Airborne tactical decision making is degraded as a result of sophisticated threat capabilities, high data rates and uncertainties, and the necessity for timely response. Under investigation at the Naval Air Development Center is the concept of a plan recognition model to assist the tactical decision maker in interpreting and predicting the activities of enemy platforms.* On-going work in the fi...

We present a novel approach to plan recognition based on a two-stage paradigm of graph construction and analysis. First, a graph structure called a Goal Graph is constructed to represent the observed actions, the state of the world, and the achieved goals as well various connections between these nodes at consecutive time steps. Then, the Goal Graph is analysed at each time step to recognise th...

Referring expressions such as “a long meeting” and “a restaurant near my brother’s” depend on information from the context to be accurately resolved. Interpreting these expressions requires pragmatic inferences that go beyond what the speaker said to what she meant; and to do this one must consider the speaker’s decisions with respect to her initial belief state and the alternative linguistic o...

Proficient teams can accomplish goals that would not otherwise be achievable by groups of uncoordinated individuals. This thesis addresses the problem of analyzing team activities from external observations and prior knowledge of the team’s behavior patterns. There are three general classes of recognition cues that are potentially valuable for team activity/plan recognition: (1) spatial relatio...

Plan recognition has to be performed in a statistically robust manner concerning a possibly infinite number of tactical situations and different types of units. We need a generic model for tactical plan recognition where we combine observations and a priori knowledge in a flexible manner by using suitable methodologies and by having a large hypothesis space taken into account. Threat and theref...

We propose a new probabilistic plan recognition algorithm YR based on an extension of Tomita’s Generalized LR (GLR) parser for grammars enriched with the shuffle operator. YR significantly outperforms previous approaches based on topdown parsers, shows more consistent run times among similar libraries, and degrades more gracefully as plan library complexity increases. YR also lifts the restrict...

It is important for agents to model other agents’ unobserved plans and goals, based on their observable actions, a process known as plan recognition. Plan recognition often takes the form of matching observations of an agent’s actions to a planlibrary, a model of possible plans selected by the agent. In this paper, we present efficient algorithms that handle a number of key capabilities implied...

This paper presents a new algorithm for plan recognition called ELEXIR (Engine for LEXicalized Intent Recognition). ELEXIR represents the plans to be recognized with a grammatical formalism called Combinatory Categorial Grammar(CCG).We show that representing plans with CCGs can allow us to prevent early commitment to plan goals and thereby reduce runtime.

Data warehouse related technologies, allows to extract, group and analyze historical data in order to identify information valuable to decision making processes. In this paper the implementation of a weather data warehouse (WDW) to store Mexico’s weather variables is presented. The weather variables data were provided by the Mexican Institute for Water Technologies (IMTA), the IMTA does researc...