Publications

Adaptive Exploration for Data-Efficient General Value Function Evaluations
Arushi Jain
Josiah P. Hanna
General Value Functions (GVFs) (Sutton et al, 2011) are an established way to represent predictive knowledge in reinforcement learning. Each… (voir plus) GVF computes the expected return for a given policy, based on a unique pseudo-reward. Multiple GVFs can be estimated in parallel using off-policy learning from a single stream of data, often sourced from a fixed behavior policy or pre-collected dataset. This leaves an open question: how can behavior policy be chosen for data-efficient GVF learning? To address this gap, we propose GVFExplorer, which aims at learning a behavior policy that efficiently gathers data for evaluating multiple GVFs in parallel. This behavior policy selects actions in proportion to the total variance in the return across all GVFs, reducing the number of environmental interactions. To enable accurate variance estimation, we use a recently proposed temporal-difference-style variance estimator. We prove that each behavior policy update reduces the mean squared error in the summed predictions over all GVFs. We empirically demonstrate our method's performance in both tabular representations and nonlinear function approximation.
ConceptGraphs: Open-Vocabulary 3D Scene Graphs for Perception and Planning
Qiao Gu
Alihusein Kuwajerwala
Sacha Morin
Krishna Murthy
Bipasha Sen
Aditya Agarwal
Corban Rivera
William Paul
Kirsty Ellis
Rama Chellappa
Chuang Gan
Celso M de Melo
Joshua B. Tenenbaum
Antonio Torralba
Florian Shkurti
For robots to perform a wide variety of tasks, they require a 3D representation of the world that is semantically rich, yet compact and effi… (voir plus)cient for task-driven perception and planning. Recent approaches have attempted to leverage features from large vision-language models to encode semantics in 3D representations. However, these approaches tend to produce maps with per-point feature vectors, which do not scale well in larger environments, nor do they contain semantic spatial relationships between entities in the environment, which are useful for downstream planning. In this work, we propose ConceptGraphs, an open-vocabulary graph-structured representation for 3D scenes. ConceptGraphs is built by leveraging 2D foundation models and fusing their output to 3D by multi-view association. The resulting representations generalize to novel semantic classes, without the need to collect large 3D datasets or finetune models. We demonstrate the utility of this representation through a number of downstream planning tasks that are specified through abstract (language) prompts and require complex reasoning over spatial and semantic concepts. (Project page: https://concept-graphs.github.io/ Explainer video: https://youtu.be/mRhNkQwRYnc )
Divergent Creativity in Humans and Large Language Models
Antoine Bellemare-Pepin
Franccois Lespinasse
Philipp Thölke
Yann Harel
Jay A. Olson
Karim Jerbi CoCo Lab
Psychology Department
U. Montr'eal
Montreal
Qc
Canada
Music department
C. University
Sociology
Anthropology department
Mila
Departmentof Psychology
University of Toronto Mississauga … (voir 5 de plus)
Mississauga
On
Department of Computer Science
Operations Research
Unique Center
The recent surge in the capabilities of Large Language Models (LLMs) has led to claims that they are approaching a level of creativity akin … (voir plus)to human capabilities. This idea has sparked a blend of excitement and apprehension. However, a critical piece that has been missing in this discourse is a systematic evaluation of LLM creativity, particularly in comparison to human divergent thinking. To bridge this gap, we leverage recent advances in creativity science to build a framework for in-depth analysis of divergent creativity in both state-of-the-art LLMs and a substantial dataset of 100,000 humans. We found evidence suggesting that LLMs can indeed surpass human capabilities in specific creative tasks such as divergent association and creative writing. Our quantitative benchmarking framework opens up new paths for the development of more creative LLMs, but it also encourages more granular inquiries into the distinctive elements that constitute human inventive thought processes, compared to those that can be artificially generated.
