Differences in Retail Inventory Investment Behavior During Macroeconomic Shocks: Role of Service Level

In this article, we analyze how retailers change their inventory investment behavior in response to macroeconomic shocks. We examine if service level, as measured by the ratio of stockout to inventory holding costs, can explain the differences in observed behavior across retailers. We use data on macroeconomic indicators and quarterly filings of US public retailers from 1985 to 2009 to estimate a dynamic model of short‐ and long‐term impact of macroeconomic shocks on inventory investment. Our results show that retailers with a high service level increase their inventory investment significantly more than those with a low service level during expansion shocks. Conversely, retailers with a low service level curtail their inventory investment significantly more than those with a high service level during periods of economic contractions. Thus, we show that the aggregate change in inventory investment documented in prior macroeconomics research is driven by different sets of retailers, as predicted by newsvendor logic. We draw implications of our findings to retailers as well as their suppliers.     

Heston模型下保险公司和再保险公司的投资与再保险博弈

在同时考虑保险公司和再保险公司利益的前提下,研究了保险公司和再保险公司之间的投资与再保险博弈问题。假设保险公司面临的赔付过程由带漂移的布朗运动描述。保险公司可以向再保险公司购买比例再保险,两公司均可以投资于一种无风险资产和一种价格过程服从Heston模型的风险资产,并以加权终端财富的期望效用最大化为目标,利用动态规划原理建立相应的HJB方程并求解,分别得到了保险公司与再保险公司的均衡投资与再保险策略的解析表达,并利用均衡保险市场上再保险合同的供需关系分析了保险产品的定价问题。最后通过数值实例分析了各模型参数对均衡策略的影响。     

不对称双寡头企业技术创新投资决策研究

许多研究技术创新投资决策的期权博弈文献忽视了企业之间的投资成本和经营成本的不对称性,本文研究成本不对称双寡头企业技术创新投资决策问题。首先,导出企业投资收益函数和投资临界值。接着对存在的三种均衡,即抢占均衡、序列均衡和同时投资均衡进行了分析讨论,结果表明,成本不对称程度较小和先动优势不大情况下,企业将同时投资;当先动优势较大的情况下,低成本企业将先投资成为领先者;当企业成本不对称程度很大时,企业将序列执行投资期权。最后,结合案例进行数值计算,验证了理论分析结果。     

网络外部性下不对称企业技术创新投资决策研究

许多研究技术创新投资决策期权博弈的文献大都假定企业是同质的和企业创新产品之间具有负的外部性,本文研究正网络外部性条件下成本不对称企业技术创新投资决策问题.首先,导出企业投资收益函数和投资临界值,接着对存在的2种均衡,即序列均衡和同时投资均衡进行分析讨论,结果表明,均衡的结果依赖于成本不对称程度和网络外部性的共同作用.最后,结合案例进行数值计算,验证了理论分析结果.     

考虑广告主投资竞争的关键词拍卖研究

关键词拍卖是搜索引擎盈利手段之一，同时给广告主带来高额回报。在搜索引擎注重质量权重的拍卖规则的推动下和广告主自身利益的驱使下，广告主通过投资来提高自身表现水平，赢得更好排位增加点击量。引入广告主投资，并用连续可变的努力水平来表征参与竞价的广告主投资过程中所付出的各种要素和资源投入，考虑投资和竞价两阶段模型，分析高低两类广告主的努力水平决策及均衡竞价策略。研究表明当满足初始投入最低努力水平时的边际成本大于边际收益的条件时，决定低类型广告主类型转换的估价阈值存在且唯一，并且在情形一中，潜力广告主的最优努力水平总是大于高类型广告主，在情形二中，随着估价的增大，两类广告主的最优努力水平趋于一致；同时，搜索引擎拍卖规则会影响广告主投资过程中最优努力水平的决策：搜索引擎给低类型广告主的质量权重越大，转换类型的估价阈值就越高，且潜力广告主取内点解时的最优努力水平和高类型广告主的最优努力水平均随之减少。最后，通过数值算例分析了两类广告主最优努力水平以及拍卖规则对广告主努力水平的影响。     

一般均衡理论视角下绿色金融的减排效应研究：从模型构建到实证检验

绿色金融是否能够有效促进碳减排？其内在机制是什么？在碳达峰与碳中和的时代目标下,科学、严谨地回答这一问题意义重大。本文将经典理论与最新前沿相结合,提出绿色金融能够通过促进绿色技术进步帮助碳减排的理论假说。构建带有碳排放约束并内生减排技术进步的一般均衡模型,解释了绿色金融通过支持技术进步实现碳减排的内在机制,并提供了基于中国省级面板数据的实证证据。本文的研究从理论和实证两个维度论证了绿色金融对碳减排的影响,指出支持技术创新是绿色金融发挥减排效应的重要机制。因而在发展绿色金融的过程中,注重金融资源的实际用途,有效支持减排技术更新,比单纯限制高排放行业的金融资源获取更加有效。同时,理论分析表明,绿色金融并非越多越好,而是存在最优规模。在积极推动绿色金融发展的同时,依然需要注重统筹规划,避免金融“过绿”带来不必要的损失。     

Aggregation and Optimization with State‐Dependent Pricing: A Comment

A key argument in Caplin and Leahy (1997) states that the correlation between monetary shocks and output is falling in the variance of the money supply. We demonstrate that this conclusion depends on solving for the correlation in the nonstationary state of the model. In the stationary state, that correlation is initially rising.     

