Pub Date : 2024-11-07DOI: 10.1016/j.ejor.2024.10.043
Pengyu Wei, Zuo Quan Xu
This paper studies a mean-risk portfolio choice problem for log-returns in a continuous-time, complete market. It is a growth-optimal portfolio choice problem under risk control. The risk of log-returns is measured by weighted Value-at-Risk (WVaR), which is a generalization of Value-at-Risk (VaR) and Expected Shortfall (ES). We characterize the optimal terminal wealth and obtain analytical expressions when risk is measured by VaR or ES. We demonstrate that using VaR increases losses while ES reduces losses during market downturns. Moreover, the efficient frontier is a concave curve that connects the minimum-risk portfolio with the growth optimal portfolio, as opposed to the vertical line when WVaR is used on terminal wealth, and thus allows for a meaningful characterization of the risk-return trade-off and aids investors in setting reasonable investment targets. We also apply our model to benchmarking and illustrate how investors with benchmarking may overperform/underperform the market depending on economic conditions.
本文研究的是连续时间完全市场中对数收益的均值风险投资组合选择问题。这是一个风险控制下的增长最优投资组合选择问题。对数收益率的风险用加权风险价值（WVaR）来衡量，它是风险价值（VaR）和预期缺口（ES）的广义化。当风险以 VaR 或 ES 度量时，我们将描述最优终端财富的特征并获得分析表达式。我们证明，在市场低迷时，使用 VaR 会增加损失，而 ES 则会减少损失。此外，有效前沿是一条连接最小风险投资组合和最优增长投资组合的凹曲线，而不是使用风险价值增值率衡量终端财富时的垂直线，因此可以对风险收益权衡进行有意义的描述，并帮助投资者设定合理的投资目标。我们还将模型应用于基准投资，并说明了具有基准投资能力的投资者如何根据经济状况跑赢/跑输市场。
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Pub Date : 2024-11-07DOI: 10.1016/j.ejor.2024.10.040
Benedikt Zipfel, Felix Tamke, Leopold Kuttner
In recent years, there has been considerable interest in the transformative potential of additive manufacturing (AM) since it allows for producing highly customizable and complex components while reducing lead times and costs. The rise of AM for traditional and new business models enforces the need for efficient planning procedures for AM facilities. In this area, the assignment and sequencing of components to be built by an AM machine, also called a 3D printer, is a complex challenge combining two combinatorial problems: The first decision involves the grouping of parts into production batches, akin to the well-known bin packing problem. Subsequently, the second problem pertains to the scheduling of these batches onto the available machines, which corresponds to a parallel machine scheduling problem. For minimizing makespan, this paper proposes a new branch-and-cut algorithm for integrated planning for unrelated parallel machines. The algorithm is based on combinatorial Benders decomposition: The scheduling problem is considered in the master problem, while the feasibility of an obtained solution with respect to the packing problem is checked in the sub-problem. Current state-of-the-art techniques are extended to solve the orthogonal packing with rotation and used to speed up the solution of the sub-problem. Extensive computational tests on existing and new benchmark instances show the algorithm’s superior performance, improving the makespan by 18.7% on average, with improvements reaching up to 97.6% for large problems compared to an existing integrated mixed-integer programming model.
近年来，人们对增材制造（AM）的变革潜力产生了浓厚的兴趣，因为它可以生产高度定制化的复杂部件，同时缩短交付周期并降低成本。随着传统和新型商业模式中增材制造的兴起，对增材制造设备的高效规划程序提出了更高的要求。在这一领域，AM 机器（也称为 3D 打印机）要制造的部件的分配和排序是一个复杂的挑战，它结合了两个组合问题：第一个决定涉及将部件分组到生产批次中，类似于著名的料仓包装问题。随后，第二个问题涉及将这些批次安排到可用机器上，这相当于并行机器调度问题。为了最小化生产间隔，本文提出了一种新的分支-切割算法，用于对不相关的并行机器进行综合规划。该算法基于组合 Benders 分解：在主问题中考虑调度问题，而在子问题中检查获得的解决方案对于打包问题的可行性。当前最先进的技术被扩展用于解决旋转正交打包问题，并用于加快子问题的解决速度。在现有的和新的基准实例上进行的大量计算测试表明，与现有的综合混合整数编程模型相比，该算法性能优越，平均可将时间跨度提高 18.7%，在大型问题上的改进幅度最高可达 97.6%。
{"title":"A new branch-and-cut approach for integrated planning in additive manufacturing","authors":"Benedikt Zipfel, Felix Tamke, Leopold Kuttner","doi":"10.1016/j.ejor.2024.10.040","DOIUrl":"https://doi.org/10.1016/j.ejor.2024.10.040","url":null,"abstract":"In recent years, there has been considerable interest in the transformative potential of additive manufacturing (AM) since it allows for producing highly customizable and complex components while reducing lead times and costs. The rise of AM for traditional and new business models enforces the need for efficient planning procedures for AM facilities. In this area, the assignment and sequencing of components to be built by an AM machine, also called a 3D printer, is a complex challenge combining two combinatorial problems: The first decision involves the grouping of parts into production batches, akin to the well-known bin packing problem. Subsequently, the second problem pertains to the scheduling of these batches onto the available machines, which corresponds to a parallel machine scheduling problem. For minimizing makespan, this paper proposes a new branch-and-cut algorithm for integrated planning for unrelated parallel machines. The algorithm is based on combinatorial Benders decomposition: The scheduling problem is considered in the master problem, while the feasibility of an obtained solution with respect to the packing problem is checked in the sub-problem. Current state-of-the-art techniques are extended to solve the orthogonal packing with rotation and used to speed up the solution of the sub-problem. Extensive computational tests on existing and new benchmark instances show the algorithm’s superior performance, improving the makespan by 18.7% on average, with improvements reaching up to 97.6% for large problems compared to an existing integrated mixed-integer programming model.","PeriodicalId":55161,"journal":{"name":"European Journal of Operational Research","volume":"143 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142670501","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"管理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-06DOI: 10.1016/j.ejor.2024.10.029
