Arrow Research search

Author name cluster

Thomas Pensyl

Possible papers associated with this exact author name in Arrow. This page groups case-insensitive exact name matches and is not a full identity disambiguation profile.

3 papers
1 author row

Possible papers

3

JMLR Journal 2022 Journal Article

Dependent randomized rounding for clustering and partition systems with knapsack constraints

  • David G. Harris
  • Thomas Pensyl
  • Aravind Srinivasan
  • Khoa Trinh

Clustering problems are fundamental to unsupervised learning. There is an increased emphasis on fairness in machine learning and AI; one representative notion of fairness is that no single group should be over-represented among the cluster-centers. This, and much more general clustering problems, can be formulated with “knapsack" and “partition" constraints. We develop new randomized algorithms targeting such problems, and study two in particular: multi-knapsack median and multi-knapsack center. Our rounding algorithms give new approximation and pseudo-approximation algorithms for these problems. One key technical tool, which may be of independent interest, is a new tail bound analogous to Feige (2006) for sums of random variables with unbounded variances. Such bounds can be useful in inferring properties of large networks using few samples. [abs] [ pdf ][ bib ] &copy JMLR 2022. ( edit, beta )

JMLR Journal 2019 Journal Article

Approximation Algorithms for Stochastic Clustering

  • David G. Harris
  • Shi Li
  • Thomas Pensyl
  • Aravind Srinivasan
  • Khoa Trinh

We consider stochastic settings for clustering, and develop provably-good approximation algorithms for a number of these notions. These algorithms yield better approximation ratios compared to the usual deterministic clustering setting. Additionally, they offer a number of advantages including clustering which is fairer and has better long-term behavior for each user. In particular, they ensure that every user is guaranteed to get good service (on average). We also complement some of these with impossibility results. [abs] [ pdf ][ bib ] &copy JMLR 2019. ( edit, beta )

NeurIPS Conference 2018 Conference Paper

Approximation algorithms for stochastic clustering

  • David Harris
  • Shi Li
  • Aravind Srinivasan
  • Khoa Trinh
  • Thomas Pensyl

We consider stochastic settings for clustering, and develop provably-good (approximation) algorithms for a number of these notions. These algorithms allow one to obtain better approximation ratios compared to the usual deterministic clustering setting. Additionally, they offer a number of advantages including providing fairer clustering and clustering which has better long-term behavior for each user. In particular, they ensure that every user is guaranteed to get good service (on average). We also complement some of these with impossibility results.