企业规模、规模经济与产业集群

企业规模问题一直存在着截然相反的观点和主张,造成冲突的原因在于“企业规模”是一个各取所需的含混的概念。具有经济学意义的企业规模应该从两个相互正交的维度上———企业的横向规模和纵向规模———来度量。规模经济来自于横向规模的扩张,而纵向规模的扩张可能会带来规模不经济。产业集群是观察企业横向、纵向规模一个好的样本。区分企业规模的不同性质,将会使与规模经济相关的理论研究出现明晰的路径。     

强磁防垢技术研究及其在油田的现场应用

对国内某油田注水管线的结垢现象及水质和垢物成分进行了分析，探讨了强磁防垢机理，研究了磁处理的特点。通过室内晶相显微观察法。优化选择强磁处理的最佳磁参数，根据最佳磁参数设计出适合此油田现场使用的强磁防垢器，并在油田现场安装磁化器实施强磁防垢技术．观察磁防垢前后注水管线状况和结垢对比。现场实践表明，强磁防垢技术不但操作方便，而且可取得显著的效果和经济效益。     

The relationship between stock returns and volatility in international stock markets

This study examines the relationship between expected stock returns and volatility in the 12 largest international stock markets during January 1980 to December 2001. Consistent with most previous studies, we find a positive but insignificant relationship during the sample period for the majority of the markets based on parametric EGARCH-M models. However, using a flexible semiparametric specification of conditional variance, we find evidence of a significant negative relationship between expected returns and volatility in 6 out of the 12 markets. The results lend some support to the recent claim [Bekaert, G., Wu, G., 2000. Asymmetric volatility and risk in equity markets. Review of Financial Studies 13, 1–42; Whitelaw, R., 2000. Stock market risk and return: an empirical equilibrium approach. Review of Financial Studies 13, 521–547] that stock market returns are negatively correlated with stock market volatility.     

Employee stock ownership and financial performance in European countries: The moderating effects of uncertainty avoidance and social trust

This study investigates how the effect of employee stock ownership on financial performance may hinge on the diverse cultural and societal contexts of European countries. Based on agency and national culture theories, we hypothesize that the positive relationship between employee stock ownership and return on assets (ROA) is stronger in those nations with lower uncertainty avoidance and higher social trust. Using a multisource, time‐lagged, large‐scale dataset of 1,741 firms from 21 countries in Europe, our multilevel, random coefficient modeling analysis found evidence for these hypotheses, suggesting that uncertainty avoidance and social trust serve as important contextual cues in predicting the linkage between employee stock ownership and financial performance. Our supplemental analysis with distinction between the managerial and nonmanagerial employee stock ownership further indicates managerial employee stock ownership has a direct positive effect on ROA. Although nonmanagerial employee stock ownership had a nonsignificant association with ROA, the relationship was positive and significant when uncertainty avoidance was low and social trust was high. This research contributes to the existing literature by illuminating some of the contextual influences altering the effectiveness of employee stock ownership. Our findings also offer practical suggestions for effectively using employee stock ownership.     

Investing against the wind: contagion during the recent financial crisis

This article examines the effect of Warren Buffett’s investment in Goldman Sachs on 24 September 2008, during the subprime mortgage crisis. Although this event is arguably perceived to be the biggest expression of confidence in the financial market during the crisis, by conducting event studies, we do not find the major counterparties of Goldman Sachs displayed positive abnormal returns. Moreover, the abnormal return is not significantly related to the counterparty connection. We have similar findings on these financial institutions’ default probabilities using credit default swap.     

Analysing job creation effects of scaling up infrastructure spending in South Africa

In a first for South Africa, this article draws on literature on infrastructure productivity to model dynamic economy-wide employment impacts of infrastructure investment funded with different fiscal tools. Using a dynamic computable general equilibrium model, the South African investment plan is modelled, given the infrastructure externality. Alternative fiscal scenarios to finance the policy are modelled in the article. In the long run, unemployment decreases for all types of workers under one of the scenarios. In the short run, only elementary occupation workers benefit from a decrease in unemployment; for the rest, unemployment rises.     

收益率差异视角下股票流动性与资本结构关系的再检验

本文在股票收益率差异视角下，选择2000年1月到2015年12月期间中国沪、深市场307家上市公司数据，采用单方程估计法和联立方程组系统估计法研究我国上市公司股票流动性与资本结构的相互影响；并分别从股权分置改革、股权再融资、牛熊市行情三个方面对二者关系的变化与差异进行深入分析。结果表明：股票流动性与资本结构之间存在显著的负向关系，并且随着股票收益率水平的提高，负向影响越来越明显；股权分置改革后、满足再融资资格的上市公司以及牛市行情下两者的相互影响更显著。     

传统能源及碳交易价格与新能源股价——基于VAR和CAPM-GARCH模型的分析

文章构建VAR模型和CAPM-GARCH模型,分析检验了2010年7月初至2013年底期间传统能源和碳排放权交易价格对国内新能源上市公司股价波动的影响及新能源股票收益率的波动特点,研究发现:国内煤价对新能源公司股价有显著的正向影响,而国际油价的影响不显著;碳排放权交易价格也是引起新能源投资价值从而上市公司股价变动的重要因素;新能源公司股价指数对高科技股价指数并不敏感,反映出国内新能源上市公司科技含量不足,资本市场关注更多的是新能源的概念而非技术优势;国内新能源股票整体的系统风险在1.125~1.131之间,利好消息比利空消息能引起新能源股票收益率更大的波动。     

On the (non-)equivalence of IRR and NPV

The internal rate of return (IRR) is generally considered inferior to the net present value (NPV) as a tool for evaluating and ranking projects, despite its inherently useful comparability to the cost of capital and the return of other investment opportunities. We introduce the “selective IRR”, a return criterion which, as a selection of an extended set of possible IRRs, is NPV-consistent. The selective IRR always exists, is unique, easy to compute, and does not suffer from drawbacks that befall the project investment rate, the only other known NPV-consistent return criterion.     

供给侧改革背景下我国城市建设用地最优规模分析

本文基于边际等值原理，综合城市经济效益、社会效益、环境效益以及建设效益，构建多因子城市建设用地最优规模决策模型，并结合我国城市建设用地供给实际进行分析。结果显示：2001～2015年，我国城市发展经历了从建设用地短缺到最优及至过剩的过程，对建设用地增长的强依赖逐渐转变为弱依赖。城市建设用地增长与边际建设效益弱相关；与边际经济效益之间呈库兹涅茨倒U型曲线关系；与边际社会效益呈正相关、边际环境效益呈负相关。目前我国城市建设用地已经达到最优规模，其中建设用地供给与经济发展失调，是导致净效益下降的主要动因。