Hessam Bavafa, E. L. Örmeci, Sergei V. Savin, Vanitha Virudachalam
How to Assess the Benefits of Coordination in Managing Hospital Resources In providing patient care, hospitals rely on multiple types of resources, such as operating rooms, recovery beds, labs, and diagnostic equipment, that are often controlled and managed as separate entities and by different decision makers. In “Surgical Case-Mix and Discharge Decisions: Does Within-Hospital Coordination Matter?” Hessam Bavafa, Lerzan Örmeci, Sergei Savin, and Vanitha Virudachalam focus on the interaction between “front-end’’ resources, such as operating rooms, and “backroom’’ resources, such as recovery beds, and compare hospital profitability under the fully coordinated, optimal approach to hospital resource management and under alternative decentralized approaches often encountered in practice. The paper identifies settings in which the benefits of coordination are likely to be high as well as settings in which those benefits are at best moderate. In a given hospital, only hospital managers are in a position to estimate with any degree of certainty potential costs of coordinated management of hospital resources, and the paper’s analysis of the benefits of coordination empowers hospital managers to make informed decisions on the desirability of replacing the often decentralized “status quo” by centralized resource management.
{"title":"Surgical Case-Mix and Discharge Decisions: Does Within-Hospital Coordination Matter?","authors":"Hessam Bavafa, E. L. Örmeci, Sergei V. Savin, Vanitha Virudachalam","doi":"10.1287/opre.2021.2177","DOIUrl":"https://doi.org/10.1287/opre.2021.2177","url":null,"abstract":"How to Assess the Benefits of Coordination in Managing Hospital Resources In providing patient care, hospitals rely on multiple types of resources, such as operating rooms, recovery beds, labs, and diagnostic equipment, that are often controlled and managed as separate entities and by different decision makers. In “Surgical Case-Mix and Discharge Decisions: Does Within-Hospital Coordination Matter?” Hessam Bavafa, Lerzan Örmeci, Sergei Savin, and Vanitha Virudachalam focus on the interaction between “front-end’’ resources, such as operating rooms, and “backroom’’ resources, such as recovery beds, and compare hospital profitability under the fully coordinated, optimal approach to hospital resource management and under alternative decentralized approaches often encountered in practice. The paper identifies settings in which the benefits of coordination are likely to be high as well as settings in which those benefits are at best moderate. In a given hospital, only hospital managers are in a position to estimate with any degree of certainty potential costs of coordinated management of hospital resources, and the paper’s analysis of the benefits of coordination empowers hospital managers to make informed decisions on the desirability of replacing the often decentralized “status quo” by centralized resource management.","PeriodicalId":19546,"journal":{"name":"Oper. Res.","volume":"7 1","pages":"990-1007"},"PeriodicalIF":0.0,"publicationDate":"2021-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81851829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In “Who Is Next: Patient Prioritization Under Emergency Department Blocking,” Li, Sun, and Hong study how physicians and nurses choose the next patient for treatment in hospital emergency departments (EDs). Using data from a tertiary hospital in Alberta, Canada, they conduct an empirical investigation and find that both clinical factors and resource constraints are considered in patient-prioritization decisions. In particular, discharged patients are prioritized when ED beds are increasingly occupied by boarding patients so as to avoid further blocking the ED. A stylized model is developed to explain the rationale behind the prioritization behavior. Using a simulation study, they show such behavior can improve ED operations by reducing the average patient waiting time and length of stay without adding extra capacity, which results in significant cost savings for hospitals.
