Table of Content

    20 November 2021, Volume 29 Issue 11 Previous Issue    Next Issue
    The Volatility Estimation and VaR Measurement of China’s Copper Future Market: Based on Realized HAR GARCH Model Incorporating Generalized Realized Measures
    CAI Guang-hui, XIANG Lin
    2021, 29 (11):  1-12.  doi: 10.16381/j.cnki.issn1003-207x.2020.0763
    Abstract ( 439 )   PDF (1802KB) ( 550 )   Save
    As China's copper futures market continues to expand, accurate estimation of the volatility of copper futures prices is of particular interest to academics.In this paper, using the high-frequency data samples of copper futures in Shanghai Futures Exchange, the Realized GARCH model and the Realized HAR GARCH model involving different types of realized measures are established under the skew-t distribution to forecast the volatility of returns and the daily VaR.Besides using the conventional realized measures as our benchmarks, the generalized realized measures are introduced into the models. Then, through the in-sample fitting and out-of-sample rolling prediction, likelihood function, VaR posterior tests, and loss function MCS test are applied to compare the results of the models on volatility estimation and evaluate the forecasting effects of the VaR.
    References | Related Articles | Metrics
    Dynamic Portfolio Forecasting of High-dimensions Exchange Rate Assets Under Structure Break
    CHEN Zhan, HUANG Xun, YAN Xiao-feng
    2021, 29 (11):  13-22.  doi: 10.16381/j.cnki.issn1003-207x.2020.0166
    Abstract ( 298 )   PDF (1826KB) ( 461 )   Save
    In recent years, there are some complex typical characteristics of financial market, such as structural break and risk contagion. These characteristics may bring great challenges to risk management and investment portfolio, and structural break in financial market is the key to financial risk contagion, whereas risk contagion is a tough problem that should be solved urgently in the research of investment portfolio. In this paper, the exchange rate of 9 major international currencies against the US dollar is taken as the research object. Firstly, Hidden Markov Model (HMM) is constructed to predict the structure break of exchange rate assets according to the characteristics of structural break that may occur in the exchange rate market, and then dynamic R-Vine Copula model is constructed to predict the risk contagion relationship of exchange rate assets, combined with the the risk contagion relationship that may be induced by structural break between exchange rate assets. Finally, based on the research results of structure break and risk contagion, portfolio exchange rate assets screened out, and a time-varying portfolio forecasting model constructed. The empirical results showed that: HMM model can effectively depict the structure break in exchange rate assets; dynamic R-Vine Copula model can more effectively depict the risk contagion relationship between exchange rate assets; dynamic portfolio forecasting model based on the relationship between structure break and risk contagion has the advantages of reducing portfolio risk and improving portfolio forecasting return.Therefore, an operable research scheme is provided for structure break and risk contagion in financial market, risk supervision departments and institutional investors.
    References | Related Articles | Metrics
    Multi-factor Asset Selection Strategy Based on Sparse Low-rank Ensemble Prediction under Graph Embedding
    LI Ai-zhong, REN Ruo-en, LI Ze-kai, YU Le-an
    2021, 29 (11):  23-32.  doi: 10.16381/j.cnki.issn1003-207x.2020.0076
    Abstract ( 265 )   PDF (1253KB) ( 298 )   Save
    Faced with a large number of uncertainties in the financial market, how to rationally choose effective pricing factors and construct a scientific asset pricing system has always been one of the core issues in financial theory research. The method of graph embedding, based on the sparse representation and low rank representation strategies, is used to deeply mine the inherent structure hidden in the data set, and an integrated learning strategy is constructed that can simultaneously reveal the local structure information and global structure information of the data in order to achieve different dimensions of Multi-source data fusion.Based on the theory of CAPM and APT, a quantitative multi-factor portfolio selection model is constructed by integrating learning methods,and the gradient boosting decision Tree method, convolutional neural network, time series and support vector machine are representatively selected to perform combined prediction.It is optimized by the sparse low-rank graph approximation least squares vector regression integration strategy.At the same time, a sparse low-rank model is constructed that can reveal both local and global structural information of the data, thereby learning to obtain a more accurate representation of multi-source data and high-dimensional data in the feature subspace.The empirical results show that the sparse low-rank strategy based on integrated prediction has stronger securities selection ability and higher excess return rate.The non-linear prediction method using machine learning is more conducive to revealing the complex characteristics of financial system. The empirical conclusion has important guiding significance for portfolio management.
