Development and portability of ASR and Q&A modules for real-environment speech-oriented guidance systems

In this paper, we investigate development and portability of ASR and Q&A modules of speech-oriented guidance systems for two different real environments. An initial prototype system has been constructed for a local community center using two years of human-labeled data collected by the system. Collection of real user data is required because ASR task and Q&A domain of a guidance system are defined by the target environment and potential users. However, since human preparation of data is always costly, most often only a relatively small amount real data will be available for system adaptation in practice. Therefore, the portability of the initial prototype system is investigated for a different environment, a local subway station. The purpose is to identify reusable system parts. The ASR module is found to be highly portable across the two environments. However, the portability of the Q&A module was only medium. From an objective analysis it became clear that this is mainly due to the environment-dependent domain differences between the two systems. This implicates that it will always be important to take the behavior of actual users under real conditions into account to build a system with high user satisfaction.