I__. - International Military Testing Association

e different than their current distribution. Since most Army systems take 5- 10
years to develop, the capability to estimate the future distribution of key personnel
characteristics is a critical prerequisite for describing the soldiers who are likely to
be available .to man the system.
Estimating the future distributions of these aptitudes is not simple since these
distributions are impacted by a number of factors. First, the distributions are
impacted by the cutoffs that the Army sets for these aptitude measures. These
cutoffs eliminate soldiers who score below the cutoffs both from accessions and
from distributions of the aptitudes at higher paygrades. However, the cutoffs are
not the only factors determining these distributions. The distributions are also
impacted by the distribution of the aptitudes in different subpopulations of the
general population at a particular point in time, the propensity of those
subpopulations to enlist at various aptitude levels, and the rates (e.g.. reenlistment
rates) with which the subpopulations transition through the Army personnel
system.
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Question 2: Can the svstem be operated and maintained within available
mannower. personnel, and training resource constraints?
This question seeks to assess the “personnel affordability” of the new system. The
resource capabilities of the Army are limited. The total end strength of the Army is
fixed annually by Congress. The Army’s capability to recruit high quality personnel
is restricted by the recruiting budget. To effectively deal with these resource
limitations, the Army must set constraints for critical resources such as personnel.
During the acquisition process, resource requirements for the new system must be
established and compared with the constraints. If the requirements do not exceed
the constrainls, the system is affordable; otherwise, it is not. Manpower constraints
describe the maximum number of people who will be available to man the new
system. Personnel constraints describe: (a) expected cutoff values for key
characteristics such as aptitude, and (b) the expected distribution of these
characteristics above the cutoff.
APPROACH FOR ASSESSING APTITUDE IMPACTS ON SYSTEM PERFORMANCE
The relationship between aptitudes and system performance is not a direct one.
Aptitudes impact the performance of the tasks required to operate or maintain the
system. Performance on these individual tasks determines overall system
performance. Assessing the relationships between the performance of individual
system tasks and system performance requires consideration of the complex causal
and sequential relationships among tasks. Task performance will vary as a function
of the conditions under which the tasks will be performed. These conditions will
vary across time and across scenarios.
Measures of Svstem Performance,. A number of metrics can be used to quantify
system performance. Typically, two types of measures are developed: operational
effectiveness (e.g. mission performance time or success) and system availability
(e.g. system reliability, availability, or maintainability).
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