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Large Scale Machine Learning for Multi-Label and Multi-Modal Applications
PhD Thesis Proposal Defence Title: "Large Scale Machine Learning for Multi-Label and Multi-Modal Applications" by Miss Elham JEBALBAREZI SARBIJAN Abstract: Large scale machine learning deals with the learning problems for the big data sets which are too large or complex to be dealt with by traditional methods. In this work, we go through the Extreme classification problems with large number of the labels and the multimodal data integration for the predictions tasks. Extreme classification is a classification task on an extremely large number of the labels (tags). User generated labels for any type of online data can be sparing per individual user but intractably large among all users. For example, in web and document categorization, image semantic analysis, protein function detection and social network analysis, multiple outputs should be predicted, simultaneously. In these problems, modeling output label dependencies improves the output predictions. Many of the existing algorithms do not adequately address multi-label classification with label dependencies and large number of labels. In this research, we investigate multi-label classification with label dependencies and many labels. We can then solve efficiently the problem of multi-label learning with an intractably large number of interdependent labels, such as automatic tagging of Wikipedia pages. In this research, our objective is to find an efficient approach to solve the multi label classification problem by considering output space dependencies and large scale. We make several contributions to large scale multi-label learning: First, we have studied the nature of label dependencies and efficiency of the distributed multi-label learning methods. Then, we have proposed assumption-free label sampling approach to handle huge number of the labels. Finally, we have investigated and compared chain-ordered label dependency and order-free learning methods for multi-label datasets. In the second part of our large-scale challenge investigation, as most of the learning tasks around us include several sensory modalities which represent our primary channels of communication and sensation, such as vision or touch, we go through multimodal learning complexities. There are various challenges with multimodal data, from among we concentrate on the multimodal fusion which is to integrate information from two or more modalities to perform a prediction. Our aim is understanding and modulating the relative contribution of each modality in multimodal inference tasks. Moreover, we concentrate on the curse of dimensionality happening by integrating the data from several sources, and will propose some solutions for that. We make several contributions to multimodal data processing: First, we have investigated various basic fusion methods with an application to personality recognition tasks. In contrast to the previous approaches which use simple linear or concatenation approaches, we propose to generate a $(M + 1)$-way high-order dependency structure (tensor) to consider the high-order relationships between $M$ modalities and the output layer of a neural network model. Applying a modalitybased tensor factorization method, which adopts different factors for different modalities, results in removing information present in a modality that can be compensated by other modalities, with respect to model outputs. This helps to understand the relative utility of information in each modality and handle the scale issues of the problem. In addition it leads to a less complicated model with less parameters and therefore could be applied as a regularizer avoiding overfitting. Date: Wednesday, 3 June 2020 Time: 10:00am - 12:00noon Zoom Meeting: https://hkust.zoom.us/j/96784264870 Committee Members: Prof. Pascale Fung (Supervisor, ECE) Dr. Qifeng Chen (Chairperson) Dr. Ming Liu Prof. Tong Zhang **** ALL are Welcome ****