The impact on stock prices of deferral and elimination of internal control audit requirement for small firms

This paper examines the cumulative market reaction to the events related to deferral of internal control audit requirement under the Sarbanes-Oxley Act of 2002 and its elimination under the Dodd-Frank Act of 2010 for nonaccelerated filers (small firms). We document that small firms experienced negative cumulative abnormal returns around these events; and the differences between the cumulative abnormal returns for small firms and the two control groups (accelerated and large accelerated filers) were negative and significant at the 1% level. These results support the notion that market participants value the reliability of financial information irrespective of the firm size. Within the small firms, we find no firm characteristic significantly explains the market reaction to the events considered. That is, all small firms lost market value in reaction to the events that delayed and eliminated their internal control audit requirement.     

Effect of credible quality investment with Bertrand and Cournot competition

We show how credible revelation and ability to commit to quality choice effect equilibrium qualities and welfare when product market is either Bertrand or Cournot competition. We show that results depend on the type of competition but not generally on the cost of quality function. We show that with Bertrand competition, the equilibrium qualities are lower with credible commitment. Competition is moderated and producer surplus is higher and consumer surplus lower. With Cournot competition, higher quality will be better but lower quality will be worse with credible commitment. Consumer surplus is always greater with credible commitment and if cost does not increase too quickly with quality, producer surplus will also increase. Thus credible commitment is a collusive device with Bertrand competition but it can improve social welfare with Cournot competition. Received: February 8, 2000; revised version: February 14, 2002 RID="*" ID="*" The idea of this paper originated in the weekly workshops of Mordecai Kurz at Stanford. I am forever in debted to Mordecai and fellow students – Luis Cabral, Peter DeMarzo, John Hillas, Michihiro Kandori, Steve Langois, Patrick McAllister, Steve Sharpe, Peter Streufert, Steve Turnbull and Gyu-Ho Wang – for their criticism and encouragement. I also benefited from comments from Yi-Heng Chen, Jin-Li Hu, Kala Krishna, Jinji Naoto, Thomas J. Prusa, and Shyh-Fang Ueng at various later stages of this work. Last but not least, I am grateful for the detailed comments of the referee.     

A critical appraisal of the reporting quality of published randomized controlled trials in the fall injuries

To evaluate the quality of reporting in published randomized controlled trials (RTCs) in the field of fall injuries. The 188 RTCs published between 2001 and 2011, indexed in EMBASE and Medline databases were extracted through searching by appropriate keywords and EMTree classification terms. The evaluation trustworthiness was assured through parallel evaluations of two experts in epidemiology and biostatistics. About 40%–75% of papers had problems in reporting random allocation method, allocation concealment, random allocation implementation, blinding and similarity among groups, intention to treat and balancing benefits and harms. Moreover, at least 10% of papers inappropriately/not reported the design, protocol violations, sample size justification, subgroup/adjusted analyses, presenting flow diagram, drop outs, recruitment time, baseline data, suitable effect size on outcome, ancillary analyses, limitations and generalizability. Considering the shortcomings found and due to the importance of the RCTs for fall injury prevention programmes, their reporting quality should be improved.     

The Challenge of Humanistic Economics

The Center for Medicare and Medicaid Services (CMS) created the Hospital Compare Program in 2003 to increase transparency between healthcare providers and consumers. Implemented in 2005, this transparency consists of hospitals' collecting and making publicly available a set of hospital quality score measures. The CMS induced participation by financially penalizing hospitals that did not publicly report a specific subset of these measures (called “starter” measures). Three years into the program, the penalty for non-reporting both the starter measures and other (“non-starter”) measures was increased. I use a difference-in-differences methodology to analyze the effect of the increased CMS penalty on the likelihood that a hospital publicly reported its starter and non-starter measure scores. I find that the penalty had an economically and statistically insignificant effect on the probability that a hospital publicly reported its starter scores, but a statistically significant 8.0 percent effect (p-value<0.01) on whether it reported its non-starter scores. These findings are robust to a series of alternative empirical specifications.     