    References | Related Articles | Metrics
    Research on Investment Strategy of Maritime Supply Chain Based on Green Investment Efficiency
    LIU Jia-guo, ZHAO Hui-da, LI Jian
    2021, 29 (11):  33-44.  doi: 10.16381/j.cnki.issn1003-207x.2019.1898
    Abstract ( 379 )   PDF (1900KB) ( 406 )   Save
    Under the background of increasingly strict environmental policy constraints, green investment has become one of the means for port and shipping enterprises to improve their competitive advantages. The investment of enterprises has an impact not only on their own profit, but also on the profit of other members in the supply chain around the port. The shipping supply chain is taken as the research object and the different scenes of investment are introduced. It analyzes the effect of cost, investment, economy and market of investment efficiency on the port supply chain. Finally, it analyzes the influence of different investment strategies on consumer surplus and social welfare. Therefore, in this paper, a port supply chain model is constructed, in which the port is Stackelberg leader and the carrier is the follower. The four cases are studied respectively: no investment; port investment; carrier investment; the both investment with port and carrier. With discussing and comparing the results, the conclusions are as follows: (1) Port investment of green technology will increasing the cost from supply chain member; (2) When the efficiency of technology investment is gradually improved, the level of green investment is declining, and reducing the cost of green inputs, thus achieving the investment effect of "investing in high efficiency, low input level, and high overall growth"; (3) Whether the carrier or the port investing in green technology will increase the service price of the market. Compared with the non-green technology investment, the green technology will increase the demand of the overall market; (4) From the perspective of consumer surplus, the carrier’s green technology investment will be less than the consumer surplus generated by the port green technology investment, and it will also reduce the adverse effects caused by the price “transfer effect” to a certain extent; (5) From the perspective of social welfare, green investment may lower overall social incomes. The social welfare of carrier investment is better than that of port green investment. However, from the perspective of environmental protection, the government’s policy making has a higher priority, which is conducive to improving environmental benefits. The research results have enriched the research of the green investment of port and shipping enterprises. It can provide a reference for the investment choice of the port supply chain members who reasonably balance the investment efficiency. This also has guiding significance for the development of the green port supply chain.
    References | Related Articles | Metrics
    Switching Cost and Pricing Strategy of Two-sided Platform Based on Consumers’ Salience Preference
    PAN Xiao-jun
    2021, 29 (11):  45-54.  doi: 10.16381/j.cnki.issn1003-207x.2020.2401
    Abstract ( 351 )   PDF (965KB) ( 456 )   Save
    Recently, due to the antitrust investigation of Apple, Google, Amazon and other technology platform enterprises in the United States, and China issued the “Anti-monopoly Guide in the field of platform economy”, the switch cost of platform enterprises has attracted widespread attention. When joining the platform, users need to consider factors such as cross-network externalities, switching costs and prices, and face more complex trade-off decisions. The salience theory holds that consumers generally have trade-offs between goods and services that have differences in multiple attributes, and consumers will have different preferences for different attributes in different scenarios. Bordalo et al put forward the salience theory and studied the salience preference of consumers. Based on the salience theory, this paper aims to study the influence of cross-network externality and consumer salience preference on the pricing strategy and profit of monopoly two-sided platform when there is salience thinking in consumers’ switching cost attribute and price attribute.
