papers

Publications (39)

cs.AI2026

OpenAI o1 System Card

OpenAI, :, Aaron Jaech +261

The o1 model series is trained with large-scale reinforcement learning to reason using chain of thought. These advanced reasoning capabilities provide new avenues for improving the…

cs.LG2021

Learning with User-Level Privacy

Daniel Levy, Ziteng Sun, Kareem Amin +4

We propose and analyze algorithms to solve a range of learning tasks under user-level differential privacy constraints. Rather than guaranteeing only the privacy of individual samp…

econ.GN2026

Interpolation and Prewar-Postwar Output Volatility and Shock-Persistence Debate: A Closer Look and New Results

Hashem Dezhbakhsh, Daniel Levy

It is well established that the US prewar output was more volatile and less shock persistent than the postwar output. This is often attributed to the data interpolation employed to…

econ.GN2022

Zero-Ending Prices, Cognitive Convenience, and Price Rigidity

Avichai Snir, Haipeng, Chen +1

We assess the role of cognitive convenience in the popularity and rigidity of 0 ending prices in convenience settings. Studies show that 0 ending prices are common at convenience s…

math.OC2020

Large-Scale Methods for Distributionally Robust Optimization

Daniel Levy, Yair Carmon, John C. Duchi +1

We propose and analyze algorithms for distributionally robust optimization of convex losses with conditional value at risk (CVaR) and divergence uncertainty sets. We prove t…

stat.ML2018

Generalizing Hamiltonian Monte Carlo with Neural Networks

Daniel Levy, Matthew D. Hoffman, Jascha Sohl-Dickstein

We present a general-purpose method to train Markov chain Monte Carlo kernels, parameterized by deep neural networks, that converge and mix quickly to their target distribution. Ou…

math.AP2024

Deformations of acid-mediated invasive tumors in a model with Allee effect

Paul Carter, Arjen Doelman, Peter van Heijster +4

We consider a Gatenby--Gawlinski-type model of invasive tumors in the presence of an Allee effect. We describe the construction of bistable one-dimensional traveling fronts using s…

cs.LG2025

Energy Loss Functions for Physical Systems

Sékou-Oumar Kaba, Kusha Sareen, Daniel Levy +1

Effectively leveraging prior knowledge of a system's physics is crucial for applications of machine learning to scientific domains. Previous approaches mostly focused on incorporat…

econ.GN2025

Asymmetric price adjustment over the business cycle

Daniel Levy, Haipeng, Chen +6

Studies of micro-level price datasets find more frequent small price increases than decreases, which can be explained by consumer inattention because time-constrained shoppers migh…

cs.CL2024

GPT-4 Technical Report

OpenAI, Josh Achiam, Steven Adler +278

We report the development of GPT-4, a large-scale, multimodal model which can accept image and text inputs and produce text outputs. While less capable than humans in many real-wor…

cs.LG2024

E(3)-Equivariant Mesh Neural Networks

Thuan Trang, Nhat Khang Ngo, Daniel Levy +3

Triangular meshes are widely used to represent three-dimensional objects. As a result, many recent works have address the need for geometric deep learning on 3D mesh. However, we o…

econ.GN2025

0.001% and Counting: Revisiting the Price Rounding Tax

Doron Sayag, Avichai Snir, Daniel Levy

In 1991 and 2008, Israel abolished the equivalents of 1-cent and 5-cent coins, respectively, effectively eliminating low-denomination coins and introducing rounding in cash transac…

cs.CR2018

Faster CryptoNets: Leveraging Sparsity for Real-World Encrypted Inference

Edward Chou, Josh Beal, Daniel Levy +3

Homomorphic encryption enables arbitrary computation over data while it remains encrypted. This privacy-preserving feature is attractive for machine learning, but requires signific…

econ.GN2024

Price Setting Rules, Rounding Tax, and Inattention Penalty

Doron Sayag, Avichai Snir, Daniel Levy

We study the price rounding regulation in Israel, which outlawed non-0-ending prices, forcing retailers to round 9 ending prices, which in many stores, comprised more than 60 perce…

econ.GN2024

Small Price Changes, Sales Volume, and Menu Cost

Doron Sayag, Avichai Snir, Daniel Levy

The finding of small price changes in many retail price datasets is often viewed as a puzzle. We show that a possible explanation for the presence of small price changes is related…

cs.CC2006

A polynomial-time approximation algorithm for the number of k-matchings in bipartite graphs

Shmuel Friedland, Daniel Levy

We show that the number of -matching in a given undirected graph is equal to the number of perfect matching of the corresponding graph on an even number of vertices di…

cs.LG2026

LeMat-GenBench: A Unified Evaluation Framework for Crystal Generative Models

Siddharth Betala, Samuel P. Gleason, Ali Ramlaoui +12

Generative machine learning (ML) models hold great promise for accelerating materials discovery through the inverse design of inorganic crystals, enabling an unprecedented explorat…

cond-mat.soft2009

Smectic Polymer Vesicles

Lin Jia, Amin Cao, Daniel Levy +5

Polymer vesicles are stable robust vesicles made from block copolymer amphiphiles. Recent progress in the chemical design of block copolymers opens up the exciting possibility of c…

econ.GN2022

3 Lessons from Hyperinflationary Periods

Mark Bergen, Thomas Bergen, Daniel Levy +1

Inflation is painful, for firms, customers, employees, and society. But careful study of periods of hyperinflation point to ways that firms can adapt. In particular, companies need…

cs.LG2017

Fast Amortized Inference and Learning in Log-linear Models with Randomly Perturbed Nearest Neighbor Search

