风险投资联合投资对上市公司盈余管理的影响:基于我国创业板的实证研究

风险投资在中国的经济发展中处于越来越重要的位置,创业板355家上市公司中,近60%的公司有风险投资背景,近40%的公司有联合风投背景.本文首先以2009-2012年创业板355家上市公司为研究对象,实证研究了风险投资个数与盈余管理之间的关系,然后,以132家联合风投背景公司为研究对象,实证研究联合风投内部特征对IPO公司盈余管理的影响,试图探讨能够发挥最佳监督作用的联合投资方式.实证结果显示有风投背景公司的盈余管理程度高于无风投背景的公司,且联合风投个数越多,上市公司盈余管理程度越高.尽管如此,可以通过选择适当的联合投资方式降低联合投资的负面效应,比如:提高联合风投多样化程度、提高主导风投持股比例、选择高声誉主导风投等等.     

考虑声誉效应的众包竞赛动态激励机制研究

将声誉效应引入众包竞赛的激励机制可以促使接包方为考虑未来绩效收益而提高当前努力。建立并求解了显性和隐性声誉效应下连续两个任务阶段的动态激励模型,探讨了显性声誉修正系数、隐性声誉系数以及参赛者数量对激励效果的影响,并与无声誉激励机制进行了对比。研究表明,声誉激励机制通过单位绩效激励强度和固定奖励水平两条途径起作用,增大隐性声誉系数有助于提高每个任务阶段的努力程度,显性声誉不确定性则会降低第2任务阶段的努力程度;各种条件下实施声誉激励对第1任务阶段中的努力程度和单位绩效奖励的影响存在不确定性;参赛者数量的增加有助于弱化第1任务阶段中棘轮效应,但也会降低声誉激励机制对努力程度的正向价值,扩大声誉激励机制对单位绩效奖励的负向价值。     

金融风险在股票市场的传染效应及联动行为分析

近年来金融危机频发并表现出了易传染性,引起了众多学者的高度关注。以动态条件相关模型研究美欧股市与中、日、韩股市间的时变相关性,并结合内生多重结构突变模型划分危机传染阶段,选用溢出指数模型分析股市间的风险溢出特性;随后,定义股市间相互影响的联动模式并构建不同传染阶段的加权有向网络图分析股市间的联动行为。研究表明:美欧股市对中日韩股市有明显的传染效应,被传染的速度和持续时间均不相同;金融传染和风险溢出展现出一定的不一致性,危机期间日股的风险溢出效应强于美股;传染效应在联动网络中表现为联动模式的高聚类性和高联动性,相比欧债危机,次贷危机时期股市间展现出更强的联动行为;日股与美欧股市在两次危机中均表现出最强的联动性,其所受影响也最大。     

税收优惠、研发投入与企业绩效——基于中介效应的实证研究

基于"税收优惠-行为-经济后果"的研究范式,利用2012-2016年191家高新技术企业上市公司的面板数据,以研发投入为中介变量,研究税收优惠对企业绩效的影响关系,并探索研发投入的中介效应.实证结果显示:税收优惠对企业绩效和研发投入均产生显著正向影响;企业研发投入在税收优惠与企业绩效之间具有部分中介效应.因此,高新技术企业应当有效利用税收优惠政策,增大研发力度以提升绩效水平.     

自主研发与技术引进对企业绩效影响差异分析

以上海工业企业为研究样本分析了企业自主研发和技术引进对企业绩效的不同贡献.文中将两种不同的促进技术进步策略作异质性的分析处理,同时考虑模型的选择偏差,再通过计量方法的匹配,做基于倾向得分的平均处理效应估计.研究结果显示,同不做任何技术创新与引进的企业相比,试图通过技术进步寻求发展的企业均对企业绩效产生了积极效应.其中技术引进方式对企业的当期利润和企业劳动生产率的提高更优于自主研发方式,而自主研发对于企业TFP的贡献却是大于技术引进的.研究还显示这两种技术进步方式对于不同所有制结构的企业作用不同.     

技术创新、溢出效应与最优环境政策组合

构建环境政策内生的三阶段博弈模型,分析存在技术溢出效应时,环境政策组合工具对企业绿色技术创新的影响。研究发现,排污税和研发补贴有利于企业进行绿色技术创新,两者组合可以实现社会福利最大化。社会最优排污税税率低于排污对社会的边际破坏程度,并随着均衡产量的增加而提高。在技术溢出效应较高时,政府采取排污税和补贴的组合工具,而当技术溢出效应较低时,政府采取排污税和研发税的组合工具。当排污税税率外生给定时,竞争创新情况下的政府补贴要高于协同创新情况下的政府补贴。政府应结合行业技术溢出特征,采取相应的税收与补贴结合的政策工具,并在知识产权保护的基础上,促进企业集群协同绿色技术创新。     

竞争性企业技术联盟的知识共享效应研究

通过三阶段博弈模型分析竞争性企业技术联盟知识共享效应,结果表明:知识共享的程度是随着竞争性企业技术联盟规模的扩大而增加的.因为随着技术联盟规模的扩大,知识共享的规模收益会逐渐上升,从而减少了由于知识溢出而带来的损失.因此,在企业技术联盟内部构建一个能够有效地吸收、保持和共享知识的机制对于提高技术联盟的绩效具有积极的作用.     

