Parameter values and functional dependences for the six models of object clustering behavior.

The code in curly brackets indicates, for each model, whether inter-individual variability, temporal correlation, picking up inhibition by or deposition stimulation by occur () or not (). The six models only differ by the functional dependences of the probability that an ant picks up an encountered object on the perceived density , and of the survival probability that a loaded ant carries the object longer than time on (or and , where is the ant’s activity level, when inter-individual variability is accounted for). For models 3 and 4, the activity levels are distributed according to an inverse gaussian distribution: . For models 5 and 6, temporal correlation is significant: decreases as the opposite of the derivative of a Malkmus transmittivity function with , a choice that is inspired by the physics of gaseous radiation [71] where distinct absorption rates at different frequencies lead to non-exponential spectrally integrated extinctions. In all six models, is deduced from the deposition mean free time according to , the walking speed is and the U-turn rate is with .