Accounting for redundant referring expressions: continuous semantics and/versus incrementality
Reference is one of the most basic and prevalent functions of language use. A long-standing puzzle in language production is that speakers routinely include redundant modifiers in their referring expressions, i.e., modifiers that aren't strictly speaking necessary for the purpose of uniquely establishing reference. This redundancy has been argued to violate the tenets of rational language use, thus posing a challenge for standard pragmatic and psycholinguistic theories that treat language production as an efficient tradeoff between maximizing utterance informativeness and minimizing utterance cost.
I show that maintaining the standard theory (as formalized within the Rational Speech Act framework), but relaxing the semantics of words, yields a number of well-documented patterns whereby redundancy is modulated by linguistic and extra-linguistic contextual factors. These include adjective type (more redundant color than size or material adjective use), scene variation (more redundant modification in more complex visual displays), and property typicality (more redundant modification in reference to objects with more atypical properties). However, this model does not capture a key result: that redundancy appears to be less likely in languages with post-nominal modifiers, like Spanish. I describe the cross-linguistic predictions of an incrementalized version of the model and present preliminary data from an emerging village sign language (CTSL) with no established referential strategies. The data call into question the relative importance of language structure and incrementality over perception in redundant modification and highlights two needs: i) for more explicit formalizations of notions of efficiency in language production; and ii) for further cross-linguistic investigations of reference.