牛鞭效应弱化与反牛鞭效应强化在完美信息下联合作用的博弈

在供应链运作过程中,同时存在牛鞭效应与反牛鞭效,若仅考虑到供应链的成本、需求偏差等问题,这种存在会因有限理性的驱使使得牛鞭效应弱化与反牛鞭效应强化.因此,认为供应链的上下游在周期内会表现出牛鞭效应弱化与反牛鞭效应强化的联合作用,联合作用使得单个企业达到低平均库存成本,也意味着供应链的整体库存最低且整体市场需求偏差最低,间接地、自动地从整体上消除牛鞭效应或反牛鞭效应,使得整条供应链不管是短期的还是长期来看是最佳的,若是长期,还会给供应链企业带来显著的战略优势.     

第三方物流整合对绩效影响:企业特征的调节效应的实证研究

本文研究第三方物流整合对企业绩效的影响以及企业特征的权变效应,通过对130家物流外包企业的问卷调查数据的实证分析发现第三方物流整合促进企业绩效提高,并且这种促进作用受到企业特征(企业规模、年龄、所有制结构、行业)的影响。企业规模越大,第三方物流整合对运营绩效的促进作用越明显;企业年龄越大,第三方物流整合对财务绩效的影响越小;本土企业实现第三方物流整合对绩效的促进作用要明显优于外资企业;服务业企业实现第三方物流整合对绩效的促进效果比制造业更强。     

中国政府公共支出在GDP长期增长中替代效应及互补效应的实证研究

本文通过对财政变量的替代效应及互补效应的分析,系统地研究了中国政府特殊公共支出体系各组成部分与GDP之间的长期动态关系,并利用方差分解技术具体分离了政府公共支出各组成部分对GDP的增长效应。通过实证研究我们认为,政府购买支出表现出一定的互补性、对经济的长期增长有一定的解释能力,而预算外支出、政府基础设施投资则表现出一定的替代性,对经济的长期增长解释能力十分有限。     

Rivalry and uncertainty in complementary investments with dynamic market sharing

We study the effects of revenue and investment cost uncertainty, as well non-preemption duopoly competition, on the timing of investments in two complementary inputs, where either spillover-knowledge is allowed or proprietary-knowledge holds. We find that the ex-ante and ex-post revenue market shares play a very important role in firms’ behavior. When competition is considered, the leader’s behavior departs from that of the monopolist firm of Smith (Ind Corp Change 14:639–650, 2005). The leader is justified in following the conventional wisdom (i.e., synchronous investments are more likely), whereas, the follower’s behavior departs from that of the conventional wisdom (i.e., asynchronous investments are more likely).     

Quantitative portfolio selection: Using density forecasting to find consistent portfolios

In the knowledge that the ex-post performance of Markowitz efficient portfolios is inferior to that implied ex-ante, we make two contributions to the portfolio selection literature. Firstly, we propose a methodology to identify the region of risk-expected return space where ex-post performance matches ex-ante estimates. Secondly, we extend ex-post efficient set mathematics to overcome the biases in the estimation of the ex-ante efficient frontier. A density forecasting approach is used to measure the accuracy of ex-ante estimates using the Berkowitz statistic, we develop this statistic to increase its sensitivity to changes in the data generating process. The area of risk-expected return space where the density forecasts are accurate, where ex-post performance matches ex-ante estimates, is termed the consistency region. Under the 'laboratory' conditions of a simulated multivariate normal data set, we compute the consistency region and the estimated ex-post frontier. Over different sample sizes used for estimation, the behaviour of the consistency region is shown to be both intuitively reasonable and to enclose the estimated ex-post frontier. Using actual data from the constituents of the US Dow Jones 30 index, we show that the size of the consistency region is time dependent and, in volatile conditions, may disappear. Using our development of the Berkowitz statistic, we demonstrate the superior performance of an investment strategy based on consistent rather than efficient portfolios.     

Price competition in the Hotelling model with uncertainty on costs

For the linear Hotelling model with firms located at the boundaries of the segment line, we study the price competition in a scenario of incomplete information in the production costs of both firms. We introduce the bounded uncertain costs (BUC) condition in the production costs and we prove that there is a local optimum price strategy if and only if the BUC condition holds. We compute explicitly the local optimum price strategy and we prove that it does not depend upon the distributions of the production costs of the firms, except on their first moments. We prove that the ex-post profit of a firm is smaller than its ex-ante profit if and only if the production cost of the other firm is greater than its expected cost.     