{"title":"Who Is Next: Patient Prioritization Under Emergency Department Blocking","authors":"Wenhao Li, Zhankun Sun, L. Hong","doi":"10.2139/ssrn.3590979","DOIUrl":"https://doi.org/10.2139/ssrn.3590979","url":null,"abstract":"In “Who Is Next: Patient Prioritization Under Emergency Department Blocking,” Li, Sun, and Hong study how physicians and nurses choose the next patient for treatment in hospital emergency departments (EDs). Using data from a tertiary hospital in Alberta, Canada, they conduct an empirical investigation and find that both clinical factors and resource constraints are considered in patient-prioritization decisions. In particular, discharged patients are prioritized when ED beds are increasingly occupied by boarding patients so as to avoid further blocking the ED. A stylized model is developed to explain the rationale behind the prioritization behavior. Using a simulation study, they show such behavior can improve ED operations by reducing the average patient waiting time and length of stay without adding extra capacity, which results in significant cost savings for hospitals.","PeriodicalId":19546,"journal":{"name":"Oper. Res.","volume":"46 1","pages":"821-842"},"PeriodicalIF":0.0,"publicationDate":"2021-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75032851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Assortment optimization involves selecting a subset of products to offer to customers in order to maximize revenue. Often, the selected subset must also satisfy some constraints, such as capacity or space usage. Two key aspects in assortment optimization are (1) modeling customer behavior and (2) computing optimal or near-optimal assortments efficiently. The paired combinatorial logit (PCL) model is a generic customer choice model that allows for arbitrary correlations in the utilities of different products. The PCL model has greater modeling power than other choice models, such as multinomial-logit and nested-logit. In “Constrained Assortment Optimization Under the Paired Combinatorial Logit Model,” Ghuge, Kwon, Nagarajan, and and Sharma provide efficient algorithms that find provably near-optimal solutions for PCL assortment optimization under several types of constraints. These include the basic unconstrained problem (which is already intractable to solve exactly), multidimensional space constraints, and partition constraints. The authors also demonstrate via extensive experiments that their algorithms typically achieve over 95% of the optimal revenues.
{"title":"Constrained Assortment Optimization Under the Paired Combinatorial Logit Model","authors":"R. Ghuge, J. Kwon, V. Nagarajan, Adetee Sharma","doi":"10.1287/opre.2021.2188","DOIUrl":"https://doi.org/10.1287/opre.2021.2188","url":null,"abstract":"Assortment optimization involves selecting a subset of products to offer to customers in order to maximize revenue. Often, the selected subset must also satisfy some constraints, such as capacity or space usage. Two key aspects in assortment optimization are (1) modeling customer behavior and (2) computing optimal or near-optimal assortments efficiently. The paired combinatorial logit (PCL) model is a generic customer choice model that allows for arbitrary correlations in the utilities of different products. The PCL model has greater modeling power than other choice models, such as multinomial-logit and nested-logit. In “Constrained Assortment Optimization Under the Paired Combinatorial Logit Model,” Ghuge, Kwon, Nagarajan, and and Sharma provide efficient algorithms that find provably near-optimal solutions for PCL assortment optimization under several types of constraints. These include the basic unconstrained problem (which is already intractable to solve exactly), multidimensional space constraints, and partition constraints. The authors also demonstrate via extensive experiments that their algorithms typically achieve over 95% of the optimal revenues.","PeriodicalId":19546,"journal":{"name":"Oper. Res.","volume":"63 1","pages":"786-804"},"PeriodicalIF":0.0,"publicationDate":"2021-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84047899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Using Data to Allocate Resources Efficiently In city logistics systems, a fleet of vehicles is divided between service regions that function autonomously. Each region finds optimal routes for its own fleet and incurs costs accordingly. More vehicles lead to lower costs, but the trade-off is that fewer vehicles are left for other regions. Costs are difficult to quantify precisely because of demand uncertainty but can be estimated using data. The paper “Data-driven robust resource allocation with monotonic cost functions” by Chen, Marković, Ryzhov, and Schonfeld develops a principled risk-averse approach for two-stage resource allocation. The authors propose a new uncertainty model for decreasing cost functions and show how it can be leveraged to efficiently find resource allocations that demonstrably reduce the frequency of high-cost scenarios. This framework combines statistics and optimization in a novel way and is applicable to a general class of resource allocation problems, encompassing facility location, vehicle routing, and discrete-event simulation.
