A preliminary classification of dialogue genres

orCorrelating properties of activities

with properties of dialogue systems

Staffan LarssonDept. of linguistics

Göteborg University

Overview• Introduction• Previous classifications of dialogue• Dimensions of classification• Possible additional activity dimensions• Using the classification: decision graphs

and libraries• Summary & future work

Introduction• Goals

– A classification of dialogue genres (types, kinds, …), relevant for development of dialogue systems

– Correlating properties of activities with properties of dialogue systems

– Investigate how this classification can be used in the development of dialogue systems and applications

• Background: GoDiS– An issue-based dialogue system implemented using

TrindiKit (Larsson 2002)– This talk is done with GoDiS in mind, but it the ideas

presented are intended to more general

Dahlbäck (1997)• Modality: spoken/written• Kinds of agents: human/computer• Interaction: dialogue/monologue• Context : spatial, temporal• Number & type of tasks

– Simultaneous?• Dialogue-task distance

– Similarity of dialogue structure – task structure• Kinds of shared knowledge exploited

– Perceptual, linguistic, cultural

Discussion: Dahlbäck• Several dimensions, some relevant but

some not– We currently assume spoken human-

computer dialogue– Dialogue-task distance perhaps too abstract– Context, kinds of shared knowledge used,

and number of tasks relevant, but not yet included in our classification

– Type of task similar to our concept of activity

Allen et. al. (2001)

technique used

example task

task complexity

dialogue phenomena handled

finite-state script

long-distance dialing

least complex

user answers questions

frame-based getting train timetable info

user asks questions, simple clarifications by system

sets of contexts

travel booking agent

shifts between predetermined topics

plan-based models

kitchen design consultant

dynamically generated topic structures, collaborative negotiation subdialogues

agent-based models

disaster relief management

most complex

different modalities (e.g. planned world and actual world)

Discussion:Allen et. al.• Relates properties of system to

properties of activity, BUT• Based on technologies, not properties of

activities– Dialogue phenomena don’t necessarily

come in lumps• Focus on information seeking and

collaborative planning; some types of dialogue not included– Tutorial, Explanatory, Instructional…

Desiderata for a classification of dialogue

• Based on multiple independent properties of (dialogue in) different activities

• Relating properties of activity to properties of system, formulated in the Information State approach

• Covering not only information seeking and collaborative planning dialogue

• Information State (IS)– an abstract data structure (record, DRS, set, stack

etc.)– accessed by dialogue system modules using

conditions and operations• Dialogue Moves

– utterance function (ask, answer, request etc.)• Update rules

– Modify IS based on on observed moves – Select moves to be performed

• IS Approach implemented in TrindiKit

Background: Information State Approach

Dialogue classification & IS approach

• We want to relate our classification to components of the IS approach:– IS type– Dialogue moves– Update rules

• In this talk, rather informally– For GoDiS, we have more formal

descriptions

Some initial dimensions of classification

• Inquiry-oriented vs. Action-oriented dialogue

• Type of result: simple/complex• Type of external process:

active/passive• Distribution of decision rights:

shared/disjoint

Inquiry-oriented vs. action-oriented dialogue

• IOD: raising and addressing issues – E.g. database search

• AOD: introduces (non-communicative) actions to performed (requests)– E.g. programming a Video Recorder

Dialoguegenre

Moves/rules Information State components

Inquiry-Oriented (IOD)

askanswer

Question stack

Action-Oriented (AOD)

requestconfirm

Action stack

Result type• Is the primary result of the dialogue a simple or a

complex information object?– Simple: proposition, action– Complex: plan, proof, explanation

• Complex results require update rules and information state components (e.g. a tree) enabling incremental construction

• Example: offline planning– U: Get me coffee– R: How do I do that?– U: First, go to the kitchen.– R: OK. And then?– U: Go to the coffee machine.– …

Proactivity of external process

• Passive: database, simple device (e.g. Video Recorder)

• (Pro)active: device, e.g. robot, burglar alarm– May need to interrupt current dialogue, perhaps

even interrupt user utterances• This dimension correlates with

– the way the system is connected to the device • Is the device interface a resource (passive) or a module

(active)?– System intitiative and turntaking mechanisms

Distribution of decision rights• Disjoint: each question directed to a specific DP ; this

DP decides on the answer and does not need to negotiate

• Shared: some question(s) should be answered jointly; negotiation may be needed

• Dialogue system requirements for negotiation:– Dialogue move: propose– Information state component: a stack of pairs of

• issue under negotiation, and• alternative solutions/answers to this issue

• N.B.: we here refer to collaborative negotiation (non-conflicting goals)– E.g. SunDial furniture selection task

activity IOD/AOD

result type external process

decision rights

database search IOD simple: price etc.complex: itinerary

passive (database)

disjoint

ticket booking AOD+ IOD

simple: flight passive (database)

disjoint

simple device control

AOD+ IOD

simple: actions passive or active

disjoint

instructional (sys instructs usr)

AOD+IOD

simple: actions passive (manual)

disjoint

offline planning, incl. itinerary planning, complex device control

AOD complex: plan(s) passive (planner)

shared

online planning, e.g. TRIPS

AOD+ IOD

complex: plan active (device+planner)

shared

explanation IOD complex: proof or explanation

passive (inference engine)

shared

tutorial IOD/ AOD

complex? passive (planner)

disjoint

narration IOD complex: narrative passive disjoint

Possible additional activity-related factors

• Distribution of information– Symmetric: DPs have same kind of information– Asymmetric: DPs have different kinds of information– Relation to distribution of decision rights?