T. van der Beek, J.T. van Essen, J. Pruyn, K. Aardal
The Resource Constrained Project Scheduling Problem with a flexible Project Structure (RCPSP-PS) is a generalization of the Resource Constrained Project Scheduling Problem (RCPSP). In the RCPSP, the goal is to determine a minimal makespan schedule subject to precedence and resource constraints. The generalization introduced in the RCPSP-PS is that, instead of executing all activities, only a subset of all activities has to be executed. We present a model that is based on two graphs: one representing precedence relations and one representing the activity selection structure. The latter defines which subset of activities has to be executed. Additionally, we present theoretical properties of this model and give an exact solution method that makes use of these properties by generating cutting planes and setting bounds on variables. Furthermore, three problem properties are introduced to classify problems in the literature. We compare our model to a model from literature on instances that possess a subset of these three problem properties and find a reduction in computing time. Furthermore, by comparing results on instances that possess all problem properties, it is shown that the computing times are decreased and better lower bounds are found by the cutting planes and variable bounds presented in this paper.
{"title":"Exact solution methods for the Resource Constrained Project Scheduling Problem with a flexible Project Structure","authors":"T. van der Beek, J.T. van Essen, J. Pruyn, K. Aardal","doi":"10.1016/j.ejor.2024.10.029","DOIUrl":"https://doi.org/10.1016/j.ejor.2024.10.029","url":null,"abstract":"The Resource Constrained Project Scheduling Problem with a flexible Project Structure (RCPSP-PS) is a generalization of the Resource Constrained Project Scheduling Problem (RCPSP). In the RCPSP, the goal is to determine a minimal makespan schedule subject to precedence and resource constraints. The generalization introduced in the RCPSP-PS is that, instead of executing all activities, only a subset of all activities has to be executed. We present a model that is based on two graphs: one representing precedence relations and one representing the activity selection structure. The latter defines which subset of activities has to be executed. Additionally, we present theoretical properties of this model and give an exact solution method that makes use of these properties by generating cutting planes and setting bounds on variables. Furthermore, three problem properties are introduced to classify problems in the literature. We compare our model to a model from literature on instances that possess a subset of these three problem properties and find a reduction in computing time. Furthermore, by comparing results on instances that possess all problem properties, it is shown that the computing times are decreased and better lower bounds are found by the cutting planes and variable bounds presented in this paper.","PeriodicalId":55161,"journal":{"name":"European Journal of Operational Research","volume":"7 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142670548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"管理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-06DOI: 10.1016/j.ejor.2024.10.047
Cigdem Karademir, Breno A. Beirigo, Bilge Atasoy
This study focuses on two-echelon synchronized logistics problems in the context of integrated water- and land-based transportation (IWLT) systems. The aim is to meet the increasing demand in city logistics as a result of the growth in transport activities, including parcel delivery, food delivery, and waste collection. We propose two models, a novel mixed integer linear joint model, and a logic-based Benders’ decomposition (LBBD) model, for a two-echelon problem under realistic settings such as multi-trips, time windows, and synchronization at the satellites with no storage and limited resource capacities. The objective is to optimize transfers and satellite assignments, thereby reducing overall logistics costs for street vehicles and vessels. Computational experiments demonstrate that the LBBD model is more robust in terms of solution quality and solution time on average while the added value of the LBBD is more evident when solving large-scale instances with 100 customers, reducing the overall costs by 10.6% on average and significantly reducing the fleet costs on both networks. Furthermore, we assess the effect of changing cost parameters and satellite locations in the proposed IWLT system–analyzing system behavior and suggesting potential improvements–and evaluate several system alternatives in city logistics–consisting of different transportation network designs (single- and two-echelon), vehicle types, and operational constraints. On average, the proposed two-echelon IWLT system reduces the number of kilometers traveled by vehicles at street level by ranging from 20% to 30% compared to a typical single-echelon service design that relies solely on trucks.