{"title":"Data-Driven Robust Resource Allocation with Monotonic Cost Functions","authors":"Ye Chen, Nikola Marković, I. Ryzhov, P. Schonfeld","doi":"10.1287/opre.2021.2145","DOIUrl":"https://doi.org/10.1287/opre.2021.2145","url":null,"abstract":"Using Data to Allocate Resources Efficiently In city logistics systems, a fleet of vehicles is divided between service regions that function autonomously. Each region finds optimal routes for its own fleet and incurs costs accordingly. More vehicles lead to lower costs, but the trade-off is that fewer vehicles are left for other regions. Costs are difficult to quantify precisely because of demand uncertainty but can be estimated using data. The paper “Data-driven robust resource allocation with monotonic cost functions” by Chen, Marković, Ryzhov, and Schonfeld develops a principled risk-averse approach for two-stage resource allocation. The authors propose a new uncertainty model for decreasing cost functions and show how it can be leveraged to efficiently find resource allocations that demonstrably reduce the frequency of high-cost scenarios. This framework combines statistics and optimization in a novel way and is applicable to a general class of resource allocation problems, encompassing facility location, vehicle routing, and discrete-event simulation.","PeriodicalId":19546,"journal":{"name":"Oper. Res.","volume":"19 1","pages":"73-94"},"PeriodicalIF":0.0,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88598811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Alberto Vera, Siddhartha Banerjee, S. Samaranayake
Motivated by the needs of modern transportation service platforms, we study the problem of computing constrained shortest paths (CSP) at scale via preprocessing techniques. Our work makes two contributions in this regard: 1) We propose a scalable algorithm for CSP queries and show how its performance can be parametrized in terms of a new network primitive, the constrained highway dimension. This development extends recent work that established the highway dimension as the appropriate primitive for characterizing the performance of unconstrained shortest-path (SP) algorithms. Our main theoretical contribution is deriving conditions relating the two notions, thereby providing a characterization of networks where CSP and SP queries are of comparable hardness. 2) We develop practical algorithms for scalable CSP computation, augmenting our theory with additional network clustering heuristics. We evaluate these algorithms on real-world data sets to validate our theoretical findings. Our techniques are orders of magnitude faster than existing approaches while requiring only limited additional storage and preprocessing.
{"title":"Computing Constrained Shortest-Paths at Scale","authors":"Alberto Vera, Siddhartha Banerjee, S. Samaranayake","doi":"10.1287/opre.2021.2166","DOIUrl":"https://doi.org/10.1287/opre.2021.2166","url":null,"abstract":"Motivated by the needs of modern transportation service platforms, we study the problem of computing constrained shortest paths (CSP) at scale via preprocessing techniques. Our work makes two contributions in this regard: 1) We propose a scalable algorithm for CSP queries and show how its performance can be parametrized in terms of a new network primitive, the constrained highway dimension. This development extends recent work that established the highway dimension as the appropriate primitive for characterizing the performance of unconstrained shortest-path (SP) algorithms. Our main theoretical contribution is deriving conditions relating the two notions, thereby providing a characterization of networks where CSP and SP queries are of comparable hardness. 2) We develop practical algorithms for scalable CSP computation, augmenting our theory with additional network clustering heuristics. We evaluate these algorithms on real-world data sets to validate our theoretical findings. Our techniques are orders of magnitude faster than existing approaches while requiring only limited additional storage and preprocessing.","PeriodicalId":19546,"journal":{"name":"Oper. Res.","volume":"16 11 1","pages":"160-178"},"PeriodicalIF":0.0,"publicationDate":"2021-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91066583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Analyzing Capacitated Two-Echelon Systems with Permutation-Dependent Separability Capacitated multiechelon systems are common in practice due to the escalating costs of labor and advanced manufacturing technology. However, identifying the optimal replenishment policies for such systems is a largely open area of research due to the intrinsic complexity, especially when there is an upstream bottleneck. In “A Permutation-Dependent Separability Approach for Capacitated Two-Echelon Inventory Systems”, Shen, Yu, and Huh propose a new approach, that is, permutation-dependent separability, to tackle a capacitated two-echelon system in which the capacity of upstream stage can be the bottleneck. They show that the value function for the capacitated two-echelon system in each period is permutation-dependent separable, and that for each echelon, a permutation-dependent echelon base stock policy is optimal. The authors also develop efficient solution procedures on how to obtain the optimal policy.
