ATTENTION, INTENTIONS, AND THE STRUCTURE OF DISCOURSE

Transcription

1 ATTENTION, INTENTIONS, AND THE STRUCTURE OF DISCOURSE Seminar Planungsbasierte Kommunikationsmodelle Shipova Evgeniya 14. Dezember 2011 Universität Potsdam

2 Summary 1. What is discourse? 2. Discourse structure 3. Some discourse phenomena 4. Generalization 5. References

3 Discourse Discourse (from Latin discursus, meaning "running to and from") generally refers to "written or spoken communication". - In semantics and discourse analysis: A generalization of the concept of conversation to all modalities and contexts. - In psycholinguistics: A study of speech on the basis of extralinguistic (pragmatic, socio-cultural, psychological, etc) factors. Each discourse: - is task-oriented - typically involves multiple utterances and multiple participants

4 The structure of discourse linguistic structure (the structure of the sequence of utterances) intentional structure (a structure of purposes) attentional state (the state of focus of attention) linguistic structure intentional structure attentional state from Grosz & Sidner (1986)

5 ICP vs. OCP Initiating conversational participant Other conversational participant(s)

6 Linguistic structure Linguistic structure is the structure of the sequence of utterances that comprise a discourse. Utterances Discourse segments Linguistic structure Boundary markers: - cue phrases: eg. in the first place, incidentally, by the way - more subtle cues: eg. intonation, changes in tense and aspect Linguistic boundary markers can be divided according to whether they explicitly indicate changes in the intentional structure or in the attentional state of the discourse.

7 Intentional structure All discourses and discourse participants have purposes, which: - individuate discourses - distinguish coherent and non-coherent discourses - determine when a sequence of utterances comprises more than one discourse Discourse purpose (DP) underlies engaging in the particular discourse. Discourse segment purpose (DSP) specifies how this segment contributes to achieving the overall discourse purpose. - Dominance: if DSP1 helps to satisfy DSP2 then DSP2 dominates DSP1 - Satisfaction-precedence: if DSP2 must be satisfied before DSP1 then DSP2 satisfaction-precedes DSP1

8 Types of intentions All of them could serve as DPs or DSPs:

9 Attentional state Attentional state is an abstraction of the participants focus of attention as their discourse unfolds. It is modeled by a set of focus spaces, that together form focusing structure. Focusing structure: - is parasitic upon the intentional structure - evolves as the discourse proceeds A focus space is associated with each DS and contains it s salient entities. Attentional state is represented as a stack data structure.

10 Stack structure

11 Intentional structure vs. Attentional state Intentional component provides a complete record is full at the end can t constrain the interpretation of referring expressions Attentional component contains relevant information is empty at the end constrains the interpretation of referring expressions

12 Example (a rhetoric text from Holmes and Gallagher 1917)

13 Example

14 Example

15 Processing issues: Processing issues include specifying: how the ICP indicates and the OCP recognizes the beginning and the end of a discourse segment; how the OCP recognizes the discourse segment purposes; how the focus space stack operates. This is important for using the theory in constructing computational models.

16 Intention recognition The recognition of DP/DSPs is the central issue in the computational modeling of intentional structure. OCP recognize intentions using a variety of sources: - specific linguistic markers; - utterance-level intentions; - general knowledge about the world; - intonational properties.

17 Use of the attentional state model The attentional state model is used: - To constrain the range of DSPs considered as candidates for domination or satisfaction-precedence of the DSP of the current segment; - To constrain the OCP s search for possible referents of definite noun phrases and pronouns.

18 Cue words Cue phrases provide indirect means of indicating changes of the attentional state and the intentional structure. They also allow the OCP to determine these changes. In discourse changes OCP must determine: 1) that a change of attention is imminent; 2) whether the change returns to a previous focus space or creates a new one; 3) how the intention is related to other intentions; 4) what precedence relationships, if any, are relevant; 5) what intention is entering into focus. (1)-(4) can be identified by cue words.

19 Cue words - examples Case 1: a change to some new purpose + the new purpose is dominated by the previous one eg. for example, to wit, first, second Case 2: a satisfaction-precedence relationship eg. - B is the first in a list of DSPs dominated by A: first, in the first place - Further DSPs that are dominated by A and satisfaction-preceded by B: second, third, finally

20 Interruptions Interruptions are pieces of discourse that break the flow of the preceding discourse. After the break for the interruptions, the discourse returns to the interrupted piece. eg.

21 Types of interruptions True interruption is a discourse segment whose DSP is not dominated nor satisfaction-preceded by the DSP of any preceding segment (strong definition). eg. Excuse me, wait a second Flashback is a segment whose DSP satisfaction-precedes the interrupted segment and is dominated by some other segment s DSP. eg. Oops, I forgot about Digression is a strong interruption that contains a reference to some entity that is salient in both the interruption and the interrupted segment. eg. Speaking of John Semantic returns introduce a focus space used in a previous discourse. eg. Remember our discussion about Jack at the party?..

22 Generalization Discourse: linguistic/intentional/attentional components Explaining: interruptions/cue phrases/referring expressions Investigating the structure and meaning of discourse and construction discourse-processing systems

23 References Grosz & Sidner (1986). Attention, intentions, and the structure of discourse.

24 Thank you!