Publications

Towards Detecting Contextual Real-Time Toxicity for In-Game Chat

Zachary Yang

Nicolas Grenon-Godbout

Real-time toxicity detection in online environments poses a significant challenge, due to the increasing prevalence of social media and gami… (see more)ng platforms. We introduce ToxBuster, a simple and scalable model that reliably detects toxic content in real-time for a line of chat by including chat history and metadata. ToxBuster consistently outperforms conventional toxicity models across popular multiplayer games, including Rainbow Six Siege, For Honor, and DOTA 2. We conduct an ablation study to assess the importance of each model component and explore ToxBuster's transferability across the datasets. Furthermore, we showcase ToxBuster's efficacy in post-game moderation, successfully flagging 82.1% of chat-reported players at a precision level of 90.0%. Additionally, we show how an additional 6% of unreported toxic players can be proactively moderated.

2023-01-01

EMNLP (Findings) (published)

doi.org

openreview.net

Towards Learning to Imitate from a Single Video Demonstration

Glen Berseth

Florian Golemo

Chris Pal

Agents that can learn to imitate given video observation -- \emph{without direct access to state or action information} are more applicable … (see more)to learning in the natural world. However, formulating a reinforcement learning (RL) agent that facilitates this goal remains a significant challenge. We approach this challenge using contrastive training to learn a reward function comparing an agent's behaviour with a single demonstration. We use a Siamese recurrent neural network architecture to learn rewards in space and time between motion clips while training an RL policy to minimize this distance. Through experimentation, we also find that the inclusion of multi-task data and additional image encoding losses improve the temporal consistency of the learned rewards and, as a result, significantly improves policy learning. We demonstrate our approach on simulated humanoid, dog, and raptor agents in 2D and a quadruped and a humanoid in 3D. We show that our method outperforms current state-of-the-art techniques in these environments and can learn to imitate from a single video demonstration.

arxiv.org

Towards Reliable Neural Specifications

Chuqin Geng

Nham Le

Xiaojie Xu

Zhaoyue Wang

Arie Gurfinkel

Xujie Si

2023-01-01

ICML (published)

proceedings.mlr.press

openreview.net

Towards Reliable Neural Specifications

Chuqin Geng

Nham Le

Xiaojie Xu

Zhaoyue Wang

Arie Gurfinkel

Xujie Si

2023-01-01

ICML (published)

openreview.net

TrafficVis: Visualizing Organized Activity and Spatio-Temporal Patterns for Detecting and Labeling Human Trafficking

Catalina Vajiac

Duen Horng Chau

Andreas Olligschlaeger

Rebecca Mackenzie

Pratheeksha Nair

Meng-Chieh Lee

Yifei Li

Namyong Park

Reihaneh Rabbany

Christos Faloutsos

Law enforcement and domain experts can detect human trafficking (HT) in online escort websites by analyzing suspicious clusters of connected… (see more) ads. How can we explain clustering results intuitively and interactively, visualizing potential evidence for experts to analyze? We present TrafficVis, the first interface for cluster-level HT detection and labeling. Developed through months of participatory design with domain experts, TrafficVis provides coordinated views in conjunction with carefully chosen backend algorithms to effectively show spatio-temporal and text patterns to a wide variety of anti-HT stakeholders. We build upon state-of-the-art text clustering algorithms by incorporating shared metadata as a signal of connected and possibly suspicious activity, then visualize the results. Domain experts can use TrafficVis to label clusters as HT, or other, suspicious, but non-HT activity such as spam and scam, quickly creating labeled datasets to enable further HT research. Through domain expert feedback and a usage scenario, we demonstrate TRAFFICVIS's efficacy. The feedback was overwhelmingly positive, with repeated high praises for the usability and explainability of our tool, the latter being vital for indicting possible criminals.

2023-01-01

IEEE Transactions on Visualization and Computer Graphics (published)