GAGE: Genetic Algorithm-Based Graph Explainer for Malware Analysis
Mohd Saqib
Philippe Charland
Andrew Walenstein
Malware analysts often prefer reverse engineering using Call Graphs, Control Flow Graphs (CFGs), and Data Flow Graphs (DFGs), which involves… (voir plus) the utilization of black-box Deep Learning (DL) models. The proposed research introduces a structured pipeline for reverse engineering-based analysis, offering promising results compared to state-of-the-art methods and providing high-level interpretability for malicious code blocks in subgraphs. We propose the Canonical Executable Graph (CEG) as a new representation of Portable Executable (PE) files, uniquely incorporating syntactical and semantic information into its node embeddings. At the same time, edge features capture structural aspects of PE files. This is the first work to present a PE file representation encompassing syntactical, semantic, and structural characteristics, whereas previous efforts typically focused solely on syntactic or structural properties. Furthermore, recognizing the limitations of existing graph explanation methods within Explainable Artificial Intelligence (XAI) for malware analysis, primarily due to the specificity of malicious files, we introduce Genetic Algorithm-based Graph Explainer (GAGE). GAGE operates on the CEG, striving to identify a precise subgraph relevant to predicted malware families. Through experiments and comparisons, our proposed pipeline exhibits substantial improvements in model robustness scores and discriminative power compared to the previous benchmarks. Furthermore, we have successfully used GAGE in practical applications on real-world data, producing meaningful insights and interpretability. This research offers a robust solution to enhance cybersecurity by delivering a transparent and accurate understanding of malware behaviour. Moreover, the proposed algorithm is specialized in handling graph-based data, effectively dissecting complex content and isolating influential nodes.
Globally Stable Neural Imitation Policies
Amin Abyaneh
Mariana Sosa Guzmán
TEMPLATES: Characterization of a Merger in the Dusty Lensing SPT0418-47 System
Jared Cathey
Anthony H. Gonzalez
Sidney Lower
Kedar A. Phadke
Justin Spilker
Manuel Aravena
Matthew Bayliss
Jack E. Birkin
Simon Birrer
Scott Chapman
Håkon Dahle
Christopher C. Hayward
Ryley Hill
Taylor A. Hutchison
Keunho J. Kim
Guillaume Mahler
Daniel P. Marrone
Desika Narayanan
Alexander Navarre … (voir 7 de plus)
Cassie Reuter
Jane R Rigby
Keren Sharon
Manuel Solimano
Nikolaus Sulzenauer
Joaquin Vieira
David Vizgan
The 1st International Workshop on Graph Foundation Models (GFM)
Haitao Mao
Jianan Zhao
Xiaoxin He
Zhikai Chen
Qian Huang
Zhaocheng Zhu
Micheal Bronstein
Xavier Bresson
Bryan Hooi
Haiyang Zhang
Xianfeng Tang
Luo Chen
Jiliang Tang
An AI-Resilient Text Rendering Technique for Reading and Skimming Documents
Ziwei Gu
Kenneth Li
Jonathan K. Kummerfeld
Elena L. Glassman
ChainForge: A Visual Toolkit for Prompt Engineering and LLM Hypothesis Testing
Chelse Swoopes
Priyan Vaithilingam
Martin Wattenberg
Elena L. Glassman
Evaluating outputs of large language models (LLMs) is challenging, requiring making -- and making sense of -- many responses. Yet tools that… (voir plus) go beyond basic prompting tend to require knowledge of programming APIs, focus on narrow domains, or are closed-source. We present ChainForge, an open-source visual toolkit for prompt engineering and on-demand hypothesis testing of text generation LLMs. ChainForge provides a graphical interface for comparison of responses across models and prompt variations. Our system was designed to support three tasks: model selection, prompt template design, and hypothesis testing (e.g., auditing). We released ChainForge early in its development and iterated on its design with academics and online users. Through in-lab and interview studies, we find that a range of people could use ChainForge to investigate hypotheses that matter to them, including in real-world settings. We identify three modes of prompt engineering and LLM hypothesis testing: opportunistic exploration, limited evaluation, and iterative refinement.
