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20152026
most citedMax-Sum Diversification, Monotone Submodular Functions and Semi-metric Spaces

5 citations · 16 across the 20 of their papers we have counts for

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14 papers · 1 filter

cs.DS2025

Entrywise Approximate Solutions for SDDM Systems in Almost-Linear Time

Angelo Farfan, Mehrdad Ghadiri, Junzhao Yang

We present an algorithm that given any invertible symmetric diagonally dominant M-matrix (SDDM), i.e., a principal submatrix of a graph Laplacian, and a n…

cs.DS2025

A Tight Lower Bound for the Approximation Guarantee of Higher-Order Singular Value Decomposition

Matthew Fahrbach, Mehrdad Ghadiri

We prove that the classic approximation guarantee for the higher-order singular value decomposition (HOSVD) is tight by constructing a tensor for which HOSVD achieves an approximat…

cs.DS2025

Entrywise Approximation for Matrix Inversion and Linear Systems

Mehrdad Ghadiri, Hoai-An Nguyen, Junzhao Yang

We study the bit complexity of inverting diagonally dominant matrices, which are associated with random walk quantities such as hitting times and escape probabilities. Such quantit…

cs.DS2025

Fast Tensor Completion via Approximate Richardson Iteration

Mehrdad Ghadiri, Matthew Fahrbach, Yunbum Kook +1

We study tensor completion (TC) through the lens of low-rank tensor decomposition (TD). Many TD algorithms use fast alternating minimization methods to solve highly structured line…

cs.DS2024

Entrywise Approximate Laplacian Solving

Jingbang Chen, Mehrdad Ghadiri, Hoai-An Nguyen +2

We study the escape probability problem in random walks over graphs. Given vertices, and , the problem asks for the probability that a random walk starting at will hi…

cs.DS2024

Improving the Bit Complexity of Communication for Distributed Convex Optimization

Mehrdad Ghadiri, Yin Tat Lee, Swati Padmanabhan +3

We consider the communication complexity of some fundamental convex optimization problems in the point-to-point (coordinator) and blackboard communication models. We strengthen kno…

cs.DS2023

The Bit Complexity of Efficient Continuous Optimization

Mehrdad Ghadiri, Richard Peng, Santosh S. Vempala

We analyze the bit complexity of efficient algorithms for fundamental optimization problems, such as linear regression, -norm regression, and linear programming (LP). State-of-t…

cs.DS2023★ 2 cited

Approximately Optimal Core Shapes for Tensor Decompositions

Mehrdad Ghadiri, Matthew Fahrbach, Gang Fu +1

This work studies the combinatorial optimization problem of finding an optimal core tensor shape, also called multilinear rank, for a size-constrained Tucker decomposition. We give…

cs.DS2022★ 1 cited

Subquadratic Kronecker Regression with Applications to Tensor Decomposition

Matthew Fahrbach, Thomas Fu, Mehrdad Ghadiri

Kronecker regression is a highly-structured least squares problem , where the design matrix $\mathbf{K} = \…

cs.DS2022★ 1 cited

Constant-Factor Approximation Algorithms for Socially Fair -Clustering

Mehrdad Ghadiri, Mohit Singh, Santosh S. Vempala

We study approximation algorithms for the socially fair -clustering problem with groups, whose special cases include the socially fair -median () and socia…

cs.DS2021

Faster -Norm Regression Using Sparsity

Mehrdad Ghadiri, Richard Peng, Santosh S. Vempala

For a matrix with , we consider the dual problems of and $\min_{A^\top x=b} \|x\|_p^p,\, b\in \math…

cs.DS2021★ 2 cited

Fast Low-Rank Tensor Decomposition by Ridge Leverage Score Sampling

Matthew Fahrbach, Mehrdad Ghadiri, Thomas Fu

Low-rank tensor decomposition generalizes low-rank matrix approximation and is a powerful technique for discovering low-dimensional structure in high-dimensional data. In this pape…

cs.DS2020

A Parameterized Family of Meta-Submodular Functions

Mehrdad Ghadiri, Richard Santiago, Bruce Shepherd

Submodular function maximization has found a wealth of new applications in machine learning models during the past years. The related supermodular maximization models (submodular m…

cs.DS2019

Beyond Submodular Maximization via One-Sided Smoothness

Mehrdad Ghadiri, Richard Santiago, Bruce Shepherd

The multilinear framework has achieved the breakthrough approximation for maximizing a monotone submodular function subject to a matroid constraint. This framework has a co…