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Valerii Likhosherstov

18 accepted papers

2024

Learning a Fourier Transform for Linear Relative Positional Encodings in Transformers

AISTATS 2024poster

We propose a new class of linear Transformers called FourierLearner-Transformers (FLTs), which incorporate a wide range of relative positional encoding mechanisms (RPEs). These include regular RPE techniques applied for sequential data, as well as novel RPEs operating on geometric data embedded in h…

Cited by 9SourcePDFScholar
2024

Scalable Neural Network Kernels

ICLR 2024poster

We introduce the concept of scalable neural network kernels (SNNKs), the replacements of regular feedforward layers (FFLs), capable of approximating the latter, but with favorable computational properties. SNNKs effectively disentangle the inputs from the parameters of the neural network in the FFL,…

2024

UniGen: Unified Modeling of Initial Agent States and Trajectories for Generating Autonomous Driving Scenarios

ICRA 2024poster

This paper introduces UniGen, a novel approach to generating new traffic scenarios for evaluating and improving autonomous driving software through simulation. Our approach models all driving scenario elements in a unified model: the position of new agents, their initial state, and their future moti…

Cited by 3SourceScholar
2023

Adaptive Computation with Elastic Input Sequence

ICML 2023poster

Humans have the ability to adapt the type of information they use, the procedure they employ, and the amount of time they spend when solving problems. However, most standard neural networks have a fixed function type and computation budget regardless of the sample's nature or difficulty. Adaptivity…

2023

Dense-Exponential Random Features: Sharp Positive Estimators of the Gaussian Kernel

NeurIPS 2023poster

The problem of efficient approximation of a linear operator induced by the Gaussian or softmax kernel is often addressed using random features (RFs) which yield an unbiased approximation of the operator's result. Such operators emerge in important applications ranging from kernel methods to efficien…

Cited by 2SourcePDFScholar
2023

Efficient Graph Field Integrators Meet Point Clouds

ICML 2023poster

We present two new classes of algorithms for efficient field integration on graphs encoding point cloud data. The first class, $\mathrm{SeparatorFactorization}$ (SF), leverages the bounded genus of point cloud mesh graphs, while the second class, $\mathrm{RFDiffusion}$ (RFD), uses popular $\epsilon$…

2023

On the Expressive Flexibility of Self-Attention Matrices

AAAI 2023technical

Transformer networks are able to capture patterns in data coming from many domains (text, images, videos, proteins, etc.) with little or no change to architecture components. We perform a theoretical analysis of the core component responsible for signal propagation between elements, i.e. the self-at…

Cited by 8SourcePDFScholar
2022

Chefs' Random Tables: Non-Trigonometric Random Features

NeurIPS 2022accept

We introduce chefs' random tables (CRTs), a new class of non-trigonometric random features (RFs) to approximate Gaussian and softmax kernels. CRTs are an alternative to standard random kitchen sink (RKS) methods, which inherently rely on the trigonometric maps. We present variants of CRTs where RFs…

2022

From block-Toeplitz matrices to differential equations on graphs: towards a general theory for scalable masked Transformers

ICML 2022spotlight

In this paper we provide, to the best of our knowledge, the first comprehensive approach for incorporating various masking mechanisms into Transformers architectures in a scalable way. We show that recent results on linear causal attention (Choromanski et al., 2021) and log-linear RPE-attention (Luo…

2022

Hybrid Random Features

ICLR 2022poster

We propose a new class of random feature methods for linearizing softmax and Gaussian kernels called hybrid random features (HRFs) that automatically adapt the quality of kernel estimation to provide most accurate approximation in the defined regions of interest. Special instantiations of HRFs lead…

2021

CWY Parametrization: a Solution for Parallelized Optimization of Orthogonal and Stiefel Matrices

AISTATS 2021poster

We introduce an efficient approach for optimization over orthogonal groups on highly parallel computation units such as GPUs or TPUs. As in earlier work, we parametrize an orthogonal matrix as a product of Householder reflections. However, to overcome low parallelization capabilities of computing Ho…

Cited by 2SourcePDFScholar
2021

Debiasing a First-order Heuristic for Approximate Bi-level Optimization

ICML 2021spotlight

Approximate bi-level optimization (ABLO) consists of (outer-level) optimization problems, involving numerical (inner-level) optimization loops. While ABLO has many applications across deep learning, it suffers from time and memory complexity proportional to the length $r$ of its inner optimization l…

2021

Rethinking Attention with Performers

ICLR 2021oral

We introduce Performers, Transformer architectures which can estimate regular (softmax) full-rank-attention Transformers with provable accuracy, but using only linear (as opposed to quadratic) space and time complexity, without relying on any priors such as sparsity or low-rankness. To approximate s…

2021

Sub-Linear Memory: How to Make Performers SLiM

NeurIPS 2021poster

Transformer architectures have become very popular yet the original implementation requires $O(L^2)$ in serial time and memory as functions of input length $L$. Recent works proposed various linear self-attention mechanisms, scaling only as $O(L)$ for serial computation. We conduct a thorough compl…

2020

Ode to an ODE

NeurIPS 2020poster

We present a new paradigm for Neural ODE algorithms, called ODEtoODE, where time-dependent parameters of the main flow evolve according to a matrix flow on the orthogonal group O(d). This nested system of two flows, where the parameter-flow is constrained to lie on the compact manifold, provides sta…

Cited by 30SourcePDFScholar
2020

Stochastic Flows and Geometric Optimization on the Orthogonal Group

ICML 2020poster

We present a new class of stochastic, geometrically-driven optimization algorithms on the orthogonal group O(d) and naturally reductive homogeneous manifolds obtained from the action of the rotation group SO(d). We theoretically and experimentally demonstrate that our methods can be applied in vario…

Cited by 9SourcePDFScholar