Lexical Accommodation in Machine-Mediated Interactions

LEXICAL ACCOMMODATION IN MACHINE-MEDIATED INTERACTIONS Laurel Fais ATR Interpreting Telecommunications Research Laboratories 2-2 Hikaridai, Seika-cho Soraku-gun Kyoto, Japan 619-02 email: fais@itl.atr.co.jp Abstract We report results of lexical accommodation studies involving three different interpretation settings: human-human monolingual; human-interpreted bilingual; and machine-interpreted bilingual. We found significant accommodation in all three conversational settings, with the highest rate in the human-interpreted setting. There is evidence for long- range mutual accommodation in that setting, as compared to short-range accommodation in the machine-interpreted setting. Motivations discussed in the accommodation literature, including speakers' concern for social standing and communicational efficiency, are examined in the light of the results obtained. Finally, we draw implications for the design of multimedia human-computer interfaces. 1 Introduction For real-time, real-situation, human-computer interaction to approach reality, the burden of understanding and conveying information cannot be shared equally between the two interaetors. Humans need to make allowances for features of the computer interface such as synthesized speech, limitations on range of knowledge base, and imperfect speech recognition. However, in order for naive users to accept and use computers effectively in an interactive format, the restrictions placed upon them need to be as minimal and as natural as possible. Exploring the linguistic behavior of humans interacting with computers in an unrestricted environment allows us to determine how humans are naturally inclined to accommodate to the current limitations of human- machine interaction. Encouraging those natural inclinations in real human-machine systems will have a better chance of success than imposing artificial restrictions. In addition, systems designers can take advantage of the accommodations that humans make naturally to improve the performance of their systems (Fais et al., 1995) Below, we will discuss a particular kind of accommodation in conversational interaction, namely lexical accommodation. In lexical accommodation, one conversant adopts the lexical items used by the other conversant. This type of accommodation is one way in which users adapt to the limitations of computer interfaces, i.e., they converge to the limited lexicon of the computer. Thus, it has important implications for the design of workable human- computer interfaces. We discuss experiment results from three conversational settings: human-human monolingual; human-interpreted bilingual, and machine-interpreted bilingual. 1.1 Background Of course, there is no a priori reason why interactors could not conduct conversations in completely different styles, using different phonologies, sentence structures, vocabulary, etc. However, it has been widely demonstrated that they do not. Lexical accommodation is only one instance of a diverse range of convergence behaviors that humans display in conversation. Giles etal. (1987) cite studies demonstrating convergence of speech styles, dialect, non-verbal behavior, vocal intensity, prosody, speech rate and duration, and pause length. Garrod and Doherty (1994) report on a study in which conversational interactors in a language community showed a high level of convergence on a particular description language over the course of the task (a maze game). Fais (1994a) discusses both lexical and syntactic accommodation over a range of natural conversational styles. Accommodation has also been shown to be present in human-computer interactions. Zoltan-Ford (1991) and Leiser (1989) demonstrate …

Content truncated to 500 words