In this paper we present a Multimodal Echoborg interface to explore the effect of different embodiments of an Embodied Conversational Agent (ECA) in an interaction. We compared an interaction where the ECA was embodied as a virtual human (VH) with one where it was embodied as an Echoborg, i.e, a person whose actions are covertly controlled by a dialogue system. The Echoborg in our study not only shadowed the speech output of the dialogue system but also its non-verbal actions. The interactions were structured as a debate between three participants on an ethical dilemma. First, we collected a corpus of debate sessions with three humans debaters. This we used as baseline to design and implement our ECAs. For the experiment, we designed two debate conditions. In one the participant interacted with two ECAs both embodied by virtual humans). In the other the participant interacted with one ECA embodied by a VH and the other by an Echoborg. Our results show that a human embodiment of the ECA overall scores better on perceived social attributes of the ECA. In many other respects the Echoborg scores as poorly as the VH except copresence.

在本文中，我们提出了一个多模式 Echoborg 界面，以探索交互中具体会话代理 (ECA) 的不同实施例的效果。我们将 ECA 体现为虚拟人 (VH) 的交互与体现为 Echoborg（即其行为受到对话系统秘密控制的人）的交互进行了比较。我们研究中的 Echoborg 不仅影响了对话系统的语音输出，还影响了其非语言行为。互动的结构是三个参与者之间关于道德困境的辩论。首先，我们收集了三名人类辩手的辩论会议语料库。我们以此为基准来设计和实施我们的 ECA。对于实验，我们设计了两种辩论条件。在其中一项中，参与者与两个 ECA 进行交互，这两个 ECA 均由虚拟人体现）。在另一项中，参与者与一个由 VH 体现的 ECA 和另一个由 Echoborg 体现的 ECA 进行交互。我们的结果表明，ECA 的人类体现在 ECA 的感知社会属性方面总体得分更高。在许多其他方面，除了共存性之外，Echoborg 的得分与 VH 一样差。