I__. - International Military Testing Association

'L'KADLNC; OE'k' PEKFOKMANCE, TKAlNLNG, AND EQULPMENT
FACTOHS 'I'0 ACHLfiVE SIMLI,AK PEKFOKMANCE
Janet J. Turnaqe, university of Central Florida
Robert S. Kennedy, Essex Corporation
Marshall 8. Jones, Pennsylvania State University
INTRODUCTlON
Military systems performance is generally the joint outcome of the human
interacting with the machine. It is convenient to think oE this outcome in
terms of causal models, where the elements that determine or drive systems
performance may be relegated to equipment characteristics, training variables, .
and individual capabilities. We suggest that an appropriate starting place
for such causal analyses is to select a specific level of desired operational
or systems perEormance beforehand. We call this device level Isoperformance.
Then one can employ the different potential predictors of this outcome in an
Isoperformance model. The way the model works is to select each variable as a
potential predictor and then submit it to a trade-off methodology whereby each
variable is compared in light of total operational proficiency desired.
Examples of operational proficiency might be: (1) escape from an aircraft
water crash within 60 seconds, (2) completion of a forced march carrying a
36)-pound pack for 20 miles within 6 hours, (3) an 80% carrier landing board
rate, or (4) control of 20 aircraft in the same airspace simultaneously.
There are three meanings of the term “Isoperformance.” The first is a
conceptual approach to human factoring. Second, the term may describe a
curve, plotted against training time on the abscissa and aptitude on the
ordinate. Third, Isoperformance is a specific interactive computer program.
In this paper, we shall describe each of these features, in turn, and will
present an illustration of one type of application.
But first, let us more Eirmly specify the premise of Isoperformance. The
premise is that the same (Iso) total systems efficiency (performance) is a
function oE trade-ofEs between personnel, training, and equipment. To achieve
this state of affairs, the Isoperformance model is intended to:
(1) Make estimates of training outcomes for different categories of
personnel;
(2) Check internal consistency of estimates:
(3) Compare estimates to known relations from human engineering,
personnel, and training:
(4) Counsel how to change “wrong” estimates:
(5) Output Isoperformance curves; and
(6) Leave a hard- copy audit trai 1.
Isoperformance as a Conceptual Approach to Human Factoring
Isoperformance was inspired by a long history of involvement in human
engineer inq research, development , test, and evaluation. For example,
military speci.fications and standards Eorm the basis for numerous systems
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