Data Science/Computational Social Science Seminar: Jiaqi Ma

Date: 
Thu, 09/12/2019 - 12:00pm to 1:00pm

3330 North Quad

A Flexible Generative Framework for Graph-based Semi-supervised Learning

Abstract

We consider a family of problems that are concerned about making predictions for the majority of unlabeled, graph-structured data samples based on a small proportion of labeled examples. Relational information among the data samples, often encoded in the graph or network structure, is shown to be helpful for these semi-supervised learning tasks. Conventional graph-based regularization methods and recent graph neural networks do not fully leverage the interrelations between the features, the graph, and the labels. We propose a flexible generative framework for graph-based semi-supervised learning, which approaches the joint distribution of the node features, labels, and the graph structure. Borrowing insights from random graph models in network science literature, this joint distribution can be instantiated using various distribution families. For the inference of missing labels, we exploit recent advances of scalable variational inference techniques to approximate the Bayesian posterior. We conduct thorough experiments on benchmark datasets for graph-based semi-supervised learning. Results show that the proposed methods outperform state-of-the-art models under most settings.

Speaker Bio

Jiaqi Ma is a 4th year PhD candidate in School of Information, University of Michigan, advised by Prof. Qiaozhu Mei. His research interests lie in machine learning and data mining. He has done work in the area of multi-task learning and graph representation learning in his PhD study and his internship at Google Brain. His work has been accepted and published in top conferences, including WWW, KDD, NeurIPS, and AAAI. Prior to UMSI, he got his B.Eng. degree from Tsinghua University.