activity
20142021
most citedFirst-order Methods Almost Always Avoid Saddle Points

76 citations · 226 across the 9 of their papers we have counts for

collaborators

10 papers

cs.LG2021★ 4 cited

Independent Natural Policy Gradient Always Converges in Markov Potential Games

Roy Fox, Stephen McAleer, Will Overman +1

Multi-agent reinforcement learning has been successfully applied to fully-cooperative and fully-competitive environments, but little is currently known about mixed cooperative/comp…

cs.LG2021★ 25 cited

Global Convergence of Multi-Agent Policy Gradient in Markov Potential Games

Stefanos Leonardos, Will Overman, Ioannis Panageas +1

Potential games are arguably one of the most important and widely studied classes of normal form games. They define the archetypal setting of multi-agent coordination as all agent…

math.OC2019★ 4 cited

First-order methods almost always avoid saddle points: the case of vanishing step-sizes

Ioannis Panageas, Georgios Piliouras, Xiao Wang

In a series of papers \cite{LSJR16, PP17, LPP}, it was established that some of the most commonly used first order methods almost surely (under random initializations) and with ste…

stat.ML2017★ 76 cited

First-order Methods Almost Always Avoid Saddle Points

Jason D. Lee, Ioannis Panageas, Georgios Piliouras +3

We establish that first-order methods avoid saddle points for almost all initializations. Our results apply to a wide variety of first-order methods, including gradient descent, bl…

cs.GT2017★ 60 cited

Multiplicative Weights Update with Constant Step-Size in Congestion Games: Convergence, Limit Cycles and Chaos

Gerasimos Palaiopanos, Ioannis Panageas, Georgios Piliouras

The Multiplicative Weights Update (MWU) method is a ubiquitous meta-algorithm that works as follows: A distribution is maintained on a certain set, and at each step the probability…

math.DS2016★ 41 cited

Gradient Descent Only Converges to Minimizers: Non-Isolated Critical Points and Invariant Regions

Ioannis Panageas, Georgios Piliouras

Given a non-convex twice differentiable cost function f, we prove that the set of initial conditions so that gradient descent converges to saddle points where \nabla^2 f has at lea…

q-bio.PE2015

Mutation, Sexual Reproduction and Survival in Dynamic Environments

Ruta Mehta, Ioannis Panageas, Georgios Piliouras +2

A new approach to understanding evolution [Val09], namely viewing it through the lens of computation, has already started yielding new insights, e.g., natural selection under sexua…

q-bio.PE2014

The Complexity of Genetic Diversity

Ruta Mehta, Ioannis Panageas, Georgios Piliouras +1

A key question in biological systems is whether genetic diversity persists in the long run under evolutionary competition or whether a single dominant genotype emerges. Classic wor…

math.DS2014★ 15 cited

Natural Selection as an Inhibitor of Genetic Diversity: Multiplicative Weights Updates Algorithm and a Conjecture of Haploid Genetics

Ruta Mehta, Ioannis Panageas, Georgios Piliouras

In a recent series of papers a surprisingly strong connection was discovered between standard models of evolution in mathematical biology and Multiplicative Weights Updates Algorit…

cs.GT2014★ 1 cited

Average Case Performance of Replicator Dynamics in Potential Games via Computing Regions of Attraction

Ioannis Panageas, Georgios Piliouras

What does it mean to fully understand the behavior of a network of adaptive agents? The golden standard typically is the behavior of learning dynamics in potential games, where man…