由于人工成本的不断上升和先进制造技术的不断发展,可容多级系统在实际应用中越来越普遍。然而,由于固有的复杂性,特别是当存在上游瓶颈时,确定这种系统的最佳补充政策在很大程度上是一个开放的研究领域。Shen, Yu, and Huh在“A置换依赖可分性方法for Capacitated Two-Echelon Inventory system”中,针对上游阶段的产能可能成为瓶颈的有能力两梯队系统,提出了一种新的方法,即置换依赖可分性。结果表明,有能力的两梯队系统在每个时期的价值函数是置换依赖的可分离的,并且对于每个梯队,置换依赖的梯队基存量策略是最优的。作者还开发了如何获得最优策略的有效求解程序。
{"title":"Technical Note - A Permutation-Dependent Separability Approach for Capacitated Two-Echelon Inventory Systems","authors":"Xiaobei Shen, Yimin Yu, W. T. Huh","doi":"10.1287/opre.2021.2194","DOIUrl":"https://doi.org/10.1287/opre.2021.2194","url":null,"abstract":"Analyzing Capacitated Two-Echelon Systems with Permutation-Dependent Separability Capacitated multiechelon systems are common in practice due to the escalating costs of labor and advanced manufacturing technology. However, identifying the optimal replenishment policies for such systems is a largely open area of research due to the intrinsic complexity, especially when there is an upstream bottleneck. In “A Permutation-Dependent Separability Approach for Capacitated Two-Echelon Inventory Systems”, Shen, Yu, and Huh propose a new approach, that is, permutation-dependent separability, to tackle a capacitated two-echelon system in which the capacity of upstream stage can be the bottleneck. They show that the value function for the capacitated two-echelon system in each period is permutation-dependent separable, and that for each echelon, a permutation-dependent echelon base stock policy is optimal. The authors also develop efficient solution procedures on how to obtain the optimal policy.","PeriodicalId":19546,"journal":{"name":"Oper. Res.","volume":"56 1","pages":"1953-1968"},"PeriodicalIF":0.0,"publicationDate":"2021-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83955739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Many of us will have seen uniformed guards patrolling in museums, airports, and other places where thefts or attacks are possible. In other similar places, we may have been unaware of undercover agents carrying out similar patrols. The latter type of patrollers has been modeled in recent literature. However, when the patroller is visible (wears a uniform), the potential thief or terrorist may be able to spot him when he is nearby and to time his theft appropriately. For example, the thief may wait a specified time after the uniformed patroller leaves his area. In “The Uniformed Patroller Game,” Steve Alpern, Paul Chleboun, Stamatios Katsikas, and Kyle Y. Lin study the effect on the patrolling game of having a visible (uniformed) patroller. It turns out that putting a uniform on the patroller greatly reduces his effectiveness in intercepting thefts or attacks. Of course, the visibility of a uniform may act as a deterrent to having the theft take place at all.
