Help or Hinder: Bayesian Models of Social Goal Inference.

Everyday social interactions are heavily influenced by our snap judgments about others' goals. Even young infants can infer the goals of intentional agents from observing how they interact with objects and other agents in their environment: e.g., that one agent is 'helping' or 'hindering' another's attempt to get up a hill or open a box. We propose a model for how people can infer these social goals from actions, based on inverse planning in multiagent Markov decision problems (MDPs). The model infers the goal most likely to be driving an agent's behav- ior by assuming the agent acts approximately rationally given environmental con- straints and its model of other agents present. We also present behavioral evidence in support of this model over a simpler, perceptual cue-based alternative.