Solving,Estimating, and Selecting Nonlinear Dynamic Models Without the Curse of Dimensionality

We present a comprehensive framework for Bayesian estimation of structural nonlinear dynamic economic models on sparse grids to overcome the curse of dimensionality for approximations. We apply sparse grids to a global polynomial approximation of the model solution, to the quadrature of integrals arising as rational expectations, and to three new nonlinear state space filters which speed up the sequential importance resampling particle filter. The posterior of the structural parameters is estimated by a new Metropolis–Hastings algorithm with mixing parallel sequences. The parallel extension improves the global maximization property of the algorithm, simplifies the parameterization for an appropriate acceptance ratio, and allows a simple implementation of the estimation on parallel computers. Finally, we provide all algorithms in the open source software JBendge for the solution and estimation of a general class of models.     

外商直接投资与我国三次产业技术进步相关关系研究

近几年来,我国利用外商直接投资(FDI)一直是理论界学者和实际工作者关心和研究的热点问题。现有成果主要关注FDI对经济增长的推动作用,系统研究FDI与技术进步关系的成果相对较少。本文在更加精确测算三次产业技术进步序列的基础上,研究FDI与我国技术进步的相关关系,重点分析FDI对我国三次产业技术进步的影响程度及特点。     

考虑决策者期望的企业R&D项目投资路径演化博弈研究

企业在对R&D项目投资时的路径选择行为受到决策者期望的影响。本研究在分析R&D项目投资路径及其决策者期望的基础上,根据政治关联性将企业分为国有企业和民营企业,构建了考虑决策者期望的企业R&D项目投资路径演化博弈模型。研究表明：民营企业是否选择最优路径的策略影响着演化均衡;对民营企业来说,初始投资额差异对该类企业选择最优路径的概率的影响完全一致;乐观决策者的数量、群体规模、决策者期望差异和初始阶段的投资额差异对两类企业选择最优路径的概率的影响程度不同。影响国有企业和民营企业路径选择的主要因素是乐观决策者的数量、期望差异和初始阶段投资额差异。以上结论有助于企业和政府更好地进行管理策略实施。     

控股股东现金流权、控制权与企业资本配置决策研究

基于企业内部资本配置的理论阐释,以无风险资产和风险性资产的组合投资为研究对象,从控股股东无偿占用上市公司内部资金的角度构建企业价值期权模型,探析控股股东的现金流权、现金流权与控制权分离度对资本配置决策和企业价值的影响。研究结果表明,控股股东的现金流权与企业资本配置效率正相关,与企业价值正相关;现金流权与控制权分离度与企业资本的配置效率负相关,也与企业价值负相关;并且发现,由大股东侵占而产生的对风险性资产的非效率"挤占"是导致上市企业资本配置行为扭曲的一个重要动因。     

Harnessing the Theoretical Foundations of the Exponential and Beta‐Poisson Dose‐Response Models to Quantify Parameter Uncertainty Using Markov Chain Monte Carlo

Dose‐response models are the essential link between exposure assessment and computed risk values in quantitative microbial risk assessment, yet the uncertainty that is inherent to computed risks because the dose‐response model parameters are estimated using limited epidemiological data is rarely quantified. Second‐order risk characterization approaches incorporating uncertainty in dose‐response model parameters can provide more complete information to decisionmakers by separating variability and uncertainty to quantify the uncertainty in computed risks. Therefore, the objective of this work is to develop procedures to sample from posterior distributions describing uncertainty in the parameters of exponential and beta‐Poisson dose‐response models using Bayes's theorem and Markov Chain Monte Carlo (in OpenBUGS). The theoretical origins of the beta‐Poisson dose‐response model are used to identify a decomposed version of the model that enables Bayesian analysis without the need to evaluate Kummer confluent hypergeometric functions. Herein, it is also established that the beta distribution in the beta‐Poisson dose‐response model cannot address variation among individual pathogens, criteria to validate use of the conventional approximation to the beta‐Poisson model are proposed, and simple algorithms to evaluate actual beta‐Poisson probabilities of infection are investigated. The developed MCMC procedures are applied to analysis of a case study data set, and it is demonstrated that an important region of the posterior distribution of the beta‐Poisson dose‐response model parameters is attributable to the absence of low‐dose data. This region includes beta‐Poisson models for which the conventional approximation is especially invalid and in which many beta distributions have an extreme shape with questionable plausibility.     