    References | Related Articles | Metrics
    Three-party Evolutionary Game and Simulation Analysis of Drug Quality Supervision under the Government Reward and Punishment Mechanism
    ZHU Li-long, RONG Jun-mei, Zhang Si-yi
    2021, 29 (11):  55-67.  doi: 10.16381/j.cnki.issn1003-207x.2019.0481
    Abstract ( 503 )   PDF (3024KB) ( 721 )   Save
    Drug safety concerns the people’s life and health, economic development, social stability and national security. It has always been one of the hot issues that the government and the whole society are focusing on. However, in recent years, various drug safety incidents have been frequently reported, which have revealed many problems such as the lacking of government supervision, imperfect drug testing mechanisms. In recent years, the rapid development of third-party drug testing institutions has not only supplemented government supervision, but also provided technical support for pharmaceutical manufacturers. However, driven by interests, there are phenomena of rent-seeking in drug testing between pharmaceutical manufacturing enterprises and the third-party testing agencies. In order to study how to improve the drug quality supervision mechanism to ensure the quality of drugs and avoid rent-seeking in the process of drug testing, a three-party evolutionary game model among drug manufacturers, third-party drug testing institutions and government regulatory agencies has been constructed. Based on the three-party evolutionary game theory, the evolutionary stability of each participant's strategy choices has been analyzed, the influence of each factor on the choice of three-party strategy has been discussed, and the stability of the equilibrium points in the three-party game system has been further analyzed using Jacobian matrix and Lyapunov’s indirect method. The main results show that: 1) increased incentives and penalties by the government will help enterprises to produce high-efficiency drugs and third-party drug testing institutions to refuse to seek rent, but, increased incentives will not be conducive to the government's own performance of regulatory responsibilities; 2) in order to guarantee the safety of drugs in an evolutionarily stable market environment, the government should set reasonable reward and punishment mechanisms in line with the conditions that the sum of the rewards and punishments of each party is greater than its speculative income, that is the condition that the system has only one evolutionary stable equilibrium point; 3) the accountability of the superior government for the dereliction of duty of the regulatory authorities is of great significance to enhance the stability of enterprises in producing high-efficiency drugs; 4) enhancing the company’s drug sales revenue and increasing the company’s rent-seeking cost are also effective ways to avoid enterprises producing low-efficiency drugs. In addition, the parameters are assigned to numerical values based on the conditions of the evolutionary stability strategies which obtained by the model analysis and combined with the reality. The influence of each element on the evolution of each party’s strategy and the stability of the game system under different conditions has been simulated using the Matlab 2020b software. The simulation analysis verifies the correctness of the model analysis and the effectiveness of the countermeasures and suggestions for improving the government supervision mechanism. In short, this paper puts forward a variety of measures to ensure the stable production of high-effective drugs in enterprises and to eliminate rent-seeking, which is conducive to improving the government’s regulatory strategy to ensure patients’ medication safety.
    References | Related Articles | Metrics
    Research on Short-Term Forecast Model of Agricultural Product Price Based on EEMD-LSTM
    FANG Xue-qing, WU Chun-yin, YU Shou-hua, ZHANG Da-bin, OU Yang-qing
    2021, 29 (11):  68-77.  doi: 10.16381/j.cnki.issn1003-207x.2019.0765
    Abstract ( 418 )   PDF (2672KB) ( 454 )   Save
    Agricultural produces price forecasting is one of the main research issues in the field of agricultural economy, and it is of great interest to many researchers and institutions.A novel method is proposed in this paper for agricultural produces price forecasting based on Ensemble Empirical Mode Decomposition (EEMD) method and Long Short-Term Memory (LSTM) network. First, the original price series is decomposed by EEMD to several IMF subsequences and one residual sequence. Then, the fine-to-coarse method is used to reconstruct the IMF subsequences into high frequency item and low frequency item. Finally, the original price series, high frequency item, low-frequency item and residual sequence are taken as input features to train the LSTM network, so as to construct an EEMD-LSTM combined forecasting model.
    References | Related Articles | Metrics
    Research on the Product Update Strategy Considering Quality Level
    LI Nai-liang, HE Yi, LI Yu-peng, ZHANG Chang, GUO Shao-ying
    2021, 29 (11):  78-87.  doi: 10.16381/j.cnki.issn1003-207x.2018.0054
    Abstract ( 250 )   PDF (2075KB) ( 396 )   Save
    The primary issue faced in product update process is how to design a new product quality level. Although the high quality level can expand user markets, its high price factor will reduce customers' willingness to buy, reduce sales, and compete with low-priced old products. Different quality levels of product update correspond to different profits. Excessive quality levels of products can lead to lower profits. The studied problem in this paper is how to determine the optimal value of the quality level in the stage of product update in order to maximize the sales profit.
