Limited Vocabulary Natural Language Dialogue*

Subjects cooperatively solved credible, realworld problems while communicating through a computer controlled teletype system and using three different sizes of available vocabulary in a simulation of a limited vocabulary natural language computer system. Although subjects sometimes exhibited frustration with the small vocabularies, analyses of 21 dependent measures indicated that they were able to interact and solve the problems about as successfully as did their counterparts who completed the same problems with no vocabulary restrictions. The results indicate that, at least for the kinds of problems tested here, it should be possible to develop a vocabulary of limited size which is still efficient to use in the type of interactive communication that might characterize natural language computer systems of the future.