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Vlad Niculae

17 accepted papers

2026

AdaSplash-2: Faster Differentiable Sparse Attention

ICML 2026poster

Sparse attention has been proposed as a way to alleviate the quadratic cost of transformers, a central bottleneck in long-context training. A promising line of work is $\alpha$-entmax attention, a differentiable sparse alternative to softmax that enables input-dependent sparsity yet has lagged behin…

Cited by 0SourceScholar
2025

Angular Dispersion Accelerates k-Nearest Neighbors Machine Translation

EMNLP 2025

Augmenting neural machine translation with external memory at decoding time, in the form of k -nearest neighbors machine translation ( k -NN MT), is a well-established strategy for increasing translation performance. k -NN MT retrieves a set of tokens that occurred in the most similar contexts recor

2024

Sparse and Structured Hopfield Networks

ICML 2024spotlight

Modern Hopfield networks have enjoyed recent interest due to their connection to attention in transformers. Our paper provides a unified framework for sparse Hopfield networks by establishing a link with Fenchel-Young losses. The result is a new family of Hopfield-Fenchel-Young energies whose update…

2024

The Unreasonable Effectiveness of Random Target Embeddings for Continuous-Output Neural Machine Translation

NAACL 2024short

Continuous-output neural machine translation (CoNMT) replaces the discrete next-word prediction problem with an embedding prediction.The semantic structure of the target embedding space (*i.e.*, closeness of related words) is intuitively believed to be crucial. We challenge this assumption and show…

2023

DAG Learning on the Permutahedron

ICLR 2023poster

We propose a continuous optimization framework for discovering a latent directed acyclic graph (DAG) from observational data. Our approach optimizes over the polytope of permutation vectors, the so-called Permutahedron, to learn a topological ordering. Edges can be optimized jointly, or learned cond…

2023

Viewing Knowledge Transfer in Multilingual Machine Translation Through a Representational Lens

EMNLP 2023long findings

We argue that translation quality alone is not a sufficient metric for measuring knowledge transfer in multilingual neural machine translation. To support this claim, we introduce Representational Transfer Potential (RTP), which measures representational similarities between languages. We show that…

Cited by 0SourceScholar
2022

Modeling Structure with Undirected Neural Networks

ICML 2022spotlight

Neural networks are powerful function estimators, leading to their status as a paradigm of choice for modeling structured data. However, unlike other structured representations that emphasize the modularity of the problem {–} e.g., factor graphs {–} neural networks are usually monolithic mappings fr…

2021

Learning Binary Decision Trees by Argmin Differentiation

ICML 2021spotlight

We address the problem of learning binary decision trees that partition data for some downstream task. We propose to learn discrete parameters (i.e., for tree traversals and node pruning) and continuous parameters (i.e., for tree split functions and prediction functions) simultaneously using argmin…

2020

Efficient Marginalization of Discrete and Structured Latent Variables via Sparsity

NeurIPS 2020spotlight

Training neural network models with discrete (categorical or structured) latent variables can be computationally challenging, due to the need for marginalization over large or combinatorial sets. To circumvent this issue, one typically resorts to sampling-based approximations of the true marginal, r…

2020

LP-SparseMAP: Differentiable Relaxed Optimization for Sparse Structured Prediction

ICML 2020poster

Structured predictors require solving a combinatorial optimization problem over a large number of structures, such as dependency trees or alignments. When embedded as structured hidden layers in a neural net, argmin differentiation and efficient gradient computation are further required. Recently, S…

2020

Sparse and Continuous Attention Mechanisms

NeurIPS 2020spotlight

Exponential families are widely used in machine learning; they include many distributions in continuous and discrete domains (e.g., Gaussian, Dirichlet, Poisson, and categorical distributions via the softmax transformation). Distributions in each of these families have fixed support. In contrast, fo…

2019

Learning Classifiers with Fenchel-Young Losses: Generalized Entropies, Margins, and Algorithms

AISTATS 2019poster

This paper studies Fenchel-Young losses, a generic way to construct convex loss functions from a regularization function. We analyze their properties in depth, showing that they unify many well-known loss functions and allow to create useful new ones easily. Fenchel-Young losses constructed from a…

Cited by 53SourcePDFScholar
2018

SparseMAP: Differentiable Sparse Structured Inference

ICML 2018oral

Structured prediction requires searching over a combinatorial number of structures. To tackle it, we introduce SparseMAP, a new method for sparse structured inference, together with corresponding loss functions. SparseMAP inference is able to automatically select only a few global structures: it is…

2017

Multi-output Polynomial Networks and Factorization Machines

NeurIPS 2017poster

Factorization machines and polynomial networks are supervised polynomial models based on an efficient low-rank decomposition. We extend these models to the multi-output setting, i.e., for learning vector-valued functions, with application to multi-class or multi-task problems. We cast this as the pr…

Cited by 17SourcePDFScholar