管理者过度自信对高技术企业技术外部获取方式选择的影响研究

企业管理者的业绩预测偏差是衡量管理者是否过度自信的一个重要体现,值得关注和研究。本研究采用我国2004~2013年高技术上市公司的相关数据,应用Ordered-probit模型实证分析了管理者过度自信对高技术上市公司技术外部获取方式选择的影响。研究结果表明:我国高技术上市公司以非股权技术联盟作为首要的技术外部获取方式,公司风险投资是最后的选择;同时,研究发现:在对技术外部获取方式进行选择时,管理者过度自信的高技术上市公司选择并购优先于合资和少数持股联盟,而管理者非过度自信的高技术上市公司选择少数持股联盟优先于并购和合资。该研究方法简单、高效、合理,是企业高管提升公司管理水平和科学获取技术外部的一种新的方法选择。     

Flexibility in a Stackelberg leadership with differentiated goods

We study the effects of product differentiation in a Stackelberg model with demand uncertainty for the first mover. We do an ex-ante and ex-post analysis of the profits of the leader and of the follower firms in terms of product differentiation and of the demand uncertainty. We show that even with small uncertainty about the demand, the follower firm can achieve greater profits than the leader, if their products are sufficiently differentiated. We also compute the probability of the second firm having higher profit than the leading firm, subsequently showing the advantages and disadvantages of being either the leader or the follower firm.     

Simulation and evaluation of the distribution of interest rate risk

We study methods to simulate term structures in order to measure interest rate risk more accurately. We use principal component analysis of term structure innovations to identify risk factors and we model their univariate distribution using GARCH-models with Student’s t-distributions in order to handle heteroscedasticity and fat tails. We find that the Student’s t-copula is most suitable to model co-dependence of these univariate risk factors. We aim to develop a model that provides low ex-ante risk measures, while having accurate representations of the ex-post realized risk. By utilizing a more accurate term structure estimation method, our proposed model is less sensitive to measurement noise compared to traditional models. We perform an out-of-sample test for the U.S. market between 2002 and 2017 by valuing a portfolio consisting of interest rate derivatives. We find that ex-ante Value at Risk measurements can be substantially reduced for all confidence levels above 95%, compared to the traditional models. We find that that the realized portfolio tail losses accurately conform to the ex-ante measurement for daily returns, while traditional methods overestimate, or in some cases even underestimate the risk ex-post. Due to noise inherent in the term structure measurements, we find that all models overestimate the risk for 10-day and quarterly returns, but that our proposed model provides the by far lowest Value at Risk measures.

     

Estimation risk and stability of optimal portfolio composition

The mean-variance portfolio models indicate that for optimal investment decisions, the ‘true’ ex-ante values of the model parameters should be used. Instead, in practice, ex-post parameter estimates are used. If in the estimation process, the probability distribution of estimators is not known, there is a problem of estimation risk. This paper investigates the impact of estimation risk on the composition of optimal portfolios. As the multivariance distribution of the vector of optimal portfolio weights allocated to risky assets is analytically intractable, a use of the Monte Carlo simulation experimental is made. This study suggests that the composition of optimal portfolio is relatively more stable when the estimates of model parameters are obtained from longer series of historical observations or the expected portfolio return is low.     

Selection of entrepreneurs in the venture capital industry: An asymptotic analysis

We study a model of entrepreneurs who compete in an auction-like setting for venture capital (VC) funding in a setting where limited capital dictates that the VC can only finance the best entrepreneurs. With asymmetric information, VCs can only assess entrepreneurs by the progress of development, which, in equilibrium, reveals the quality of the new technology. Using an asymptotic analysis, we prove that in attractive industries having a large number of entrepreneurs competing for VC funding could lead to underinvestment in technology by entrepreneurs as the effort exerted by losing entrepreneurs is wasted. The study then proceeds to characterize the conditions under which a greater number of competing entrepreneurs is better. The model also demonstrates that VCs could possibly increase their payoff by concentrating on a single industry. In addition, the study also provides some insights on the effects of multiple investments by VCs and the effects of competition among VCs on the same investments.     

环境规制对出口产品质量的影响研究——基于行业面板数据的实证分析

本文以环境规制作为解释变量,基于2003~2010年中国19个行业出口产品质量和环境规制数据,采用固定效用模型实证检验了环境规制对出口产品质量的影响。研究结果表明,环境规制对出口产品质量的影响呈“U”型,即环境规制增强前期成本效应大于创新效应,经营成本提高导致产品质量下降;环境规制增强后期创新效应大于成本效应,研发创新促使产品质量提高。不同行业对环境规制的敏感度不一样,将样本数据中涉及的19个部门,分为重污染行业和轻污染行业进行分类回归,回归结果显示环境规制对轻度污染行业出口产品质量的影响呈倒“U”型,即具有先促进后抑制的作用;环境规制对重度污染行业出口产品质量的影响呈“U”型,即具有先抑制后促进的作用。据此,提出有效利用环境规制以提高出口产品质量和发展绿色贸易的政策启示。