Nature – Laboratory
Discourse completion tests ask participants to provide the missing turns in invented conversations. Whether they are oral or written, DCTs present the informants with specific situations in which they have to react, either by paying a compliment or by responding to one. It depends on the ingenuity of the researcher to come up with conversations that elicit exactly the kind of speech act that he or she wants to investigate. Thus the researcher needs to know the kind of situation in which this particular speech act is likely to occur. It must be clear to the researcher even before the investigation what the nature of the speech act should be. Thus the research cannot be expected to reveal new insights into the nature of the speech act.
In fact, participants may even be too cooperative. In the experimental setting, they may be prepared to carry out tasks and to perform speech acts that are very unlikely to occur in their real lives. Compliments in Japanese, for instance, are considered to pose a considerable face-threat to the addressee since the addressee in responding is forced to violate either the maxim of modesty or the maxim of agreement. Therefore speakers of Japanese don’t pay compliments as easily as speakers of American English. However, faced with a discourse completion test, they are likely to try to be cooperative and pay a compliment that they would be very unlikely to do in real life.