Seminar

Wednesday, June 5, 2019 4:00 pm - 4:00 pm EDT (GMT -04:00)

PhD Seminar: Density Estimation using Sum-of-Squares Polynomial Flows

Priyank Jaini, PhD candidate
David R. Cheriton School of Computer Science

Triangular map is a recent construct in probability theory that allows one to transform any source probability density function to any target density function. Based on triangular maps, we propose a general framework for high-dimensional density estimation, by specifying one-dimensional transformations (equivalently conditional densities) and appropriate conditioner networks.

Thursday, April 25, 2019 1:00 pm - 1:00 pm EDT (GMT -04:00)

PhD Seminar: Automating the Intentional Encoding of Human-Designable Markers

Joshua Jung, PhD candidate
David R. Cheriton School of Computer Science

Recent work established that it is possible for human artists to encode information into hand-drawn markers, but it is difficult to do when simultaneously maintaining aesthetic quality. We present two methods for relieving the mental burden associated with encoding, while allowing an artist to draw as freely as possible. 

Thursday, April 11, 2019 10:30 am - 10:30 am EDT (GMT -04:00)

AI Seminar: Voting Games: Trembling Hand Equilibria

Svetlana Obraztsova
Nanyang Technological University

Traditionally, computational social choice focuses on evaluating voting rules by their resistance to strategic behaviours, and uses computational complexity as a barrier to them. In contrast, recent works (counting from 2010) take another natural approach and analyse voting scenarios from a game-theoretic perspective, viewing strategic parties as players and examining possible stable outcomes of their interaction (i.e., equilibria). The main problem of this approach is multiple unrealistic Nash equilibria. Fortunately, several refinements have been developed that allow to filter out some undesirable Nash Equilibria. 

Wednesday, March 27, 2019 4:30 pm - 4:30 pm EDT (GMT -04:00)

PhD Seminar: Semi-supervised Clustering for De-duplication

Shrinu Kushagra, PhD candidate
David R. Cheriton School of Computer Science

Data de-duplication is the task of detecting multiple records that correspond to the same real-world entity in a database. In this work, we view de-duplication as a clustering problem. We introduce a framework which we call promise correlation clustering. Given a complete graph \(G\) with the edges labeled \(0\) and \(1\), the goal is to find a clustering that minimizes the number of \(0\) edges within a cluster plus the number of \(1\) edges across different clusters (or correlation loss). The optimal clustering can also be viewed as a complete graph \(G^*\) with edges corresponding to points in the same cluster being labeled \(0\) and other edges being labeled \(1\).

Thursday, February 28, 2019 10:30 am - 10:30 am EST (GMT -05:00)

AI Seminar: Visual Question Answering and Beyond

Aishwarya Agrawal, PhD candidate
School of Interactive Computing, Georgia Tech

In this talk, I will present our work on a multi-modal AI task called Visual Question Answering (VQA) — given an image and a natural language question about the image (e.g., “What kind of store is this?”, “Is it safe to cross the street?”), the machine’s task is to automatically produce an accurate natural language answer (“bakery”, “yes”).

Tuesday, February 19, 2019 3:00 pm - 3:00 pm EST (GMT -05:00)

PhD Seminar: Modelling the Continuum of Emotions in Neural Dialogue Systems

Nabiha Asghar, PhD candidate
David R. Cheriton School of Computer Science

Most of the existing neural conversational models process natural language primarily on a lexico-syntactic level, thereby ignoring one of the most crucial components of human-to-human dialogue: its affective content. We take a step in this direction by proposing three novel ways to incorporate affective/emotional aspects into long short term memory (LSTM) encoder-decoder neural conversation models: (1) affective word embeddings, which are cognitively engineered, (2) affect-based objective functions that augment the standard cross-entropy loss, and (3) affectively diverse beam search for decoding.

Thursday, January 24, 2019 10:30 am - 10:30 am EST (GMT -05:00)

AI Seminar: Learning to Understand Entities in Text

Eunsol Choi, Paul G. Allen School of Computer Science
University of Washington

Real world entities such as people, organizations and countries play a critical role in text. Reading offers rich explicit and implicit information about these entities, such as the categories they belong to, relationships they have with other entities, and events they participate in. 

Friday, December 14, 2018 3:00 pm - 3:00 pm EST (GMT -05:00)

PhD Seminar: Progressive Memory Banks for Incremental Domain Adaptation

Nabiha Asghar, PhD candidate
David R. Cheriton School of Computer Science

We address the problem of incremental domain adaptation (IDA). We assume each domain comes one after another, and that we could only access data in the current domain. The goal of IDA is to build a unified model performing well on all the domains that we have encountered. We propose to augment a recurrent neural network (RNN) with a directly parameterized memory bank, which is retrieved by an attention mechanism at each step of RNN transition. The memory bank provides a natural way of IDA: when adapting our model to a new domain, we progressively add new slots to the memory bank, which increases the number of parameters, and thus the model capacity.