    References | Related Articles | Metrics
    Study on the Impact of Different Government Subsidy Strategies on Single/Double Recycling Channels
    XIA Xi-qiang, ZHU Qing-hua
    2021, 29 (11):  88-98.  doi: 10.16381/j.cnki.issn1003-207x.2019.1240
    Abstract ( 324 )   PDF (1910KB) ( 389 )   Save
    The rapid development of technology makes the product life cycle shorter and shorter, and replacement more accelerate. Thus, the recycling of waste products has become the focus of society and enterprises. The government adopts the subsidy strategy in order to promote the recycling of waste products, and it could participate in the recycling of waste products through two subsidy strategies, one is to subsidize recyclers, and the other is to subsidize processors. In the recycling process of waste products, there are two common modes, one is single-channel recycling, and the other is dual-channel recycling. In order to analyze the impact of different government subsidy strategies on the two recycling models and establish the optimal subsidy model,the single/double channel recycling game model isconstructed. Basing the game model, the influence of government subsidies on the recycling channel decision variables, recycling quantity and income is comparably analyzed, and the optimal recycling mode boundary conditions is established. The main research results are as follows: the different subsidy targets of government does not affect the amount of waste product recycling when it is the single channel recycling; government giving subsidies to the processors is optimal when it is the dual channel recycling; whether it is single-channel or dual-channel recycling, the processors could get government subsidy through reduce the unit price of waste product entrusted; when the government subsidy amount is greater than a certain threshold, the single-channel recycling mode is better than the dual-channel recycling mode, conversely, the dual-channel recycling is optimal.
    References | Related Articles | Metrics
    Retailer-Dominated Pricing Decision of Cross-Border Dual-Channel Supply Chain under Tariff and Cost Changes
    LIANG Xi, LIANG Lun-hai
    2021, 29 (11):  99-110.  doi: 10.16381/j.cnki.issn1003-207x.2018.1534
    Abstract ( 220 )   PDF (2322KB) ( 276 )   Save
    With the advancement of economic globalization and the continuous improvement of transnational logistics and payment technologies, China’s transnational trade has ushered in a golden period of rapid development. However, due to the growing trade conflict between China and the United States, high tariffs have led to a significant increase in the cost of product transactions, and China’s cross-border supply chain development is facing severe challenges. Thus, the optimal pricing and equilibrium decision-making of cross-border supply chains under tariff changes needs to be resolved. In this paper, a multinational supply chain game model consisting of a domestic manufacturer, a multinational manufacturer and a domestic retailer is constructed, in which the retailer is the leader of Stackelberg. By introducing tariffs, international transportation costs and other factors, the impact of tariff changes on the pricing of multinational supply chain products and the profit of each member is explored. The results show that: As offline channel trade tariff increases, the wholesale price of domestic manufacturer's product A will increase, while the direct selling price of product A and the wholesale price of overseas manufacturer's product B will decrease, and the impact of tariff changes on retailer pricing decisions is related to consumer price sensitivity coefficient. The increase in domestic tariffs will increase the profit of domestic manufacturers and reduce the profits of overseas manufacturers. The change in retailer profits is also affected by the consumer price sensitivity factor: only when the consumer price sensitivity coefficient is large, the tariff increase of domestic products can improve retailer’s profits. Besides, with the increase of international transportation costs, the wholesale prices of products A and B will decrease, the retail prices of products A and B will increase, and the profits of members in the supply chain will decrease. Theoretical system of the global supply channel supply chain further and these conclusions provide a basis for decision making for corporate decision-making in global supply chain members.
