Technologies pertaining to human-robot interaction are described herein. The robot includes a computer-readable memory that comprises a model that, with respect to successful completions of a task, is fit to observed data, where at least some of such observed data pertains to a condition that is controllable by the robot, such as position of the robot or distance between the robot and a human. A task that is desirably performed by the robot is to cause the human to engage with the robot. The model is updated while the robot is online, such that behavior of the robot adapts over time to increase the likelihood that the robot will successfully complete the task.