{"title":"A two-echelon multi-trip vehicle routing problem with synchronization for an integrated water- and land-based transportation system","authors":"Cigdem Karademir, Breno A. Beirigo, Bilge Atasoy","doi":"10.1016/j.ejor.2024.10.047","DOIUrl":"https://doi.org/10.1016/j.ejor.2024.10.047","url":null,"abstract":"This study focuses on two-echelon synchronized logistics problems in the context of integrated water- and land-based transportation (IWLT) systems. The aim is to meet the increasing demand in city logistics as a result of the growth in transport activities, including parcel delivery, food delivery, and waste collection. We propose two models, a novel mixed integer linear joint model, and a logic-based Benders’ decomposition (LBBD) model, for a two-echelon problem under realistic settings such as multi-trips, time windows, and synchronization at the satellites with no storage and limited resource capacities. The objective is to optimize transfers and satellite assignments, thereby reducing overall logistics costs for street vehicles and vessels. Computational experiments demonstrate that the LBBD model is more robust in terms of solution quality and solution time on average while the added value of the LBBD is more evident when solving large-scale instances with 100 customers, reducing the overall costs by 10.6% on average and significantly reducing the fleet costs on both networks. Furthermore, we assess the effect of changing cost parameters and satellite locations in the proposed IWLT system–analyzing system behavior and suggesting potential improvements–and evaluate several system alternatives in city logistics–consisting of different transportation network designs (single- and two-echelon), vehicle types, and operational constraints. On average, the proposed two-echelon IWLT system reduces the number of kilometers traveled by vehicles at street level by ranging from 20% to 30% compared to a typical single-echelon service design that relies solely on trucks.","PeriodicalId":55161,"journal":{"name":"European Journal of Operational Research","volume":"35 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142670546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"管理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-06DOI: 10.1016/j.ejor.2024.10.039
J. Matias Kivikangas, Eeva Vilkkumaa, Julian Blank, Ville Harjunen, Pekka Malo, Kalyanmoy Deb, Niklas J. Ravaja, Jyrki Wallenius
Practical planning and decision-making problems are often better and more accurately formulated with multiple conflicting objectives rather than a single objective. This study investigates a situation relevant for Multiple Criteria Decision Making (MCDM) as well as Evolutionary Multi-objective Optimization (EMO), where the decision-maker needs to make a series of choices between nondominated options characterized by multiple objectives. The cognitive capacity of humans is limited, which leads to cognitive burden that influences human decision-makers’ decisions. We measure how the varying number of objectives influences cognitive burden in a laboratory study, and the impacts that this burden has on the decision-makers’ behavior and the consistency of their decisions. We use psychophysiological, behavioral, and self-report methods. Our results suggest that a higher number of objectives (i) increases cognitive burden significantly, (ii) leads to adopting strategies in which only a limited number of objectives is considered, and (iii) decreases decision consistency.
