  When individuals engage in spoken discourse, various phenomena can be
observed that differ from those that are apparent in text-based conversation.
While written communication commonly uses a question mark to denote a query, in
spoken discourse, queries are frequently indicated by a rising intonation at
the end of a sentence. However, numerous speech recognition engines do not
append a question mark to recognized queries, presenting a challenge when
creating a spoken dialogue system. Specifically, the absence of a question mark
at the end of a sentence can impede the generation of appropriate responses to
queries in spoken dialogue systems. Hence, we investigate the impact of
question marks on dialogue systems, with the results showing that they have a
significant impact. Moreover, we analyze specific examples in an effort to
determine which types of utterances have the impact on dialogue systems.

Computation and Language