We present a system for deciding whether a given sentence can be inferred from text. Each sentence is represented as a directed graph (extracted from a dependency parser) in which the nodes represent words or phrases, and the links represent syntactic and semantic relationships. We develop a learned graph matching model to approximate entailment by the amount of the sentence’s semantic content which is contained in the text. We present results on the Recognizing Textual Entailment dataset (Dagan et al., 2005), (...) and show that our approach outperforms Bag- Of-Words and TF-IDF models. (shrink)

Web legal information retrieval systems need the capability to reason with the knowledge modeled by legal ontologies. Using this knowledge it is possible to represent and to make inferences about the semantic content of legal documents. In this paper a methodology for applying NLP techniques to automatically create a legal ontology is proposed. The ontology is defined in the OWL semantic web language and it is used in a logic programming framework, EVOLP+ISCO, to allow users to query the semantic content (...) of the documents. ISCO allows an easy and efficient integration of declarative, object-oriented and constraint-based programming techniques with the capability to create connections with external databases. EVOLP is a dynamic logic programming framework allowing the definition of rules for actions and events. An application of the proposed methodology to the legal web information retrieval system of the Portuguese Attorney General’s Office is described. (shrink)

Hans Kelsen's legal philosophy and legal theory is regarded by many in the field as the most influential theory in this century. This volume makes available some of the best work extant on Kelsens' theory, including papers newly translated into English. It covers topics such as competing philosophical positons on the nature of law, legal validity, legal powers, and the unity of municipal and international law, as well as shedding light on Kelsen's intellectual milieu and his intellectual debts.