Appointment, Advance and Combined Scheduling

Assoc. Prof. Mehmet A. Begen

Ivey Business School, Western University, Canada

11 July 2023 Tuesday, 14:00-15:00



Appointment scheduling involves scheduling of given jobs (e.g., surgeries, physician appointments) on a highly utilized resource (e.g., operating room, physician) when the processing durations are stochastic and there are significant underage (resource idle-time) and overage (job waiting and/or resource overtime) costs. The goal is to find a schedule (appointment times or allocated durations) that would optimize an objective (e.g., expected total cost, a percentile of total cost).

Advance scheduling has uncertainty in the number of job arrivals (e.g., different type/priority of patients), future job demand is not known, and the goal is to assign jobs to future dates (e.g., which day a patient to be served) to optimize an objective, (e.g., expected total cost of waiting, delays beyond a target deadline and overtime). The decisions are how many jobs to book (of different types/priority levels) on a specific day in the booking horizon.

Both problems are highly dependent each other since the output of one of them is an input to another. However due to curse of dimensionality, incompatibility between the approaches used to model the two problems and the additional complexity associated with considering sequencing decisions in appointment scheduling forced researchers to consider these both problems independently, or at least separately and sequentially, which only achieves suboptimal results.

In this talk, we will introduce both problems, discuss some of the approaches to solve them and present recent attempts to combine them, i.e., jointly solve them. Combined approaches use the inter-dependency between the problems and strives to optimize both problems simultaneously. There are many application areas of these problems such as those in surgery, diagnostic imagining, cancer treatment, rehabilitation services and home healthcare.


Dr. Mehmet A. Begen is an associate professor of management science in the Ivey Business School at the Western University, Canada. Besides Ivey, he is also cross-appointed at the departments of Statistical & Actuarial Sciences and Epidemiology & Biostatistics at Western.

Mehmet's research interests are management science/analytics applications, data-driven approaches and in particular scheduling and operations management in healthcare. The topics include contract design, healthcare applications, production planning, supply chain management, resource allocation and decision making under uncertainty. He is industrial engineer and a Certified Analytics Professional (CAP), worked in management consulting before his PhD studies. Mehmet worked with organizations around the world to implement analytics for business challenges.

Mehmet has taught various analytics courses almost at all levels. He received teaching awards, research awards and external funding. Mehmet served as various capacities (education chair, VP, president and past president) to Canadian Operations Research Society (CORS) and served on organizing committees of INFORMS conferences.