Impact of Auto-regressive (AR) Process in Bullwhip Analysis in a Multi-location Supply Chain Network

2019 ◽  
Vol 6 (1) ◽  
pp. 19-26 ◽  
Author(s):  
Prabhat Mittal

The present study is an attempt to quantify the Bullwhip Effect (BWE) -the phenomenon in which information on demand is distorted in moving up a supply chain. Assuming that the retailer employs an order-up-to level policy with auto-regressive process (AR), the paper investigates the influence of forecasting methods on bullwhip effect. Determining the order-up-to levels and the orders for the retailers’ demands in an isolated manner neglects the correlation of the demands and the relevant risk pooling effects associated with the network structure of the supply chains are disregarded. It is illustrated that the bullwhip effects are significantly reduced with consideration of potential correlation between the retailers’ demand.

2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
Yongchang Wei ◽  
Hongwei Wang ◽  
Fangyu Chen

A supply chain network might exhibit complex dynamics in the face of increasingly volatile and uncertain environment. The impact of network structure and collaboration on the dynamics and robustness of supply chain network, however, remains to be explored. In this paper, a unified state space model for a two-layer supply chain network composed of multiple distributors and multiple retailers is developed. A robust control algorithm is advocated to reduce both order and demand fluctuations for unknown demand. Numerical simulations demonstrate that the robust control approach has the advantage to reduce both inventory and order fluctuations. In the simulation experiment, it is interesting to notice that complex network structure and collaborations might contribute to the reduction of inventory and order oscillations. This paper yields new insights into the overestimated bullwhip effect problem and helps us understand the complexities of supply chain networks.


2020 ◽  
Author(s):  
Zhan Qu ◽  
Horst Raff

This paper shows that decentralized supply chains, in which upstream firms use linear wholesale prices, may experience lower upstream production and downstream sales volatility than vertically integrated supply chains and may be less susceptible to the bullwhip effect by which the variance of upstream production exceeds the variance of downstream sales. The reason is that decentralized supply chains exhibit a price effect, whereby upstream producers raise wholesale prices in the case of positive demand shocks and lower wholesale prices in the case of negative demand shocks. Whereas upstream producers benefit from the price effect and, thus, from a dampening of the bullwhip effect, downstream firms may lose, and overall supply chain profit may decrease. This paper was accepted by Vishal Gaur, operations management.


Complexity ◽  
2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Junhai Ma ◽  
Wandong Lou

This paper studies the complex characteristics caused by the price competition in multichannel household appliance supply chains. We consider a two-level household appliance supply chain system consisting of a manufacturer with an Internet channel and a retailer with a traditional channel and an Internet channel. Each channel’s price-setting follows the bounded rational decision process in order to obtain the optimal profit or more market share. Considering that the price competition often leads to the demand and order fluctuation, we also investigate the bullwhip effect of the multichannel supply chains on the basis of the order-up-to-inventory policy. From the numerical simulation, we find a system in a chaotic state will suffer larger bullwhip effect than a stable system, and the manufacturer’s Internet channel is helpful to mitigate the bullwhip effect. Our results provide some useful managerial inspirations for the household manufacturer and retailers. Firstly, each channel should make their retail price with a suitable price adjustment speed in the stable region, and each time pricing cannot exceed the domain of attraction. Secondly, the manufacturer can adopt a more radical pricing strategy in their Internet channel to mitigate the bullwhip effect. Thirdly, the price adjustment should be reviewed and be appropriately reduced if the price adjustment is too large.


2012 ◽  
pp. 646-665
Author(s):  
Mehdi Najafi ◽  
Reza Zanjirani Farahani

In today’s world, all enterprises in a supply chain are attempting to increase both their and the supply chain’s efficiency and effectiveness. Therefore, identification and consideration of factors that prevent enterprises to attain their expected/desired levels of effectiveness are very important. Since bullwhip effect is one of these main factors, being aware of its reasons help enterprises decrease the severity of bullwhip effect by opting proper decisions. Now that forecasting method is one of the most important factors in increasing or decreasing the bullwhip effect, this chapter considers and compares the effects of various forecasting methods on the bullwhip effect. In fact, in this chapter, the effects of various forecasting methods, such as Moving Average, Exponential Smoothing, and Regression, in terms of their associated bullwhip effect, in a four echelon supply chain- including retailer, wholesaler, manufacturer, and supplier- are considered. Then, the bullwhip effect measure is utilized to compare the ineffectiveness of various forecasting methods. Owing to this, the authors generate two sets of demands in the two cases where the demand is constant (no trend) and has an increasing trend, respectively. Then, the chapter ranks the forecasting methods in these two cases and utilizes a statistical method to ascertain the significance of differences among the effects of various methods.


2019 ◽  
Vol 14 (2) ◽  
pp. 360-384 ◽  
Author(s):  
Maria Drakaki ◽  
Panagiotis Tzionas

PurposeInformation distortion results in demand variance amplification in upstream supply chain members, known as the bullwhip effect, and inventory inaccuracy in the inventory records. As inventory inaccuracy contributes to the bullwhip effect, the purpose of this paper is to investigate the impact of inventory inaccuracy on the bullwhip effect in radio-frequency identification (RFID)-enabled supply chains and, in this context, to evaluate supply chain performance because of the RFID technology.Design/methodology/approachA simulation modeling method based on hierarchical timed colored petri nets is presented to model inventory management in multi-stage serial supply chains subject to inventory inaccuracy for various traditional and information sharing configurations in the presence and absence of RFID. Validation of the method is done by comparing results obtained for the bullwhip effect with published literature results.FindingsThe bullwhip effect is increased in RFID-enabled multi-stage serial supply chains subject to inventory inaccuracy. The information sharing supply chain is more sensitive to the impact of inventory inaccuracy.Research limitations/implicationsInformation sharing involves collaboration in market demand and inventory inaccuracy, whereas RFID is implemented by all echelons. To obtain the full benefits of RFID adoption and collaboration, different collaboration strategies should be investigated.Originality/valueColored petri nets simulation modeling of the inventory management process is a novel approach to study supply chain dynamics. In the context of inventory errors, information on RFID impact on the dynamic behavior of multi-stage serial supply chains is provided.


