Formally modeling pretend object play

We address the problem of building computational agents that are capable of play. Existing research has examined the forms, characteristics, and processes involved in various kinds of play at a high level. However, this research does not provide a unified framework at a level of detail sufficient for building computational agents that can play. As a step toward addressing this gap we synthesize diverse research on pretend play to recognize important components of pretend play agents. We also develop a formal model of one key component of pretend play, pretend object play, and present a computational implementation of this model. Our work provides initial criteria for the content and processes necessary for pretend play agents.