5 research outputs found
Quantum Cognitively Motivated Decision Fusion for Video Sentiment Analysis
Video sentiment analysis as a decision-making process is inherently complex,
involving the fusion of decisions from multiple modalities and the so-caused
cognitive biases. Inspired by recent advances in quantum cognition, we show
that the sentiment judgment from one modality could be incompatible with the
judgment from another, i.e., the order matters and they cannot be jointly
measured to produce a final decision. Thus the cognitive process exhibits
"quantum-like" biases that cannot be captured by classical probability
theories. Accordingly, we propose a fundamentally new, quantum cognitively
motivated fusion strategy for predicting sentiment judgments. In particular, we
formulate utterances as quantum superposition states of positive and negative
sentiment judgments, and uni-modal classifiers as mutually incompatible
observables, on a complex-valued Hilbert space with positive-operator valued
measures. Experiments on two benchmarking datasets illustrate that our model
significantly outperforms various existing decision level and a range of
state-of-the-art content-level fusion approaches. The results also show that
the concept of incompatibility allows effective handling of all combination
patterns, including those extreme cases that are wrongly predicted by all
uni-modal classifiers.Comment: The uploaded version is a preprint of the accepted AAAI-21 pape
Ranking and Retrieval under Semantic Relevance
This thesis presents a series of conceptual and empirical developments on the ranking and retrieval of candidates under semantic relevance. Part I of the thesis introduces the concept of uncertainty in various semantic tasks (such as recognizing textual entailment) in natural language processing, and the machine learning techniques commonly employed to model these semantic phenomena. A unified view of ranking and retrieval will be presented, and the trade-off between model expressiveness, performance, and scalability in model design will be discussed.
Part II of the thesis focuses on applying these ranking and retrieval techniques to text: Chapter 3 examines the feasibility of ranking hypotheses given a premise with respect to a human's subjective probability of the hypothesis happening, effectively extending the traditional categorical task of natural language inference. Chapter 4 focuses on detecting situation frames for documents using ranking methods. Then we extend the ranking notion to retrieval, and develop both sparse (Chapter 5) and dense (Chapter 6) vector-based methods to facilitate scalable retrieval for potential answer paragraphs in question answering.
Part III turns the focus to mentions and entities in text, while continuing the theme on ranking and retrieval: Chapter 7 discusses the ranking of fine-grained types that an entity mention could belong to, leading to state-of-the-art performance on hierarchical multi-label fine-grained entity typing. Chapter 8 extends the semantic relation of coreference to a cross-document setting, enabling models to retrieve from a large corpus, instead of in a single document, when resolving coreferent entity mentions