@TechReport{	  it:2012-006,
  author	= {Johanna Bj{\"o}rklund and Eric J{\"o}nsson and Lisa Kaati},
  title		= {Aspects of Plan Operators in a Tree Automata Framework},
  institution	= {Department of Information Technology, Uppsala University},
  year		= {2012},
  number	= {2012-006},
  month		= apr,
  abstract	= {Plan recognition addresses the problem of inferring an
		  agents goals from its action. Applications range from
		  anticipating care-takers' needs to predicting volatile
		  situations. In this contribution, we describe a prototype
		  plan recognition system that is based on the
		  well-researched theory of (weighted) finite tree automata.
		  To illustrate the system?s capabilities, we use data
		  gathered from matches in the real-time strategy game
		  StarCraft II. Finally, we discuss how more advanced plan
		  operators can be accommodated for in this framework while
		  retaining computational efficiency by taking after the
		  field of formal model checking and over-approximating the
		  target language.}
}