{"title":"Effects of many conflicting objectives on decision-makers’ cognitive burden and decision consistency","authors":"J. Matias Kivikangas, Eeva Vilkkumaa, Julian Blank, Ville Harjunen, Pekka Malo, Kalyanmoy Deb, Niklas J. Ravaja, Jyrki Wallenius","doi":"10.1016/j.ejor.2024.10.039","DOIUrl":"https://doi.org/10.1016/j.ejor.2024.10.039","url":null,"abstract":"Practical planning and decision-making problems are often better and more accurately formulated with multiple conflicting objectives rather than a single objective. This study investigates a situation relevant for Multiple Criteria Decision Making (MCDM) as well as Evolutionary Multi-objective Optimization (EMO), where the decision-maker needs to make a series of choices between nondominated options characterized by multiple objectives. The cognitive capacity of humans is limited, which leads to <ce:italic>cognitive burden</ce:italic> that influences human decision-makers’ decisions. We measure how the varying number of objectives influences cognitive burden in a laboratory study, and the impacts that this burden has on the decision-makers’ behavior and the consistency of their decisions. We use psychophysiological, behavioral, and self-report methods. Our results suggest that a higher number of objectives (i) increases cognitive burden significantly, (ii) leads to adopting strategies in which only a limited number of objectives is considered, and (iii) decreases decision consistency.","PeriodicalId":55161,"journal":{"name":"European Journal of Operational Research","volume":"80 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142670547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"管理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-05DOI: 10.1016/j.ejor.2024.10.041
Alan Osorio-Mora, Francisco Saldanha-da-Gama, Paolo Toth
In this paper, a latency location-routing problem with stochastic travel times is investigated. The problem is cast as a two-stage stochastic program. The ex-ante decision comprises the location of the depots. The ex-post decision regards the routing, which adapts to the observed travel times. A risk-averse decision-maker is assumed, which is conveyed by adopting the latency CVaRα as the objective function. The problem is formulated mathematically. An efficient multi-start variable neighborhood search algorithm is proposed for tackling the problem when uncertainty is captured by a finite set of scenarios. This procedure is then embedded into a sampling mechanism so that realistic instances of the problem can be tackled, namely when the travel times are represented by random vectors with an infinite support. An extensive computational analysis is conducted to assess the methodological developments proposed and the relevance of capturing uncertainty in the problem. Additional insights include the impact of the risk level in the solutions.
{"title":"A risk-averse latency location-routing problem with stochastic travel times","authors":"Alan Osorio-Mora, Francisco Saldanha-da-Gama, Paolo Toth","doi":"10.1016/j.ejor.2024.10.041","DOIUrl":"https://doi.org/10.1016/j.ejor.2024.10.041","url":null,"abstract":"In this paper, a latency location-routing problem with stochastic travel times is investigated. The problem is cast as a two-stage stochastic program. The ex-ante decision comprises the location of the depots. The ex-post decision regards the routing, which adapts to the observed travel times. A risk-averse decision-maker is assumed, which is conveyed by adopting the latency CVaR<mml:math altimg=\"si1.svg\" display=\"inline\"><mml:msub><mml:mrow></mml:mrow><mml:mrow><mml:mi>α</mml:mi></mml:mrow></mml:msub></mml:math> as the objective function. The problem is formulated mathematically. An efficient multi-start variable neighborhood search algorithm is proposed for tackling the problem when uncertainty is captured by a finite set of scenarios. This procedure is then embedded into a sampling mechanism so that realistic instances of the problem can be tackled, namely when the travel times are represented by random vectors with an infinite support. An extensive computational analysis is conducted to assess the methodological developments proposed and the relevance of capturing uncertainty in the problem. Additional insights include the impact of the risk level in the solutions.","PeriodicalId":55161,"journal":{"name":"European Journal of Operational Research","volume":"56 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142670549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"管理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-04DOI: 10.1016/j.ejor.2024.10.025
Jie Song, Jinbo Song, Mario Vanhoucke
During project execution, the actual project progress shows deviations from the baseline schedule due to uncertainty. To complete the project timely, project monitoring is performed at discrete control points to identify project opportunities/problems and take possible corrective actions. These control points affect the quality of project monitoring and corrective actions, but little guidance is available on identifying situations where the control points pay off the most in terms of project duration.
{"title":"Automatic selection of the best performing control point approach for project control with resource constraints","authors":"Jie Song, Jinbo Song, Mario Vanhoucke","doi":"10.1016/j.ejor.2024.10.025","DOIUrl":"https://doi.org/10.1016/j.ejor.2024.10.025","url":null,"abstract":"During project execution, the actual project progress shows deviations from the baseline schedule due to uncertainty. To complete the project timely, project monitoring is performed at discrete control points to identify project opportunities/problems and take possible corrective actions. These control points affect the quality of project monitoring and corrective actions, but little guidance is available on identifying situations where the control points pay off the most in terms of project duration.","PeriodicalId":55161,"journal":{"name":"European Journal of Operational Research","volume":"143 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142670493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"管理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-04DOI: 10.1016/j.ejor.2024.11.003
Luís C. Dias, Panos Xidonas, Aristeidis Samitas
A Sigma-Mu approach is proposed for mutual funds portfolio selection. The mean and variance of the overall performance of each asset are considered, according to an additive aggregation model, subject to weights’ preferences provided by the decision maker. These preferences concern two independent sets of weights, i.e., those pertaining to the investment indicators and those pertaining to the time periods associated with the estimation of the indicators. For the first time in the Sigma-Mu framework, a weighting matrix is exploited, assisting on the development of a method to appraise the sources of variance, due to the weighting scheme of either the indicators or the periods. The Mu's, Sigma's and covariances estimated according to the Sigma-Mu approach, enter as inputs to mixed-integer quadratic programming (MIQP) mean-variance portfolio optimization models, in order to implement an empirical testing procedure, for a period of 8 years. The underlying MIQP models are equipped to consider non-convex investment policy constraints, such as the number of securities to be included in the portfolio, specific binary buy-in thresholds, the desired exposure of the portfolio to each investment advisor etc. The dataset that has been chosen for the empirical testing includes European mutual funds, that offer a broad exposure to the whole span of investment strategies and styles. The results document that the suggested approach may effectively be utilized in mutual funds investment management, since the portfolios constructed by the suggested methodology are associated with superior absolute and risk-adjusted performance against benchmarks.
