研发市场界定的适用困境及应对策略

研发市场是经营者在特定产品和技术竞争中形成的市场范围。由于研发活动的不确定性，反垄断执法机关在界定研发市场时难以准确厘定市场边界，更深层次的原因在于维持竞争与激励研发的关系尚不明晰。研发竞争中的垄断行为难以通过相关市场界定的方式判断其违法性，需要结合具体案情和市场条件，动态分析涉案行为是否损害产品或技术研发竞争。     

Nowcasting China’s GDP Using a Bayesian Approach

Real time nowcasting is an assessment of current-quarter GDP from timely released economic and financial series before the GDP figure is disseminated. Providing a reliable current quarter nowcast in real time based on the most recently released economic and financial monthly data is crucial for central banks to make policy decisions and longer-term forecasting exercises. In this study, we use dynamic factor models to bridge monthly information with quarterly GDP and achieve reduction in the dimensionality of the monthly data. We develop a Bayesian approach to provide a way to deal with the unbalanced features of the dataset and to estimate latent common factors. We demonstrate the validity of our approach through simulation studies, and explore the applicability of our approach through an empirical study in nowcasting the China’s GDP using 117 monthly data series of several categories in the Chinese market. The simulation studies and empirical study indicate that our Bayesian approach may be a viable option for nowcasting the China’s GDP.     

TrAffic LIght system for systemic Stress: TALIS3

For the purposes of financial stability, identifying financial institutions that, when in distress, could have a significant adverse impact on financial markets is important. A TrAffic LIght System for Systemic Stress (TALIS-cube) is proposed that provides a comprehensive color-based classification for grouping companies according to both the stress reaction level of the system when the company is in distress and the company’s stress level. TALIS³ can integrate multiple signals from the interaction between different risk metrics. Starting from specific risk indicators, companies are classified by combining two loss functions—one for the system and one for each company—evaluated over time and as a cross section. An aggregated index is also obtained from the color-based classification of companies. TALIS³ can be used to enhance the performance and robustness of existing systemic risk measures. An empirical analysis of the U.S. market is also provided.     

Public and private healthcare services: What drives the choice?

This paper has explored patients' propensity to consume private healthcare services. We based our analysis on the typical tangible and intangible (for instance, responsiveness, reliability, assurance and staff empathy) domains of the SERVQUAL and SERVPERF methods. These variables may influence patients' decision-making when they choose between the public and private sectors. We combined factor analysis (to obtain a set of latent factors related to perceived quality) and a partial proportional ordered logit model to estimate the probability that a patient would access private healthcare services. To test the main hypotheses, we used data from a stratified sample in Sardinia, a peripheral region of Italy. Findings revealed that private and public healthcare are substitutes, especially for primary/specialised services. Patients who used public healthcare frequently and had a low income were unlikely to change to private healthcare or to recommend private services. ‘Responsiveness’ and perceptions on ‘tangibles’ were key in determining the probability that a patient would choose and recommend private services. This paper offers a multifaceted framework that can be used in future research to generalise these findings, especially in insular regions that are constrained by mobility.     

Relationship between city size and firm productivity – A new interpretation using the Chinese experience

This paper contributes to the literature on the relationship between city size and firm productivity by focusing on agglomeration, selection (market competition), and sorting (presence of firms with diverse productivity) effects using Chinese firm-level data for 1998–2013. Contrary to the existing literature, our parametric regression estimates from nearly two million firms show that when the selection effect is controlled, productivity advantage in big cities is reversed. This outcome is explained through a quantile regression showing the existence of left-sided sorting (inefficient firms sort themselves to larger cities) in big cities which is not captured in existing empirical literature. We further find that (1) left-sided sorting is stronger in exporters than non-exporters; (2) is also generated mainly in enterprises with high asset-liability ratios; and (3) selection has a positive effect on firm productivity, suggesting that market competition is key in an explanation of the rapid growth of big cities in China.     

Factor state–space models for high-dimensional realized covariance matrices of asset returns

We propose a dynamic factor state–space model for high-dimensional covariance matrices of asset returns. It makes use of observed risk factors and assumes that the latent integrated joint covariance matrix of the assets and the factors is observed through their realized covariance matrix with a Wishart measurement density. For the latent integrated covariance matrix of the assets we impose a strict factor structure allowing for dynamic variation in the covariance matrices of the factors and the residual components as well as in the factor loadings. This factor structure translates into a factorization of the Wishart measurement density which facilitates statistical inference based on simple Bayesian MCMC procedures making the approach scalable w.r.t. the number of assets. An empirical application to realized covariance matrices for 60 NYSE traded stocks using the Fama–French factors and sector-specific factors represented by Exchange Traded Funds (ETFs) shows that the model performs very well in- and out of sample.     

1864例药物不良反应报告分析

目的了解某院药品不良反应(ADR)的发生特点及规律,为临床安全用药提供参考。方法对合肥市第二人民医院2016年至2018年上报的ADR报告进行回顾性分析。结果1864例ADR中,66~89岁患者所占比例最高(768例,占41.20%);女性患者984例,略多于男性(880例);静脉给药引发的ADR最多,占81.33%;发生ADR的药品主要为抗菌药品,其次为抗肿瘤药和中药制剂;ADR主要累及消化系统、皮肤及附件;ADR类型主要为一般ADR,导致严重的ADR主要是抗肿瘤药;ADR转归情况以痊愈和好转为主,两者占94.31%。结论老年患者更易发生ADR;抗菌药、抗肿瘤药等ADR发生率较高;所有剂型中注射剂型ADR发生率最高;消化系统、皮肤及附件损害最为常见。     

经济增长质量的研究进展与学术展望

改革开放40多年来，中国经济铸就了高速增长奇迹，目前已经具备向高质量发展转变的客观条件。本文通过梳理中国经济增长质量的相关文献，总结当下经济增长质量问题的研究不足和未来研究方向。研究发现：关于经济增长质量的文献集中在经济增长质量的内涵界定和解析、经济增长质量的评价维度与定量测度、经济增长质量的影响因素与调控政策等方面，研究成果较为丰富，但也存在经济增长质量的评价指标选取不一致、经济增长质量的评价指标缺乏宏微观维度区分、经济增长速度和增长质量关系认识不清等问题，今后学术研究当以此为重点突破方向。本文关于经济增长质量的文献梳理和评价，对各界理解经济高质量发展，确定经济增长质量的研究方向具有重要意义。     

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。     

数字经济对中国全要素生产率的影响机理:提升效应还是抑制效果？

数字经济是新时代引领中国经济高质量发展的关键抓手。然而现阶段数字经济普惠性发展尚未实现，掣肘着其对国内全要素生产率的提升力度。文章在理论分析的基础上，基于熵权TOPSIS法测算了2012-2018年中国数字经济发展水平指数，探讨了中国数字经济对全要素生产率的影响机理。研究发现：数字经济的发展显著提升了中国全要素生产率水平，但区域层面上，东部地区的数字经济发展明显领先于中西部地区，引领着中国全要素生产率快速增长。从全要素生产率的分解指标来看，数字经济推动了技术效率提升，但现阶段国内关键核心技术环节薄弱以及数字产业化带来的人才和资金的虹吸效应导致数字经济对技术进步产生了阻碍作用。此外，当前数字经济对不同产业的渗透度存在明显的不均衡性，筑高了创新资源的流动壁垒，影响产业间协调创新及合理化布局，进而抑制了对全要素生产率的提升力度。进一步的机制检验表明在创新环境的支持下，人才集聚及金融规模强化了数字经济对全要素生产率的提升力度。