Faculty

Jonathan Vi Perrie, Master’s candidate
David R. Cheriton School of Computer Science

Over the years, hit song science has been a controversial topic within music information retrieval (MIR). Researchers have debated whether an unbiased dataset can be constructed and what it means to successfully model song performance. Often classes for modelling are derived from one component of song performance, like for example, a song's peak position on some chart. 

Rahul Iyer, Master’s candidate
David R. Cheriton School of Computer Science

Social interactions in the form of discussion are an indispensable part of collaborative software development. The discussions are essential for developers to share their views and to form a strong relationship with other teammates. These discussions invoke both positive and negative emotions such as joy, love, aggression, and disgust. Additionally, developers also exhibit hidden behaviors that dictate their personality. Some developers can be supportive and open to new ideas, whereas others can be conservative. Past research has shown that the personality of the developers has a significant role in determining the success of the task they collaboratively perform.

Thursday, July 18, 2019 1:30 pm - 1:30 pm EDT (GMT -04:00)

PhD Seminar: Attention Mechanisms for Weakly Supervised Image Segmentation

Paulo Pacheco, PhD candidate
David R. Cheriton School of Computer Science

In this seminar I will discuss some of the current state-of-the-art methods for generating attention maps in weakly supervised (image level annotations) for classification tasks, aiming image segmentation inference and object localization.

Wednesday, July 17, 2019 2:00 pm - 2:00 pm EDT (GMT -04:00)

PhD Seminar: Comparing EM with GD in Mixture Models of Two Components

Guojun Zhang, PhD candidate
David R. Cheriton School of Computer Science

The expectation-maximization (EM) algorithm has been widely used in minimizing the negative log likelihood (also known as cross entropy) of mixture models. However, little is understood about the goodness of the fixed points it converges to. 

Matthew Angus, Master’s candidate
David R. Cheriton School of Computer Science

There exists wide research surrounding the detection of out of distribution sample for image classification. Safety critical applications, such as autonomous driving, would benefit from the ability to localise the unusual objects causing an image to be out of distribution. 

Wednesday, May 29, 2019 11:30 am - 11:30 am EDT (GMT -04:00)

PhD Defence: Theoretical Foundations for Efficient Clustering

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

Clustering aims to group together data instances which are similar while simultaneously separating the dissimilar instances. The task of clustering is challenging due to many factors. The most well-studied is the high computational cost. The clustering task can be viewed as an optimization problem where the goal is to minimize a certain cost function (like k-means cost or k-median cost). Not only are the minimization problems NP-Hard but often also NP-Hard to approximate (within a constant factor). There are two other major issues in clustering, namely under-specificity and noise-robustness. 

Yingluo Xun, Master’s candidate
David R. Cheriton School of Computer Science

In reinforcement learning, entropy-regularized value function (in policy space) has attracted a lot of attention recently due to its effect on smoothing the value function, and the effect on encouraging exploration. However, there is a discrepancy between the regularized objective function and the original objective function in existing methods, which would potentially result in a discrepancy between the trained policy and the optimal policy, as the policy directly depends on the value function in the reinforcement learning framework. 

Wednesday, June 26, 2019 10:00 am - 10:00 am EDT (GMT -04:00)

Master’s Thesis Presentation: Applying Fair Reward Divisions to Collaborative Work

Greg d’Eon, Master’s candidate
David R. Cheriton School of Computer Science

Collaborative crowdsourcing tasks allow workers to solve more difficult problems than they could alone, but motivating workers in these tasks is complex. In this thesis, we study how to use payments to motivate groups of crowd workers. We leverage concepts from equity theory and cooperative game theory to understand the connection between fair payments and motivation. 

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.

The key to people trusting and co-operating with artificially intelligent agents lies in their ability to display human-like emotions, according to a new study by Postdoctoral Fellow Moojan Ghafurian, Master’s candidate Neil Budnarain and Professor Jesse Hoey at the Cheriton School of Computer Science.