    References | Related Articles | Metrics
    Research about the Effects of CSR on Supply Chain Emission Reduction Decision-making and Government Subsidy Efficiency
    LIN Zhi-bing, BAO Lei
    2021, 29 (11):  111-121.  doi: 10.16381/j.cnki.issn1003-207x.2019.2132
    Abstract ( 312 )   PDF (1658KB) ( 566 )   Save
    In order to investigate the effects of retailer’s corporate social responsibility (CSR) on supply chain emission reduction decision-making and government subsidy efficiency, a three-stage Stackelberg game model involving government decision-makers is constructed. At firstly, in the precondition of consumer low-carbon preference and the implementation level of retailer’s CSR, the decentralized decision-making model is discussed. The analysis of the equilibrium results shows that: (1) the enhancement of the implementation level of retailer’s CSR results in the improvement of the emission reduction of manufacturers, the increment of manufacturer’s profit and social welfare, while the effects on retailer’s profit and the overall profit of the supply chain also depend on the coefficient of emission reduction efforts. (2) Government subsidy can increase the emission reduction of manufacturers and the profits of channel members. Further, retailers can improve the utilization efficiency of government unit subsidy through the intensive implementation of CSR, making the effect of government advancing the emission reduction and the profit more remarkable. By contrast, the retailer’s profit increment, promoting by government subsidy, is significant under the circumstance of the lower implementation level. Then comparing the optimal profit of the channel under the centralized and decentralized decision-making model, a two-part tariff and cost sharing contract is proposed, and it is proved that the contract can induce the supply chain coordination. Finally, on this basis, the research is extended to the situation of manufacturer implementing CSR and the new goals of the government. Through theoretical and numerical analysis, the impact of CSR behavior on supply chain emission reduction decision-making is discussed in detail to provide reference for the relevant decision-making of government and low-carbon supply chain.
    References | Related Articles | Metrics
    Contract Design of ‘Online to Offline’ for Dual-Channel Supply Chain under Bidirectional Fairness Concerns
    LI Chong-lian, FAN Ding-xiang, WANG Xiao-lei
    2021, 29 (11):  122-133.  doi: 10.16381/j.cnki.issn1003-207x.2019.0080
    Abstract ( 239 )   PDF (2706KB) ( 302 )   Save
    Aiming at the issue of the consumer channel preference and bidirectional fairness concerns in the dual-channel supply chain, how to effectively integrate the platform advantages of online channel providers with the experience advantages of offline channel providers is explored. Based on the consumer preference, the coexist situation of bidirectional fairness concerns among manufacturers, online and offline channel providers is considered. It is necessary to further explore the difference between centralized and decentralized dual-channel supply chains in pricing decisions. The contract for wholesale price discounts and sharing service costs is introduced to coordinate various entities in the supply chain. The results show that:(1) The double marginalization effect of the dual-channel supply chain will be further aggravated by the factors of bidirectional fairness concerns. (2) The horizontal and vertical fairness concerns have different influence trends on the utility of manufacturers and channel providers, and can respectively strengthen and weaken the bargaining power of consumers. (3) When the consumer channel preference coefficient is within a certain interval, the increase of online channel and manufacturer’s profit can make up the losses of offline channel providers. (4)By setting the contract ratio within a certain range, it can promote manufacturers, online and offline channel providers to form a complementary and collaborative win-win situation.
    References | Related Articles | Metrics
    Three-Party Evolutionary Game Analysis of P2P Network Lending Based on Nonlinear System Stability Theory
    DENG Chun-sheng
    2021, 29 (11):  134-145.  doi: 10.16381/j.cnki.issn1003-207x.2019.1007
    Abstract ( 262 )   PDF (1116KB) ( 300 )   Save
    Online P2P lending is a financial innovation model that provides information intermediary services for borrowers and investors to achieve direct lending, where the Internet is the main channel. Since the establishment of the Ppdai in China in 2007, online P2P lending has grown rapidly in China, attracting many users and facilitating a large number of lending transactions. However, due to the lack of awareness of risk management, the lack of regulatory measures and inadequate system design, the "violent thunder" incidents in China’s online P2P lending industry are endless. Therefore, perfecting its legal regulation system is the research hotspot in the current financial field.