我们中的许多人会看到穿制服的警卫在博物馆、机场和其他可能发生盗窃或袭击的地方巡逻。在其他类似的地方,我们可能不知道卧底特工也在进行类似的巡逻。后一种类型的巡逻员已在最近的文献中建模。然而,当巡警出现时(穿着制服),当他在附近时,潜在的小偷或恐怖分子可能会发现他,并适当地选择盗窃时间。例如,小偷可能在穿制服的巡警离开他的区域后等待一段指定的时间。在“穿制服的巡逻游戏”中,Steve Alpern, Paul Chleboun, Stamatios Katsikas和Kyle Y. Lin研究了有一个可见的(穿制服的)巡逻对巡逻游戏的影响。事实证明,给巡警穿上制服大大降低了他拦截盗窃或袭击的效率。当然,制服的可见性可能会起到阻止盗窃发生的作用。
{"title":"Adversarial Patrolling in a Uniform","authors":"S. Alpern, P. Chleboun, S. Katsikas, Kyle Y. Lin","doi":"10.1287/opre.2021.2152","DOIUrl":"https://doi.org/10.1287/opre.2021.2152","url":null,"abstract":"Many of us will have seen uniformed guards patrolling in museums, airports, and other places where thefts or attacks are possible. In other similar places, we may have been unaware of undercover agents carrying out similar patrols. The latter type of patrollers has been modeled in recent literature. However, when the patroller is visible (wears a uniform), the potential thief or terrorist may be able to spot him when he is nearby and to time his theft appropriately. For example, the thief may wait a specified time after the uniformed patroller leaves his area. In “The Uniformed Patroller Game,” Steve Alpern, Paul Chleboun, Stamatios Katsikas, and Kyle Y. Lin study the effect on the patrolling game of having a visible (uniformed) patroller. It turns out that putting a uniform on the patroller greatly reduces his effectiveness in intercepting thefts or attacks. Of course, the visibility of a uniform may act as a deterrent to having the theft take place at all.","PeriodicalId":19546,"journal":{"name":"Oper. Res.","volume":"36 1","pages":"129-140"},"PeriodicalIF":0.0,"publicationDate":"2021-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81916406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Improving Newborn Screening for Genetic Diseases Screening newborns for life-threatening genetic diseases is an important public health initiative. Cystic fibrosis is one of the most prevalent diseases in this context. As part of the cystic fibrosis screening process, all states in the United States use multiple tests, including genetic tests that detect a subset of the more than 300 genetic variants (specific mutations) that cause cystic fibrosis. In “Optimal Genetic Screening for Cystic Fibrosis,” El-Hajj, D.R. Bish, and E.K. Bish develop a decision support model to select which genetic variants to screen for, considering the trade-off between classification accuracy and testing cost, and the technological constraints that limit the number of variants selected. Because variant prevalence rates are highly uncertain, a robust optimization framework is developed. Further, two commonly used cystic fibrosis screening processes are analytically compared, and conditions under which each process dominates are established. A case study based on published data are provided.
{"title":"Optimal Genetic Screening for Cystic Fibrosis","authors":"Hussein El Hajj, D. R. Bish, E. Bish","doi":"10.1287/opre.2021.2134","DOIUrl":"https://doi.org/10.1287/opre.2021.2134","url":null,"abstract":"Improving Newborn Screening for Genetic Diseases Screening newborns for life-threatening genetic diseases is an important public health initiative. Cystic fibrosis is one of the most prevalent diseases in this context. As part of the cystic fibrosis screening process, all states in the United States use multiple tests, including genetic tests that detect a subset of the more than 300 genetic variants (specific mutations) that cause cystic fibrosis. In “Optimal Genetic Screening for Cystic Fibrosis,” El-Hajj, D.R. Bish, and E.K. Bish develop a decision support model to select which genetic variants to screen for, considering the trade-off between classification accuracy and testing cost, and the technological constraints that limit the number of variants selected. Because variant prevalence rates are highly uncertain, a robust optimization framework is developed. Further, two commonly used cystic fibrosis screening processes are analytically compared, and conditions under which each process dominates are established. A case study based on published data are provided.","PeriodicalId":19546,"journal":{"name":"Oper. Res.","volume":"1 1","pages":"265-287"},"PeriodicalIF":0.0,"publicationDate":"2021-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89835452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Policymakers often seek to integrate markets as a way to maximize social welfare. In this article, the authors consider the spectrum of all possible integration policies, from full isolation to complete integration, and characterize the socially optimal market integration, under general demands. They identify market conditions under which social surplus is indeed maximized at partial market integration. For the linear price-responsive demand model that is used extensively in the operations management literature, these conditions are identified as thresholds on (i) the relative size of the markets being integrated, and (ii) the relative price sensitivity of consumers in these markets. The authors then apply the model to the commercial seed market in the European Union (EU). Their analysis shows that socially optimal market integration for these countries provides a further improvement in the social surplus for the EU by 2.80%, relative to complete integration. Results show that policymakers should exercise caution in determining the extent to which markets are integrated.