服务经济下北京城市空间结构的转型

城市空间结构是城市经济结构和城市社会结构的空间投影,城市经济结构的变化必然促进城市空间结构的转型。新中国成立后,几乎所有的中国城市都经历了由服务性城市向生产性城市的转型。改革开放以来,特别是1990年代的城市改革,使城市在区域中的中心功能地位得到强化,部分城市开始从生产性城市向服务性城市转型,服务经济快速增长,城市空间结构也经历了空间重组和功能转移。本研究运用北京市1949-2010年第三产业各部门增加值数据和主要时段第三产业用地空间布局状况,从产业链、产业支撑、产业融合和服务外包四种服务经济发展模式入手,分析了服务经济作为城市空间结构转型的内在机制和空间演化趋势。     

信息通信技术（ICT）创新扩散及影响因素空间计量分析

本文运用2001—2018年全国288个地级以上城市统计数据,对信息通信技术(ICT)创新扩散及影响因素进行研究。首先采取改进的Bass模型来测算ICT创新扩散速度,然后构建ICT创新扩散及其影响因素的面板数据固定效应动态SAR模型,并采用拟极大似然估计法对动态SAR模型进行参数估计。研究表明:ICT创新扩散的时空效应显著,创新扩散不仅受本地影响还受邻近城市的影响;人口密度、人口流量、户均ICT消费支出及ICT供给能力等因素对其创新扩散有显著影响,且这些因素短期空间溢出效应和长期回流反馈效应显著。     

主产区粮食生产时空格局及驱动因素

在国内国际双循环背景下厘清现阶段粮食生产的时空格局及驱动因素的空间分异规律,以更好地发挥粮食主产区对保障中国粮食安全的战略作用.基于粮食主产区2001—2017年粮食生产面板数据,利用探索性空间数据分析检验粮食主产区粮食生产格局的空间模式,采用地理加权回归模型分析粮食主产区粮食产量驱动因素的空间异质性.结果显示:主产区粮食产量处于高-高和低-低集聚的省份较多,处于高-低和低-高集聚的省份较少,且空间相关性随着时间波动下降;2001年及2017年种粮人数对粮食产量的驱动作用呈现出明显的空间异质性,其他因素对各地区粮食产量的驱动作用基本一致.基于上述研究结论,必须在充分考虑粮食主产区地域发展差异的基础上,从提升粮食单产、坚守耕地红线、规范化肥使用、推进农业科技化、防范农业灾害等方面着力改善,以期为中国粮食安全提供科学保障.     

基于完整性管理的油气管道施工质量评价

基于施工质量在管道完整性管理中的重要作用,提出了对油气管道施工质量进行科学合理评价的新方法。并对影响管道施工质量的焊接、防腐和埋设三个主要方面及其相关的质量影响因素进行了简要分析。根据实际情况与专家打分,应用多级模糊综合评价模型对某一埋地管道施工质量进行了综合评价。最后对提高施工质量提出了参考建议。     

科技企业孵化器运营绩效空间分布及影响因素

为深入研究各省份科技企业孵化器运营绩效空间分布特征及其影响因素,采用2013—2021年各省份样本数据进行实证分析。通过DEA-Malmquist指数模型测算科技企业孵化器运营绩效及其分解效率,探究其空间分布特征,同时采用空间杜宾模型分析影响各省份科技企业孵化器运营绩效的因素。结果表明：国内各省的孵化器运营绩效存在明显差异,导致孵化器运营绩效不佳的主要原因是技术进步减缓;国内科技企业孵化器运营绩效存在显著的空间相关性;经济发展水平、政府支持程度、数字社会建设水平、区域创新活力对科技企业孵化器运营绩效呈显著正向影响且在省份间呈现正向空间溢出现象。基于研究结论,建议通过建立健全孵化网络机制、制定差异化扶持政策、激发区域创新活力等方面进一步推进中国科技企业孵化器运营绩效的提升。     

珠江—西江经济带旅游业效率比较及时空演化——基于DEA-Malmquist模型分析

旅游业的提质增效是畅通国内经济循环的关键举措之一.基于DEA-Malmquist模型,测度2011—2018年珠江-西江经济带11市旅游效率,并进一步分析其时空差异特征.结果表明:珠江-西江经济带旅游综合效率值仍存在一定的提升空间,且西江流域旅游综合效率值整体高于珠江流域;珠江-西江经济带旅游业纯技术效率呈不稳定波动状态;珠江-西江经济带旅游业全要素生产率呈西高东低的态势,即西江流域在旅游资源开发和模式优化方面较珠江流域更具优势.因此,围绕旅游业帮扶体制建立、旅游业专业人才培养、以局部旅游资源优势带动区域旅游业协同发展等方面提出政策建议,为全面提升珠江-西江经济带旅游业效率和水平提供重要参考依据.