fairness

On the Resolution of Ties in Fair Convex Allocation Problems

  • Bismark Singh
    • Categories Convex and Nonsmooth Optimization, Convex Optimization Tags , , , ,

    We study the emergence of indistinguishable, but structurally distinct, allocation outcomes in convex resource allocation models. Such outcomes occur when different users receive proportionally identical allocations despite differences in initial conditions, eligibility sets, or priority weights. We formalize this behavior and analyze the structural conditions under which it arises, with a focus on fairness-oriented objectives. … Read more

    An Optimization-Based Algorithm for Fair and Calibrated Synthetic Data Generation

  • Maria Eduarda Pinheiro
  • Jan Pablo Burgard
  • João Vitor Pamplona
    • Categories Applications - OR and Management Sciences Tags , , ,

      For agent based micro simulations, as used for example for epidemiological modeling during the COVID-19 pandemic, a realistic base population is crucial. Beyond demographic variables, health-related variables should also be included. In Germany, health-related surveys are typically small in scale, which presents several challenges when generating these variables. Specifically, strongly imbalanced classes and insufficient … Read more

    Fair network design problem: an application to EV charging station capacity expansion

  • Nagisa Sugishita
  • Margarida Carvalho
    • Categories Bilevel Optimization Tags , , ,

    This study addresses the bilevel network design problem (NDP) with congestion. The upper-level decision-maker (a network designer) selects a set of arcs to add to an existing transportation network, while the lower-level decision-makers (drivers) respond by choosing routes that minimize their individual travel times, resulting in user equilibrium. In this work, we propose two novel … Read more

    Equity-promoting Integer Programming Approaches For Medical Resident Rotation Scheduling

  • Karmel S. Shehadeh
  • Shutian Li
  • Frank E. Curtis
  • Beth Hochman
    • Categories Applications - OR and Management Sciences, Integer Programming, Multi-Criteria Optimization Tags , , ,

    Motivated by our collaboration with a residency program at an academic health system, we propose new integer programming (IP) approaches for the resident-to-rotation assignment problem (RRAP). Given sets of residents, resident classes, and departments, as well as a block structure for each class, staffing needs, rotation requirements for each class, program rules, and resident vacation … Read more

    Distributionally Fair Stochastic Optimization using Wasserstein Distance

  • Ye Qing
  • Grani A. Hanasusanto
  • Weijun Xie
    • Categories Stochastic Programming Tags , ,

    A traditional stochastic program under a finite population typically seeks to optimize efficiency by maximizing the expected profits or minimizing the expected costs, subject to a set of constraints. However, implementing such optimization-based decisions can have varying impacts on individuals, and when assessed using the individuals’ utility functions, these impacts may differ substantially across demographic … Read more

    Learning Optimal and Fair Policies for Online Allocation of Scarce Societal Resources from Data Collected in Deployment

  • Bill Tang
  • Çağıl Koçyiğit
  • Eric Rice
  • Phebe Vayanos
    • Categories Applications - OR and Management Sciences Tags , , , , ,

    We study the problem of allocating scarce societal resources of different types (e.g., permanent housing, deceased donor kidneys for transplantation, ventilators) to heterogeneous allocatees on a waitlist (e.g., people experiencing homelessness, individuals suffering from end-stage renal disease, Covid-19 patients) based on their observed covariates. We leverage administrative data collected in deployment to design an online … Read more

    Democratization of Complex-Problem Solving: Toward Privacy-Aware, Transparent and Inclusive Optimization

  • Mikhail Bragin
  • Karmel S. Shehadeh
    • Categories (Mixed) Integer Linear Programming, Integer Programming Tags , , , , , ,

    Critical operations often involve stakeholders with diverse perspectives, yet centralized optimization assumes participation or private information, neither of which is a priori guaranteed. Additionally, decision-making involves discrete decisions, making optimization computationally challenging. Centralized formulations use approximations to manage complexity, often overlooking stakeholder perspectives, leading to bias. To resolve these challenges, we adopt a privacy-aware participatory-distributed … Read more

    Fair stochastic vehicle routing with partial deliveries

  • Natasja Sluijk
  • Walter Rei
  • Joris Kinable
  • Michel Gendreau
  • Tom Van Woensel
    • Categories Branch and Cut Algorithms, Stochastic Programming, Transportation Tags , , ,

    A common assumption in the models for the vehicle routing problem with stochastic demands is that all demands must be satisfied. This is achieved by including recourse actions in two-stage stochastic programming formulations or by ensuring with a high probability that all demand fits within the vehicle capacity (chance-constrained formulations). In this work, we relax … Read more

    Fair and Risk-averse Urban Air Mobility Resource Allocation Under Uncertainties

  • Luying Sun
  • Weijun Xie
    • Categories Applications - OR and Management Sciences Tags , , , ,

    Urban Air Mobility (UAM) is an emerging air transportation mode to alleviate the ground traffic burden and achieve zero direct aviation emissions. Due to the potential economic scaling effects, the UAM traffic flow is expected to increase dramatically once implemented, and its market can be substantially large. To be prepared for the era of UAM, … Read more

    Generating balanced workload allocations in hospitals

  • Pieter Smet
    • Categories (Mixed) Integer Linear Programming, Applications - OR and Management Sciences, Multi-Criteria Optimization Tags , , ,

    As pressure on healthcare systems continues to increase, it is becoming more and more important for hospitals to properly manage the high workload levels of their staff. Ensuring a balanced workload allocation between various groups of employees in a hospital has been shown to contribute considerably towards creating sustainable working conditions. However, allocating work to … Read more