abstract

If accurate communication provides benefit to both participants in a communicative event, at least some of the time, the sender will motivated to produce signals that the receiver is likely to interpret accurately. and the receiver will be motivated to interpret a signal as the meaning it is most often used to express. In a population where this is true, a conventional communication system can result from a process of of negotiation, as the agents alternate between contributing to, and conforming with, the emerging system.

A conventional communication system could be based on a simple table in which each meaning to be conveyed is associated with a unique signal. However as the number of meanings increases, the system becomes increasingly difficult to learn and to use.

If the set of meaning is large, the agents probably don’t use a distinct internal representation for each of them. Their representations are most likely constructed from a relatively small number of component types. The interpretation of an internal representation depends on the specific components use to construct it, and how they are configured.

When an agent expresses a meaning, it will, in general, use aspects of the structure of its representation of the meaning in its derivation of the structure of the signal used to express that meaning. The receiver’s interpretation of the signal will make use of the signal’s structure to derive a representation of the meaning it conveys. The derivations performed by the sender and receiver therefore constitute implicit analyses of the relations between the structures of meanings and signals.

The structural derivations performed by the sender and the receiver might have no relation to one another, except that they both involve the same signal, and, if the agents are are lucky, equivalent meanings.

For them to achieve better than chance accuracy, I assume that the members of a population obey a set of negotiated conventions regarding possible derivational relationships between the structures of signals and meanings. These conventions can emerge if senders perform their derivations of signals while considering how receivers might interpret them, and if receivers derive their interpretations of signals while considering how they might have been constructed by senders. By including recursive characterizations of structural properties, the set of conventions can be used to coordinate communication of an unbounded set of meanings with a relatively small set of conventions. Analyses of structural mappings between signals and meanings are used by learners as they attempt to discover the conventions the users of a communication system obey, and as they attempt to perform derivations of signals and meanings in accord with the conventions.

In this account, syntactic structure is a representation of the conventional aspects of the structural derivations performed by senders and receivers. It is not reducible to the domains of meaning or phonology, although regularities or constraints in either domain may influence aspects of syntactic structure. Other syntactic regularities and constraints can emerge as a result of the negotiation process.

Results from a number of recent computational models consistent with this account suggest that agents with fairly general representational and learning abilities can negotiate communication systems capable of accurately conveying very large numbers of meanings. The systems that emerge from the negotiations incorporate structural regularities and constraints that resemble some aspects of the syntax of human languages.

 Conference site: http://www.infres.enst.fr/confs/evolang/