Service systems are typically limited resource environments where scarce capacity is reserved for the most urgent customers. However, there has been a growing interest in the use of proactive service when a less urgent customer may become urgent while waiting. On one hand, providing service for customers when they are less urgent could mean that fewer resources are needed to fulfill their service requirement. On the other hand, using limited capacity for customers who may never need the service in the future takes the capacity away from other more urgent customers who need it now. To understand this tension, we propose a multiserver queueing model with two customer classes: moderate and urgent. We allow customers to transition classes while waiting. In this setting, we characterize how moderate and urgent customers should be prioritized for service when proactive service for moderate customers is an option. We identify an index, the modified [Formula: see text]-index, which plays an important role in determining the optimal scheduling policy. This index lends itself to an intuitive interpretation of how to balance holding costs, service times, abandonments, and transitions between customer classes. This paper was accepted by David Simchi-Levi, stochastic models and simulation. 
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                            Hybrid Priority Queue and its Applications
                        
                    
    
            Priority queues are well understood in queueing theory. However, they are somewhat restrictive in that the low-priority customers suffer far greater waiting times than the highpriority customers. In this short paper, we introduce a novel generalization of a two-class priority queue, which we call Hybrid. We prove that Hybrid has a much broader achievability region than strict priority, allowing for a much greater range of waiting time pairs. We demonstrate settings where this new flexibility can increase the revenue obtained by a service system (like airport TSA) selling priority. 
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                            - PAR ID:
- 10579742
- Publisher / Repository:
- Performance Evaluation Review
- Date Published:
- Journal Name:
- ACM SIGMETRICS Performance Evaluation Review
- Volume:
- 52
- Issue:
- 2
- ISSN:
- 0163-5999
- Page Range / eLocation ID:
- 12 to 14
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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