固定分区下随机需求IRP问题最优策略及算法

随机需求库存-路径问题(stochastic demand inventory routing problem,SDIRP)是典型的NP难题,考虑随机需求环境下供应链中库存与配送问题的协调优化,是实施供应商管理库存策略的关键所在.文章的研究基于固定分区策略(fixed partition policy,FPP),在FPP下客户被分为若干个服务区域,在同一区域中的所有客户均被同时配送.根据分区策略对配送以及库存成本的影响提出了基于修正C-W节约算法的客户分区算法,证明了各区域的最优库存策略为(s,S)形式,分区内各客户的库存策略为order-up-to形式,进而设计了求解FPP下SDIRP最优策略的算法.最后,通过数值算例验证了该算法的有效性以及FPP的适用性.     

企业报酬机制与人力资本投资

由于企业与员工双方都以自己的收益最大化为目标函数,所以当企业采取对产出按比例分成的报酬机制时,会导致双边道德风险,从而使员工实际的人力资本投资力度和工作努力程度以及企业的实际相关投入力度都低于整个社会福利最大化时的力度.如果企业能够采取另外一种报酬机制,使员工拥有完全剩余索取权,就能够使企业与员工都选择社会福利最大化时人力资本投资力度和工作努力程度以及相关投入力度.     

股票流动性、股价信息含量与企业投资决策

市场微观结构和公司财务学的交叉研究是当前的研究热点,以2001年～2007年仅发行A股的非金融类上市公司平衡面板数据为样本,采用高频数据构造相对有效价差和相对报价价差衡量股票流动性,考察股票流动性、股价信息含量与公司投资决策之间的关系。研究结果表明,股票流动性与股价信息含量呈倒U型关系,但是股票信息含量的大小并没有影响到投资和股价之间的敏感性,说明市场上的投资者可能更多的是挖掘管理者已有但没有披露出来的私有信息,而不是管理者没有的私有信息,因而管理者并不需要据此进行投资决策。此外,股票流动性与企业投资水平正相关,意味着股票流动性通过扩展企业的投资机会集而影响企业的投资行为。使用不同的代理变量进行稳健性检验均没有改变研究结论。     

主要排放部门的减排责任分担研究:基于全局成本有效的分析

运用中国能源与环境政策分析模型(CEEPA),从经济全局成本有效的角度,分析了一定减排约束下中国主要排放部门宜分担的减排责任及其减排行为。研究发现,基于排放量进行减排责任部门分担是有助于整体成本的,但对煤炭和运输仓储部门宜做出调整;随着减排目标的增加,应增添运输仓储部门的减排配额比例,减少煤炭部门的减排配额比例;短期内不宜对各部门尤其是煤炭部门设置较高的减排目标。     

公路建设项目的模糊排序和投资决策优化

本文论述了公路建设项目排序的评判指标,在运用模糊贴近度原理,分析确定各待建项目建设迫切性的基础上,采用整体投资决策优化模型,对公路网规划方案中建设项目的序列安排问题进行了探讨,收到了较好的效果．     

Inventory Models with Continuous and Poisson Demands and Discounted and Average Costs

We develop a new, unified approach to treating continuous‐time stochastic inventory problems with both the average and discounted cost criteria. The approach involves the development of an adjusted discounted cycle cost formula, which has an appealing intuitive interpretation. We show for the first time that an (s, S) policy is optimal in the case of demand having a compound Poisson component as well as a constant rate component. Our demand structure simultaneously generalizes the classical EOQ model and the inventory models with Poisson demand, and we indicate the reasons why this task has been a difficult one. We do not require the surplus cost function to be convex or quasi‐convex as has been assumed in the literature. Finally, we show that the optimal s is unique, but we do not know if optimal S is unique.     

我国35个大中城市人力资本投资实证分析

城市是人力资本的重要集散地,是人力资本投资的主要场所。本文构建了城市人力资本投资指标体系,运用主成分分析方法对我国35个大中城市人力资本投资进行了比较分析,并给出各城市得分及排序。     

Application of a QMRA Framework to Inform Selection of Drinking Water Interventions in the Developing Context

The aim of this study was to develop a modified quantitative microbial risk assessment (QMRA) framework that could be applied as a decision support tool to choose between alternative drinking water interventions in the developing context. The impact of different household water treatment (HWT) interventions on the overall incidence of diarrheal disease and disability adjusted life years (DALYs) was estimated, without relying on source water pathogen concentration as the starting point for the analysis. A framework was developed and a software tool constructed and then implemented for an illustrative case study for Nepal based on published scientific data. Coagulation combined with free chlorine disinfection provided the greatest estimated health gains in the short term; however, when long‐term compliance was incorporated into the calculations, the preferred intervention was porous ceramic filtration. The model demonstrates how the QMRA framework can be used to integrate evidence from different studies to inform management decisions, and in particular to prioritize the next best intervention with respect to estimated reduction in diarrheal incidence. This study only considered HWT interventions; it is recognized that a systematic consideration of sanitation, recreation, and drinking water pathways is important for effective management of waterborne transmission of pathogens, and the approach could be expanded to consider the broader water‐related context.