Applications – OR and Management Sciences

The Minimization of the Weighted Completion Time Variance in a Single Machine: A Specialized Cutting-Plane Approach

  • Stefano Nasini
  • Rabia Nessah
    • Categories (Mixed) Integer Linear Programming, Branch and Cut Algorithms, Scheduling

    This study addresses the problem of minimizing the weighted completion time variance (WCTV) in single-machine scheduling. Unlike the unweighted version, which has been extensively studied, the weighted variant introduces unique challenges due to the absence of theoretical properties that could guide the design of efficient algorithms. We propose a mathematical programming framework based on a … Read more

    Anesthesiologist Scheduling with Handoffs: A Combined Approach of Optimization and Human Factors

  • Ankit Bansal
  • Osman Y. Ozaltin
    • Categories Integer Programming, Scheduling, Stochastic Programming

    We present a two-stage stochastic programming model for optimizing anesthesiologist schedules, explicitly accounting for uncertainty in surgery durations and anesthesiologist handoffs. To inform model design, we conducted an online survey at our partner institution to identify key factors affecting the quality of intraoperative anesthesiologist handoffs. Insights from the survey results are incorporated into the model, … Read more

    Optimal personnel scheduling in hospital pharmacies considering management and operators priorities

  • Eduardo Souza
  • Walton P. Coutinho
  • Luciano Costa
    • Categories (Mixed) Integer Linear Programming, Applications - OR and Management Sciences, Scheduling Tags , ,

    In this paper, we address the problem of allocating and scheduling employees for work shifts in the pharmacy sector of a private hospital. To tackle this issue, we introduce the pharmacy staff scheduling problem (PSSP) in the literature. To solve the problem, we propose a mixed-integer programming formulation that considers various aspects, such as the … Read more

    Teaching Statistics Using Facility Location Modeling: A Course-based Undergraduate Research Experience

  • Abel Sapirstein
  • Lauren Steimle
    • Categories Applications - OR and Management Sciences, Other Topics Tags , , , ,

    There is a growing need to expand and strengthen the industrial engineering/operations research workforce. Undergraduate research experiences are an effective way to build in-demand skills and to attract people to science, technology, engineering, and mathematics fields, such as industrial engineering/operations research. However, the traditional apprenticeship model of an undergraduate research experience limits the number of … Read more

    Random-Restart Best-Response Dynamics for Large-Scale Integer Programming Games and Their Applications

  • Hyunwoo Lee
  • Robert Hildebrand
  • Wenbo Cai
  • I. Esra Buyuktahtakin Toy
    • Categories (Mixed) Integer Linear Programming, Applications - OR and Management Sciences, Game Theory Tags , , ,

    This paper presents scalable algorithms for computing pure Nash equilibria (PNEs) in large-scale integer programming games (IPGs), where existing exact methods typically handle only small numbers of players. Motivated by a county-level aquatic invasive species (AIS) prevention problem with 84 decision makers, we develop and analyze random-restart best-response dynamics (RR-BRD), a randomized search framework for … Read more

    Identifying Regions Vulnerable to Obstetric Unit Closures using Facility Location Modeling with Patient Behavior

  • Meghan Meredith
  • Lauren Steimle
    • Categories Applications - OR and Management Sciences Tags , , , ,

    Limited geographic access to obstetric care prevents some pregnant people from receiving timely and risk-appropriate services. This challenge is especially acute in rural areas, where rural residents often travel far distances to obstetric care. Furthermore, obstetric access is worsening due to the growing number of closures of rural hospitals’ obstetric units, often due to financial … 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

    Two approaches to piecewise affine approximation

  • Nadezda Sukhorukova
    • Categories Applications - OR and Management Sciences, Approximation Algorithms, Data-Mining Tags , , ,

    The problem of approximation by piecewise affine functions has been studied for several decades (least squares and uniform approximation). If the location of switches from one affine piece to another (knots for univariate approximation) is known the problem is convex and there are several approaches to solve this problem. If the location of such switches … Read more

    Data-Driven Multistage Scheduling Optimization for Refinery Production under Uncertainty: Systematic Framework, Modeling Approach, and Application Analysis

  • Biao Han
    • Categories Control Applications, Scheduling, Stochastic Programming Tags , , , , , , ,

    The widespread existence of various uncertainties makes the inherently complex refinery production scheduling problem even more challenging. To address this issue, this paper proposes a viable systematic data-driven multistage scheduling optimization framework and develops a corresponding structured modeling methodology. Under this paradigm, unit-level advanced control and plant-level intelligent scheduling are coordinated to jointly deal with … Read more

    Mixed-Feature Logistic Regression Robust to Distribution Shifts

  • Qingshi Sun
  • Nathan Justin
  • Andrés Gómez
  • Phebe Vayanos
    • Categories Applications - OR and Management Sciences, Integer Programming, Robust Optimization Tags , , ,

    Logistic regression models are widely used in the social and behavioral sciences and in high-stakes domains, due to their simplicity and interpretability properties. At the same time, such domains are permeated by distribution shifts, where the distribution generating the data changes between training and deployment. In this paper, we study a distributionally robust logistic regression … Read more