    References | Related Articles | Metrics
    Research on Quality Incentive Contracts of Dairy Supply Chain Considering Customer Utility and Time-Varying Quality
    HUA Lian-lian, DENG Si-jie, WANG Jian-guo, YUE Xiao-hang
    2021, 29 (11):  146-157.  doi: 10.16381/j.cnki.issn1003-207x.2019.0488
    Abstract ( 211 )   PDF (2135KB) ( 246 )   Save
    “Quality, safety and green development” has become the consensus of the development of the dairy industry. If there is no reasonable interest distribution mechanism to support, the enthusiasm of processing enterprises would becombat in the face of high quality input costs. In this study, the quality of dairy products is defined by the concept of satisfactory quality. Considering the influence of time on the quality of dairy products, a “time-varying quality” functionis built with productivity, behavioral and environmental perspectives. With the consideration of the time sensitivity of customer utility, the quality markup and time-varying quality characteristic of dairy products and the revenue management of producers are combined.Two incentive mechanisms, the “wholesale price + revenue sharing” contract and the “revenue sharing + quality input cost sharing” contract, are designed to stimulate the main enterprises in the dairy supply chain to increase the input in product quality.
    References | Related Articles | Metrics
    Optimal Group-buying Strategies for Competing Retailers with Fairness Concern Behavior
    ZHOU Yong-wu, YANG Li-fang, CAO Bin, ZHONG Yuan-guang
    2021, 29 (11):  158-169.  doi: 10.16381/j.cnki.issn1003-207x.2019.1287
    Abstract ( 214 )   PDF (2667KB) ( 419 )   Save
    Group-buying strategy is widely used in the procurement model of the enterprise, which is beneficial for enterprises to improve bargaine power, reduce purchase cost and so on. Most of the existing studies have assumed that supply chain members are completely rational, ignoring that decision makers are often pursuing fairness. A two-level supply chain consisting of one supplier and two competing retailers is studied by considering the decision maker’s behavioral characteristics—fair concerns and quantity discount contracts into the traditional model. On this basis, the decision-making model of two competing retailers ordering from the same supplier is established. Under the premise of supplier fairness neutrality and retailer performance fairness,the retailers’ optimal strategies and maximum utilities are obtained by using the optimization theory. In the case of the symmetry of the two retailers, the influence of the retailers’ optimal ordering strategy selection, fair concern parameters, quantity discount ratio, competition intensity and bargaining power on the optimal order quantities are theoretically analyzed. The results show that the competition intensity and quantity discount ratio are positively correlated with the optimal order quantities of the retailers. The influence of bargaining power and fairness concern parameters on the retailer’s order quantity are related to the quantity discount ratio. Finally, numerical examples are conducted to analyze the heterogeneous and nonlinear quantity discount ratios of two retailers and the joint purchase by multiple retailers. Our numerical results are consistent with the theoretical analysis obtained in the paper.
    References | Related Articles | Metrics
    Bi-level Programming Model for Multi-source Emergency Materials Procurement Considering Supply Risks
    DONG Yin-hong, ZHENG Qi, LI Long
    2021, 29 (11):  170-178.  doi: 10.16381/j.cnki.issn1003-207x.2019.Y-04
    Abstract ( 252 )   PDF (1419KB) ( 346 )   Save
    In recent years, with the increase of the frequency of various natural disasters, the procurement of relief items has become more and more important as the basic work of emergency management. The occurrence of disasters has an important impact on the supply of emergency supplies.Therefore, the supply risk under different disaster scenarios is considered, selects multiple suppliers are selected to buffer supply risks, and then a bi-level programming model is built, in which the upper layer aims to maximize the revenue of the entire supply chain system and the lower layer aims to minimum supply risk. The bi-level programming model is used to study the allocation of emergency supplies purchase orders under different disaster scenarios to determine the different suppliers’ Optimal purchase volume.Subsequently, a city flood disaster is used as an example to prove the feasibility of the model, it is found that as supply risks increase, so does the amount of government procurement before the disaster. Therefore, when allocating purchase orders, the government can focus on pre-disaster procurement. Pre-disaster procurement of emergency supplies equivalent to the government’s storage capacity limits can both reduce procurement costs and ensure disasters. The supply of emergency materials after the accident will not cause waste of emergency materials. In addition, the government should also allocate orders according to the supplier’ssupply risks. The smaller the risk, the more orders the supplier will be allocated.
