Browsing by Subject "Joint replenishment"

Now showing 1 - 4 of 4

Open Access
Design and analysis of mechanisms for decentralized joint replenishment
(Elsevier B.V., 2017) Güler, K.; Körpeoğlu, E.; Şen, A.
We consider jointly replenishing multiple firms that operate under an EOQ like environment in a decentralized, non-cooperative setting. Each firm's demand rate and inventory holding cost rate are private information. We are interested in finding a mechanism that would determine the joint replenishment frequency and allocate the joint ordering costs to these firms based on their reported stand-alone replenishment frequencies (if they were to order independently). We first provide an impossibility result showing that there is no direct mechanism that simultaneously achieves efficiency, incentive compatibility, individual rationality and budget-balance. We then propose a general, two-parameter mechanism in which one parameter is used to determine the joint replenishment frequency, another is used to allocate the order costs based on firms’ reports. We show that efficiency cannot be achieved in this two-parameter mechanism unless the parameter governing the cost allocation is zero. When the two parameters are same (a single parameter mechanism), we find the equilibrium share levels and corresponding total cost. We finally investigate the effect of this parameter on equilibrium behavior. We show that properly adjusting this parameter leads to mechanisms that are better than other mechanisms suggested earlier in the literature in terms of fairness and efficiency. © 2016 Elsevier B.V.
Open Access
Non-cooperative joint replenishment under asymmetric information
(Elsevier, 2013) Körpeoğlu, E.; Şen, A.; Güler, K.
We consider jointly replenishing n ex-ante identical firms that operate under an EOQ like setting using a non-cooperative game under asymmetric information. In this game, each firm, upon being privately informed about its demand rate (or inventory cost rate), submits a private contribution to an intermediary that specifies how much it is willing to pay for its replenishment per unit of time and the intermediary determines the maximum feasible frequency for the joint orders that would finance the fixed replenishment cost. We show that a Bayesian Nash equilibrium exists and characterize the equilibrium in this game. We also show that the contributions are monotone increasing in each firm's type. We finally conduct a numerical study to compare the equilibrium to solutions obtained under independent and cooperative ordering, and under full information. The results show that while information asymmetry eliminates free-riding in the contributions game, the resulting aggregate contributions are not as high as under full information, leading to higher aggregate costs.
Open Access
On a multiple item replenishment problem in the presence of carbon emissions
(2022-09) Şenyuva, Ilgın Efe
Motivated by the increasing popularity of sustainability issues, and the opportunities to create positive value through collaboration, the purpose of the study is to investigate a joint replenishment model in the presence of carbon emissions. The joint replenishment problem here is one where there is a deterministic demand rate over an infinite time horizon where there are major fixed, minor fixed, holding, and per unit costs and emissions. Since extensive research has been done on carbon caps and carbon tax, in order to differentiate the thesis from the existing work, a novel objective function is implemented. Through this, the optimality of the objective function has been investigated and the obtained results prove the concavity of the objective function for the common order interval and joint concavity for the item-specific order intervals. Relationships between the parameters of the variables are obtained to decrease the computational complexity. Lastly, basic numerical analysis is conducted to compare the performance of the objective function to traditional objective functions.
Open Access
A private contributions game for joint replenishment
(2012) Körpeoǧlu, E.; Şen, A.; Güler, K.
We study a non-cooperative game for joint replenishment by n firms that operate under an EOQ-like setting. Each firm decides whether to replenish independently or to participate in joint replenishment, and how much to contribute to joint ordering costs in case of participation. Joint replenishment cycle time is set by an intermediary as the lowest cycle time that can be financed with the private contributions of participating firms. We characterize the behavior and outcomes under undominated Nash equilibria.