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Abbas Mehrabian

5 accepted papers

2024

Finding Increasingly Large Extremal Graphs with AlphaZero and Tabu Search

IJCAI 2024poster

This work proposes a new learning-to-search benchmark and uses AI to discover new mathematical knowledge related to an open conjecture of Erdos (1975) in extremal graph theory. The problem is to find graphs with a given size (number of nodes) that maximize the number of edges without having 3- or 4-…

Cited by 7SourcePDFScholar
2020

A Practical Algorithm for Multiplayer Bandits when Arm Means Vary Among Players

AISTATS 2020poster

We study a multiplayer stochastic multi-armed bandit problem in which players cannot communicate, and if two or more players pull the same arm, a collision occurs and the involved players receive zero reward. We consider the challenging heterogeneous setting, in which different arms may have differe…

Cited by 81SourcePDFScholar
2020

Old Dog Learns New Tricks: Randomized UCB for Bandit Problems

AISTATS 2020poster

We propose RandUCB, a bandit strategy that uses theoretically derived confidence intervals similar to upper confidence bound (UCB) algorithms, but akin to Thompson sampling (TS), uses randomization to trade off exploration and exploitation. In the $K$-armed bandit setting, we show that there are inf…

2018

Nearly tight sample complexity bounds for learning mixtures of Gaussians via sample compression schemes

NeurIPS 2018oral

We prove that ϴ(k d^2 / ε^2) samples are necessary and sufficient for learning a mixture of k Gaussians in R^d, up to error ε in total variation distance. This improves both the known upper bounds and lower bounds for this problem. For mixtures of axis-aligned Gaussians, we show that O(k d / ε^2) sa…

Cited by 77SourcePDFScholar