  Sugarscape is a well known and influential Agent Based Social Simulation
(ABSS). Various parts of Sugarscape are supplied as examples in almost all
Agent Based Model (ABM) toolkits. It has been used for demonstrating the
applicability of different approaches to ABM. However a lack of agreement on
the precise definition of the rules within Sugarscape has curtailed its
usefulness. We provide a formal specification of Sugarscape using the Z
specification language. This demonstrates the ability of formal specification
to capture the definition of an ABM in a precise manner. It shows that formal
specifications could be used as an approach to tackle the replication problem
in the field of ABM. It also provides the first clear interpretation of
Sugarscape identifying areas where information is missing and/or ambiguous.
This enables researchers to make proper comparisons between different
implementations of this model.