Stephen Mussmann, Daniel Levy, Stefano Ermon

Inference in log-linear models scales linearly in the size of output space in the worst-case. This is often a bottleneck in natural language processing and computer vision tasks wh…

cs.AI2017

Deterministic Policy Optimization by Combining Pathwise and Score Function Estimators for Discrete Action Spaces

Daniel Levy, Stefano Ermon

Policy optimization methods have shown great promise in solving complex reinforcement and imitation learning tasks. While model-free methods are broadly applicable, they often requ…

econ.GN2024

Large Effects of Small Cues: Priming Selfish Economic Decisions

Avichai Snir, Dudi Levy, Dian Wang +2

Many experimental studies report that economics students tend to act more selfishly than students of other disciplines, a finding that received widespread public and professional a…

econ.GN2022

Potterian Economics

Daniel Levy, Avichai Snir

Recent studies in psychology and neuroscience offer systematic evidence that fictional works exert a surprisingly strong influence on readers and have the power to shape their opin…

math.OC2025

Geometry, Computation, and Optimality in Stochastic Optimization

Chen Cheng, Daniel Levy, John C. Duchi

We study computational and statistical consequences of problem geometry in stochastic and online optimization. By focusing on constraint set and gradient geometry, we characterize…

cs.LG2026

Quantitative Bounds for Sorting-Based Permutation-Invariant Embeddings

Nadav Dym, Matthias Wellershoff, Efstratios Tsoukanis +2

We study permutation-invariant embeddings of -dimensional point sets, which are defined by sorting independent one-dimensional projections of the input. Such embeddings aris…

econ.GN2025

Retail Price Ripples

Xiao Ling, Sourav Ray, Daniel Levy

Much like small ripples in a stream, which get lost in the larger waves, small changes in retail prices often fly under the radar of public perceptions, while large price changes a…

cs.CL2024

GPT-4o System Card

OpenAI, :, Aaron Hurst +416

GPT-4o is an autoregressive omni model that accepts as input any combination of text, audio, image, and video, and generates any combination of text, audio, and image outputs. It's…

cs.CL2023

Beyond the Imitation Game: Quantifying and extrapolating the capabilities of language models

Aarohi Srivastava, Abhinav Rastogi, Abhishek Rao +448

Language models demonstrate both quantitative improvement and new qualitative capabilities with increasing scale. Despite their potentially transformative impact, these new capabil…

astro-ph2010

Determining the expansion history of the universe with the three dimensional cosmic shear

Ram Brustein, Daniel Levy

We define a new observable that depends on finite redshift differences of the spin-weighted angular moments of the two point function of the three dimensional cosmic shear and on l…

cs.CL2021

Distributionally Robust Multilingual Machine Translation

Chunting Zhou, Daniel Levy, Xian Li +2

Multilingual neural machine translation (MNMT) learns to translate multiple language pairs with a single model, potentially improving both the accuracy and the memory-efficiency of…

cs.LG2021

Adapting to Function Difficulty and Growth Conditions in Private Optimization

Hilal Asi, Daniel Levy, John Duchi

We develop algorithms for private stochastic convex optimization that adapt to the hardness of the specific function we wish to optimize. While previous work provide worst-case bou…

astro-ph.CO2010

Constraining the expansion history of the universe from the red shift evolution of cosmic shear

Daniel Levy, Ram Brustein

We present a quantitative analysis of the constraints on the total equation of state parameter that can be obtained from measuring the red shift evolution of the cosmic shear. We c…

econ.GN2024

Price Gouging or Market Forces? Fairness Perceptions of Price Hikes in the Pandemic

Avichai Snir, Daniel Levy, Dudi Levy +1

We report the results of surveys we conducted in the US and Israel in 2020, a time when many prices increased following the spread of the pandemic. To assess respondents perception…

econ.GN2023

Retail Pricing Format and Rigidity of Regular Prices

Sourav Ray, Avichai Snir, Daniel Levy

We study the price rigidity of regular and sale prices, and how it is affected by pricing formats (pricing strategies). We use data from three large Canadian stores with different…

astro-ph2009

Expressing the equation of state parameter in terms of the three dimensional cosmic shear

Daniel Levy, Ram Brustein

We study the functional dependence of the spin-weighted angular moments of the two-point correlation function of the three dimensional cosmic shear on the expansion history of the…

cs.LG2026

Symmetry-Aware Generative Modeling through Learned Canonicalization

Kusha Sareen, Daniel Levy, Arnab Kumar Mondal +3

Generative modeling of symmetric densities has a range of applications in AI for science, from drug discovery to physics simulations. The existing generative modeling paradigm for…

cond-mat.mtrl-sci2025

SymmCD: Symmetry-Preserving Crystal Generation with Diffusion Models

Daniel Levy, Siba Smarak Panigrahi, Sékou-Oumar Kaba +5

Generating novel crystalline materials has the potential to lead to advancements in fields such as electronics, energy storage, and catalysis. The defining characteristic of crysta…

cs.LG2023

Using Multiple Vector Channels Improves E(n)-Equivariant Graph Neural Networks

Daniel Levy, Sékou-Oumar Kaba, Carmelo Gonzales +2

We present a natural extension to E(n)-equivariant graph neural networks that uses multiple equivariant vectors per node. We formulate the extension and show that it improves perfo…

econ.GN2025

Sticky information and price controls: Evidence from a natural experiment

Doron Sayag, Avichai Snir, Daniel Levy

We test the predictions of the sticky information model using a survey dataset by comparing shoppers accuracy in recalling the prices of regulated and comparable unregulated produc…