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1.
对废旧产品回收再利用既减少环境污染,又能节约社会有用资源,闭环供应链的研究受到学术界的广泛重视。利用生产函数,在稳定型和风险型市场背景下构造了六类非博弈型创新研究和广告合作的二级闭环供应链模型,并采用多种数学方法给出了模型最优解的存在性与求解方法。信息不对称是供应链的重要特点,提高信息共享程度是未来供应链发展的根本趋势。本文首先根据如下假设进行建模,即创新投入能使再制品单位成本降低,广告投入带来废旧产品回收率提高和再制品销售量的增加;其次,模型求最优解过程中强调合作,提出了应制定内部利润分配规则和联合对外行动决策两套契约的供应链管理思想。各成员放弃(至少是减少)内部“斗智斗勇”,按照保证供应链整体利润最大化的原则确定各方的最佳投资额;最后,对模型进行了仿真分析,应用实例说明了在同样市场背景和创新条件下合作比博弈通常能给供应链带来大得多的利润。另外,无论在稳定型还是风险型市场背景下,平等合作与主从合作供应链总利润相同。因此,主企业要尽量对较弱企业进行扶持,提高供应链整体对外竞争能力。  相似文献   

2.
We introduce methods for estimating nonparametric, nonadditive models with simultaneity. The methods are developed by directly connecting the elements of the structural system to be estimated with features of the density of the observable variables, such as ratios of derivatives or averages of products of derivatives of this density. The estimators are therefore easily computed functionals of a nonparametric estimator of the density of the observable variables. We consider in detail a model where to each structural equation there corresponds an exclusive regressor and a model with one equation of interest and one instrument that is included in a second equation. For both models, we provide new characterizations of observational equivalence on a set, in terms of the density of the observable variables and derivatives of the structural functions. Based on those characterizations, we develop two estimation methods. In the first method, the estimators of the structural derivatives are calculated by a simple matrix inversion and matrix multiplication, analogous to a standard least squares estimator, but with the elements of the matrices being averages of products of derivatives of nonparametric density estimators. In the second method, the estimators of the structural derivatives are calculated in two steps. In a first step, values of the instrument are found at which the density of the observable variables satisfies some properties. In the second step, the estimators are calculated directly from the values of derivatives of the density of the observable variables evaluated at the found values of the instrument. We show that both pointwise estimators are consistent and asymptotically normal.  相似文献   

3.
In this article, we study how the operational decisions of a firm manager depend on her own incentives, the capital structure, and financial decisions in the context of the newsvendor framework. We establish a relationship between the firm’s cost of raising funds and the riskiness of the inventory decisions of the manager. We consider four types of managers, namely, profit, equity, firm value, and profit‐equity maximizers, and initially assume that they may raise funds to increase the inventory level only by issuing debt. We show that the shareholders are indifferent between the different types of managers when the coefficient of variation (CV) of demand is low. However, this is not the case when the CV of demand is high. Based on the demand and the firm’s specific characteristics such as profitability, leverage, and bankruptcy costs, the shareholders might be better off with the manager whose compensation package is tied to the firm value as opposed to the equity value. We, then, extend our model by allowing the manager to raise the required funds by issuing both debt and equity. For this case we focus on the equity and firm value maximizer managers and show that our earlier results (for the debt only case) still hold subject to the cost of issuing equity. However the benefit of the firm value maximizer manager over the equity maximizer manager for shareholders is considerably less in this case compared to the case where the manager can only issue debt. The Board of Directors can take these factors into consideration when establishing/modifying the right incentive package for the managers. We also incorporate the notion of the asymmetric information to capture its impact on the board of directors’ decision about the managers’ incentive package.  相似文献   

4.
本文根据影响子公司角色转变的因素,将子公司的角色根据每种因素的强弱不同分为八种类型,即起步者、淘汰者、办事员、支持者、小诸侯、贡献者、直辖领袖和自由领袖.根据该子公司角色划分方法和演化路径分析方法,本文深入研究了一家跨国公司在华子公司-BEC公司的角色演化情况,研究证实了本文得出的角色划分方法和演化路径分析框架的适用性,也得到了跨国公司在华子公司的一个具体演化路径.  相似文献   

5.
This paper presents a test of the exogeneity of a single explanatory variable in a multivariate model. It does not require the exogeneity of the other regressors or the existence of instrumental variables. The fundamental maintained assumption is that the model must be continuous in the explanatory variable of interest. This test has power when unobservable confounders are discontinuous with respect to the explanatory variable of interest, and it is particularly suitable for applications in which that variable has bunching points. An application of the test to the problem of estimating the effects of maternal smoking in birth weight shows evidence of remaining endogeneity, even after controlling for the most complete covariate specification in the literature.  相似文献   

