Dialogue Act Coding and ModalitiesGSLT: Dialogue Systems

Leif Grönqvist – leifg@ling.gu.se

11. June 2002 15:30

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Presentation Outline

• Properties for dialogue act (in particular) coding schemes

• Mode – medium – modality

• Modality Theory

• The different coding schemes

• Some interesting differences between the coding schemes

• Conclusions

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Properties for dialogue act coding schemes

• How general is it?• Is it powerful enough for natural

dialogue?• Does the scheme handle different

modalities?• Are the definitions precise enough to

make the scheme useful in dialogue systems?

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More properties for coding schemes

• Multi functional codings

• Mutual exclusive categories

• Discontinuous codings

• Relational codings

• Hierarchical coding values

• Multi-layer scheme

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Mode – medium – modality

• Some terms are used in different ways in different contexts

• Bretan and Bernsen use “modality” in the same way but psychologists do not.

• B & B do not agree on the term “medium”• Bernsen: “We should aim for a

terminology that is robust, conceptually clear and intuitively accepted.”

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Modality Theory

• Niels Ole Bernsen’s theory: “A generative taxonomy of output modalities”

• Start with a set of basic features: Linguistic/non-linguistic(non-)analogue(non-)arbitrarystatic/dynamicgraphics/sound/touch

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Modality Theory 2

• Combine them to get 48 distinct types

• Remove impossible combinations: 20 left

• One more feature:

Real world/diagrammic/graphs

resulting in 28 distinct modalities

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• 28 unimodal modalities

• Use of more than one will result in multimodality

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Selected Coding Schemes for Dialogue Acts

• LINLIN 1/2: Linköping, Ahrenberg et al, 1995• HCRC: Developed for the Map Task Corpus,

Andersson et al 1991• DAMSL: By Discourse Resource Initiative as

a standardized coding scheme, 1991• SWBD-DAMSL: Modified DAMSL by Stolcke

et al 2000• GBG: Communicative Acts by Allwood 2000

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Why these

• They cover some different types

• And are developed for different purposes

• Some of them are widely spread and well known

• I know something about them

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Interesting differences

• LINLIN and DAMSL are more general than GBG and HCRC

• GBG and DAMSL are the more powerful• DAMSL and HCRC do not handle non-

verbal dialogue acts as well as LINLIN and GBG

• GBG is the only one not directly useful in dialogue systems

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Conclusions

• Some researchers does not seem to believe in non-verbal dialogue acts at all:

in SWBD-DAMSL the coding types are mutually exclusive and two of the most common are:

Backchannel/Acknowledge

Non-verbal

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More conclusions• The linguists scheme (GBG) is very rich

but not useful I a dialogue system context• Modality should not be used to define

dialogue act categories – but in a second layer.

• Our intuition says that a nod or pointing at something could be an answer to a question

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We are done

And probably out of time