Speakers Reduce Because of Their Own Internal Representations

1. Speakers Reduce Because of Their Own Internal Representations Jason Kahn Jennifer Arnold UNC – Chapel Hill

2. You really have to watch Federer to understand the beauty of top-flight sports performance. Sure, but do you think tennis is as accessible to middle America as football?

3. You really have to watch tennis to understand the beauty of top-flight sports performance. Sure, but do you think tennis is as accessible to middle America as football?

4. Repeated Mentions Get Reduced (e.g. Bard et al., 2000; Fowler & Housum, 1987) Linguistically New Discourse Status Linguistically Given Discourse Status You really have to watch Federer to understand the beauty of top-flight sports performance. You really have to watch tennis to understand the beauty of top-flight sports performance. …tennis… …tennis… -givenness -predictability +givenness +predictability

5. General Questions • What mechanism drives reduction? • Does it involve audience design?

6. Audience Design • Broadly speaking, designing utterance with audience in mind • When it comes to acoustic reduction… • Joint Discourse Status – represented explicitly, defined as shared information • Facilitated processing • For the speaker • For the listener

7. Why shorter duration on second mention?Joint discourse status “Tennis” Givón, 1983; Grosz et al., 1995

8. Why shorter duration on second mention?Speaker-internal Activation(The alternative - our proposal) “Tennis”

9. Research Questions • Must we explicitly represent discourse status for the purposes of reduction? • Or can we account for the same data by focusing on the activation of other necessary representations? • Must we explicitly represent the listener’s knowledge? • Or is audience design not the primary motivator?

10. Joint Discourse Status CONCEPTUALIZATION STAGE DISCOURSE STATUS (given vs. new) (what speaker and listener both know) FORMULATION STAGE ARTICULATION STAGE Adapted from Levelt (1989), Schmitt, Meyer & Levelt (1999), and van der Meulen, Meyer, & Levelt (2001)

11. Joint Discourse Status CONCEPTUALIZATION STAGE DISCOURSE STATUS (given vs. new) (what speaker and listener both know) “tennis” +givenness +predictability Topic continuity tracks givenness information - in other words, givenness also creates predictability information Fowler & Housum, 1987; Prince 1992

12. Activation-based CONCEPTUALIZATION STAGE FORMULATION STAGE ARTICULATION STAGE Adapted from Levelt, 1989; c.f. Balota, Boland & Shields, 1989; Bard et al., 2000; Bell et al., 2009

13. Activation-based givenness CONCEPTUALIZATION STAGE “tennis” predictability FORMULATION STAGE Both predictability and givenness should create activation, and thus should be separable

14. Linguistic vs. Non-linguistic Givenness “The accordion…”

15. Linguistic vs. Non-linguistic Givenness “The accordion…” Joint Discourse Speaker-internal CONCEPTUALIZATION STAGE DISCOURSE STATUS (given vs. new) (what speaker and listener both know) CONCEPTUALIZATION STAGE FORMULATION STAGE FORMULATION STAGE Bard & Anderson, 1990; Clark & Marshall, 1981; Prince, 1992

16. Instruction-giving Task Listener Approximately 12 feet Speaker

17. Experimental Paradigm Speaker: “The accordion rotates right” Speaker: “The toothbrush shrinks” Speaker: “The belt expands”

18. Experiment 1: Priming Information Control Non-linguistic Linguistic “The toothbrush; The belt; The accordion”

19. Joint Discourse Status predicts…. Activation-based predicts…

20. Reduced Duration of the Object Word Linguistic < Non-linguistic < Control * *

21. Activation-based Naturally Accounts For These Findings Non-linguistic information led to reduction Linguistic information led to more reduction This task used predictability as a control to investigate givenness…

22. Predictability & Givenness • A discourse status account predicts that givenness and topic continuity (i.e. predictability) pattern together, in the same representation • By contrast, an activation-based model allows either predictability or givenness to lead to reduction. Fowler & Housum, 1987; Prince 1981

23. Experiment 2: Target Given1/8 of trials Non-linguistic Linguistic “The accordion”

24. Experiment 2: Target New7/8 of trials Non-linguistic Linguistic “The toothbrush”

25. Reduced Duration of the Object Word Target Given < Target New *

26. Further Confirmation • Even in the absence of strong predictability, speakers reduce in response to linguistic givenness information • Exp.’s 1 & 2 suggest that speakers do not need to model discourse status explicitly for reduction

27. Speaker-internal Audience Design? • Traditional views of discourse status say that speakers use it in part to model the listener (Clark & Marshall, 1981; Gundel et al., 1993) • But if we do away with a representation of discourse status here, we should still ask whether speakers do it because of themselves or because of their listeners

28. Instruction-giving Task v v v v Blocked trials Icon at the top of the screen Headphones Listener Speaker

29. Reduced Object Duration (Both, Speaker) < (Listener, None)

30. Speaker-internal Activation • If speakers were tracking discourse status, they should have shown a different pattern of reduction • Even without discourse status, speakers could have reduced for their listener, but did not

31. Summary of Results • Linguistic givenness elicited more reduction than non-linguistic givenness in Experiment 1 • Linguistic givenness elicited reduction even without strong predictability in Experiment 2 • Speakers reduced when, and only when, they had givenness information in Experiment 3 (the listener doesn’t matter here)

32. Non-linguistic givenness created reduction CONCEPTUALIZATION Linguistic givenness created more reduction FORMULATION Givenness and predictability have separable effects, suggesting a common substrate, namely activation.

33. Discourse Status Matters Elsewhere • Word order (Arnold, Wasow, et al., 2000; Birner & Ward, 1994) • Lexical choice (e.g. pronouns vs. more explicit expressions) (Ariel, 2000; Arnold, 1998; Gundel et al., 1993) • Accenting (Pierrehumbert & Hirschberg, 1990)

34. Other Potential Models • These results are still technically consistent with a model that includes an explicit representation of discourse status at the conceptual level. • But we propose that our model is both more parsimonious and makes additional predictions, which we are currently testing

35. The Role of Audience Design • Has effects on word choice, amount of detail, number of words (Arnold, Kahn & Pancani (CUNY Poster Thursday); Bard et al., 2000; Galati & Brennan 2010) • The effect of audience design on reduction is mediated by the speaker’s internal representations (c.f. Balota, Boland & Shields, 1989; Bard et al., 2000)

36. The Role of Audience Design Arnold, Kahn & Pancani, CUNY Poster Thursday

37. Take Home Message Slide • Speakers reduce based on the state of their own internal representations • They don’t appear to need an explicit representation of discourse status • They don’t appear to track the state of their listener(s)

38. With Gratitude To… • The Cognitive and Language groups at UNC for endless discussion, support, and critique • Kellen Carpenter, Giulia Pancani, Alex Christodoulou, Alyssa Ventimiglia, Jennifer Tate, Sam Handel, and Leighanne McGill for help with these experiments • And Ellen Bard, Scott Fraundorf, Florian Jaeger, Tuan Lam, Janet Pierrehumbert, and Joseph Tyler for useful discussions