OR Seminar: Dynamic multistage scheduling for patient-centered care plans

Bahen Centre 40 St George St, Toronto, Ontario, Canada

Speaker: Adam Diamand Abstract: We investigate the scheduling practices of multistage outpatient health programs that offer care plans customized to the needs of their patients. We formulate the scheduling problem as a Markov decision process (MDP) where patients can reschedule their appointment, may fail to show up, and may even become ineligible. The MDP has […]

OR Seminar: Derivative-Free Nonconvex Stochastic Optimization with Application to an Energy Storage Problem

Bahen Centre 40 St George St, Toronto, Ontario, Canada

Speaker: Saeed Ghadimi, Princeton University Abstract In this talk, we propose and analyze derivative-free stochastic approximation algorithms for nonconvex optimization. We first propose generalization of the conditional gradient algorithm achieving a similar rate to the standard stochastic gradient algorithm (SGD) using only noisy function evaluations (zeroth-order information). For the high-dimensional setting, we explore the advantage […]

Seminar: Smart “Predict, then Optimize”

Bahen Centre 40 St George St, Toronto, Ontario, Canada

Adam Elmachtoub, Columbia University Many real-world analytics problems involve two significant challenges: prediction and optimization. Due to the typically complex nature of each challenge, the standard paradigm is predict-then-optimize. By and large, machine learning tools are intended to minimize prediction error and do not account for how the predictions will be used in the downstream […]

DiDi Lecture: AI for the Marketplace with Applications to Ride-Sharing

Bahen Centre 40 St George St, Toronto, Ontario, Canada

Abstract In this talk, we will introduce a general analytical framework for large scale data obtained from two-sided markets, especially ride-sharing platforms like DiDi. This framework integrates classical methods including Experiment Design, Causal Inference and Reinforcement Learning, with modern machine learning methods, such as Graph Convolutional Models, Deep Learning, Transfer Learning and Generative Adversarial Network. […]

OR Seminar – Adaptive design of personalized dose-finding clinical trials

Bahen Centre 40 St George St, Toronto, Ontario, Canada

Amin Khademi, Clemson University Abstract Identifying the right dose is one the most important decisions in drug development. Significant evidence has recently become available that emphasizes the role of patient covariates in optimal dose, i.e., a dose that is optimal for a patient group may be harmful for others. A key step towards personalized (precision) […]

OR Seminar – Algorithmic, combinatorial, and geometric aspects of linear optimization

Bahen Centre 40 St George St, Toronto, Ontario, Canada

Antoine Deza (McMaster University) Abstract The simplex and interior point methods are currently the most computationally successful algorithms for linear optimization. While the simplex methods follow an edge path, the interior point methods follow the central path. The algorithmic issues are closely related to the combinatorial and geometric structure of the feasible region. Focusing on the analysis […]

OR Seminar: Matrices with lexicographically-ordered rows

Bahen Centre 40 St George St, Toronto, Ontario, Canada

Speaker: Gustavo Angulo, Pontificia Universidad Católica de Chile Date/Time: August 20, 2019, 12:00pm-1:00pm Location: Bahen Centre, Room 1240 Abstract: The lexicographic order can be used to force a collection of decision vectors to be all different, i.e., to take on different values in some coordinates. We consider the set of fixed-size matrices with bounded integer […]

OR Seminar: Decomposing Optimization Problems Under Stochastic Disruptions

Bahen Centre 40 St George St, Toronto, Ontario, Canada

Speaker: Haoxiang Yang, Center for Nonlinear Studies, Los Alamos National Laboratory Date/Time: August 13, 2019, 12:00pm-1:00pm Location: Bahen Centre, Room 1220 Abstract: A stochastic disruption is a type of infrequent event in which the timing and the magnitude are random. We introduce the concept of stochastic disruptions and a stochastic optimization framework is proposed for […]