Twin-Robot Dialogue System with Robustness against Speech Recognition Failure in Human-Robot Dialogue with Elderly People

As agents, social robots are expected to increase opportunities for dialogue with the elderly. However, it is difficult to sustain a dialogue with an elderly user because speech recognition frequently fails during the dialogue. Here, to overcome this problem, regardless of speech recognition failure, we developed a question–answer–response dialogue model. In this model, a robot took initiative in the dialogue by asking the user various questions. Moreover, to improve user experience during dialogue, we extended the model such that two robots could participate in the dialogue. Implementing these features, we conducted a field trial in a nursing home to evaluate the twin-robot dialogue system. The average word error rate of speech recognition was 0.778. Despite the frequently high number of errors, participants talked for 14 min in a dialogue with two robots and felt slightly strange during the dialogue. Although we found no significant difference between a dialogue with one robot and that with two robots, the effect size of the difference in the dialogue time with one robot and that with two robots was medium (Cohen’s d = −0.519). The results suggested that the presence of two robots might likely encourage elderly people to sustain the talk. Our results will contribute to the design of social robots to engage in dialogues with the elderly.

A Case Study on Intermediate CSL Learners’ Word Recognition Processes and Strategies in Contextual Reading Settings

This study investigates word recognition processes and strategies of intermediate learners of Chinese as a Second Language (CSL) in contextual reading settings. Two intermediate CSL learners were chosen as research participants, and think-aloud methods and retrospective interviews were used to collect data. The data were analyzed by using Moustakas’ data analysis procedure, Creswell’s three steps and Bogdon and Biklen’s data analysis methods. Results indicated that intermediate CSL learners go through different processes of word recognition as it might be automatic, based on context, pronunciation, previous knowledge and the meaning of characters, or, in case of word recognition failure, skipping the words or skipping them but reading them again later; and their word recognition strategies in contextual reading settings mainly include cognitive strategies and self-regulatory strategies. Among these strategies, cognitive strategies consist of direct transformation, translation, interpretation, guessing, inferring and finding key words; and self-regulatory strategies include metacognitive strategies, behavior regulating strategies, emotion regulating strategies and motivation regulating strategies. A model of intermediate CSL learners’ word recognition strategies can be constructed based on the results. The present study provides both theoretical and pedagogical implications in the field of CSL vocabulary acquisition and teaching.