{"title":"A novel sigma-Mu multiple criteria decision aiding approach for mutual funds portfolio selection","authors":"Luís C. Dias, Panos Xidonas, Aristeidis Samitas","doi":"10.1016/j.ejor.2024.11.003","DOIUrl":"https://doi.org/10.1016/j.ejor.2024.11.003","url":null,"abstract":"A <ce:italic>Sigma-Mu</ce:italic> approach is proposed for mutual funds portfolio selection. The mean and variance of the overall performance of each asset are considered, according to an additive aggregation model, subject to weights’ preferences provided by the decision maker. These preferences concern two independent sets of weights, i.e., those pertaining to the <ce:italic>investment indicators</ce:italic> and those pertaining to the <ce:italic>time periods</ce:italic> associated with the estimation of the indicators. For the first time in the <ce:italic>Sigma-Mu</ce:italic> framework, a weighting matrix is exploited, assisting on the development of a method to appraise the sources of variance, due to the weighting scheme of either the indicators or the periods. The Mu's, Sigma's and covariances estimated according to the <ce:italic>Sigma-Mu</ce:italic> approach, enter as inputs to mixed-integer quadratic programming (MIQP) mean-variance portfolio optimization models, in order to implement an empirical testing procedure, for a period of 8 years. The underlying MIQP models are equipped to consider non-convex investment policy constraints, such as the number of securities to be included in the portfolio, specific binary buy-in thresholds, the desired exposure of the portfolio to each investment advisor etc. The dataset that has been chosen for the empirical testing includes European mutual funds, that offer a broad exposure to the whole span of investment strategies and styles. The results document that the suggested approach may effectively be utilized in mutual funds investment management, since the portfolios constructed by the suggested methodology are associated with superior absolute and risk-adjusted performance against benchmarks.","PeriodicalId":55161,"journal":{"name":"European Journal of Operational Research","volume":"11 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142670550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"管理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-30DOI: 10.1016/j.ejor.2024.10.021
Martijn W. Ketelaars, Peter M. Kort
This article considers a sequential investment project which starts with a product innovation phase, and subsequently, once R&D is completed, a production phase. The investment decisions are the timing and size of the R&D investment, and the size of the production capacity. We show that from a social welfare perspective the firm starts the R&D project too late and installs a too low production capacity. We find that subsidization of the R&D investment is more effective in reducing this welfare loss than subsidization of the production capacity. In fact, we reach the same conclusion under both isoelastic and linear demand.
{"title":"On subsidization of investments in R&D and production capacity","authors":"Martijn W. Ketelaars, Peter M. Kort","doi":"10.1016/j.ejor.2024.10.021","DOIUrl":"https://doi.org/10.1016/j.ejor.2024.10.021","url":null,"abstract":"This article considers a sequential investment project which starts with a product innovation phase, and subsequently, once R&D is completed, a production phase. The investment decisions are the timing and size of the R&D investment, and the size of the production capacity. We show that from a social welfare perspective the firm starts the R&D project too late and installs a too low production capacity. We find that subsidization of the R&D investment is more effective in reducing this welfare loss than subsidization of the production capacity. In fact, we reach the same conclusion under both isoelastic and linear demand.","PeriodicalId":55161,"journal":{"name":"European Journal of Operational Research","volume":"19 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142670551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"管理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-29DOI: 10.1016/S0377-2217(24)00807-5
{"title":"Prelim p. 2; First issue - Editorial Board","authors":"","doi":"10.1016/S0377-2217(24)00807-5","DOIUrl":"10.1016/S0377-2217(24)00807-5","url":null,"abstract":"","PeriodicalId":55161,"journal":{"name":"European Journal of Operational Research","volume":"321 1","pages":"Page ii"},"PeriodicalIF":6.0,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142537246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"管理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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