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4.4.3 Mitigating Measures

The measures that should be taken for this purpose are quite general and maybe best
understood by the community of simulators.
• One needs to check ones’ code thoroughly—see Galán et al. (2017)for areview
of techniques.
• One needs to be precise about the code and its documentation—the code should
be made publically available.
• Be clear as to the nature and scope of the hypotheses established.
• A very thorough sensitivity check, trying various versions with extra noise added
etc.
• It is good practice to illustrate the simulation so that the readers understand its
key behaviours but then follow this with a series of attempted refutations of the
hypotheses about its behaviour to show its robustness.
• Be very careful about not claiming that this says anything about the observed
world.

4.5 Description

4.5.1 Motivation

An important, but currently under-appreciated, activity in science is that of descrip-
tion. Charles Darwin spent a long time sketching and describing the finches he
observed on his travels aboard the HMS Beagle. These descriptions and sketches
were not measurements or recordings in any direct sense, since he was already
selecting from what he perceived and only recording an abstraction of what he
thought of as relevant. Later on, these were used to illustrate and establish his
theoretical abstraction—his theory of evolution of species by natural selection.
One can describe things using natural language or pictures, but these are
inadequate for dynamic and complex phenomena, where the essence of what is
being described is how several mechanisms might relate over time. An agent-based
simulation framework allows for a direct representation (one agent for one actor)
without theoretical restrictions. It allows for dynamic situations as well as complex
sets of entities and interactions to be represented (as needed). This can make it an
ideal complement to scenario development because it ensures consistency between
all the elements and the outcomes. It is also a good base for future generalisations
when the author can access a set of such descriptive simulations.

Definition
A description (using a simulation) is an attempt to partially represent what is important of
a specific observed case (or small set of closely related cases).