Playful agents, inexorable process - PDF document

Playful agents, inexorable process PLAYFUL AGENTS, INEXORABLE PROCESS:ELEMENTS OF A COHERENT THEORY OF ITERATIONIN ANTHROPOLOGICAL SIMULATIONtion. It makes two basic arguments:1) that iterations must be bound by the rhythm of inexorable physical proc-2) that within the limits of that rhythm, agents must be free to make deci-far. In these traditional models, agent activities and external processes aregenerally resolved in an arbitrary order. As we will see, there are two majorpredictably. First, such a free-form system makes it much easier for a simula-Simulations in Anthropology, from the very classic, such as WOBST’s (1998) simu-lation of !Kung San demography, have generally taken an approach toogy, no systematic discussion of the problem of iteration. Each of the three,excellent, above named models is essentially a population simulation, andand why an arbitrary length of one solar year, or any other arbitrary length, Human agents, as Charles TAYLOR (1993) argues, are access to a limited portion of that world. Furthermore, they organise theirlocation can be seen as a flow, or quantity of information over a given periodhypothesis testing about at least some aspects of human behaviour and or-time-critical imperatives which are consistent with those of human experi-From a human perspective, time (and therefore access to space) is punc-tuated by a number of inexorable physical processes, some of which are in-ternal to humans (for example the female reproductive cycles, both longInformation is a crucial raw material of human agency. Information isthe inexorable processes which punctuate and organise the human experi-fore lies in the selection of the particular inexorable process whose rhythms experience of time limits its access to infor- Playful agents, inexorable processWithin the bounds of the selected inexorable process, between the beatsof this systemic rhythm, agents must be free to engage in the constant nego-tiation, or play, which characterises human social processes. This will be-In the phase-based model, operations are resolved in a particular, oftenarbitrary order. For example, a phase based simulation might, within an it-eration, first check all agents for mortality, then check all agents for repro-feasts is especially critical. From a human agenttion, or the social construction of these events, however, is highly negotiable. an iteration, in relation to any other type of event, forlinear phase based system, while it can incorporate some uncertainty, tendsrelated to event scheduling to exert a greater influence on agent decision-available from the author. In order to maintain an anthropological focus, the approximately 28 days. The first noticeable benefit of this approach is that its mating activity. This allows for real-s results to emerge more freely, es-Before I can discuss what the agents do and why, I must describe thes awareness of, and interactionswith, a much more complex and comprehensive physical reality has beendeveloped in another module of the simulation (COSTOPOULOS 1999, 2001).is underway. Still, mere awareness of as opposed to access to other agents only insofar as they are sufficiently near each other.At the heart of the Agent social cognition system is a list of constantlyThe priorities vary in urgency and the relationships vary in intensity,agent priorities are in the form of drives, for example the mating priority.sult of action by other agents. For example, offspring have a care priority Playful agents, inexorable processwhich they are going to dedicate to the pursuit of their top priority.bidding process begins anew. When the maximum number of impulses isiteration. At the moment, there are three events in the simulation modelwhich are independent of agent control, can intervene unpredictably, andAt the start of each iteration during which it is pregnant, a female agentdetermines whether there will be a termination of pregnancy. The probabil-birth increases. If the pregnancy is terminated too early, the odds of live birthare very low to none. If there is a normal termination of the pregnancy, theautomatically take over and give birth. The births are therefore scheduled local group, thereby completely modifying their plans and behaviour.In this simulation model, episodes of illness are the result of the inter-tentially self-destructive behaviours and other threats. Each threat can havepreferences and tolerances for age and sex of potential victims. For example,males between the ages of 8 and 12 might be more likely than others to falland attack victims in the population which correspond to its preferred pro-s char-independently of agent activities and planning, and are the result of oppor- perception of the threats and interpretation of thesebehaviour, as well as the characteristics of individual threats and agents.cal process, during which agents can order priorities, evaluate urgency, and Playful agents, inexorable processOSTOPOULOSOSTOPOULOS A. 1999, Modeling and Simulation for Anthropological Archaeologydissertation held at Oulu University, Laboratory of Archaeology.OSTOPOULOS A. 2001, Evaluating the Impact of Increasing Memory on Agent Behaviour:Adaptive patterns in an agent-based simulation of subsistence, , 4, 4 (http://www.soc.surrey.ac.uk/JASS/4/4/ D.W. 1998, Kinship based demographic simulation of societal processes, 1, 1, (http://www.soc.surrey.ac.uk/JASSS/1/1/1.html).AYLOR, in C. G, Cambridge, Cambridge University Press. T.M. 1992, Dellplain Latin American Geography Series 28, Boulder,Westview Press.OBST H.M. 1974, Boundary conditions for paleolithic social systems: A simulation ap-, 39, 147-178.ABSTRACTtion of events in agent-based simulation for Anthropology. It is argued that an alternative A. Costopoulos266