{"title":"Optimal Market-Integration Decisions by Policymakers: Modeling and Analysis of Agriculture Market Data","authors":"Shivam Gupta, S. Bansal","doi":"10.1287/opre.2021.2191","DOIUrl":"https://doi.org/10.1287/opre.2021.2191","url":null,"abstract":"Policymakers often seek to integrate markets as a way to maximize social welfare. In this article, the authors consider the spectrum of all possible integration policies, from full isolation to complete integration, and characterize the socially optimal market integration, under general demands. They identify market conditions under which social surplus is indeed maximized at partial market integration. For the linear price-responsive demand model that is used extensively in the operations management literature, these conditions are identified as thresholds on (i) the relative size of the markets being integrated, and (ii) the relative price sensitivity of consumers in these markets. The authors then apply the model to the commercial seed market in the European Union (EU). Their analysis shows that socially optimal market integration for these countries provides a further improvement in the social surplus for the EU by 2.80%, relative to complete integration. Results show that policymakers should exercise caution in determining the extent to which markets are integrated.","PeriodicalId":19546,"journal":{"name":"Oper. Res.","volume":"16 1","pages":"352-362"},"PeriodicalIF":0.0,"publicationDate":"2021-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91283686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The paper “Fluid-Diffusion-Hybrid (FDH) Approximation” proposes a new heavy-traffic asymptotic regime for a two-class priority system in which the high-priority customers require substantially larger service times than the low-priority customers. In the FDH limit, the high-priority queue is a diffusion, whereas the low-priority queue operates as a (random) fluid limit, whose dynamics are driven by the former diffusion. A characterizing property of our limit process is that, unlike other asymptotic regimes, a non-negligible proportion of the customers from both classes must wait for service. This property allows us to study the costs and benefits of de-pooling, and prove that a two-pool system is often the asymptotically optimal design of the system.
{"title":"A Fluid-Diffusion-Hybrid Limiting Approximation for Priority Systems with Fast and Slow Customers","authors":"Lun Yu, S. Iravani, Ohad Perry","doi":"10.1287/opre.2021.2154","DOIUrl":"https://doi.org/10.1287/opre.2021.2154","url":null,"abstract":"The paper “Fluid-Diffusion-Hybrid (FDH) Approximation” proposes a new heavy-traffic asymptotic regime for a two-class priority system in which the high-priority customers require substantially larger service times than the low-priority customers. In the FDH limit, the high-priority queue is a diffusion, whereas the low-priority queue operates as a (random) fluid limit, whose dynamics are driven by the former diffusion. A characterizing property of our limit process is that, unlike other asymptotic regimes, a non-negligible proportion of the customers from both classes must wait for service. This property allows us to study the costs and benefits of de-pooling, and prove that a two-pool system is often the asymptotically optimal design of the system.","PeriodicalId":19546,"journal":{"name":"Oper. Res.","volume":"2 1","pages":"2579-2596"},"PeriodicalIF":0.0,"publicationDate":"2021-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90550899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}