Designing and Evaluating Dialogue LLMs for Co-Creative Improvised Theatre
Boyd Branch
Piotr Mirowski
Sophia Ppali
Alexandra Covaci
Social robotics researchers are increasingly interested in multi-party trained conversational agents. With a growing demand for real-world e… (voir plus)valuations, our study presents Large Language Models (LLMs) deployed in a month-long live show at the Edinburgh Festival Fringe. This case study investigates human improvisers co-creating with conversational agents in a professional theatre setting. We explore the technical capabilities and constraints of on-the-spot multi-party dialogue, providing comprehensive insights from both audience and performer experiences with AI on stage. Our human-in-the-loop methodology underlines the challenges of these LLMs in generating context-relevant responses, stressing the user interface's crucial role. Audience feedback indicates an evolving interest for AI-driven live entertainment, direct human-AI interaction, and a diverse range of expectations about AI's conversational competence and utility as a creativity support tool. Human performers express immense enthusiasm, varied satisfaction, and the evolving public opinion highlights mixed emotions about AI's role in arts.
Calibration‐free parallel transmission of the cervical, thoracic, and lumbar spinal cord at <scp>7T</scp>
Christoph S. Aigner
Manuel F. Sánchez Alarcon
Alexandre D'Astous
Eva Alonso‐Ortiz
Sebastian Schmitter
Repeat it without me: Crowdsourcing the T1 mapping common ground via the ISMRM reproducibility challenge.
Mathieu Boudreau
Agah Karakuzu
Ecem Bozkurt
Madeline Carr
Marco Castellaro
Luis Concha
Mariya Doneva
Seraina A. Dual
Alex Ensworth
Alexandru Foias
Véronique Fortier
Refaat E. Gabr
Guillaume Gilbert
Carri K. Glide‐Hurst
Matthew Grech‐Sollars
Siyuan Hu
Oscar Jalnefjord
Jorge Jovicich
Kübra Keskin … (voir 22 de plus)
Peter Koken
Anastasia Kolokotronis
Simran Kukran
Nam G. Lee
Ives R. Levesque
Bochao Li
Dan Ma
Burkhard Mädler
Nyasha G. Maforo
Jamie Near
Erick Pasaye
Alonso Ramirez‐Manzanares
Ben Statton
Christian Stehning
Stefano Tambalo
Ye Tian
Chenyang Wang
Kilian Weiss
Niloufar Zakariaei
Shuo Zhang
Ziwei Zhao
Nikola Stikov
PURPOSE T1 mapping is a widely used quantitative MRI technique, but its tissue-specific values remain inconsistent across protocols, sites, … (voir plus)and vendors. The ISMRM Reproducible Research and Quantitative MR study groups jointly launched a challenge to assess the reproducibility of a well-established inversion-recovery T1 mapping technique, using acquisition details from a seminal T1 mapping paper on a standardized phantom and in human brains. METHODS The challenge used the acquisition protocol from Barral et al. (2010). Researchers collected T1 mapping data on the ISMRM/NIST phantom and/or in human brains. Data submission, pipeline development, and analysis were conducted using open-source platforms. Intersubmission and intrasubmission comparisons were performed. RESULTS Eighteen submissions (39 phantom and 56 human datasets) on scanners by three MRI vendors were collected at 3 T (except one, at 0.35 T). The mean coefficient of variation was 6.1% for intersubmission phantom measurements, and 2.9% for intrasubmission measurements. For humans, the intersubmission/intrasubmission coefficient of variation was 5.9/3.2% in the genu and 16/6.9% in the cortex. An interactive dashboard for data visualization was also developed: https://rrsg2020.dashboards.neurolibre.org. CONCLUSION The T1 intersubmission variability was twice as high as the intrasubmission variability in both phantoms and human brains, indicating that the acquisition details in the original paper were insufficient to reproduce a quantitative MRI protocol. This study reports the inherent uncertainty in T1 measures across independent research groups, bringing us one step closer to a practical clinical baseline of T1 variations in vivo.