• Shared or conflicting goals– Conflicting goals may lead to non-collaborative

negotiation, which would require argumentation acts, including rhetorical acts

• Number of simultaneous tasks (one or several)– But probably very few activities with just one task

• …

Comments• What we really are classifying are activities

– Table shows a classification of activities according to features of a dialogue system needed to particitpate in dialogues in these activities

• How specific should our activities, or activity types, be?– Action oriented dialogue? Device control? VCR control?

Dialogue with Panasonic VCR 4500? • Is ”genre” still a useful term?

– Could perhaps be reserved for very basic properties, such as IOD/AOD

– Or have genres like ”AOD for active devices and collaborative negotiation and asymmetric distrubution of information”

How can this classification be used?

• Make decision graphs …– … which based on properties of the activity,

including dialogue properties, …– … leads to dialogue genres, or to desired

properties of system.• Based on output of decision graph,

– select the variant of the system closest to the requirements

– E.g. GoDiS for AOD with passive devices and disjoint decision rights

Sample decision graph (partial, and assumes disjoint decision rights)

Does the dialogue involverequests for actions?

Is the goal of the dialogueto control a device?

Is the goal of the dialogueto retrieve information from

a database?

Is the device active?

AOD-PassiveIOD

Libraries?• Disadvantages of ”system variants” approach

– Large number of system variants– Same code respresented in several system variants

• Ideally,– system properties should correlate with modular

libraries of moves, rules, and IS components;– These libraries can be combined into a system

suitable for dialogue in the activity.• Libraries e.g. for

– AOD, IOD– Simple results, complex results– Negotiation

Independent ”decision graphs” for libraries: examples

• Does the dialogue involve questions and answers?– Yes -> use ”IOD” library

• Does the dialogue involve requests for actions?– Yes -> use ”AOD” library

• Does the dialogue involve an active external process?– Yes -> use ”ActiveDevice” library– No -> use the ”PassiveDevice” library

• Are there issues with shared decision rights?– Yes -> use ”Negotiation” library

Libraries, cont’d• Libraries would also simplify

implementation:– Enables upgrading a library without having

to change anything else– E.g. plug in a new analysis of grounding– Allows reuse of the same rules etc. in

multiple genres • However, it may be difficult to achieve

the required degree of modularity

Summary• By

– relating properties of (dialogue in) activities to properties of dialogue systems,

• we can – determine which variant of a system (or

which combination of libraries) to use for a system in a given activity

• We provided a first attempt at such a classification, – and discussed how it could be used

Future work• Extend the number of dimensions of

classification– More activity-related factors– Add modality-related factors?

• Explore the idea of libraries– May be difficult to implement

• (Extend capabilities of GoDiS– Currently, IOD and AOD for passive devices,

disjoint decision rights, asymmetric distribution of information, shared goals, multiple simultaneous tasks)

?

More thoughts• Rule libraries come with infostate

extensions/requirements, and with additional moves– Requirements not only on structure,

but also on how it’s to be used, e.g. What does the order of a queue mean?

Interactive Communication Management

• The presence of ICM may be independent of activity– … but not the form of ICM– Have different ICM grammars for different kinds of

activity– Which factors determine genre-specific ICM?

• Written/spoken• Noisiness• Available modalities• How important to be right? AOD->higher requirements on

recognition, more checks? • Negotiation (in ”alternatives” sense) not really

directly correlated with shared decision rights

Modality-related properties• Written• Spoken

– Not noisy– Noisy

• Determines choice of feedback mechanisms

• To some extent activity-related

Allwood’s activity-based pragmatics

• Levels of activity/context– Physical: artifacts etc.– Biological– Psychological: beliefs, desires, intentions, …– Social: incl. rights & obligations, communicative and task-

related• How do these fit with the proposed activity-related

factors?– Distribution of decision rights: social– Proactivity of external process: Physical (Biological?

Psychological?)– Result type: Psychological?– Information state components: Psychological and social

Cutouts…

GoDiS: an issue-based dialogue system

• Built using TrindiKit– Toolkit for implementing and experimenting with

dialogue systems based on the information state approach

• Explores and implements Issue-based Dialogue Management (IBDM)

• Extends theory to more flexible dialogue– Multiple tasks, information sharing between tasks – Interactive Communication Management (ICM),

including feedback, and grounding– Question accommodation– Negotiation of alternatives– Menu based action oriented dialogue

input inter-pret

TIS

DATABASE LEXICON DOMAIN

data-base

control

update select gene-rate output

lexicon domainknowledge

DME

TrindiKit

GoDiS

GoDiS-IOD GoDiS-AOD

TravelAgency

Auto-route

Xeroxmanual

VCRmanager

IBDM

homedevice

manager

ISapproach

genre-specific

activity-specific

General dialogue phenomena- may appear in any activity

• We assume grounding & accommodation probably present in all spoken H-H dialogue– However, grounding works very differently in noisy

environments, and of course in written dialogue• We don’t use these factors to distinguish activities

Feature Moves/rules Infostatecomponents

ICM & grounding

ICM moves Temporary storage, grounding issues

Question accommodation

Accommodation rules

-

Added 030531• AOD/IOD- complicated cases

– Web search:IOD/AOD; what is a non-communicative action?

– Offline planning (should be IOD, unless DP requested to carry out the plan)

• Distinguish different kinds of computer DPs– Robots vs. Stationary devices, etc.

• Additional dimension– Pronoun resolution needed? Or can it

be ignored? How determine this y looking at dialogue?

• Turntaking related to– Grounding (modality)– Passive/active device– …?

• Why not use all libraries (maximal variants)?– Because more work adapting to new

domains