6.
We provide the first analysis of altruism in networks. Agents are embedded in a fixed network and care about the well‐being of their network neighbors. Depending on incomes, they may provide financial support to their poorer friends. We study the Nash equilibria of the resulting game of transfers. We show that equilibria maximize a concave potential function. We establish existence, uniqueness of equilibrium consumption, and generic uniqueness of equilibrium transfers. We characterize the geometry of the network of transfers and highlight the key role played by transfer intermediaries. We then study comparative statics. A positive income shock to an individual benefits all. For small changes in incomes, agents in a component of the network of transfers act as if they were organized in an income‐pooling community. A decrease in income inequality or expansion of the altruism network may increase consumption inequality.  相似文献   

7.
丰景春  张跃  丰慧  张可  李明  薛松 《中国管理科学》2019,27(10):189-197
项目群工期延误诊断是项目群进度目标控制的一项重要任务。总时差可用于判断项目群中某项工作延误对项目群总工期的延误程度,但没有解决某项工作延误对其自身合同项目和后续合同项目工期延误程度的判断问题。本文根据多项目管理和项目群管理理论,通过引入项目群子网络,研究并构建了基于子网络的项目群结构。在此基础上,运用关键路径法(CPM),系统地研究了因子网络中合同项目某工作工期延误对自身子网络以及项目群中后续子网络工期的影响,提出了子网络后主链定理以及前主链总时差定理,从而实现子网络视角下项目群合同项目工期延误的诊断分析。结合算例进行了具体阐述与应用。最后就如何应用人工智能算法实现项目群进度及其影响因素进行实时监控提出研究思路。本文研究成果为子网络承包商的工期延误责任划分以及索赔提供依据。  相似文献   

8.
合作创新具有实现资源互补,降低创新风险,提高创新成功可能性的优势,但是在实践中企业间的合作关系却难以保持稳定性。本文基于有限理性假设,改变传统的期望效用理论,引入前景理论中的参照点概念,分析创新主体的效用,构建合作创新博弈收益感知矩阵,并基于该矩阵对合作创新博弈双方的行为进行演化博弈分析,为保持合作创新的持续性提出建议。研究表明,企业对创新收益的感知价值、合作创新成本、收益分配和成本分担等因素是合作稳定性的重要影响因素,增强企业对长期的战略性合作创新收益的感知,引导企业建立正确的创新风险认知,控制合作创新的交易成本等措施将有利于增强合作创新的稳定性。  相似文献   

9.
构建风险视域下研发网络企业自适应行为规则,基于SIS模型构建研发网络风险传播模型,运用数值仿真的方法通过改变模型参数探索在考虑自适应行为的情况下研发网络的风险传播规律,研究结果表明:(1)C1策略增强了网络的层次性和社团强度,一定程度上抑制了研发网络中风险的传播;C2策略下节点之间新连接的建立更多是基于临近性的考量,容易陷入路径依赖和能力陷阱;(2)研发网络企业的自适应行为会导致社团强度的涨落,平均路径长度的下降以及平均聚类系数的增长充分体现出C1策略的有效性。(3)C1策略下,断边概率p与I*之间呈现"U"型相关关系;在C2策略下随着断边概率p的增长I*逐渐降低。(4)在C1策略和C2策略下,随着参数ζ的增长I*也随之增长,可知组织依赖水平是研发网络风险传播控制中需要重点关注的因素。本文揭示了在考虑自适应行为的情况下研发网络的风险传播规律,为网络化运作背景下研发网络治理提供理论依据。  相似文献   

10.
We develop a new quantile‐based panel data framework to study the nature of income persistence and the transmission of income shocks to consumption. Log‐earnings are the sum of a general Markovian persistent component and a transitory innovation. The persistence of past shocks to earnings is allowed to vary according to the size and sign of the current shock. Consumption is modeled as an age‐dependent nonlinear function of assets, unobservable tastes, and the two earnings components. We establish the nonparametric identification of the nonlinear earnings process and of the consumption policy rule. Exploiting the enhanced consumption and asset data in recent waves of the Panel Study of Income Dynamics, we find that the earnings process features nonlinear persistence and conditional skewness. We confirm these results using population register data from Norway. We then show that the impact of earnings shocks varies substantially across earnings histories, and that this nonlinearity drives heterogeneous consumption responses. The framework provides new empirical measures of partial insurance in which the transmission of income shocks to consumption varies systematically with assets, the level of the shock, and the history of past shocks.  相似文献   

