Event Calculus with Explicit Quantifiers

Kowalski and Sergot's (1986) Event Calculus (EC) is a simple temporal formalism that, given a set of event occurrences, derives the maximal validity intervals (MVIs) over which properties initiated or terminated by these events hold. We extend this calculus to give a semantic foundation to our Quantifiers and Connectives Event Calculus (QCEC). In particular, we extend the range of queries accepted by EC, which has so far been limited to Boolean combinations of MVI verification or computation requests, to admit arbitrary quantification over events and properties. We demonstrate the added expressive power by encoding a medical diagnosis problem as a case study. Moreover, we give a /spl lambda/Prolog implementation of this formalism and analyze the computational complexity of the extended calculus.

Authors

• Iliano Cervesato
• Massimo Franceschet
• Angelo Montanari

Keywords

• Calculus
• Medical diagnosis
• Logic programming
• Computer science
• Encoding
• Computational complexity
• Boolean functions
• Research initiatives
• Casting
• Polynomials
• Event Calculus
• Diagnostic Methods
• Range Query
• Semantic
• Boolean Operators
• Disjunction
• Partial Order
• Binary Relation
• Model Checking
• Program Logic
• Strict Order
• Transitive Closure
• Logical Language