Yet Another Probabilistic Plan Recognizer (YAPPR)

YAPPR is a plan recognition system, written in Lisp, designed by SIFTers and Dr. Christopher W. Geib of the University of Edinbugh. This team has deployed Yappr as part of both the Poirot system from the Integrated Learning program, and the SDPR network security system for the SRS program. Yappr represents a breakthrough in the complexity of probabilistic plan recognizers, allowing this technology to be applied to much broader applications. Technical details about Yappr are available in a paper presented at ICAPS 2008.