11.
This article explores the use of an approach for setting default values for the noncancer toxicity, developed as part of the Threshold of Toxicological Concern (TTC), for the evaluation of the chronic noncarcinogenic effects of certain chemical mixtures. Individuals are exposed to many mixtures where there are little or no toxicological data on some or all of the mixture components. The approach developed in the TTC can provide a basis for conservative estimates of the toxicity of the mixture components when compound-specific data are not available. The application of this approach to multiple chemicals in a mixture, however, has implications for the statistical assumptions made in developing component-based estimates of mixtures. Specifically, conservative assumptions that are appropriate for one compound may become overly conservative when applied to all components of a mixture. This overestimation can be investigated by modeling the uncertainty in toxicity standards. In this article the approach is applied to both hypothetical and actual examples of chemical mixtures and the potential for overestimation is investigated. The results indicate that the use of the approach leads to conservative estimates of mixture toxicity and therefore its use is most appropriate for screening assessments of mixtures.  相似文献   

12.
本文使用投资组合理论对养老金统筹账户与个人账户的最优组合策略进行研究。为此,我们首先分析了确定性条件下的账户选择问题,然后,在随机假设下对不同账户的收益进行精算建模,在此基础上构建了养老金账户最优组合模型,最后,对上述模型进行了数值求解。研究表明:(1)统筹账户与个人账户的收益负相关,二者的组合能够形成一个有效的风险对冲机制;(2)混合制的有效边界在现收现付制和累积制的上方,因此,从风险-收益的角度讲,混合制优于单一养老金制度;(3)与最优账户组合相比,现行统筹账户的占比偏高,个人账户占比偏低。本文的政策含义在于,适当的降低现行统筹账户的占比,提高个人账户的占比能够降低养老金账户的风险水平,增加账户的收益。  相似文献   

13.
R&D成果转让合同履约的定量分析:激励对策与优效设计   总被引:1,自引:1,他引:1  
R&D(研究与开发)成果向生产力转化难的问题因研发方利益无保障而普遍存在。本文运用经济对策理论和数量分析方法,对R&D成果转让合同给出定量描述,并在此基础上对实际中常见的三种成果转让情形分别给出了激励受让方履约的合同设计。对三种合同的履约激励相容性给出了证明。对其中两种情形还讨论了使受让方履约与研发方利润最大化或审计成本最小化的双目标优效合同设计,建立了各情形下的双目标激励优效条件。最后通过一个具体例子说明所设计的多期双目标优效合同的可行性及应用。  相似文献   

14.
大量可再生能源和存储设施集中或分布接入电网,缓解了电网的供给压力,但同时也对电力系统安全造成新的威胁。合理使用新能源和可存储设施使之更好为电网服务,是现代电网亟待解决的一个问题。本文对有可存储设备和可再生能源并网的电力系统进行研究,根据可再生能源在实际生活中的情形,将其划分为两类:私人新能源发电和公共新能源发电,其中私人新能源发电可供自身直接使用,多余部分并入电网,而公共新能源发电直接并入电网,然后针对上述复杂情形,结合用户实际需求,以所有用户效用最大化、成本最小化为目标函数,建立优化模型,给出了一种既有可存储设备又有可再生能源复杂并网情况下用户优化用电策略——包括家用电器、新能源、以及存储设备充放电策略。对模型的性质进行研究,考虑到模型是凸规划,强对偶成立,用拉格朗日对偶算法给出了模型的解。求解过程中,由于目标函数是非光滑的,采用光滑化的技术将目标函数光滑化,将非光滑问题转化为光滑问题,进一步利用拟牛顿下降法求解。该策略能确保新能源得到优先、充分利用,体现用户效用最大化、成本最小化,同时可以避免由于新能源并网可能会造成电网不稳定情况的出现;光滑化的方法不但适用于本文,经过适当改进后也可适用于其他目标函数为非光滑的情况。仿真结果验证了模型的合理性和算法的可行性。  相似文献   

15.
The aim of this article is to build a methodology allowing the study and the comparison of the potential spread of BSE at the scale of countries under different routine slaughtering conditions in order to evaluate the risk of nonextinction due to this slaughtering. We first model the evolution in discrete time of the proportion of animals in the latent period and that of infectives, assuming a very large branching population not necessarily constant in size, two age classes, less than 1-year-old animals, and adult animals. We analytically derive a bifurcation parameter rho(0) allowing us to predict either endemicity or extinction of the disease, which has the meaning of an epidemiological reproductive rate. We show that the classical reproductive number R(0) cannot be used for prediction if the size of the population, when healthy, does not remain stable throughout time. We illustrate the qualitative results by means of simulations with either the British routine slaughtering probabilities or the French ones, the other conditions being assumed identical in both countries. We show that the French probabilities lead to a higher risk of spread of the disease than the British ones, this result being mainly due to a smaller value of the routine slaughtering probability of the adult animals in France than in Great Britain.  相似文献   

