Amortized In-Context Bayesian Posterior Estimation
Sarthak Mittal
N. L. Bracher
Priyank Jaini
Marcus Brubaker
Bayesian inference provides a natural way of incorporating prior beliefs and assigning a probability measure to the space of hypotheses. Cur… (voir plus)rent solutions rely on iterative routines like Markov Chain Monte Carlo (MCMC) sampling and Variational Inference (VI), which need to be re-run whenever new observations are available. Amortization, through conditional estimation, is a viable strategy to alleviate such difficulties and has been the guiding principle behind simulation-based inference, neural processes and in-context methods using pre-trained models. In this work, we conduct a thorough comparative analysis of amortized in-context Bayesian posterior estimation methods from the lens of different optimization objectives and architectural choices. Such methods train an amortized estimator to perform posterior parameter inference by conditioning on a set of data examples passed as context to a sequence model such as a transformer. In contrast to language models, we leverage permutation invariant architectures as the true posterior is invariant to the ordering of context examples. Our empirical study includes generalization to out-of-distribution tasks, cases where the assumed underlying model is misspecified, and transfer from simulated to real problems. Subsequently, it highlights the superiority of the reverse KL estimator for predictive problems, especially when combined with the transformer architecture and normalizing flows.
Amortized In-Context Bayesian Posterior Estimation
Sarthak Mittal
N. L. Bracher
Priyank Jaini
Marcus Brubaker
Bayesian inference provides a natural way of incorporating prior beliefs and assigning a probability measure to the space of hypotheses. Cur… (voir plus)rent solutions rely on iterative routines like Markov Chain Monte Carlo (MCMC) sampling and Variational Inference (VI), which need to be re-run whenever new observations are available. Amortization, through conditional estimation, is a viable strategy to alleviate such difficulties and has been the guiding principle behind simulation-based inference, neural processes and in-context methods using pre-trained models. In this work, we conduct a thorough comparative analysis of amortized in-context Bayesian posterior estimation methods from the lens of different optimization objectives and architectural choices. Such methods train an amortized estimator to perform posterior parameter inference by conditioning on a set of data examples passed as context to a sequence model such as a transformer. In contrast to language models, we leverage permutation invariant architectures as the true posterior is invariant to the ordering of context examples. Our empirical study includes generalization to out-of-distribution tasks, cases where the assumed underlying model is misspecified, and transfer from simulated to real problems. Subsequently, it highlights the superiority of the reverse KL estimator for predictive problems, especially when combined with the transformer architecture and normalizing flows.
FairDropout: Using Example-Tied Dropout to Enhance Generalization of Minority Groups
G'eraldin Nanfack
FairDropout: Using Example-Tied Dropout to Enhance Generalization of Minority Groups
G'eraldin Nanfack
Deep learning models frequently exploit spurious features in training data to achieve low training error, often resulting in poor generaliza… (voir plus)tion when faced with shifted testing distributions. To address this issue, various methods from imbalanced learning, representation learning, and classifier recalibration have been proposed to enhance the robustness of deep neural networks against spurious correlations. In this paper, we observe that models trained with empirical risk minimization tend to generalize well for examples from the majority groups while memorizing instances from minority groups. Building on recent findings that show memorization can be localized to a limited number of neurons, we apply example-tied dropout as a method we term FairDropout, aimed at redirecting this memorization to specific neurons that we subsequently drop out during inference. We empirically evaluate FairDropout using the subpopulation benchmark suite encompassing vision, language, and healthcare tasks, demonstrating that it significantly reduces reliance on spurious correlations, and outperforms state-of-the-art methods.
Membership Inference Risks in Quantized Models: A Theoretical and Empirical Study
Eric Aubinais
Philippe Formont
Elisabeth Gassiat
Quantizing machine learning models has demonstrated its effectiveness in lowering memory and inference costs while maintaining performance l… (voir plus)evels comparable to the original models. In this work, we investigate the impact of quantization procedures on the privacy of data-driven models, specifically focusing on their vulnerability to membership inference attacks. We derive an asymptotic theoretical analysis of Membership Inference Security (MIS), characterizing the privacy implications of quantized algorithm weights against the most powerful (and possibly unknown) attacks. Building on these theoretical insights, we propose a novel methodology to empirically assess and rank the privacy levels of various quantization procedures. Using synthetic datasets, we demonstrate the effectiveness of our approach in assessing the MIS of different quantizers. Furthermore, we explore the trade-off between privacy and performance using real-world data and models in the context of molecular modeling.
Membership Inference Risks in Quantized Models: A Theoretical and Empirical Study
Eric Aubinais
Philippe Formont
Elisabeth Gassiat
Quantizing machine learning models has demonstrated its effectiveness in lowering memory and inference costs while maintaining performance l… (voir plus)evels comparable to the original models. In this work, we investigate the impact of quantization procedures on the privacy of data-driven models, specifically focusing on their vulnerability to membership inference attacks. We derive an asymptotic theoretical analysis of Membership Inference Security (MIS), characterizing the privacy implications of quantized algorithm weights against the most powerful (and possibly unknown) attacks. Building on these theoretical insights, we propose a novel methodology to empirically assess and rank the privacy levels of various quantization procedures. Using synthetic datasets, we demonstrate the effectiveness of our approach in assessing the MIS of different quantizers. Furthermore, we explore the trade-off between privacy and performance using real-world data and models in the context of molecular modeling.
