Dialogue Acts Recognition - Man-Machine Dialogue: Design and Challenges - page 118

- a chain of the previously expressed acts, like in a language model, and to
use methods such as CRF and HMM (see section 2.1.3).
Jurafsky and Martin [JUR 09, p. 880] emphasize that the module devoted
to act recognition can be divided into two parts: in charge of general acts and
in charge of recognizing specific acts such as corrective acts on the user's part
following a system's error. Both parts operate in the same way, that is in the
current systems they operate according to a labeling task after a machine
learning phase, but with different models. The corrective utterances are
indeed harder to recognize than the regular utterances and require specific
indications such as the presence of words like “no” or “I do not have”, the
presence of a repetition, potentially with an exaggerated articulation, a
paraphrase, an addition or omission of content.
7.2.2. Indirect and composite acts
The identification process of indirect acts takes up the same parameters as
those presented in the previous section, but it also emphasizes four additional
aspects which are particularly important:
- An index of dialogue conventions, which includes a few typical examples
of indirect acts: if the situation being processed matches one of the examples,
then the system can rely on the suggested solution.
- The speaker's preferences, that is the user model, if it has been updated
as the dialogue progresses, especially in cases of indirect act detection (“when
he/she says this it is to do that”).
- The system's task model, and especially the list of its abilities: this is
indeed a means to identify indirect acts such as “can you hear me?”.
- The hypotheses on the user's mental states, following, for example, a BDI
model (see section 2.1.2), so that the system can detect when the user already
knows the answer to the query it is making, to interpret it as an indirect act.
In the same way, composite act identification requires a similar list of
parameters with a few changes:
- A set of words and linguistic constructions which are often used
to express an act of second intent: epithet adjective, evaluating adverbs,
appositions, relative clauses, etc.