    References | Related Articles | Metrics
    Joint Replenishment Strategy of Vending Machines in Unmanned Retail Industry
    CAO Yu, XU Rong-liang, HU Han-li, LI Qing-song
    2021, 29 (11):  179-190.  doi: 10.16381/j.cnki.issn1003-207x.2019.0515
    Abstract ( 293 )   PDF (1549KB) ( 449 )   Save
    With the upgrading of consumption and the increase in personalized demand, unmanned retail formats have gradually become the mainstream of China’s retail industry. The development of China’s unmanned retail industry is taken as the background, and a retail firm’s decision to replenish the vending machine is taken as a case to explore the problem of multi-product joint replenishment of the vending machine in the unmanned retail industry. The results show that companies tend to replenish when there are fewer products left. The remaining products are often the smallest projected area so that the same area can accommodate the largest number of products. Comparing the optimal replenishment time with the average replenishment cost found that extending the replenishment time can reduce the average replenishment cost. At the same time, it was found that when the replenishment threshold is larger, the fixed replenishment cost is lower, or the vending machine capacity is smaller, the optimal replenishment time will decrease, and when the replenishment threshold, fixed replenishment cost or vending machine capacity increases, the average replenishment costs will increase. Analyzing the impact of different cost changes on average costs, it is found that changes in unit costs will cause an increase in average replenishment costs. When the unit inventory holding cost changes, the optimal replenishment strategy will shift to products with a unit inventory holding cost reduced to a certain degree or to the product with the lowest projected area, that is, the smallest amount that can be accommodated in the same area. Through the research, it can provide a reference for the firm to select the product type of the vending machine, and provide a decision reference for the firm to determine the optimal replenishment time and quantity.
    References | Related Articles | Metrics
    Online Interpersonal Group-buying Based on Social Relationship
    HU Feng-ying, ZHOU Zheng-long
    2021, 29 (11):  191-202.  doi: 10.16381/j.cnki.issn1003-207x.2019.1892
    Abstract ( 384 )   PDF (2446KB) ( 486 )   Save
    Based on the innovative marketing mode with two sale prices, over the last two years, online interpersonal group buying mode have rapidly become popular among many sellers and consumers in China. However, in relevant literature, there aren’t the theoretical analysis relating to the interpersonal group-buying mechanism or comparative studies of interpersonal group buying and traditional selling (such as uniform-pricing trading) have been found. In order to fill this research gap, the uniform-pricing trading for comparison is added in order to explore differences between interpersonal group buying and uniform-pricing trading in terms of profitability. In the research process, a theoretical model is provided to compare and analyze the impact of online interpersonal group-buying mode and the unified price mode (i.e., the normal mode) on the sellers, and reference for the sellers is provided to implement precision marketing. The consumers’ social relationship is considered and the consumers are subdivided, and then the cost coefficient of social relationship (i.e., social cost) and the impact of potential market demand on price and revenue are analyzed. The results show that, under certain conditions, the optimal price in the normal mode is between the optimal interpersonal group-buying price and the optimal normal price in the interpersonal group-buying mode. The optimal revenue in the normal mode is less than that in the interpersonal group-buying mode. That is, the interpersonal group buying mode can bring greater benefits to merchants, but the interpersonal group buying mode is only a supplement to the normal mode. Further, as the social cost difference between the two types of consumers gradually decreases or the potential market demand of consumers who prefer to interpersonal group-buying trading increases, the advantage of the interpersonal group-buying mode is gradually weakened. Therefore, it is suggested that the interpersonal group-buying platform cooperate with social platform (such as WeChat) to build a social e-commerce mode. The purpose is to reduce the social cost of consumers, so as to attract consumers to enter the interpersonal group-buying platforms to purchase goods, and achieve “sellers, platforms and consumers” multi-win. At last, it is suggested that the interpersonal group-buying platforms should subdivide the consumers in the second or third time and develop new market segments.
