Using informative behavior to increase engagement in the TAMER framework

In this paper, we address a relatively unexplored aspect of designing agents that learn from human training by investigating how the agent's non-task behavior can elicit human feedback of higher quality and quantity. We use the TAMER framework, which facilitates the training of agents by human-generated reward signals, i.e., judgements of the quality of the agent's actions, as the foundation for our investigation. Then, we propose two new training interfaces to increase active involvement in the training process and thereby improve the agent's task performance. One provides information on the agent's uncertainty, the other on its performance. Our results from a 51-subject user study show that these interfaces can induce the trainers to train longer and give more feedback. The agent's performance, however, increases only in response to the addition of performance-oriented information, not by sharing uncertainty levels. Subsequent analysis of our results suggests that the organizational maxim about human behavior, "you get what you measure" - i.e., sharing metrics with people causes them to focus on maximizing or minimizing those metrics while de-emphasizing other objectives - also applies to the training of agents, providing a powerful guiding principle for human-agent interface design in general.