Page 261 - Socially Intelligent Agents Creating Relationships with Computers and Robots
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244                                            Socially Intelligent Agents

                               The unbounded formulation of such an economical problem has long been
                             the central concern of classic game theory which has produced a number of
                             models of social choice. For this reason game theory models have become
                             strong candidates for models of social agents. Surprisingly, such apparently
                             simple games can be used to conceptualize a variety of synthetic, meaningful
                             and formal prototypical context as games. Therefore, such models can be used
                             to design and engineer multi-agent systems as well as analyze the behaviour of
                             the resulting social artifact using the logical tools of the models. However, the
                             underlying unbounded assumptions of classic game theory is problematic for
                             the design of computational systems [2].
                               Artificial Intelligence (AI) on the other hand has long considered models of
                             the relationship between knowledge, computation and the quality of solution
                             (henceforth referred to as the K-C-Q relationship) [7]. AI has shown that there
                             exists a hierarchy of tradeoffs between K, C and Q, with models that achieve
                             perfect optimal results (like game theory models) but at the cost of requiring
                             omniscience and unbounded agents, to models that sacrifice optimality of Q
                             for a more realistic set of requirements over K and C [12]. Different agent
                             architectures are then entailed from different K-C-Q relationship theories.
                               In the next two sections two such computational models of negotiation are
                             proposed, one deductive and the other agent-based simulation, that can be an-
                             alyzed as two different games. The aim of these models has been to attempt to
                             address some of the computational and knowledge problems mentioned above.
                             In particular, in the first model the types of problems of interest is when K is
                             limited because agents have at best imperfect and at worst no knowledge of the
                             others’ utility functions. The best an agent can do is to reason with imperfect
                             knowledge by forming approximations of others’ utilities. In the second model
                             the knowledge problem is even more extensive because agents in addition are
                             assumed to have an incomplete knowledge of their own utility functions.

                             2.     A Bargaining Game
                               In this model there are two players (  and  ) representing one consumer
                             and one producer of a service or a good. The goal of the two agents is to
                             negotiate an outcome      ,where   is the set of possible contracts describing
                             multi-dimensional goods/services such as the price of the service, the time at
                             which it is required, the quality of the delivered service and the penalty to be
                             paid for reneging on the agreement. If they reach an agreement, then they
                             each receive a payoff dictated by their utility function, defined as
                                                  . If the agents fail to reach any deal, they each receive a
                             conflict payoff  . However, from the set  , only a subset of outcomes are
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