activity
20132018
most citedImproved bounds on sample size for implicit matrix trace estimators

70 citations · 445 across the 17 of their papers we have counts for

collaborators

19 papers

cs.LG2018★ 5 cited

GPU Accelerated Sub-Sampled Newton's Method

Sudhir B. Kylasa, Farbod Roosta-Khorasani, Michael W. Mahoney +1

First order methods, which solely rely on gradient information, are commonly used in diverse machine learning (ML) and data analysis (DA) applications. This is attributed to the si…

math.OC2018★ 28 cited

Inexact Non-Convex Newton-Type Methods

Zhewei Yao, Peng Xu, Farbod Roosta-Khorasani +1

For solving large-scale non-convex problems, we propose inexact variants of trust region and adaptive cubic regularization methods, which, to increase efficiency, incorporate vario…

stat.ML2018★ 1 cited

Out-of-sample extension of graph adjacency spectral embedding

Keith Levin, Farbod Roosta-Khorasani, Michael W. Mahoney +1

Many popular dimensionality reduction procedures have out-of-sample extensions, which allow a practitioner to apply a learned embedding to observations not seen in the initial trai…

math.OC2017★ 7 cited

Optimization Methods for Inverse Problems

Nan Ye, Farbod Roosta-Khorasani, Tiangang Cui

Optimization plays an important role in solving many inverse problems. Indeed, the task of inversion often either involves or is fully cast as a solution of an optimization problem…

cs.LG2017★ 9 cited

Invariance of Weight Distributions in Rectified MLPs

Russell Tsuchida, Farbod Roosta-Khorasani, Marcus Gallagher

An interesting approach to analyzing neural networks that has received renewed attention is to examine the equivalent kernel of the neural network. This is based on the fact that a…

cs.LG2017★ 30 cited

GIANT: Globally Improved Approximate Newton Method for Distributed Optimization

Shusen Wang, Farbod Roosta-Khorasani, Peng Xu +1

For distributed computing environment, we consider the empirical risk minimization problem and propose a distributed and communication-efficient Newton-type optimization method. At…

math.OC2017★ 34 cited

Second-Order Optimization for Non-Convex Machine Learning: An Empirical Study

Peng Xu, Farbod Roosta-Khorasani, Michael W. Mahoney

While first-order optimization methods such as stochastic gradient descent (SGD) are popular in machine learning (ML), they come with well-known deficiencies, including relatively-…

math.OC2017★ 53 cited

Newton-Type Methods for Non-Convex Optimization Under Inexact Hessian Information

Peng Xu, Fred Roosta, Michael W. Mahoney

We consider variants of trust-region and cubic regularization methods for non-convex optimization, in which the Hessian matrix is approximated. Under mild conditions on the inexact…

stat.ML2017★ 1 cited

Union of Intersections (UoI) for Interpretable Data Driven Discovery and Prediction

Kristofer E. Bouchard, Alejandro F. Bujan, Farbod Roosta-Khorasani +7

The increasing size and complexity of scientific data could dramatically enhance discovery and prediction for basic scientific applications. Realizing this potential, however, requ…

math.OC2016★ 69 cited

Sub-sampled Newton Methods with Non-uniform Sampling

Peng Xu, Jiyan Yang, Farbod Roosta-Khorasani +2

We consider the problem of finding the minimizer of a convex function of the form where a low-rank facto…

math.OC2016

FLAG n' FLARE: Fast Linearly-Coupled Adaptive Gradient Methods

Xiang Cheng, Farbod Roosta-Khorasani, Stefan Palombo +2

We consider first order gradient methods for effectively optimizing a composite objective in the form of a sum of smooth and, potentially, non-smooth functions. We present accelera…

math.OC2016★ 57 cited

Sub-Sampled Newton Methods II: Local Convergence Rates

Farbod Roosta-Khorasani, Michael W. Mahoney

Many data-fitting applications require the solution of an optimization problem involving a sum of large number of functions of high dimensional parameter. Here, we consider the pro…

math.OC2016★ 59 cited

Sub-Sampled Newton Methods I: Globally Convergent Algorithms

Farbod Roosta-Khorasani, Michael W. Mahoney

Large scale optimization problems are ubiquitous in machine learning and data analysis and there is a plethora of algorithms for solving such problems. Many of these algorithms emp…

math.OC2016

Variational Perspective on Local Graph Clustering

Kimon Fountoulakis, Farbod Roosta-Khorasan, Julian Shun +2

Modern graph clustering applications require the analysis of large graphs and this can be computationally expensive. In this regard, local spectral graph clustering methods aim to…

math.PR2016★ 5 cited

Schur properties of convolutions of gamma random variables

Farbod Roosta-Khorasani, Gabor J. Szekely

Sufficient conditions for comparing the convolutions of heterogeneous gamma random variables in terms of the usual stochastic order are established. Such comparisons are characteri…

math.NA2014

Algorithms that satisfy a stopping criterion, probably

Uri Ascher, Farbod Roosta-Khorasani

Iterative numerical algorithms are typically equipped with a stopping criterion, where the iteration process is terminated when some error or misfit measure is deemed to be below a…

math.NA2014★ 12 cited

Assessing stochastic algorithms for large scale nonlinear least squares problems using extremal probabilities of linear combinations of gamma random variables

Farbod Roosta-Khorasani, Gábor J. Székely, Uri Ascher

This article considers stochastic algorithms for efficiently solving a class of large scale non-linear least squares (NLS) problems which frequently arise in applications. We propo…

math.NA2013★ 5 cited

Data completion and stochastic algorithms for PDE inversion problems with many measurements

Farbod Roosta-Khorasani, Kees van den Doel, Uri Ascher

Inverse problems involving systems of partial differential equations (PDEs) with many measurements or experiments can be very expensive to solve numerically. In a recent paper we e…

math.NA2013★ 70 cited

Improved bounds on sample size for implicit matrix trace estimators

Farbod Roosta-Khorasani, Uri Ascher

This article is concerned with Monte-Carlo methods for the estimation of the trace of an implicitly given matrix whose information is only available through matrix-vector produ…