Euro area sovereign yield spreads as determinants of private sector borrowing costs

We regress long-term private-sector borrowing rates on a money market rate, a term premium and credit risk. As a contribution to the current debate about European safe assets, our interest is in quantifying the impact of euro area sovereign bond spreads on private-sector lending by employing it as a proxy for private-sector credit risk. Panel estimates show significant, albeit rather small long-run effects. Another finding is large cross-country heterogeneity. Using linear country-specific estimates, we find the effect to be significant in only some countries, but the size of the maximum effect in these countries exceeds the average one more than three-fold. Furthermore, for one country, we find an asymmetrical effect with positive spread changes having greater impact on private-sector borrowing costs than negative ones. Substantial heterogeneity of the spillover effect between euro area countries indicates the presence of financial valuation effects based not only on economic fundamentals. This, in turn, implies that spillovers may entail contagion costs. Overall, our results suggest that these costs are considerable in the euro area and will remain so until an effective form of European safe assets is created.     

Trading volume and stock returns: A meta-analysis

I examine 468 estimates on the relationship between trading volume and stock returns reported in 44 studies. I study publication bias together with Bayesian and frequentist model averaging to explain the heterogeneity in the estimates. The results yield three key conclusions. First, publication bias distorts the findings of the primary studies. Second, the predictability of stock returns varies with different markets and stock types. Third, different data characteristics, structural variations and methodologies used drive the heterogeneity in the results of the primary articles. In particular, one should be cautious when using monthly data or VAR models.     

Optimal model averaging forecasting in high-dimensional survival analysis

This article considers ultrahigh-dimensional forecasting problems with survival response variables. We propose a two-step model averaging procedure for improving the forecasting accuracy of the true conditional mean of a survival response variable. The first step is to construct a class of candidate models, each with low-dimensional covariates. For this, a feature screening procedure is developed to separate the active and inactive predictors through a marginal Buckley–James index, and to group covariates with a similar index size together to form regression models with survival response variables. The proposed screening method can select active predictors under covariate-dependent censoring, and enjoys sure screening consistency under mild regularity conditions. The second step is to find the optimal model weights for averaging by adapting a delete-one cross-validation criterion, without the standard constraint that the weights sum to one. The theoretical results show that the delete-one cross-validation criterion achieves the lowest possible forecasting loss asymptotically. Numerical studies demonstrate the superior performance of the proposed variable screening and model averaging procedures over existing methods.     

金融资源配置、技术进步与经济高质量发展

随着我国发展阶段及内外部条件的变化,科技创新已成为新时代引领我国经济高质量发展的核心驱动力。本文以金融驱动技术进步的视角,构建内生增长DSGE模型,分析金融资源配置、技术进步和经济增长之间的关系。研究佐证了我国技术创新的逆周期性,并发现金融资源在企业生产性投资与创新投资之间的分配,可以通过改变生产要素投入规模和技术进步率两种途径影响经济增长,且这两种影响之间存在“跷跷板”关系,但后者更具主导性。在此基础上,诠释了金融、技术与经济的动态传导机制:经济扩张期,企业生产规模扩张,金融资源对生产性投资的支持增加,对创新的投入相对减少,技术进步率放缓;经济收缩期,企业缩减生产规模,金融资源对生产性投资的支持减少,对创新的投入相对增加,技术进步率提升。本研究的政策启示为,面对当前发展新矛盾、新挑战,应把握发展新格局、新机遇,进一步深化金融改革,优化金融资源配置机制,鼓励创新投资,充分发挥股权市场对企业研发创新的支持作用,并辅以稳健适度的宏观调控政策,为企业创新提供良性的宏观环境,激活企业创新需求,促进技术进步,推动经济高质量发展。     

Exploring the development trend of internet finance in China: Perspective from club convergence

We first employ β-conditional convergence and log t regression tests based on nonlinear time-varying factor model and club clustering algorithm to analyze the convergence characteristics of the development level of Internet finance in 335 prefecture-level cities in China. The result of log t regression test illustrates that there is no convergence as a whole in the development level of China's Internet finance. However, seven convergence clubs and a divergent group have been formed, and the development level and growth rate of Internet finance among these convergence clubs have shown obvious differences. Moreover, we also employ the Ordered Probit to explore the formation mechanism of the convergence clubs. The results reveal that the regions with a higher level of economic development, traditional financial development, economic openness and Internet development are more inclined to converge in a club with a higher Internet finance development level. Alternatively, the regions that are interfered with more by the government or that have a lower degree of marketization, tend to converge in a club with a lower level. Finally, according to the conclusions, we propose corresponding policy recommendations for promoting the regional coordinated development of China's Internet finance.     