16.
The paper analyzes dynamic principal–agent models with short period lengths. The two main contributions are: (i) an analytic characterization of the values of optimal contracts in the limit as the period length goes to 0, and (ii) the construction of relatively simple (almost) optimal contracts for fixed period lengths. Our setting is flexible and includes the pure hidden action or pure hidden information models as special cases. We show how such details of the underlying information structure affect the optimal provision of incentives and the value of the contracts. The dependence is very tractable and we obtain sharp comparative statics results. The results are derived with a novel method that uses a quadratic approximation of the Pareto boundary of the equilibrium value set.  相似文献   

17.
The attack that occurred on September 11, 2001 was, in the end, the result of a failure to detect and prevent the terrorist operations that hit the United States. The U.S. government thus faces at this time the daunting tasks of first, drastically increasing its ability to obtain and interpret different types of signals of impending terrorist attacks with sufficient lead time and accuracy, and second, improving its ability to react effectively. One of the main challenges is the fusion of information, from different sources (U.S. or foreign), and of different types (electronic signals, human intelligence. etc.). Fusion thus involves two very distinct and separate issues: communications, i.e., ensuring that the different U.S. and foreign intelligence agencies communicate all relevant and accurate information in a timely fashion and, perhaps more difficult, merging the content of signals, some "sharp" and some "fuzzy," some dependent and some independent into useful information. The focus of this article is on the latter issue, and on the use of the results. In this article, I present a classic probabilistic Bayesian model sometimes used in engineering risk analysis, which can be helpful in the fusion of information because it allows computation of the posterior probability of an event given its prior probability (before the signal is observed) and the quality of the signal characterized by the probabilities of false positive and false negative. Experience suggests that the nature of these errors has been sometimes misunderstood; therefore, I discuss the validity of several possible definitions.  相似文献   

18.
公私合作制(PPP)项目的政府动态激励与监督机制   总被引:5,自引:0,他引:5  
徐飞  宋波 《中国管理科学》2010,18(3):167-173
针对PPP基础设施项目建设中激励机制涉及的企业最优努力水平、政府监督及关系契约的预期收益三大因素加以分析;从动态的角度出发,在Holmstrom和Tirole激励模型的基础上,运用委托代理理论设计公私部门两阶段合作的激励合同,通过对不同阶段企业最优努力水平和政府监督奖惩因子的分析,得到影响企业最优努力水平和政府监督奖惩因子的相关因素以及企业两阶段决策中的动态影响;最后分别通过对政府外部监督与企业内在激励的分析,提出PPP项目建设中权变激励的激励机制和方向,从而为PPP项目建设中有效激励合同的设计提供一定的指导。  相似文献   

19.
This study examined the antecedents of job strain (emotional exhaustion, health complaints) and withdrawal behaviour (e.g. lowered organizational commitment) among a cross-sectional sample of 131 academic staff members of the law department of a large Dutch university. Conservation of resources theory (Hobfoll, 1989) provided the theoretical background for this study. Strains and withdrawal behaviours were expected to be most prominent among those who reported having few resources and/or who reported high job demands. Structural equation modelling revealed that this was indeed the case. As predicted, differential patterns of effects emerged for job demands and job resources. Analysis of the effects of four job-specific stressors revealed that especially the structural aspects of a staff member's teaching task (e.g. the number of students in their classes) contributed strongly to perceived job demands. Theoretical and practical implications of the study are discussed.  相似文献   

20.
Social impacts caused by floods and landslides in Portugal in the period of 1865–2010 are gathered in the DISASTER database. This database contains 1,902 hydro‐geomorphologic cases that caused 1,248 fatalities (81% and 19% associated with floods and landslides, respectively). The use of the DISASTER database allowed for: (i) the analysis of the frequency and the temporal evolution of fatal floods and landslides; (ii) the analysis of the spatio‐temporal distribution of fatalities; (iii) the identification of the most deadly flood and landside types; (iv) the verification of gender tendencies in mortalities; and (v) the evaluation of individual and societal risk. The highest number of flood and landslide cases and related mortalities occurred in the period of 1935–1969. After this period, the number of flood and landslide mortalities decreased, although landslide fatalities remained higher than those registered in the period of 1865–1934. The occurrence of flood fatalities was widespread in the country, with an important cluster in the Lisbon region and in the Tagus valley, while fatalities caused by landslides mainly occurred in the north of the Tagus valley. Flash floods caused the majority of fatalities associated with floods, while falls and flows were responsible for the highest number of fatalities associated with landslides. Males were found to have the highest frequency of fatalities. In the case of floods, the majority of fatalities were found both outdoors and inside of buildings in rural areas while fatalities inside buildings were dominant in landslide cases, mostly in rural areas.  相似文献   

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