PhD Dissertation Defense by CHIA Chong Cher | Effective and Efficient Semantic Representations and Their Applications

In this presentation, we will discuss various aspects of semantic data representations, which we broadly group into two categories. First, effective semantic representations focuses on aspects generally related to the capabilities of these representations, such as task performance and interpretability. Next, efficient semantic representations encompasses aspects which generally related to the utilization of these representations, such as their storage size as well as generalizability across multiple tasks.

Our discussion revolves around two primary forms of data, textual data as well as knowledge bases. For textual data representations, we introduce a novel approach that improves efficiency through discarding representations, while limiting the impacts on downstream task effectiveness. For knowledge base representations, we explore a novel measure of node importance in knowledge graphs, and present a heuristic approach for selecting such nodes in large knowledge graphs.

We also discuss the use of semantic representations in real world applications, and propose a novel approach for the cold-start problem when training Large Language Models in the legal domain.

CHIA Chong Cher is a fifth year PhD candidate in computer science at the SMU School of Computing and Information Systems, supervised by Prof. Hady W. Lauw. His research focuses on the effectiveness and efficiency of semantic representations.