Group-level Fairness Maximization in Online Bipartite Matching
Document Type
Conference Proceeding
Publication Date
1-1-2022
Abstract
We consider the allocation of limited resources to heterogeneous customers who arrive in an online fashion. We would like to allocate the resources “fairly”, so that no group of customers is marginalized in terms of their overall service rate. We study whether this is possible to do so in an online fashion, and if so, what a good online allocation policy is. We model this problem using online bipartite matching under stationary arrivals, a fundamental model in the literature typically studied under the objective of maximizing the total number of customers served. We instead study the objective of maximizing the minimum service rate across all groups, and propose two notions of fairness: long-run and short-run. For these fairness objectives, we analyze how competitive online algorithms can be, in comparison to offline algorithms which know the sequence of demands in advance. For long-run fairness, we propose two online heuristics (Sampling and Pooling) which establish asymptotic optimality in different regimes (no specialized supplies, no rare demand types, or imbalanced supply/demand). By contrast, outside all of these regimes, we show that the competitive ratio of online algorithms is between 0.632 and 0.732. For short-run fairness, we show for complete bipartite graphs that the competitive ratio of online algorithms is between 0.863 and 0.942; we also derive a probabilistic rejection algorithm which is asymptotically optimal in the total demand. Depending on the overall scarcity of resources, either our Sampling or Pooling heuristics could be desirable. The most difficult situation for online allocation occurs when the total supply is just enough to serve the total demand, in which case an organization could try to make allocations offline instead. We simulate our algorithms on a public ride-hailing dataset, which both demonstrates the efficacy of our heuristics and validates our managerial insights.
Identifier
85123339768 (Scopus)
ISBN
[9781713854333]
Publication Title
Proceedings of the International Joint Conference on Autonomous Agents and Multiagent Systems Aamas
e-ISSN
15582914
ISSN
15488403
First Page
1687
Last Page
1689
Volume
3
Grant
IIS-1948157
Fund Ref
National Science Foundation
Recommended Citation
Ma, Will; Xu, Pan; and Xu, Yifan, "Group-level Fairness Maximization in Online Bipartite Matching" (2022). Faculty Publications. 3334.
https://digitalcommons.njit.edu/fac_pubs/3334