We discuss issues in designing virtual humans for applications that require long-term voluntary use and the problem of maintaining engagement with users over time. Concepts and theories related to engagement from a variety of disciplines are reviewed. We describe a platform for conducting studies into long-term interactions between humans and virtual agents and present the results of two longitudinal, randomized, controlled experiments in which the effect of manipulations of agent behavior on user engagement was assessed.

中文翻译：

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保持与关系代理人的长期干预接触

我们讨论了为需要长期自愿使用的应用程序设计虚拟人的问题，以及随着时间的推移与用户保持互动的问题。回顾了与来自各种学科的参与相关的概念和理论。我们描述了一个平台，用于对人类和虚拟代理之间的长期交互进行研究，并展示了两个纵向、随机、受控实验的结果，其中评估了代理行为对用户参与度的影响。