In most current synthetic environments, the individual entities in the simulation will execute the same task in the same way, ignoring differences between individuals, and even the variability of a given individual over time. In the real world, this is not the case. The choice of strategies and the ordering of sub-strategies will vary across individuals and will vary for a given individual across time. When such variance is not included in a model, it makes adversaries, allies, and neutral personnel too predictable because they will always do the same thing at the same time in the same way. Recent thinking recognizes the inherent variability of humans (i.e. differences in cognition and physiology from one individual to the next), and the necessity of modelling this to improve the realism of synthetic forces.
The Improved Human Behaviour Representation (IHBR) project (UK Ministry of Defence) addresses this shortcoming. Using CoJACK™, realistic human variation is generated in a psychologically-grounded and therefore principled manner. This is a major step forward relative to the ad hoc approaches of the past. CoJACK predicts variation in decision-making time as well as errors that can occur due to moderating factors (e.g. fatigue). Situation awareness is also explicitly represented and logged, allowing analysis of the extent to which unexpected behaviour resulted from deficiencies in situation awareness.