预期寿命、生育率变动与基本养老保险统筹账户调整

在构建三期世代交叠模型的基础上，通过选取相关制度指标来模拟分析在未来预期寿命和生育率变动下，基本养老保险统筹账户如何基于参数调整来维持收支平衡。研究结果表明：（1）我国居民预期寿命增长过快，统筹账户收支平衡受预期寿命变化影响较大；（2）在现阶段的预期寿命和生育率条件下，统筹账户能实现自身收支平衡，而且可在短期内通过阶段性降低缴费率来促进制度长远发展；（3）在长期内需通过提高缴费率或降低养老金替代率来保证统筹账户收支平衡，预期寿命为87.828岁且总和生育率为1.79作为参数调整临界点；（4）以现有制度设计为基准，参数调整临界点之前保证35%的基础养老金平均替代率不降，临界点之后保证20%的缴费率不升可以最大程度促进经济和社会发展。     

城市轨道交通相邻多车站动态协同限流研究

为应对城市轨道交通车站高峰期客流压力,限流已经成为常态应对措施,而经常采用的限流策略大多针对单个车站,缺少对相邻多个车站的协同考虑。基于客流在车站间的传播效应,以乘客总延误时间最小为目标,以站台及列车能力为约束条件,构建城市轨道交通相邻多车站协同限流决策模型,同时为实现实时动态控制,引入滚动时域控制方法,优化多车站动态协同限流流程。以北京地铁8号线为例,经过相邻若干车站运营数据进行限流策略计算。结果表明,该模型限流可以在不造成车站服务人数损失的同时,将乘客总延误时间降低21%。     

创新要素流动对城市群协同创新的影响——基于长三角城市群与长江中游城市群的实证

利用2006-2017年长三角城市群和长江中游城市群共41个地级市面板数据，首先，运用拓展DEA法对两大城市群协同创新水平进行测度，然后，采用空间计量模型实证考察创新要素流动对城市群协同创新的影响，进一步以互联网发展水平为门限变量，构建门限模型，探析互联网发展对创新要素在城市群流动的协同创新效应是否存在门限效应。研究发现：创新要素流动对城市群协同创新影响的总效应显著为正，空间正向溢出效应显著，且存在群际差异；在两大城市群内，创新要素流动对城市群协同创新影响呈现非线性，创新人员流动对城市群协同创新影响呈“倒U型”特征，创新资本流动对城市群协同创新影响呈“U型”关系，相应拐点在不同城市群呈现异质性。     

上市促进了企业创新吗?——来自创业板制造业企业的经验证据

本研究利用手工收集的2009-2013年在创业板市场申请上市的制造业企业样本以及企业创新专利变量,经过对成功上市企业与终止上市企业的样本匹配,运用双重差分模型考察了上市是否促进我国创业板制造业企业创新,研究结果表明,上市显著促进了企业专利创新。进一步地,我们探讨了上市促进企业创新的机制,结果发现,上市通过改善融资约束显著促进了企业创新,而上市没能通过影响代理问题作用于企业创新。该结果意味着直接金融发展有助于推动企业创新;资本市场的风险分担及融资机制能够降低企业融资约束、进而促进企业创新。这不仅为直接金融促进企业创新提供了新的证据,也为我国进一步发展与完善资本市场,进而促进经济转型、创新发展提供了新的政策启示。     

国有企业的扩张行为:动机及效应

文章通过建立国企的效用最大化的目标函数,揭示其包含了来自市场激励和政府激励的多元化目标,其中规模最大化是效用最大化的最近似的可量化目标,其能够包括并同时满足国企追求的其它效用目标。本文表明了国企持续超常的规模扩张是建立在长期高额负债率和利润率显著低下的基础上,证实了国企不仅缺乏融资约束,也缺乏市场竞争约束。由于这两个基本约束的软化,导致企业过度膨胀,超过了正常合理水平。由于规模庞大且层级结构复杂,还会加剧了企业的难以监控的"黑箱"行为。这种机制可能诱发腐败,还导致一系列不良效应,包括产能过剩,僵尸企业,垄断势力强化,企业成本剧增等等。对于市场约束的缺位,合理的解决路径是加强市场约束,而不是加强行政约束。改革的选择方向是,实行分类改革,对于面向市场的企业,需要在利益相关者之间通过合理契约来实现市场激励和约束。