Speaker-centred syntax in dialogue: Evidence against cooperation

McLean, J. F., Branigan, H. P. and Reeve, H. M.
University of Edinburgh

Previous research has suggested a preference for Given-New ordering in language (e.g., Clark & Clark, 1978). However, it is not clear how to account for this preference in cognitive models of human communication. Theories of dialogue often assume that speakers are maximally cooperative: Utterances are designed to be easily understood by the addressee (e.g., Clark & Wilkes-Gibbs, 1986), and Given-New ordering reflects comprehenders' preference for that ordering (Clark & Haviland, 1977). Conversely, theories of language production stress the importance of speakers' ease of processing (e.g., Levelt, 1989); speakers prefer Given-New ordering because it promotes incremental production (e.g., Bock & Irwin, 1980). We report two picture description experiments that investigated whether Given-New ordering is listener- or speaker-centred behaviour. A "speaker" described pictures to a "listener", who decided whether their pictures matched each description. In critical trials, the speaker's picture showed a transitive action involving an inanimate agent and an animate patient (e.g., a sword stabbing a pilot). The Givenness of the relevant entities was varied independently for the speaker and the listener. In the Baseline condition, both entities were New to the speaker and listener. In the Both-Given condition, both participants were shown a preliminary picture that introduced one of the two entities (e.g., either the sword or the pilot), thus rendering one entity speaker- and listener-Given. In the Speaker-Given condition, only speakers were shown the preliminary picture (hence both entities were listener-New). If speakers produce Given-New ordering to facilitate listeners' comprehension, they should only do so in situations where listeners have the same knowledge. If however speakers produce Given-New ordering to ease their own processing burden, they should do so irrespective of whether the listener has the same knowledge. In Experiment 1, we found that entities that were Given to the speaker were produced in early word order positions. However, this effect did not interact with listener knowledge: Speakers produced entities that were speaker-Given in early word order positions irrespective of whether the entity was also listener-Given. Experiment 2 used the same manipulation, but allowed listeners to interact more freely with the speaker, to see whether the absence of a Listener knowledge effect in Experiment 1 was attributable
to restricted interactivity (Krauss & Weinheimer, 1966). The same pattern of results was found. Our results suggest that speakers are not necessarily syntactically cooperative in dialogue, in keeping with previous findings for reference (Horton & Keysar, 1996). They support models of communication that stress the importance of the speaker's ease of processing in determining syntactic structure.

References

Bock, J. K., & Irwin, D. E. (1980). Syntactic effects of information availability in sentence production. Journal of Verbal Learning and Verbal Behavior, 19(4), 467-484.

Clark, E. & Clark, H. (1978). Universals, relativity, and language processing. In J. Greenberg (Ed.), Universals of Human Language, Volume 1: Method and Theory (pp. 225-277). Stanford: Stanford University Press.

Clark, H.H., & Haviland, S.E. (1977). Comprehension and the Given-New contract. In R. Freedle (Ed.), Discourse production and comprehension. New York: Ablex.

Clark, H.H., & Wilkes-Gibbs, D. (1986). Referring as a collaborative process. Cognition, 22, 1-39.

Horton, W., & Keysar, B. (1996). When do speakers take into account common ground? Cognition, 59, 91-117.

Krauss, R. M., & Weinheimer, S. (1966). Concurrent feedback, confirmation and the encoding of referents in verbal communication. Journal of Personality and Social Psychology, 4, 343-346.

Levelt, W. J. M. (1989). Speaking: From Intention to Articulation. Cambridge, MA:MIT Press.