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Learning and inference in weighted logic with application to natural language processing
Over the past two decades, statistical machine learning approaches to natural language processing have largely replaced earlier logic-based systems. These probabilistic methods have proven to be well-suited to the ambiguity inherent in human communication. However, the shift to statistical modeling has mostly abandoned the representational advantages of logic-based approaches. For example, many language processing problems can be more meaningfully expressed in first-order logic rather than propositional logic. Unfortunately, most machine learning algorithms have been developed for propositional knowledge representations. In recent years, there have been a number of attempts to combine logical and probabilistic approaches to artificial intelligence. However, their impact on real-world applications has been limited because of serious scalability issues that arise when algorithms designed for propositional representations are applied to first-order logic representations. In this thesis, we explore approximate learning and inference algorithms that are tailored for higher-order representations, and demonstrate that this synthesis of probability and logic can significantly improve the accuracy of several language processing systems.
Culotta, Aron, "Learning and inference in weighted logic with application to natural language processing" (2008). Doctoral Dissertations Available from Proquest. AAI3325268.