城市化、城市集中度与人力资本积累――基于省级面板数据的实证研究

鉴于人力资本对经济增长的作用日显重要,人们希望知道哪些因素显著影响到人力资本,其中城市化水平、城市集中度等通过经济集聚强度而明显影响人力资本积累。城市化通过刺激人力资本供给与需求,创造良好的人力资本投资环境而促进人力资本积累,城市集中度提高带来的规模优势与外部不经济双重效应使其对人力资本积累具有两面性。依据2000—2015年我国30个省(直辖市、自治区)的面板数据,考虑省份之间的异质性及空间相依性,分别建立非线性面板模型和空间杜宾模型开展实证分析。结果表明：城市化水平与人力资本积累高度正相关,城市化对人力资本积累产生显著的促进效应;城市集中度与人力资本之间存在倒U型关系,不同地区城市集中度对人力资本的影响效应存在明显差异;城市化、城市集中度对人力资本的影响效应具有较强的稳健性。结论对于推动城市与区域经济高质量发展具有启示意义。     

Does aid for trade diversify the export structure of recipient countries?

The importance of aid for trade as a tool for facilitating trade, economic growth and social development has received attention since the concept was introduced in 2005. While one of the main targets of aid for trade is export diversification, reflecting the fact that the exports of many developing countries are concentrated in a small range of items, there have not been many efforts to measure the effect of aid for trade on export structure. This study, therefore, attempts to trace the relationship between aid for trade and 133 aid recipients' export structure between 1996 and 2013. Using the Herfindahl–Hirschman Index to measure the degree of export concentration, the findings suggest that total aid for trade has reduced the concentration level in the short run. In the long run, on the other hand, aid for trade has had no significant effect on export structure of recipient countries. Only aid for building productive capacity, which is one of the three categories of aid for trade, contributes to lower concentration. Yet, this change is not caused by an increase in export diversity but by the redistribution of shares of existing products of a similar sophistication level.     

City Size,Population Concentration and Productivity: Evidence from China

This paper investigates the impact of China's city size and urban population concentration on city productivity by developing a distinctive index based on global nighttime light data. Using the panel data of 280 prefecture cities from 2004 to 2013 and employing dynamic system generalized method of moments and panel threshold model regression techniques, our results show that city size has a positive impact on city productivity; therefore, cities in China still have the potential to expand. While moderate urban population concentration can benefit city productivity, excessively concentrated urban population distribution may impede the growth of city productivity. We also find that the level of labor income significantly affects the impacts of urban agglomeration on labor productivity. Therefore, our results imply that city development policies should focus more on how to appropriately allocate economic activities and adjust population distribution in urban areas according to different stages of economic development.     

Optimal privatization policy with asymmetry among private firms

We revisit the relationship between the optimal privatization policy and market competition indexes such as the Hirschman–Herfindahl index. It is affected by the number of the firms and asymmetry among the sizes of the firms; the smaller the number of firms and the more asymmetry among firms, the higher the market concentration index. The literature on mixed oligopolies suggested that the optimal degree of privatization increases with the number of private firms, and thus, decreases with the market competition index, assuming that all private firms are homogeneous. We investigate how asymmetry among private firms affects the optimal degree of privatization. We propose the simplest and natural model formulation to discuss asymmetry among private firms. We find that the optimal degree of privatization is either nonmonotone or monotonically increasing, and thus never monotonically decreasing, in asymmetry among private firms.     

医疗器械产业创新集群的现状及路径研究——以宁波市为例

产业集群能提高企业、区域和国家竞争力。当前以产业创新集群为代表的新一轮产业集群正在各地兴起。通过行业融合、知识外溢和集体行动，产业创新集群促进相关企业和支持性机构紧密互动而加速创新。医疗器械产业科技含量高，创新性强，是当前少数几个涉及学科最多的产业之一。以医疗器械产业为研究对象，从集群和区域创新发展的要义出发，挑选宁波地区的医疗器械行业，测算其行业集中度和产业集群效应，提出提升医疗器械行业集群度，激发产业创新集群活力的对策建议。     

银行股权集中度与经营绩效的相关性分析

银行股权集中度与治理结构有着密切联系,股权集中度影响银行经营绩效.运用委托代理理论,对我国上市银行股权集中度对激励机制、监督机制、约束机制绩效的影响进行分析,并通过实证检验,得出以下结论:(1)我国十家上市银行股权集中度均属于相对集中型和高度集中型,不存在分散集中型.(2)上市银行股权集中度与银行绩效具有显著相关性:股权集中度高,激励机制、监督机制都不能有效发挥作用,上市银行的绩效差;反之,股权集中度较低,股东有提高业绩的动力,银行绩效较好.(3)股权高度集中,不利于提高银行的绩效.     

股权结构、不确定性与现金持有异象 ——经验证据及其解读

以中国非金融业上市公司为研究对象,对现金持有量及其影响因素进行统计分析和实证检验,结果表明：在中国上市公司中,高额现金持有现象普遍存在;在职消费和代理成本都与现金持有量显著正相关;股权集中度和股权制衡度都与现金持有量之间存在显著的倒“U”型关系;经营活动不确定性和财务活动不确定性都与现金持有量显著负相关;盈利能力与现金持有量显著正相关;负债融资与现金持有量显著负相关。上述研究发现提供了一些现金持有异象的经验证据,说明中国上市公司的制度环境和治理结构具有一定的特殊性。     

Customer concentration and loan contract terms

We study pricing and non-pricing features of loan contracts to gauge how the credit market evaluates a firm’s customer-base profile and supply-chain relations. Higher customer concentration increases interest rate spreads and the number of restrictive covenants featured in newly initiated as well as renegotiated bank loans. Customer concentration also abbreviates the maturity of those loans as well as the relationship between firms and their banks. These effects are intensified by customers’ financial distress, the level of relationship-specific investments, and the use of trade credit in customer–supplier relations. Our evidence shows that a deeper exposure to a small set of large customers bears negative consequences for a firm’s relations with its creditors, revealing limits to integration along the supply chain.     

Shareholder Protection,Ownership, and Dividends: Russian Evidence

This article investigates the relation between corporate governance mechanisms and dividend policy in Russian firms. Using a sample of Russian listed firms over the period 1998–2003, we estimate models for dividend pay probability and payout size. We find that there has been a significant increase in dividend payout levels which coincide with improvements in legal shareholder protection. State controlled firms are more frequent dividend payers as compared to other majority owned firms. We also find that dual share firms, in which corporate charters protect minority interests, have a higher dividend pay probability; while firms reporting according to US GAAP, which may be less likely to manipulate earnings, have a lower dividend payout.     

区域经济集中与区域金融稳定的关系——以江苏省为例

采用江苏省13个地级市2002—2013年的相关数据,对区域经济集中与区域金融稳定的关系进行研究,结果表明：区域经济集中与区域金融稳定存在相关性;区域经济集中是区域金融稳定的格兰杰原因,区域经济集中的正向冲击会引起区域金融稳定先反向后正向的变化;随着区域经济集中度的上升,区域金融稳定呈现“先降后升”的U型变化。