doi.org

Transposable elements regulate thymus development and function 1

Jean-David Larouche

Céline M. Laumont

Assya Trofimov

Krystel Vincent

Leslie Hesnard

Sylvie Brochu

Caroline Côté

Juliette Humeau

Eric Bonneil

Joël Lanoix

Chantal Durette

Patrick Gendron

Jean-Philippe Laverdure

Ellen Rothman Richie

Sébastien Lemieux

Pierre Thibault

Claude Perreault

21 Transposable elements (TE) are repetitive sequences representing ~45% of the human and mouse genomes 22 and are highly expressed by medul… (see more)lary thymic epithelial cells (mTEC). In this study, we investigated the 23 role of transposable elements (TE), which are highly expressed by medullary thymic epithelial cells 24 (mTEC), on T-cell development in the thymus. We performed multi-omic analyses of TEs in human and 25 mouse thymic cells to elucidate their role in T cell development. We report that TE expression in the 26 human thymus is high and shows extensive ageand cell lineage-related variations. TEs interact with 27 multiple transcription factors in all cell types of the human thymus. Two cell types express particularly 28 broad TE repertoires: mTECs and plasmacytoid dendritic cells (pDC). In mTECs, TEs interact with 29 transcription factors essential for mTEC development and function (e.g., PAX1 and RELB) and generate 30 MHC-I-associated peptides implicated in thymocyte education. Notably, AIRE, FEZF2, and CHD4 31 regulate non-redundant sets of TEs in murine mTECs. Human thymic pDCs homogenously express large 32 numbers of TEs that lead to the formation of dsRNA, triggering RIG-I and MDA5 signaling and 33 explaining why thymic pDCs constitutively secrete IFN ɑ/β. This study illustrates the diversity of 34 interactions between TEs and the adaptive immune system. TEs are genetic parasites, and the two thymic 35 cell types most affected by TEs (mTEcs and pDCs) are essential to establishing central T-cell tolerance. 36 Therefore, we propose that the orchestration of TE expression in thymic cells is critical to prevent 37 autoimmunity in vertebrates. 38

2023-01-01

(published)

www.semanticscholar.org

Transposable elements regulate thymus development and function 1

Jean-David Larouche

Céline M. Laumont

Assya Trofimov

Krystel Vincent

Leslie Hesnard

Sylvie Brochu

Caroline Côté

Juliette Humeau

Eric Bonneil

Joël Lanoix

Chantal Durette

Patrick Gendron

Jean-Philippe Laverdure

Ellen Rothman Richie

Sébastien Lemieux

Pierre Thibault

Claude Perreault

21 Transposable elements (TE) are repetitive sequences representing ~45% of the human and mouse genomes 22 and are highly expressed by medul… (see more)lary thymic epithelial cells (mTEC). In this study, we investigated the 23 role of transposable elements (TE), which are highly expressed by medullary thymic epithelial cells 24 (mTEC), on T-cell development in the thymus. We performed multi-omic analyses of TEs in human and 25 mouse thymic cells to elucidate their role in T cell development. We report that TE expression in the 26 human thymus is high and shows extensive ageand cell lineage-related variations. TEs interact with 27 multiple transcription factors in all cell types of the human thymus. Two cell types express particularly 28 broad TE repertoires: mTECs and plasmacytoid dendritic cells (pDC). In mTECs, TEs interact with 29 transcription factors essential for mTEC development and function (e.g., PAX1 and RELB) and generate 30 MHC-I-associated peptides implicated in thymocyte education. Notably, AIRE, FEZF2, and CHD4 31 regulate non-redundant sets of TEs in murine mTECs. Human thymic pDCs homogenously express large 32 numbers of TEs that lead to the formation of dsRNA, triggering RIG-I and MDA5 signaling and 33 explaining why thymic pDCs constitutively secrete IFN ɑ/β. This study illustrates the diversity of 34 interactions between TEs and the adaptive immune system. TEs are genetic parasites, and the two thymic 35 cell types most affected by TEs (mTEcs and pDCs) are essential to establishing central T-cell tolerance. 36 Therefore, we propose that the orchestration of TE expression in thymic cells is critical to prevent 37 autoimmunity in vertebrates. 38

2023-01-01

(published)

www.semanticscholar.org

Trophic interaction models predict interactions across space, not food webs.

Dominique Caron

Ulrich Brose

Miguel Lurgi

F. Guillaume Blanchet

Dominique Gravel

Laura J. Pollock

Aim: Trophic interactions are central to our understanding of essential ecosystem functions as well as their stability. Predicting these int… (see more)eractions has become increasingly common due to the lack of empirical data on trophic interactions for most taxa in most ecosystems. We aim to determine how far and accurately trophic interaction models extrapolate to new communities both in terms of pairwise predator-prey interactions and higher level food web attributes (i.e., species position, food web-level properties).

2023-01-01

(published)

www.semanticscholar.org

Ultrastructure Analysis of Cardiomyocytes and Their Nuclei

Tabish A Syed

Yanan Wang

Drisya Dileep

Minhajuddin Sirajuddin

Kaleem Siddiqi

2023-01-01

Functional Imaging and Modeling of the Heart (published)

doi.org