Outsourced diffusion sampling: Efficient posterior inference in latent spaces of generative models
Siddarth Venkatraman
Mohsin Hasan
Minsu Kim
Luca Scimeca
Marcin Sendera
Nikolay Malkin
Any well-behaved generative model over a variable …
Overcoming Political Upheaval to Deliver Pediatric Surgical Care in Afghanistan: A Prospective Analysis of the First 1000 Procedures.
Dunya Moghul
Phillip J Hsu
Emma Bryce
Yalda Obaidy
Zane Hellman
Ajmal Sherzad
Maija Cheung
BACKGROUND Pediatric surgical care is limited in Afghanistan. Few details are known about the state of pediatric surgery in Afghanistan. We … (voir plus)explore the impact of a newly installed pediatric operating room by a children's charity on the provision of pediatric surgery in Afghanistan. STUDY DESIGN Following the opening in March 2023 of the new KidsOR operating room at Ataturk Hospital in Kabul, Afghanistan, perioperative clinical data was prospectively collected until December 2023. All children (age 14 years) undergoing surgical procedures were included in a REDCap database, and descriptive analyses were performed. RESULTS 1,014 opera
A physics-based data-driven model for CO$_2$ gas diffusion electrodes to drive automated laboratories
Ivan Grega
F'elix Therrien
Abhishek Soni
Karry Ocean
Kevan Dettelbach
Ribwar Ahmadi
Mehrdad Mokhtari
C. Berlinguette
The electrochemical reduction of atmospheric CO…
Using Image-based AI for insect monitoring and conservation - InsectAI COST Action
Tom August
Mario Balzan
Paul Bodesheim
Gunnar Brehm
Lisette Cantú-Salazar
Sílvia Castro
Joseph Chipperfield
Guillaume Ghisbain
Alba Gomez-Segura
Jérémie Goulnik
Quentin Groom
Laurens Hogeweg
Chantal Huijbers
Andreas Kamilaris
Karolis Kazlauskis
Wouter Koch
Dimitri Korsch
João Loureiro
Youri Martin
Angeliki Martinou … (voir 27 de plus)
Kent McFarland
Xavier Mestdagh
Denis Michez
Charlie Outhwaite
Luca Pegoraro
Nadja Pernat
Lars Pettersson
Pavel Pipek
Cristina Preda
Tobias Roth
David Roy
Helen Roy
Veljo Runnel
Martina Sasic
Dmitry Schigel
Julie Sheard
Cecilie Svenningsen
Heliana Teixeira
Nicolas Titeux
Thomas Tscheulin
Elli Tzirkalli
Marijn van der Velde
Roel van Klink
Nicolas Vereecken
Sarah Vray
Toke Thomas Høye
RadiSeq: a single- and bulk-cell whole-genome DNA sequencing simulator for radiation-damaged cell models
Felix Mathew
Luc Galarneau
Objective To build and validate a simulation framework to perform single-cell and bulk-cell whole genome sequencing simulation of radiation-… (voir plus)exposed Monte Carlo cell models to assist radiation genomics studies. Approach Sequencing the genomes of radiation-damaged cells can provide useful insight into radiation action for radiobiology research. However, carrying out post-irradiation sequencing experiments can often be challenging, expensive, and time-consuming. Although computational simulations have the potential to provide solutions to these experimental challenges, and aid in designing optimal experiments, the absence of tools currently limits such application. Monte Carlo toolkits exist to simulate radiation exposures of cell models but there are no tools to simulate single- and bulk-cell sequencing of cell models containing radiation-damaged DNA. Therefore, we aimed to develop a Monte Carlo simulation framework to address this gap by designing a tool capable of simulating sequencing processes for radiation-damaged cells. Main Results We developed RadiSeq – a multi-threaded whole-genome DNA sequencing simulator written in C++. RadiSeq can be used to simulate Illumina sequencing of radiation-damaged cell models produced by Monte Carlo simulations. RadiSeq has been validated through comparative analysis, where simulated data were matched against experimentally obtained data, demonstrating reasonable agreement between the two. Additionally, it comes with numerous features designed to closely resemble actual whole-genome sequencing. RadiSeq is also highly customizable with a single input parameter file. Significance RadiSeq enables the research community to perform complex simulations of radiation-exposed DNA sequencing, supporting the optimization, planning, and validation of costly and time-intensive radiation biology experiments. This framework provides a powerful tool for advancing radiation genomics research.
Mol-MoE: Training Preference-Guided Routers for Molecule Generation
Diego Calanzone
Pierluca D'Oro
Recent advances in language models have enabled framing molecule generation as sequence modeling. However, existing approaches often rely on… (voir plus) single-objective reinforcement learning, limiting their applicability to real-world drug design, where multiple competing properties must be optimized. Traditional multi-objective reinforcement learning (MORL) methods require costly retraining for each new objective combination, making rapid exploration of trade-offs impractical. To overcome these limitations, we introduce Mol-MoE, a mixture-of-experts (MoE) architecture that enables efficient test-time steering of molecule generation without retraining. Central to our approach is a preference-based router training objective that incentivizes the router to combine experts in a way that aligns with user-specified trade-offs. This provides improved flexibility in exploring the chemical property space at test time, facilitating rapid trade-off exploration. Benchmarking against state-of-the-art methods, we show that Mol-MoE achieves superior sample quality and steerability.