field" is a simpler but less predictable
The soldier must find whatever is at hand that can hold the sight in
place, install it,
and recalibrate the weapon.
insights into the purpose of equipment,
of equipment fit together.
Such improvisation requires
rather than into the way particular pieces
These insights are likely to be hard to develop in the
Category IV soldier.
Clearly the key to utilizing the Category IV soldier is to make the situation
as predictable as possible.
Military operations are, by their nature, often
Thus in a changeable situation it will be extremely important
that the Category IV soldier be closely supervised, and supervised by someone
with whom he is familiar, so that the supervisor can act as decision maker,
filter out the unfamiliar, and present the task to the soldier as being one on
which he is already trained,
for the combat arms,
Such a requirement poses a considerable problem
because casualties among noncommissioned officers (NCOs)
can be predicted to be extremely disruptive.
If the private soldiers are of
low aptitude, one can neither count on finding leaders to replace the lost
setlgeants from within the unit, nor can one easily transfer new sergeants into
- - .
Maintenance and repair lie somewhere between training and
Some aspects of maintenance are routine and highly
such as changing the oil in an engine.
even of a detailed nature,
can probably be performed
by Category IV soldiers. Maintenance that requires fault diagnosis Is likely
to prove difficult, because this sort of task requires logical reasoning, an
ability that is likely to be weak in a person falling into Category IV.
maintenance and repair tasks involve the following of relatively abstract inBoth ways
structions, presented either in writing or by schematized diagrams.
of presenting repair instructions are likely to be hard for a person with low
Category IV soldiers involved in maintenance and repair will require a
large amount of supervision.
Our feeling is that the ol)tiral repair shop con-
taining a large number of Category IV
individuals should be organized around
highly specialized work stations. A supervisor would determine what needed to
be done for a specific piece of equipment, and would move that equipment, step
The shop atmosphere should be kept
by step, from one work station to the next.
as stable as possible.
Although our charge is to discuss the use of equipment, we
A General Comment.
would like to raise a "sociological" point.
Most of the present information
concerning low-aptitude workers is based on the performance of isolated individuals working with cognitively more competent colleagues.
edly benefit from informal,
supportive social networks.
Such people undoubt-
person probably needs these networks more than his or her more talented colleagues.
Very little is known about the effects of having a work force composed predominantlyof Category IVs.
(Rather more is known about the problems encountered
in "sheltered workshops," but these institutions generally deal with people very
The following speculative remarks
considerably below the Category IV level.)
1) Close supervision will be essential.
The supervisor must act as a
buffer between the individual and a potentially confusing world.
terms, the burden is once again on the noncommissioned officer.
For this reason, It is important that first-line supervision be stable.
Frequent rotation of NCOs would be a serious problem.
In combat situations NCO
casualties will not be easy to replace.
If half the work force are Category IVs,
then half are not.
category personnel will preempt informal leadership roles.
and motivation of these individuals becomes important.
Thus the morale
Their example will
be a good or bad example?
the pervasive supervision appropriate for Category
IV soldiers may hurt the morale of more competent individuals in the same unit.
To illustrate, the "assembly line" operation suggested for a repair shop staffed
largely by Category IV personnel is known to be distasteful to more competent
individuals; witness the current move toward craftwork and personalized completion of jobs in many industries.
This could present a still further problem for
If an appropriately stable situation can be maintained, Category IV
soldiers will find it
agreeable ard will not be motivated to leave the service
either for change or for potential career advancement.
pect career advancement within the service.
Neither will they ex-
Thus longer enlistments may be pos-
sible at the lower ranks in order to capitalize on a considerable training
Policies in Dealing with Category IV Individuals
1. If possible, training should be accomplished within the operating units.
Training should be on the equipment used in the field, and should be "hands
Allowance should be made for the length of time required.
could be as much as 50% greater than the normal length of training.
The noncommissioned officers who deal with Category IV personnel are crucial.
They will be required to give individualized training, to check frequently to
make sure that apparently simple tasks really have been learned, and to tailor
training to the capabilities of the individual soldier.
Probably the most im-
portant single thing that the Army can do to utilize Category IV personnel is
to provide adequately trained and motivated NCOs.
have a high degree of technical skill,
teaching and leadership situations.
These NCOs will not have to
but will have to deal with difficult
The operating environment should be stable.
Once trained, the Category IV
soldier should be kept on the same Job, and in the same unit.
personnel should be stable.
As retraining will be long,
should be given to the utility of introducing new equipment into a unit.
new equipment is introduced,
careful preparation for the changeover will be
Repair procedures should rely on exhange of parts (which assumes an adequate
logistical system) and routine operations.
Little reliance can be placed on the
ability of field personnel to improvise.
The Category IV soldier should be trained to do one highly specific job.
Multiple personnel assignments, such as are routinely used in some military
situations (e.g. the submarine service) will not be feasible.
"6. In evaluating the readiness of a combat unit consisting of large numbers of
Category IV personnel,
consideration should be given to unit performance when
NCO and junior officer casualties are simulated.
Studies of Job performance should not be based on a narrow definition of
the work required.
The total adjustment of the soldier to the Army must be
This is particularly important in the case of a Category IV person,
who may be less able to divorce work and general social adjustment.
the Category IV soldier is assigned to a nonverbal job, the soldier still has
to deal with a verbal Army.
There is a great deal that we do not know.
psychological research focuses either on individuals with superior aptitude
(typically college students) or upon mental reta,-dates, whose performance is
much below that of low-aptitude individuals.
As was pointed out, studies of
how low-aptitude persons function in equipment-oriented jobs are not likely to
be conducted in the civilian work force, for the simple reason that civilian
employers have more economic labor forces available to them.
If the Army were
to plunge ahead with an intensive training program for Category IV soldiers,
it could be an extremely expensive one.
training be evaluated carefully.
It is important that such
It would also be desirabl
to extend the in-
itial categorization of soldiers beyond the realtiVEly crude categorization
system based on the AFQT.
The following suggestions are offered.
possIble to develop tests in the psychomotor field that would
although they might not predict training?
been tried beWore, without notable success.
The new microcomputer technology
may make the construction of appropriate psychomotor tests feasible, but this
contenti3n has not been proven.
Most of our current data concerning the relation between tests, and between
test and work performance,
is based upon studies of the entire range of capa-
bilities in the population.
Studies of the relationship between test and work
performance within the Category IV population itself should be conducted.
of this data must already be available to the Army, through records of ASVAB
scores and work records.
Studies of the social aspects of the work situation should be instituted.
Of particular concern are such questions as (a)
the trade-off between unit
performance and the percentage of Category IV individuals in the unit, (b)
appropriateness of special training fr
officers and NCOs who deal with such
the effect of ,trurturig job situations in various ways
both upon the Category IV soldier and upon .ther soldiers in the same unit.
Suggested Further Readings
There is really very little that we have found that is directly relevant.
Most of the psychological
lower range of ability.
literature deals with individuals at a higher or
This is certainly true of review or textbook articles
on "intelligence," for these are heavily weighted toward studies in educational
settings, and usually ot college students,
people who do not enlist in the Army.
retardates, or the elderly - all the
The following three general references
are most helpful.
A good overview of intelligence testing in general can be found in the
first section of the book
Information Processing, and Analogical Reasoning.
The first part of this book contains a good description of various
approaches to the definition of intelligence.
The remainder of the work is
concerned with a specific research project and is of almost no relevance to
the question at hand.