Convexification of mixed-integer quadratic optimization via decision diagrams

We study mixed-integer quadratic optimization (MIQO) problems with indicator variables. We propose a unified framework, based on decision diagrams, that serves both to solve the associated optimization problems and to construct ideal conic quadratic extended formulations of the closure of the convex hull of the underlying mixed-integer set. The construction applies to arbitrary quadratics and … Read more

A Decision-Support Framework for Structuring and Reducing Large Multi-Objective Solution Sets via Clustering: An Application to Proton Therapy

This paper proposes a four-stage decision-support framework for structuring and reducing large multi-objective solution sets into compact and interpretable collections of representative alternatives. The methodology combines: (Phase 1) systematic solution generation through extended goal programming and structured preference exploration; (Phase 2) robustness-aware enrichment and profiling under weight sensitivity analysis; (Phase 3) filtering and dominance-based reduction … Read more

On the Absence of Identifiable Manifolds in Finite-Max Composite Optimization

In nonsmooth optimization, identifiable sets describe the local region eventually reached by sequences converging to a prescribed critical point. When such a set is a \(C^2\) manifold on which the objective restricts to a \(C^2\) function, it is called an identifiable manifold. Their appeal lies in what they enable: many first-order methods identify these manifolds … Read more

Online Performative Decision Making with Latent Distribution States

Many operational decisions reshape the populations they act on: routing policies alter traffic, care interventions affect health outcomes, and public programs change participation. We study online control of such decision-dependent populations when the primitive state is a distribution, actions determine both current reward and the next distribution, and the reward and transition laws are unknown. … Read more

DD-suite: A cross-platform package to build Decision Diagrams for optimization purposes

Decision diagrams (DDs) have become a powerful tool for discrete optimization, supporting a wide range of algorithms that span cut-generation procedures, decomposition methods, and specialized branch-and-bound searches. Despite this growth, their adoption remains limited, partly because most existing DD code is tailored to a specific algorithm or application and is therefore hard to reuse. We … Read more

Attainability of properly efficient points via weighted norm scalarization

We show that efficient points can be obtained with the weighted norm scalarization under assumptions less restrictive than in the existing literature. For properly efficient points with a given trade-off bound, we provide an easy-to-compute lower bound on the norm parameter that allows the approximation of the desired points within a specified tolerance. We apply … Read more

Exact Branch-and-Price Algorithm for Live Operating Room Reoptimization

Live reoptimization of operating room schedules is required to cope with disruptions such as emergency arrivals and deviations in surgery durations under strict time limits. The resulting problem can be formulated as a large-scale Resource Constrained Project Scheduling Problem (RCPSP). While exact optimization methods are attractive in this context due to their ability to provide … Read more

A Numerically-safe Branch-Price-and-Cut Algorithm for the Length-Constrained Cycle Partition Problem

The length-constrained cycle partition problem (LCCP) is a graph optimization problem in which a set of nodes must be partitioned into a minimum number of cycles. Every node is associated with a critical time and the length of every cycle must not exceed the critical time of any node in the cycle. We formulate LCCP … Read more

Convexlikeness and Supportedness in Quadratic Multiobjective Optimization

This paper studies geometric and structural properties of quadratic multiobjective optimization problems. Thereby, a multiobjective optimization problem is called convexlike if the upper image, i.e., the image set plus the nonnegative orthant, is a convex set. Moreover, we say that a feasible point is supported in case it is a minimal solution of a weighted … Read more

Approximate solution of infinite-horizon risk-sensitive Markov decision processes

Infinite-horizon risk-sensitive Markov decision processes (MDPs) under the discounted cost criterion are challenging to solve because the optimal policy may be nonstationary. Existing methods  typically reformulate the problem as a continuous-state risk-neutral MDP and rely on state discretization or value-function approximation, often without explicit stopping conditions or error bounds. In this paper, we present approximate … Read more