    References | Related Articles | Metrics
    A Consensus Model for Group Decision Making under the Influence of Empathy
    YAO Sheng-bao, GU Miao
    2021, 29 (11):  203-214.  doi: 10.16381/j.cnki.issn1003-207x.2020.0907
    Abstract ( 329 )   PDF (2268KB) ( 384 )   Save
    In group decision making, the social relations among group members and the structural characteristics of their social networks are the important factors that affect the consensus reaching process and ranking of alternatives. Empathetic relation is an important social relationship in some group decision-making problems. However, there are few researches on empathetic group decision making so far. In this paper, empathetic relation is introduced into group decision making based on preference relations, and a consensus model for group decision making in empathetic network environment is proposed. First of all, based on different empathy hypotheses, a local empathetic model and a global empathetic model are constructed to determine the evolution results of the intrinsic preferences of group members under the influence of empathy. Secondly, a feedback mechanism guided by empathetic relations is designed for the consensus reaching process. The feedback mechanism can achieve continuous improvement of group consensus level at the level of individual preference through iterative adjustment of intrinsic preference relations until it reaches acceptable group consensus level. Finally, the influence of empathy on group consensus is analyzed by numerical simulation. The experimental results show that: the empathy relationship between group members improves the level of group consensus, and the global empathy relationship is more conducive to the achievement of group consensus than the local empathy relationship; the structure of empathy network and group size are important factors affecting the consensus reaching process in the context of empathetic network. The research results have some reference value for the study of social network group decision making, and can also provide method support for the actual group decision-making.
    References | Related Articles | Metrics
    Optimal Control Model of Social Network Public Opinion Considering Thought Time-Lag
    GU Qiu-yang, WU Bao, CHI Ren-yong
    2021, 29 (11):  215-223.  doi: 10.16381/j.cnki.issn1003-207x.2020.1718
    Abstract ( 227 )   PDF (2421KB) ( 293 )   Save
    In the circumstance of developing information technology, various and complicated information are ubiquitous at any time on the social networks, of which the negative messages are also increasingly growing at a fast rate, having a serious impact on the network safety and social stability. As a result, it is pressing to design an effective model to control the spread of the negative information. Time lag is a common thing in nature. In the process of spreading public opinions on the social network, some users may give a response after consideration. Among the existing studies, most do not take these thinkers’ time lag into account. Because of this, an optimal control model of public sentiment spread is proposed, with time lag considered. First of all, a model of public sentiment spread, which involves thinkers, has been built based on the classical epidemic model. A systematic dynamics analysis is made in terms of steady state and local stability. At the same time, Hopf bifurcation under the extreme threshold is discussed. Secondly, sensitivity analysis is conducted for the parameters in the model. With Pontryagin maximum principle and the attack mechanism of opposing public opinion introduced, the optimal control model concerning public sentiment spread is designed according to the optimizing control theory, aiming to minimize the density of people following the negative public sentiment and the controlling cost. The experiment indicates that this model can effectively control the spread of public sentiments in social networks. The system is in a stable state when thinkers need more time to give a response as well as when the attack of opposing public opinions spread at the fastest pace via the media and experts. Besides, the optimal control model is able to let the attack information of opposite public opinion spread effectively in a short time with the minimum cost when there is an event of public opinion.
    References | Related Articles | Metrics
    Who Gambles in the Market? A Study on Mutual Funds’ Preferences for Lottery-like Stocks
    XIANG Cheng, YANG Jun
    2021, 29 (11):  224-236.  doi: 10.16381/j.cnki.issn1003-207x.2019.1299
    Abstract ( 276 )   PDF (1282KB) ( 258 )   Save
    Recent studies have shown that investors prefer stocks with lottery features (lottery preferences hereafter), which have relatively low expected returns but a small chance of huge pay-offs. However, most studies in this field focus on individual investors, assuming that institutional investors are rational and professional market participants and do not gamble in the market.
    References | Related Articles | Metrics
    Optimal Model and Application for Terrorist Interdiction Network Design under Fuzzy Environment
    XIANG Yin
    2021, 29 (11):  237-248.  doi: 10.16381/j.cnki.issn1003-207x.2019.0597
    Abstract ( 194 )   PDF (3415KB) ( 286 )   Save
    Since the September 11 attacks, terror has become a major threat in the world. Recently, with the implementation of the Belt and Road strategy, the cooperation between China and other countries are becoming more and more frequently, which increases the risk for terrorist invasion. In order to prevent terrorists abroad from invading into China, the government can design an effective interdiction network in the border area.
    References | Related Articles | Metrics