2020 ◽  
Vol 40 (10) ◽  
pp. 1649-1660 ◽  
Author(s):  
Robert B. Handfield ◽  
Gary Graham ◽  
Laird Burns

PurposeUsing the constructal law of physics this study aims to provide guidance to future scholarship on global supply chain management. Further, through two case studies the authors are developing, the authors report interview findings with two senior VPs from two multi-national corporations being disrupted by COVID-19. This study suggests how this and recent events will impact on the design of future global supply chains.Design/methodology/approachThe authors apply the constructal law to explain the recent disruptions to the global supply chain orthodoxy. Two interviews are presented from case studies the authors are developing in the USA and UK – one a multi-national automobile parts supplier and the other is a earth-moving equipment manufacture. Specifically, this is an exploratory pathway work trying to make sense of the COVID-19 pandemic and its impact on supply chain scholarship.FindingsAdopting the approach of Bejan, the authors believe that what is happening today with COVID-19 and other trade disruptions such as Brexit and the USA imposing tariffs is creating new obstacles that will redirect the future flow of supply chains.Research limitations/implicationsIt is clear that the COVID-19 response introduced a bullwhip effect in the manufacturing sector on a scale never-before seen. For scholars, the authors would suggest there are four pathway topics going forward. These topics include: the future state of global sourcing, the unique nature of a combined “demand” and “supply shortage” bullwhip effect, the resurrection of lean and local production systems and the development of risk-recovery contingency strategies to deal with pandemics.Practical implicationsSupply chain managers tend to be iterative and focused on making small and subtle changes to their current system and way of thinking, very often seeking to optimize cost or negotiate better contracts with suppliers. In the current environment, however, such activities have proved to be of little consequence compared to the massive forces of economic disruption of the past three years. Organizations that have more tightly compressed supply chains are enjoying a significant benefit during the COVID-19 crisis and are no longer being held hostage to governments of another country.Social implicationsAn implicit assumption in the press is that COVID-19 caught everyone by surprise, and that executives foolishly ignored the risks of outsourcing to China and are now paying the price. However, noted scholars and epidemiologists have been warning of the threats of pandemics since the severe acute respiratory syndrome (SARS) virus. The pundits would further posit that in their pursuit of low-cost production, global corporations made naive assumptions that nothing could disrupt them. Both the firms the authors have interviewed had to close plants to protect their workforce. It was indicated in the cases the authors are developing that it is going to take manufacturers on average one month to recover from 4–6 days of disruption. These companies employ many thousands of people, and direct and ancillary workers are now temporarily laid off and face an uncertain future as/when they will recover back to normal production.Originality/valueUsing the constructal law of physics, the authors seek to provide guidance to future scholarship on global supply chain management. Further, through two case studies, the authors provide the first insight from two senior VPs from two leading multi-national corporations in their respective sectors being disrupted by COVID-19. This study is the first indication to how this and recent disruptive events will impact on the design of future global supply chains. Unlike the generic work, which has recently appeared in HBR and Forbes, it is grounded in real operational insight.


2020 ◽  
Vol 27 (5) ◽  
pp. 1717-1737
Author(s):  
Reza Salehzadeh ◽  
Reihaneh Alsadat Tabaeeian ◽  
Farahnaz Esteki

PurposeThe purpose of this study is to examine the impacts of different forecasting methods (judgmental, quantitative and mixed forecasting) on firms' supply chains and competitive performance.Design/methodology/approachWorking with three groups of manufacturing companies, we explore the consequences of judgmental, quantitative and mixed forecasting methods on firms' competitive performance in supply chains. The validity of constructs and path relationships was examined using structural equation modeling (SEM).FindingsOur findings indicate that supply chain efficiency influences both cost reduction and customer satisfaction. In addition, the three dimensions of supply chain performance are shown to be direct antecedents of competitive performance. Our empirical results reveal that although all studied forecasting methods meaningfully influence supply chain performance, the mixed method, compared to the other two methods, has greater capabilities to enhance supply chain performance.Originality/valueThis research provides originality and insight into supply chain practices through forecasting methods to improve competitive performance.


2011 ◽  
Vol 58-60 ◽  
pp. 2141-2146
Author(s):  
Xiao Di ◽  
Bao Xing

Based on demand uncertainty, the paper studies inventory management decision of two competing supply chains from the perspective of customer service. The paper mainly discusses two different inventory strategies, which are widely used, that is, consignment stock and VMI, and analyzes the optimal policies under three competitive scenarios, which consist of using consignment stock in both supply chains (CC mode), using VMI in both supply chains (DD mode), and using consignment stock in one supply chain but VMI another (VC mode). The paper compares equilibrium inventory level and profit of supply chain in different competitive modes, and concludes that both supply chains use VMI is equilibrium, which means that when manufacturers have right to choose inventory management policy, they prefer VMI. But it isn’t paradoxical with the phenomenon that consignment stock is common in reality, because manufacturers are forced to use consignment by retailer’s channel power.


Sign in / Sign up

Export Citation Format

Share Document